diff options
Diffstat (limited to 'drivers/clk')
| -rw-r--r-- | drivers/clk/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/clk/Makefile | 1 | ||||
| -rw-r--r-- | drivers/clk/bcm/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/clk/bcm/Makefile | 3 | ||||
| -rw-r--r-- | drivers/clk/bcm/clk-bcm281xx.c | 416 | ||||
| -rw-r--r-- | drivers/clk/bcm/clk-kona-setup.c | 769 | ||||
| -rw-r--r-- | drivers/clk/bcm/clk-kona.c | 1033 | ||||
| -rw-r--r-- | drivers/clk/bcm/clk-kona.h | 410 |
8 files changed, 2642 insertions, 0 deletions
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 7641965d208..f9f605695e4 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -111,4 +111,5 @@ source "drivers/clk/qcom/Kconfig" endmenu +source "drivers/clk/bcm/Kconfig" source "drivers/clk/mvebu/Kconfig" diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index a367a983171..88af4a399d6 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_ARCH_VT8500) += clk-vt8500.o obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o obj-$(CONFIG_COMMON_CLK_XGENE) += clk-xgene.o obj-$(CONFIG_COMMON_CLK_AT91) += at91/ +obj-$(CONFIG_ARCH_BCM_MOBILE) += bcm/ obj-$(CONFIG_ARCH_HI3xxx) += hisilicon/ obj-$(CONFIG_COMMON_CLK_KEYSTONE) += keystone/ ifeq ($(CONFIG_COMMON_CLK), y) diff --git a/drivers/clk/bcm/Kconfig b/drivers/clk/bcm/Kconfig new file mode 100644 index 00000000000..a7262fb8ce5 --- /dev/null +++ b/drivers/clk/bcm/Kconfig @@ -0,0 +1,9 @@ +config CLK_BCM_KONA + bool "Broadcom Kona CCU clock support" + depends on ARCH_BCM_MOBILE + depends on COMMON_CLK + default y + help + Enable common clock framework support for Broadcom SoCs + using "Kona" style clock control units, including those + in the BCM281xx family. diff --git a/drivers/clk/bcm/Makefile b/drivers/clk/bcm/Makefile new file mode 100644 index 00000000000..cf93359aa86 --- /dev/null +++ b/drivers/clk/bcm/Makefile @@ -0,0 +1,3 @@ +obj-$(CONFIG_CLK_BCM_KONA) += clk-kona.o +obj-$(CONFIG_CLK_BCM_KONA) += clk-kona-setup.o +obj-$(CONFIG_CLK_BCM_KONA) += clk-bcm281xx.o diff --git a/drivers/clk/bcm/clk-bcm281xx.c b/drivers/clk/bcm/clk-bcm281xx.c new file mode 100644 index 00000000000..3c66de696ae --- /dev/null +++ b/drivers/clk/bcm/clk-bcm281xx.c @@ -0,0 +1,416 @@ +/* + * Copyright (C) 2013 Broadcom Corporation + * Copyright 2013 Linaro Limited + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include "clk-kona.h" +#include "dt-bindings/clock/bcm281xx.h" + +/* bcm11351 CCU device tree "compatible" strings */ +#define BCM11351_DT_ROOT_CCU_COMPAT "brcm,bcm11351-root-ccu" +#define BCM11351_DT_AON_CCU_COMPAT "brcm,bcm11351-aon-ccu" +#define BCM11351_DT_HUB_CCU_COMPAT "brcm,bcm11351-hub-ccu" +#define BCM11351_DT_MASTER_CCU_COMPAT "brcm,bcm11351-master-ccu" +#define BCM11351_DT_SLAVE_CCU_COMPAT "brcm,bcm11351-slave-ccu" + +/* Root CCU clocks */ + +static struct peri_clk_data frac_1m_data = { + .gate = HW_SW_GATE(0x214, 16, 0, 1), + .trig = TRIGGER(0x0e04, 0), + .div = FRAC_DIVIDER(0x0e00, 0, 22, 16), + .clocks = CLOCKS("ref_crystal"), +}; + +/* AON CCU clocks */ + +static struct peri_clk_data hub_timer_data = { + .gate = HW_SW_GATE(0x0414, 16, 0, 1), + .clocks = CLOCKS("bbl_32k", + "frac_1m", + "dft_19_5m"), + .sel = SELECTOR(0x0a10, 0, 2), + .trig = TRIGGER(0x0a40, 4), +}; + +static struct peri_clk_data pmu_bsc_data = { + .gate = HW_SW_GATE(0x0418, 16, 0, 1), + .clocks = CLOCKS("ref_crystal", + "pmu_bsc_var", + "bbl_32k"), + .sel = SELECTOR(0x0a04, 0, 2), + .div = DIVIDER(0x0a04, 3, 4), + .trig = TRIGGER(0x0a40, 0), +}; + +static struct peri_clk_data pmu_bsc_var_data = { + .clocks = CLOCKS("var_312m", + "ref_312m"), + .sel = SELECTOR(0x0a00, 0, 2), + .div = DIVIDER(0x0a00, 4, 5), + .trig = TRIGGER(0x0a40, 2), +}; + +/* Hub CCU clocks */ + +static struct peri_clk_data tmon_1m_data = { + .gate = HW_SW_GATE(0x04a4, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "frac_1m"), + .sel = SELECTOR(0x0e74, 0, 2), + .trig = TRIGGER(0x0e84, 1), +}; + +/* Master CCU clocks */ + +static struct peri_clk_data sdio1_data = { + .gate = HW_SW_GATE(0x0358, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_52m", + "ref_52m", + "var_96m", + "ref_96m"), + .sel = SELECTOR(0x0a28, 0, 3), + .div = DIVIDER(0x0a28, 4, 14), + .trig = TRIGGER(0x0afc, 9), +}; + +static struct peri_clk_data sdio2_data = { + .gate = HW_SW_GATE(0x035c, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_52m", + "ref_52m", + "var_96m", + "ref_96m"), + .sel = SELECTOR(0x0a2c, 0, 3), + .div = DIVIDER(0x0a2c, 4, 14), + .trig = TRIGGER(0x0afc, 10), +}; + +static struct peri_clk_data sdio3_data = { + .gate = HW_SW_GATE(0x0364, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_52m", + "ref_52m", + "var_96m", + "ref_96m"), + .sel = SELECTOR(0x0a34, 0, 3), + .div = DIVIDER(0x0a34, 4, 14), + .trig = TRIGGER(0x0afc, 12), +}; + +static struct peri_clk_data sdio4_data = { + .gate = HW_SW_GATE(0x0360, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_52m", + "ref_52m", + "var_96m", + "ref_96m"), + .sel = SELECTOR(0x0a30, 0, 3), + .div = DIVIDER(0x0a30, 4, 14), + .trig = TRIGGER(0x0afc, 11), +}; + +static struct peri_clk_data usb_ic_data = { + .gate = HW_SW_GATE(0x0354, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_96m", + "ref_96m"), + .div = FIXED_DIVIDER(2), + .sel = SELECTOR(0x0a24, 0, 2), + .trig = TRIGGER(0x0afc, 7), +}; + +/* also called usbh_48m */ +static struct peri_clk_data hsic2_48m_data = { + .gate = HW_SW_GATE(0x0370, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_96m", + "ref_96m"), + .sel = SELECTOR(0x0a38, 0, 2), + .div = FIXED_DIVIDER(2), + .trig = TRIGGER(0x0afc, 5), +}; + +/* also called usbh_12m */ +static struct peri_clk_data hsic2_12m_data = { + .gate = HW_SW_GATE(0x0370, 20, 4, 5), + .div = DIVIDER(0x0a38, 12, 2), + .clocks = CLOCKS("ref_crystal", + "var_96m", + "ref_96m"), + .pre_div = FIXED_DIVIDER(2), + .sel = SELECTOR(0x0a38, 0, 2), + .trig = TRIGGER(0x0afc, 5), +}; + +/* Slave CCU clocks */ + +static struct peri_clk_data uartb_data = { + .gate = HW_SW_GATE(0x0400, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_156m", + "ref_156m"), + .sel = SELECTOR(0x0a10, 0, 2), + .div = FRAC_DIVIDER(0x0a10, 4, 12, 8), + .trig = TRIGGER(0x0afc, 2), +}; + +static struct peri_clk_data uartb2_data = { + .gate = HW_SW_GATE(0x0404, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_156m", + "ref_156m"), + .sel = SELECTOR(0x0a14, 0, 2), + .div = FRAC_DIVIDER(0x0a14, 4, 12, 8), + .trig = TRIGGER(0x0afc, 3), +}; + +static struct peri_clk_data uartb3_data = { + .gate = HW_SW_GATE(0x0408, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_156m", + "ref_156m"), + .sel = SELECTOR(0x0a18, 0, 2), + .div = FRAC_DIVIDER(0x0a18, 4, 12, 8), + .trig = TRIGGER(0x0afc, 4), +}; + +static struct peri_clk_data uartb4_data = { + .gate = HW_SW_GATE(0x0408, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_156m", + "ref_156m"), + .sel = SELECTOR(0x0a1c, 0, 2), + .div = FRAC_DIVIDER(0x0a1c, 4, 12, 8), + .trig = TRIGGER(0x0afc, 5), +}; + +static struct peri_clk_data ssp0_data = { + .gate = HW_SW_GATE(0x0410, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_104m", + "ref_104m", + "var_96m", + "ref_96m"), + .sel = SELECTOR(0x0a20, 0, 3), + .div = DIVIDER(0x0a20, 4, 14), + .trig = TRIGGER(0x0afc, 6), +}; + +static struct peri_clk_data ssp2_data = { + .gate = HW_SW_GATE(0x0418, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_104m", + "ref_104m", + "var_96m", + "ref_96m"), + .sel = SELECTOR(0x0a28, 0, 3), + .div = DIVIDER(0x0a28, 4, 14), + .trig = TRIGGER(0x0afc, 8), +}; + +static struct peri_clk_data bsc1_data = { + .gate = HW_SW_GATE(0x0458, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_104m", + "ref_104m", + "var_13m", + "ref_13m"), + .sel = SELECTOR(0x0a64, 0, 3), + .trig = TRIGGER(0x0afc, 23), +}; + +static struct peri_clk_data bsc2_data = { + .gate = HW_SW_GATE(0x045c, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_104m", + "ref_104m", + "var_13m", + "ref_13m"), + .sel = SELECTOR(0x0a68, 0, 3), + .trig = TRIGGER(0x0afc, 24), +}; + +static struct peri_clk_data bsc3_data = { + .gate = HW_SW_GATE(0x0484, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_104m", + "ref_104m", + "var_13m", + "ref_13m"), + .sel = SELECTOR(0x0a84, 0, 3), + .trig = TRIGGER(0x0b00, 2), +}; + +static struct peri_clk_data pwm_data = { + .gate = HW_SW_GATE(0x0468, 18, 2, 3), + .clocks = CLOCKS("ref_crystal", + "var_104m"), + .sel = SELECTOR(0x0a70, 0, 2), + .div = DIVIDER(0x0a70, 4, 3), + .trig = TRIGGER(0x0afc, 15), +}; + +/* + * CCU setup routines + * + * These are called from kona_dt_ccu_setup() to initialize the array + * of clocks provided by the CCU. Once allocated, the entries in + * the array are initialized by calling kona_clk_setup() with the + * initialization data for each clock. They return 0 if successful + * or an error code otherwise. + */ +static int __init bcm281xx_root_ccu_clks_setup(struct ccu_data *ccu) +{ + struct clk **clks; + size_t count = BCM281XX_ROOT_CCU_CLOCK_COUNT; + + clks = kzalloc(count * sizeof(*clks), GFP_KERNEL); + if (!clks) { + pr_err("%s: failed to allocate root clocks\n", __func__); + return -ENOMEM; + } + ccu->data.clks = clks; + ccu->data.clk_num = count; + + PERI_CLK_SETUP(clks, ccu, BCM281XX_ROOT_CCU_FRAC_1M, frac_1m); + + return 0; +} + +static int __init bcm281xx_aon_ccu_clks_setup(struct ccu_data *ccu) +{ + struct clk **clks; + size_t count = BCM281XX_AON_CCU_CLOCK_COUNT; + + clks = kzalloc(count * sizeof(*clks), GFP_KERNEL); + if (!clks) { + pr_err("%s: failed to allocate aon clocks\n", __func__); + return -ENOMEM; + } + ccu->data.clks = clks; + ccu->data.clk_num = count; + + PERI_CLK_SETUP(clks, ccu, BCM281XX_AON_CCU_HUB_TIMER, hub_timer); + PERI_CLK_SETUP(clks, ccu, BCM281XX_AON_CCU_PMU_BSC, pmu_bsc); + PERI_CLK_SETUP(clks, ccu, BCM281XX_AON_CCU_PMU_BSC_VAR, pmu_bsc_var); + + return 0; +} + +static int __init bcm281xx_hub_ccu_clks_setup(struct ccu_data *ccu) +{ + struct clk **clks; + size_t count = BCM281XX_HUB_CCU_CLOCK_COUNT; + + clks = kzalloc(count * sizeof(*clks), GFP_KERNEL); + if (!clks) { + pr_err("%s: failed to allocate hub clocks\n", __func__); + return -ENOMEM; + } + ccu->data.clks = clks; + ccu->data.clk_num = count; + + PERI_CLK_SETUP(clks, ccu, BCM281XX_HUB_CCU_TMON_1M, tmon_1m); + + return 0; +} + +static int __init bcm281xx_master_ccu_clks_setup(struct ccu_data *ccu) +{ + struct clk **clks; + size_t count = BCM281XX_MASTER_CCU_CLOCK_COUNT; + + clks = kzalloc(count * sizeof(*clks), GFP_KERNEL); + if (!clks) { + pr_err("%s: failed to allocate master clocks\n", __func__); + return -ENOMEM; + } + ccu->data.clks = clks; + ccu->data.clk_num = count; + + PERI_CLK_SETUP(clks, ccu, BCM281XX_MASTER_CCU_SDIO1, sdio1); + PERI_CLK_SETUP(clks, ccu, BCM281XX_MASTER_CCU_SDIO2, sdio2); + PERI_CLK_SETUP(clks, ccu, BCM281XX_MASTER_CCU_SDIO3, sdio3); + PERI_CLK_SETUP(clks, ccu, BCM281XX_MASTER_CCU_SDIO4, sdio4); + PERI_CLK_SETUP(clks, ccu, BCM281XX_MASTER_CCU_USB_IC, usb_ic); + PERI_CLK_SETUP(clks, ccu, BCM281XX_MASTER_CCU_HSIC2_48M, hsic2_48m); + PERI_CLK_SETUP(clks, ccu, BCM281XX_MASTER_CCU_HSIC2_12M, hsic2_12m); + + return 0; +} + +static int __init bcm281xx_slave_ccu_clks_setup(struct ccu_data *ccu) +{ + struct clk **clks; + size_t count = BCM281XX_SLAVE_CCU_CLOCK_COUNT; + + clks = kzalloc(count * sizeof(*clks), GFP_KERNEL); + if (!clks) { + pr_err("%s: failed to allocate slave clocks\n", __func__); + return -ENOMEM; + } + ccu->data.clks = clks; + ccu->data.clk_num = count; + + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_UARTB, uartb); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_UARTB2, uartb2); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_UARTB3, uartb3); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_UARTB4, uartb4); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_SSP0, ssp0); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_SSP2, ssp2); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_BSC1, bsc1); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_BSC2, bsc2); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_BSC3, bsc3); + PERI_CLK_SETUP(clks, ccu, BCM281XX_SLAVE_CCU_PWM, pwm); + + return 0; +} + +/* Device tree match table callback functions */ + +static void __init kona_dt_root_ccu_setup(struct device_node *node) +{ + kona_dt_ccu_setup(node, bcm281xx_root_ccu_clks_setup); +} + +static void __init kona_dt_aon_ccu_setup(struct device_node *node) +{ + kona_dt_ccu_setup(node, bcm281xx_aon_ccu_clks_setup); +} + +static void __init kona_dt_hub_ccu_setup(struct device_node *node) +{ + kona_dt_ccu_setup(node, bcm281xx_hub_ccu_clks_setup); +} + +static void __init kona_dt_master_ccu_setup(struct device_node *node) +{ + kona_dt_ccu_setup(node, bcm281xx_master_ccu_clks_setup); +} + +static void __init kona_dt_slave_ccu_setup(struct device_node *node) +{ + kona_dt_ccu_setup(node, bcm281xx_slave_ccu_clks_setup); +} + +CLK_OF_DECLARE(bcm11351_root_ccu, BCM11351_DT_ROOT_CCU_COMPAT, + kona_dt_root_ccu_setup); +CLK_OF_DECLARE(bcm11351_aon_ccu, BCM11351_DT_AON_CCU_COMPAT, + kona_dt_aon_ccu_setup); +CLK_OF_DECLARE(bcm11351_hub_ccu, BCM11351_DT_HUB_CCU_COMPAT, + kona_dt_hub_ccu_setup); +CLK_OF_DECLARE(bcm11351_master_ccu, BCM11351_DT_MASTER_CCU_COMPAT, + kona_dt_master_ccu_setup); +CLK_OF_DECLARE(bcm11351_slave_ccu, BCM11351_DT_SLAVE_CCU_COMPAT, + kona_dt_slave_ccu_setup); diff --git a/drivers/clk/bcm/clk-kona-setup.c b/drivers/clk/bcm/clk-kona-setup.c new file mode 100644 index 00000000000..f1e88fe6bb4 --- /dev/null +++ b/drivers/clk/bcm/clk-kona-setup.c @@ -0,0 +1,769 @@ +/* + * Copyright (C) 2013 Broadcom Corporation + * Copyright 2013 Linaro Limited + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/io.h> +#include <linux/of_address.h> + +#include "clk-kona.h" + +/* These are used when a selector or trigger is found to be unneeded */ +#define selector_clear_exists(sel) ((sel)->width = 0) +#define trigger_clear_exists(trig) FLAG_CLEAR(trig, TRIG, EXISTS) + +LIST_HEAD(ccu_list); /* The list of set up CCUs */ + +/* Validity checking */ + +static bool clk_requires_trigger(struct kona_clk *bcm_clk) +{ + struct peri_clk_data *peri = bcm_clk->peri; + struct bcm_clk_sel *sel; + struct bcm_clk_div *div; + + if (bcm_clk->type != bcm_clk_peri) + return false; + + sel = &peri->sel; + if (sel->parent_count && selector_exists(sel)) + return true; + + div = &peri->div; + if (!divider_exists(div)) + return false; + + /* Fixed dividers don't need triggers */ + if (!divider_is_fixed(div)) + return true; + + div = &peri->pre_div; + + return divider_exists(div) && !divider_is_fixed(div); +} + +static bool peri_clk_data_offsets_valid(struct kona_clk *bcm_clk) +{ + struct peri_clk_data *peri; + struct bcm_clk_gate *gate; + struct bcm_clk_div *div; + struct bcm_clk_sel *sel; + struct bcm_clk_trig *trig; + const char *name; + u32 range; + u32 limit; + + BUG_ON(bcm_clk->type != bcm_clk_peri); + peri = bcm_clk->peri; + name = bcm_clk->name; + range = bcm_clk->ccu->range; + + limit = range - sizeof(u32); + limit = round_down(limit, sizeof(u32)); + + gate = &peri->gate; + if (gate_exists(gate)) { + if (gate->offset > limit) { + pr_err("%s: bad gate offset for %s (%u > %u)\n", + __func__, name, gate->offset, limit); + return false; + } + } + + div = &peri->div; + if (divider_exists(div)) { + if (div->offset > limit) { + pr_err("%s: bad divider offset for %s (%u > %u)\n", + __func__, name, div->offset, limit); + return false; + } + } + + div = &peri->pre_div; + if (divider_exists(div)) { + if (div->offset > limit) { + pr_err("%s: bad pre-divider offset for %s " + "(%u > %u)\n", + __func__, name, div->offset, limit); + return false; + } + } + + sel = &peri->sel; + if (selector_exists(sel)) { + if (sel->offset > limit) { + pr_err("%s: bad selector offset for %s (%u > %u)\n", + __func__, name, sel->offset, limit); + return false; + } + } + + trig = &peri->trig; + if (trigger_exists(trig)) { + if (trig->offset > limit) { + pr_err("%s: bad trigger offset for %s (%u > %u)\n", + __func__, name, trig->offset, limit); + return false; + } + } + + trig = &peri->pre_trig; + if (trigger_exists(trig)) { + if (trig->offset > limit) { + pr_err("%s: bad pre-trigger offset for %s (%u > %u)\n", + __func__, name, trig->offset, limit); + return false; + } + } + + return true; +} + +/* A bit position must be less than the number of bits in a 32-bit register. */ +static bool bit_posn_valid(u32 bit_posn, const char *field_name, + const char *clock_name) +{ + u32 limit = BITS_PER_BYTE * sizeof(u32) - 1; + + if (bit_posn > limit) { + pr_err("%s: bad %s bit for %s (%u > %u)\n", __func__, + field_name, clock_name, bit_posn, limit); + return false; + } + return true; +} + +/* + * A bitfield must be at least 1 bit wide. Both the low-order and + * high-order bits must lie within a 32-bit register. We require + * fields to be less than 32 bits wide, mainly because we use + * shifting to produce field masks, and shifting a full word width + * is not well-defined by the C standard. + */ +static bool bitfield_valid(u32 shift, u32 width, const char *field_name, + const char *clock_name) +{ + u32 limit = BITS_PER_BYTE * sizeof(u32); + + if (!width) { + pr_err("%s: bad %s field width 0 for %s\n", __func__, + field_name, clock_name); + return false; + } + if (shift + width > limit) { + pr_err("%s: bad %s for %s (%u + %u > %u)\n", __func__, + field_name, clock_name, shift, width, limit); + return false; + } + return true; +} + +/* + * All gates, if defined, have a status bit, and for hardware-only + * gates, that's it. Gates that can be software controlled also + * have an enable bit. And a gate that can be hardware or software + * controlled will have a hardware/software select bit. + */ +static bool gate_valid(struct bcm_clk_gate *gate, const char *field_name, + const char *clock_name) +{ + if (!bit_posn_valid(gate->status_bit, "gate status", clock_name)) + return false; + + if (gate_is_sw_controllable(gate)) { + if (!bit_posn_valid(gate->en_bit, "gate enable", clock_name)) + return false; + + if (gate_is_hw_controllable(gate)) { + if (!bit_posn_valid(gate->hw_sw_sel_bit, + "gate hw/sw select", + clock_name)) + return false; + } + } else { + BUG_ON(!gate_is_hw_controllable(gate)); + } + + return true; +} + +/* + * A selector bitfield must be valid. Its parent_sel array must + * also be reasonable for the field. + */ +static bool sel_valid(struct bcm_clk_sel *sel, const char *field_name, + const char *clock_name) +{ + if (!bitfield_valid(sel->shift, sel->width, field_name, clock_name)) + return false; + + if (sel->parent_count) { + u32 max_sel; + u32 limit; + + /* + * Make sure the selector field can hold all the + * selector values we expect to be able to use. A + * clock only needs to have a selector defined if it + * has more than one parent. And in that case the + * highest selector value will be in the last entry + * in the array. + */ + max_sel = sel->parent_sel[sel->parent_count - 1]; + limit = (1 << sel->width) - 1; + if (max_sel > limit) { + pr_err("%s: bad selector for %s " + "(%u needs > %u bits)\n", + __func__, clock_name, max_sel, + sel->width); + return false; + } + } else { + pr_warn("%s: ignoring selector for %s (no parents)\n", + __func__, clock_name); + selector_clear_exists(sel); + kfree(sel->parent_sel); + sel->parent_sel = NULL; + } + + return true; +} + +/* + * A fixed divider just needs to be non-zero. A variable divider + * has to have a valid divider bitfield, and if it has a fraction, + * the width of the fraction must not be no more than the width of + * the divider as a whole. + */ +static bool div_valid(struct bcm_clk_div *div, const char *field_name, + const char *clock_name) +{ + if (divider_is_fixed(div)) { + /* Any fixed divider value but 0 is OK */ + if (div->fixed == 0) { + pr_err("%s: bad %s fixed value 0 for %s\n", __func__, + field_name, clock_name); + return false; + } + return true; + } + if (!bitfield_valid(div->shift, div->width, field_name, clock_name)) + return false; + + if (divider_has_fraction(div)) + if (div->frac_width > div->width) { + pr_warn("%s: bad %s fraction width for %s (%u > %u)\n", + __func__, field_name, clock_name, + div->frac_width, div->width); + return false; + } + + return true; +} + +/* + * If a clock has two dividers, the combined number of fractional + * bits must be representable in a 32-bit unsigned value. This + * is because we scale up a dividend using both dividers before + * dividing to improve accuracy, and we need to avoid overflow. + */ +static bool kona_dividers_valid(struct kona_clk *bcm_clk) +{ + struct peri_clk_data *peri = bcm_clk->peri; + struct bcm_clk_div *div; + struct bcm_clk_div *pre_div; + u32 limit; + + BUG_ON(bcm_clk->type != bcm_clk_peri); + + if (!divider_exists(&peri->div) || !divider_exists(&peri->pre_div)) + return true; + + div = &peri->div; + pre_div = &peri->pre_div; + if (divider_is_fixed(div) || divider_is_fixed(pre_div)) + return true; + + limit = BITS_PER_BYTE * sizeof(u32); + + return div->frac_width + pre_div->frac_width <= limit; +} + + +/* A trigger just needs to represent a valid bit position */ +static bool trig_valid(struct bcm_clk_trig *trig, const char *field_name, + const char *clock_name) +{ + return bit_posn_valid(trig->bit, field_name, clock_name); +} + +/* Determine whether the set of peripheral clock registers are valid. */ +static bool +peri_clk_data_valid(struct kona_clk *bcm_clk) +{ + struct peri_clk_data *peri; + struct bcm_clk_gate *gate; + struct bcm_clk_sel *sel; + struct bcm_clk_div *div; + struct bcm_clk_div *pre_div; + struct bcm_clk_trig *trig; + const char *name; + + BUG_ON(bcm_clk->type != bcm_clk_peri); + + /* + * First validate register offsets. This is the only place + * where we need something from the ccu, so we do these + * together. + */ + if (!peri_clk_data_offsets_valid(bcm_clk)) + return false; + + peri = bcm_clk->peri; + name = bcm_clk->name; + gate = &peri->gate; + if (gate_exists(gate) && !gate_valid(gate, "gate", name)) + return false; + + sel = &peri->sel; + if (selector_exists(sel)) { + if (!sel_valid(sel, "selector", name)) + return false; + + } else if (sel->parent_count > 1) { + pr_err("%s: multiple parents but no selector for %s\n", + __func__, name); + + return false; + } + + div = &peri->div; + pre_div = &peri->pre_div; + if (divider_exists(div)) { + if (!div_valid(div, "divider", name)) + return false; + + if (divider_exists(pre_div)) + if (!div_valid(pre_div, "pre-divider", name)) + return false; + } else if (divider_exists(pre_div)) { + pr_err("%s: pre-divider but no divider for %s\n", __func__, + name); + return false; + } + + trig = &peri->trig; + if (trigger_exists(trig)) { + if (!trig_valid(trig, "trigger", name)) + return false; + + if (trigger_exists(&peri->pre_trig)) { + if (!trig_valid(trig, "pre-trigger", name)) { + return false; + } + } + if (!clk_requires_trigger(bcm_clk)) { + pr_warn("%s: ignoring trigger for %s (not needed)\n", + __func__, name); + trigger_clear_exists(trig); + } + } else if (trigger_exists(&peri->pre_trig)) { + pr_err("%s: pre-trigger but no trigger for %s\n", __func__, + name); + return false; + } else if (clk_requires_trigger(bcm_clk)) { + pr_err("%s: required trigger missing for %s\n", __func__, + name); + return false; + } + + return kona_dividers_valid(bcm_clk); +} + +static bool kona_clk_valid(struct kona_clk *bcm_clk) +{ + switch (bcm_clk->type) { + case bcm_clk_peri: + if (!peri_clk_data_valid(bcm_clk)) + return false; + break; + default: + pr_err("%s: unrecognized clock type (%d)\n", __func__, + (int)bcm_clk->type); + return false; + } + return true; +} + +/* + * Scan an array of parent clock names to determine whether there + * are any entries containing BAD_CLK_NAME. Such entries are + * placeholders for non-supported clocks. Keep track of the + * position of each clock name in the original array. + * + * Allocates an array of pointers to to hold the names of all + * non-null entries in the original array, and returns a pointer to + * that array in *names. This will be used for registering the + * clock with the common clock code. On successful return, + * *count indicates how many entries are in that names array. + * + * If there is more than one entry in the resulting names array, + * another array is allocated to record the parent selector value + * for each (defined) parent clock. This is the value that + * represents this parent clock in the clock's source selector + * register. The position of the clock in the original parent array + * defines that selector value. The number of entries in this array + * is the same as the number of entries in the parent names array. + * + * The array of selector values is returned. If the clock has no + * parents, no selector is required and a null pointer is returned. + * + * Returns a null pointer if the clock names array supplied was + * null. (This is not an error.) + * + * Returns a pointer-coded error if an error occurs. + */ +static u32 *parent_process(const char *clocks[], + u32 *count, const char ***names) +{ + static const char **parent_names; + static u32 *parent_sel; + const char **clock; + u32 parent_count; + u32 bad_count = 0; + u32 orig_count; + u32 i; + u32 j; + + *count = 0; /* In case of early return */ + *names = NULL; + if (!clocks) + return NULL; + + /* + * Count the number of names in the null-terminated array, + * and find out how many of those are actually clock names. + */ + for (clock = clocks; *clock; clock++) + if (*clock == BAD_CLK_NAME) + bad_count++; + orig_count = (u32)(clock - clocks); + parent_count = orig_count - bad_count; + + /* If all clocks are unsupported, we treat it as no clock */ + if (!parent_count) + return NULL; + + /* Avoid exceeding our parent clock limit */ + if (parent_count > PARENT_COUNT_MAX) { + pr_err("%s: too many parents (%u > %u)\n", __func__, + parent_count, PARENT_COUNT_MAX); + return ERR_PTR(-EINVAL); + } + + /* + * There is one parent name for each defined parent clock. + * We also maintain an array containing the selector value + * for each defined clock. If there's only one clock, the + * selector is not required, but we allocate space for the + * array anyway to keep things simple. + */ + parent_names = kmalloc(parent_count * sizeof(parent_names), GFP_KERNEL); + if (!parent_names) { + pr_err("%s: error allocating %u parent names\n", __func__, + parent_count); + return ERR_PTR(-ENOMEM); + } + + /* There is at least one parent, so allocate a selector array */ + + parent_sel = kmalloc(parent_count * sizeof(*parent_sel), GFP_KERNEL); + if (!parent_sel) { + pr_err("%s: error allocating %u parent selectors\n", __func__, + parent_count); + kfree(parent_names); + + return ERR_PTR(-ENOMEM); + } + + /* Now fill in the parent names and selector arrays */ + for (i = 0, j = 0; i < orig_count; i++) { + if (clocks[i] != BAD_CLK_NAME) { + parent_names[j] = clocks[i]; + parent_sel[j] = i; + j++; + } + } + *names = parent_names; + *count = parent_count; + + return parent_sel; +} + +static int +clk_sel_setup(const char **clocks, struct bcm_clk_sel *sel, + struct clk_init_data *init_data) +{ + const char **parent_names = NULL; + u32 parent_count = 0; + u32 *parent_sel; + + /* + * If a peripheral clock has multiple parents, the value + * used by the hardware to select that parent is represented + * by the parent clock's position in the "clocks" list. Some + * values don't have defined or supported clocks; these will + * have BAD_CLK_NAME entries in the parents[] array. The + * list is terminated by a NULL entry. + * + * We need to supply (only) the names of defined parent + * clocks when registering a clock though, so we use an + * array of parent selector values to map between the + * indexes the common clock code uses and the selector + * values we need. + */ + parent_sel = parent_process(clocks, &parent_count, &parent_names); + if (IS_ERR(parent_sel)) { + int ret = PTR_ERR(parent_sel); + + pr_err("%s: error processing parent clocks for %s (%d)\n", + __func__, init_data->name, ret); + + return ret; + } + + init_data->parent_names = parent_names; + init_data->num_parents = parent_count; + + sel->parent_count = parent_count; + sel->parent_sel = parent_sel; + + return 0; +} + +static void clk_sel_teardown(struct bcm_clk_sel *sel, + struct clk_init_data *init_data) +{ + kfree(sel->parent_sel); + sel->parent_sel = NULL; + sel->parent_count = 0; + + init_data->num_parents = 0; + kfree(init_data->parent_names); + init_data->parent_names = NULL; +} + +static void peri_clk_teardown(struct peri_clk_data *data, + struct clk_init_data *init_data) +{ + clk_sel_teardown(&data->sel, init_data); + init_data->ops = NULL; +} + +/* + * Caller is responsible for freeing the parent_names[] and + * parent_sel[] arrays in the peripheral clock's "data" structure + * that can be assigned if the clock has one or more parent clocks + * associated with it. + */ +static int peri_clk_setup(struct ccu_data *ccu, struct peri_clk_data *data, + struct clk_init_data *init_data) +{ + init_data->ops = &kona_peri_clk_ops; + init_data->flags = 0; + + return clk_sel_setup(data->clocks, &data->sel, init_data); +} + +static void bcm_clk_teardown(struct kona_clk *bcm_clk) +{ + switch (bcm_clk->type) { + case bcm_clk_peri: + peri_clk_teardown(bcm_clk->data, &bcm_clk->init_data); + break; + default: + break; + } + bcm_clk->data = NULL; + bcm_clk->type = bcm_clk_none; +} + +static void kona_clk_teardown(struct clk *clk) +{ + struct clk_hw *hw; + struct kona_clk *bcm_clk; + + if (!clk) + return; + + hw = __clk_get_hw(clk); + if (!hw) { + pr_err("%s: clk %p has null hw pointer\n", __func__, clk); + return; + } + clk_unregister(clk); + + bcm_clk = to_kona_clk(hw); + bcm_clk_teardown(bcm_clk); +} + +struct clk *kona_clk_setup(struct ccu_data *ccu, const char *name, + enum bcm_clk_type type, void *data) +{ + struct kona_clk *bcm_clk; + struct clk_init_data *init_data; + struct clk *clk = NULL; + + bcm_clk = kzalloc(sizeof(*bcm_clk), GFP_KERNEL); + if (!bcm_clk) { + pr_err("%s: failed to allocate bcm_clk for %s\n", __func__, + name); + return NULL; + } + bcm_clk->ccu = ccu; + bcm_clk->name = name; + + init_data = &bcm_clk->init_data; + init_data->name = name; + switch (type) { + case bcm_clk_peri: + if (peri_clk_setup(ccu, data, init_data)) + goto out_free; + break; + default: + data = NULL; + break; + } + bcm_clk->type = type; + bcm_clk->data = data; + + /* Make sure everything makes sense before we set it up */ + if (!kona_clk_valid(bcm_clk)) { + pr_err("%s: clock data invalid for %s\n", __func__, name); + goto out_teardown; + } + + bcm_clk->hw.init = init_data; + clk = clk_register(NULL, &bcm_clk->hw); + if (IS_ERR(clk)) { + pr_err("%s: error registering clock %s (%ld)\n", __func__, + name, PTR_ERR(clk)); + goto out_teardown; + } + BUG_ON(!clk); + + return clk; +out_teardown: + bcm_clk_teardown(bcm_clk); +out_free: + kfree(bcm_clk); + + return NULL; +} + +static void ccu_clks_teardown(struct ccu_data *ccu) +{ + u32 i; + + for (i = 0; i < ccu->data.clk_num; i++) + kona_clk_teardown(ccu->data.clks[i]); + kfree(ccu->data.clks); +} + +static void kona_ccu_teardown(struct ccu_data *ccu) +{ + if (!ccu) + return; + + if (!ccu->base) + goto done; + + of_clk_del_provider(ccu->node); /* safe if never added */ + ccu_clks_teardown(ccu); + list_del(&ccu->links); + of_node_put(ccu->node); + iounmap(ccu->base); +done: + kfree(ccu->name); + kfree(ccu); +} + +/* + * Set up a CCU. Call the provided ccu_clks_setup callback to + * initialize the array of clocks provided by the CCU. + */ +void __init kona_dt_ccu_setup(struct device_node *node, + int (*ccu_clks_setup)(struct ccu_data *)) +{ + struct ccu_data *ccu; + struct resource res = { 0 }; + resource_size_t range; + int ret; + + ccu = kzalloc(sizeof(*ccu), GFP_KERNEL); + if (ccu) + ccu->name = kstrdup(node->name, GFP_KERNEL); + if (!ccu || !ccu->name) { + pr_err("%s: unable to allocate CCU struct for %s\n", + __func__, node->name); + kfree(ccu); + + return; + } + + ret = of_address_to_resource(node, 0, &res); + if (ret) { + pr_err("%s: no valid CCU registers found for %s\n", __func__, + node->name); + goto out_err; + } + + range = resource_size(&res); + if (range > (resource_size_t)U32_MAX) { + pr_err("%s: address range too large for %s\n", __func__, + node->name); + goto out_err; + } + + ccu->range = (u32)range; + ccu->base = ioremap(res.start, ccu->range); + if (!ccu->base) { + pr_err("%s: unable to map CCU registers for %s\n", __func__, + node->name); + goto out_err; + } + + spin_lock_init(&ccu->lock); + INIT_LIST_HEAD(&ccu->links); + ccu->node = of_node_get(node); + + list_add_tail(&ccu->links, &ccu_list); + + /* Set up clocks array (in ccu->data) */ + if (ccu_clks_setup(ccu)) + goto out_err; + + ret = of_clk_add_provider(node, of_clk_src_onecell_get, &ccu->data); + if (ret) { + pr_err("%s: error adding ccu %s as provider (%d)\n", __func__, + node->name, ret); + goto out_err; + } + + if (!kona_ccu_init(ccu)) + pr_err("Broadcom %s initialization had errors\n", node->name); + + return; +out_err: + kona_ccu_teardown(ccu); + pr_err("Broadcom %s setup aborted\n", node->name); +} diff --git a/drivers/clk/bcm/clk-kona.c b/drivers/clk/bcm/clk-kona.c new file mode 100644 index 00000000000..e3d339e0830 --- /dev/null +++ b/drivers/clk/bcm/clk-kona.c @@ -0,0 +1,1033 @@ +/* + * Copyright (C) 2013 Broadcom Corporation + * Copyright 2013 Linaro Limited + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include "clk-kona.h" + +#include <linux/delay.h> + +#define CCU_ACCESS_PASSWORD 0xA5A500 +#define CLK_GATE_DELAY_LOOP 2000 + +/* Bitfield operations */ + +/* Produces a mask of set bits covering a range of a 32-bit value */ +static inline u32 bitfield_mask(u32 shift, u32 width) +{ + return ((1 << width) - 1) << shift; +} + +/* Extract the value of a bitfield found within a given register value */ +static inline u32 bitfield_extract(u32 reg_val, u32 shift, u32 width) +{ + return (reg_val & bitfield_mask(shift, width)) >> shift; +} + +/* Replace the value of a bitfield found within a given register value */ +static inline u32 bitfield_replace(u32 reg_val, u32 shift, u32 width, u32 val) +{ + u32 mask = bitfield_mask(shift, width); + + return (reg_val & ~mask) | (val << shift); +} + +/* Divider and scaling helpers */ + +/* + * Implement DIV_ROUND_CLOSEST() for 64-bit dividend and both values + * unsigned. Note that unlike do_div(), the remainder is discarded + * and the return value is the quotient (not the remainder). + */ +u64 do_div_round_closest(u64 dividend, unsigned long divisor) +{ + u64 result; + + result = dividend + ((u64)divisor >> 1); + (void)do_div(result, divisor); + + return result; +} + +/* Convert a divider into the scaled divisor value it represents. */ +static inline u64 scaled_div_value(struct bcm_clk_div *div, u32 reg_div) +{ + return (u64)reg_div + ((u64)1 << div->frac_width); +} + +/* + * Build a scaled divider value as close as possible to the + * given whole part (div_value) and fractional part (expressed + * in billionths). + */ +u64 scaled_div_build(struct bcm_clk_div *div, u32 div_value, u32 billionths) +{ + u64 combined; + + BUG_ON(!div_value); + BUG_ON(billionths >= BILLION); + + combined = (u64)div_value * BILLION + billionths; + combined <<= div->frac_width; + + return do_div_round_closest(combined, BILLION); +} + +/* The scaled minimum divisor representable by a divider */ +static inline u64 +scaled_div_min(struct bcm_clk_div *div) +{ + if (divider_is_fixed(div)) + return (u64)div->fixed; + + return scaled_div_value(div, 0); +} + +/* The scaled maximum divisor representable by a divider */ +u64 scaled_div_max(struct bcm_clk_div *div) +{ + u32 reg_div; + + if (divider_is_fixed(div)) + return (u64)div->fixed; + + reg_div = ((u32)1 << div->width) - 1; + + return scaled_div_value(div, reg_div); +} + +/* + * Convert a scaled divisor into its divider representation as + * stored in a divider register field. + */ +static inline u32 +divider(struct bcm_clk_div *div, u64 scaled_div) +{ + BUG_ON(scaled_div < scaled_div_min(div)); + BUG_ON(scaled_div > scaled_div_max(div)); + + return (u32)(scaled_div - ((u64)1 << div->frac_width)); +} + +/* Return a rate scaled for use when dividing by a scaled divisor. */ +static inline u64 +scale_rate(struct bcm_clk_div *div, u32 rate) +{ + if (divider_is_fixed(div)) + return (u64)rate; + + return (u64)rate << div->frac_width; +} + +/* CCU access */ + +/* Read a 32-bit register value from a CCU's address space. */ +static inline u32 __ccu_read(struct ccu_data *ccu, u32 reg_offset) +{ + return readl(ccu->base + reg_offset); +} + +/* Write a 32-bit register value into a CCU's address space. */ +static inline void +__ccu_write(struct ccu_data *ccu, u32 reg_offset, u32 reg_val) +{ + writel(reg_val, ccu->base + reg_offset); +} + +static inline unsigned long ccu_lock(struct ccu_data *ccu) +{ + unsigned long flags; + + spin_lock_irqsave(&ccu->lock, flags); + + return flags; +} +static inline void ccu_unlock(struct ccu_data *ccu, unsigned long flags) +{ + spin_unlock_irqrestore(&ccu->lock, flags); +} + +/* + * Enable/disable write access to CCU protected registers. The + * WR_ACCESS register for all CCUs is at offset 0. + */ +static inline void __ccu_write_enable(struct ccu_data *ccu) +{ + if (ccu->write_enabled) { + pr_err("%s: access already enabled for %s\n", __func__, + ccu->name); + return; + } + ccu->write_enabled = true; + __ccu_write(ccu, 0, CCU_ACCESS_PASSWORD | 1); +} + +static inline void __ccu_write_disable(struct ccu_data *ccu) +{ + if (!ccu->write_enabled) { + pr_err("%s: access wasn't enabled for %s\n", __func__, + ccu->name); + return; + } + + __ccu_write(ccu, 0, CCU_ACCESS_PASSWORD); + ccu->write_enabled = false; +} + +/* + * Poll a register in a CCU's address space, returning when the + * specified bit in that register's value is set (or clear). Delay + * a microsecond after each read of the register. Returns true if + * successful, or false if we gave up trying. + * + * Caller must ensure the CCU lock is held. + */ +static inline bool +__ccu_wait_bit(struct ccu_data *ccu, u32 reg_offset, u32 bit, bool want) +{ + unsigned int tries; + u32 bit_mask = 1 << bit; + + for (tries = 0; tries < CLK_GATE_DELAY_LOOP; tries++) { + u32 val; + bool bit_val; + + val = __ccu_read(ccu, reg_offset); + bit_val = (val & bit_mask) != 0; + if (bit_val == want) + return true; + udelay(1); + } + return false; +} + +/* Gate operations */ + +/* Determine whether a clock is gated. CCU lock must be held. */ +static bool +__is_clk_gate_enabled(struct ccu_data *ccu, struct bcm_clk_gate *gate) +{ + u32 bit_mask; + u32 reg_val; + + /* If there is no gate we can assume it's enabled. */ + if (!gate_exists(gate)) + return true; + + bit_mask = 1 << gate->status_bit; + reg_val = __ccu_read(ccu, gate->offset); + + return (reg_val & bit_mask) != 0; +} + +/* Determine whether a clock is gated. */ +static bool +is_clk_gate_enabled(struct ccu_data *ccu, struct bcm_clk_gate *gate) +{ + long flags; + bool ret; + + /* Avoid taking the lock if we can */ + if (!gate_exists(gate)) + return true; + + flags = ccu_lock(ccu); + ret = __is_clk_gate_enabled(ccu, gate); + ccu_unlock(ccu, flags); + + return ret; +} + +/* + * Commit our desired gate state to the hardware. + * Returns true if successful, false otherwise. + */ +static bool +__gate_commit(struct ccu_data *ccu, struct bcm_clk_gate *gate) +{ + u32 reg_val; + u32 mask; + bool enabled = false; + + BUG_ON(!gate_exists(gate)); + if (!gate_is_sw_controllable(gate)) + return true; /* Nothing we can change */ + + reg_val = __ccu_read(ccu, gate->offset); + + /* For a hardware/software gate, set which is in control */ + if (gate_is_hw_controllable(gate)) { + mask = (u32)1 << gate->hw_sw_sel_bit; + if (gate_is_sw_managed(gate)) + reg_val |= mask; + else + reg_val &= ~mask; + } + + /* + * If software is in control, enable or disable the gate. + * If hardware is, clear the enabled bit for good measure. + * If a software controlled gate can't be disabled, we're + * required to write a 0 into the enable bit (but the gate + * will be enabled). + */ + mask = (u32)1 << gate->en_bit; + if (gate_is_sw_managed(gate) && (enabled = gate_is_enabled(gate)) && + !gate_is_no_disable(gate)) + reg_val |= mask; + else + reg_val &= ~mask; + + __ccu_write(ccu, gate->offset, reg_val); + + /* For a hardware controlled gate, we're done */ + if (!gate_is_sw_managed(gate)) + return true; + + /* Otherwise wait for the gate to be in desired state */ + return __ccu_wait_bit(ccu, gate->offset, gate->status_bit, enabled); +} + +/* + * Initialize a gate. Our desired state (hardware/software select, + * and if software, its enable state) is committed to hardware + * without the usual checks to see if it's already set up that way. + * Returns true if successful, false otherwise. + */ +static bool gate_init(struct ccu_data *ccu, struct bcm_clk_gate *gate) +{ + if (!gate_exists(gate)) + return true; + return __gate_commit(ccu, gate); +} + +/* + * Set a gate to enabled or disabled state. Does nothing if the + * gate is not currently under software control, or if it is already + * in the requested state. Returns true if successful, false + * otherwise. CCU lock must be held. + */ +static bool +__clk_gate(struct ccu_data *ccu, struct bcm_clk_gate *gate, bool enable) +{ + bool ret; + + if (!gate_exists(gate) || !gate_is_sw_managed(gate)) + return true; /* Nothing to do */ + + if (!enable && gate_is_no_disable(gate)) { + pr_warn("%s: invalid gate disable request (ignoring)\n", + __func__); + return true; + } + + if (enable == gate_is_enabled(gate)) + return true; /* No change */ + + gate_flip_enabled(gate); + ret = __gate_commit(ccu, gate); + if (!ret) + gate_flip_enabled(gate); /* Revert the change */ + + return ret; +} + +/* Enable or disable a gate. Returns 0 if successful, -EIO otherwise */ +static int clk_gate(struct ccu_data *ccu, const char *name, + struct bcm_clk_gate *gate, bool enable) +{ + unsigned long flags; + bool success; + + /* + * Avoid taking the lock if we can. We quietly ignore + * requests to change state that don't make sense. + */ + if (!gate_exists(gate) || !gate_is_sw_managed(gate)) + return 0; + if (!enable && gate_is_no_disable(gate)) + return 0; + + flags = ccu_lock(ccu); + __ccu_write_enable(ccu); + + success = __clk_gate(ccu, gate, enable); + + __ccu_write_disable(ccu); + ccu_unlock(ccu, flags); + + if (success) + return 0; + + pr_err("%s: failed to %s gate for %s\n", __func__, + enable ? "enable" : "disable", name); + + return -EIO; +} + +/* Trigger operations */ + +/* + * Caller must ensure CCU lock is held and access is enabled. + * Returns true if successful, false otherwise. + */ +static bool __clk_trigger(struct ccu_data *ccu, struct bcm_clk_trig *trig) +{ + /* Trigger the clock and wait for it to finish */ + __ccu_write(ccu, trig->offset, 1 << trig->bit); + + return __ccu_wait_bit(ccu, trig->offset, trig->bit, false); +} + +/* Divider operations */ + +/* Read a divider value and return the scaled divisor it represents. */ +static u64 divider_read_scaled(struct ccu_data *ccu, struct bcm_clk_div *div) +{ + unsigned long flags; + u32 reg_val; + u32 reg_div; + + if (divider_is_fixed(div)) + return (u64)div->fixed; + + flags = ccu_lock(ccu); + reg_val = __ccu_read(ccu, div->offset); + ccu_unlock(ccu, flags); + + /* Extract the full divider field from the register value */ + reg_div = bitfield_extract(reg_val, div->shift, div->width); + + /* Return the scaled divisor value it represents */ + return scaled_div_value(div, reg_div); +} + +/* + * Convert a divider's scaled divisor value into its recorded form + * and commit it into the hardware divider register. + * + * Returns 0 on success. Returns -EINVAL for invalid arguments. + * Returns -ENXIO if gating failed, and -EIO if a trigger failed. + */ +static int __div_commit(struct ccu_data *ccu, struct bcm_clk_gate *gate, + struct bcm_clk_div *div, struct bcm_clk_trig *trig) +{ + bool enabled; + u32 reg_div; + u32 reg_val; + int ret = 0; + + BUG_ON(divider_is_fixed(div)); + + /* + * If we're just initializing the divider, and no initial + * state was defined in the device tree, we just find out + * what its current value is rather than updating it. + */ + if (div->scaled_div == BAD_SCALED_DIV_VALUE) { + reg_val = __ccu_read(ccu, div->offset); + reg_div = bitfield_extract(reg_val, div->shift, div->width); + div->scaled_div = scaled_div_value(div, reg_div); + + return 0; + } + + /* Convert the scaled divisor to the value we need to record */ + reg_div = divider(div, div->scaled_div); + + /* Clock needs to be enabled before changing the rate */ + enabled = __is_clk_gate_enabled(ccu, gate); + if (!enabled && !__clk_gate(ccu, gate, true)) { + ret = -ENXIO; + goto out; + } + + /* Replace the divider value and record the result */ + reg_val = __ccu_read(ccu, div->offset); + reg_val = bitfield_replace(reg_val, div->shift, div->width, reg_div); + __ccu_write(ccu, div->offset, reg_val); + + /* If the trigger fails we still want to disable the gate */ + if (!__clk_trigger(ccu, trig)) + ret = -EIO; + + /* Disable the clock again if it was disabled to begin with */ + if (!enabled && !__clk_gate(ccu, gate, false)) + ret = ret ? ret : -ENXIO; /* return first error */ +out: + return ret; +} + +/* + * Initialize a divider by committing our desired state to hardware + * without the usual checks to see if it's already set up that way. + * Returns true if successful, false otherwise. + */ +static bool div_init(struct ccu_data *ccu, struct bcm_clk_gate *gate, + struct bcm_clk_div *div, struct bcm_clk_trig *trig) +{ + if (!divider_exists(div) || divider_is_fixed(div)) + return true; + return !__div_commit(ccu, gate, div, trig); +} + +static int divider_write(struct ccu_data *ccu, struct bcm_clk_gate *gate, + struct bcm_clk_div *div, struct bcm_clk_trig *trig, + u64 scaled_div) +{ + unsigned long flags; + u64 previous; + int ret; + + BUG_ON(divider_is_fixed(div)); + + previous = div->scaled_div; + if (previous == scaled_div) + return 0; /* No change */ + + div->scaled_div = scaled_div; + + flags = ccu_lock(ccu); + __ccu_write_enable(ccu); + + ret = __div_commit(ccu, gate, div, trig); + + __ccu_write_disable(ccu); + ccu_unlock(ccu, flags); + + if (ret) + div->scaled_div = previous; /* Revert the change */ + + return ret; + +} + +/* Common clock rate helpers */ + +/* + * Implement the common clock framework recalc_rate method, taking + * into account a divider and an optional pre-divider. The + * pre-divider register pointer may be NULL. + */ +static unsigned long clk_recalc_rate(struct ccu_data *ccu, + struct bcm_clk_div *div, struct bcm_clk_div *pre_div, + unsigned long parent_rate) +{ + u64 scaled_parent_rate; + u64 scaled_div; + u64 result; + + if (!divider_exists(div)) + return parent_rate; + + if (parent_rate > (unsigned long)LONG_MAX) + return 0; /* actually this would be a caller bug */ + + /* + * If there is a pre-divider, divide the scaled parent rate + * by the pre-divider value first. In this case--to improve + * accuracy--scale the parent rate by *both* the pre-divider + * value and the divider before actually computing the + * result of the pre-divider. + * + * If there's only one divider, just scale the parent rate. + */ + if (pre_div && divider_exists(pre_div)) { + u64 scaled_rate; + + scaled_rate = scale_rate(pre_div, parent_rate); + scaled_rate = scale_rate(div, scaled_rate); + scaled_div = divider_read_scaled(ccu, pre_div); + scaled_parent_rate = do_div_round_closest(scaled_rate, + scaled_div); + } else { + scaled_parent_rate = scale_rate(div, parent_rate); + } + + /* + * Get the scaled divisor value, and divide the scaled + * parent rate by that to determine this clock's resulting + * rate. + */ + scaled_div = divider_read_scaled(ccu, div); + result = do_div_round_closest(scaled_parent_rate, scaled_div); + + return (unsigned long)result; +} + +/* + * Compute the output rate produced when a given parent rate is fed + * into two dividers. The pre-divider can be NULL, and even if it's + * non-null it may be nonexistent. It's also OK for the divider to + * be nonexistent, and in that case the pre-divider is also ignored. + * + * If scaled_div is non-null, it is used to return the scaled divisor + * value used by the (downstream) divider to produce that rate. + */ +static long round_rate(struct ccu_data *ccu, struct bcm_clk_div *div, + struct bcm_clk_div *pre_div, + unsigned long rate, unsigned long parent_rate, + u64 *scaled_div) +{ + u64 scaled_parent_rate; + u64 min_scaled_div; + u64 max_scaled_div; + u64 best_scaled_div; + u64 result; + + BUG_ON(!divider_exists(div)); + BUG_ON(!rate); + BUG_ON(parent_rate > (u64)LONG_MAX); + + /* + * If there is a pre-divider, divide the scaled parent rate + * by the pre-divider value first. In this case--to improve + * accuracy--scale the parent rate by *both* the pre-divider + * value and the divider before actually computing the + * result of the pre-divider. + * + * If there's only one divider, just scale the parent rate. + * + * For simplicity we treat the pre-divider as fixed (for now). + */ + if (divider_exists(pre_div)) { + u64 scaled_rate; + u64 scaled_pre_div; + + scaled_rate = scale_rate(pre_div, parent_rate); + scaled_rate = scale_rate(div, scaled_rate); + scaled_pre_div = divider_read_scaled(ccu, pre_div); + scaled_parent_rate = do_div_round_closest(scaled_rate, + scaled_pre_div); + } else { + scaled_parent_rate = scale_rate(div, parent_rate); + } + + /* + * Compute the best possible divider and ensure it is in + * range. A fixed divider can't be changed, so just report + * the best we can do. + */ + if (!divider_is_fixed(div)) { + best_scaled_div = do_div_round_closest(scaled_parent_rate, + rate); + min_scaled_div = scaled_div_min(div); + max_scaled_div = scaled_div_max(div); + if (best_scaled_div > max_scaled_div) + best_scaled_div = max_scaled_div; + else if (best_scaled_div < min_scaled_div) + best_scaled_div = min_scaled_div; + } else { + best_scaled_div = divider_read_scaled(ccu, div); + } + + /* OK, figure out the resulting rate */ + result = do_div_round_closest(scaled_parent_rate, best_scaled_div); + + if (scaled_div) + *scaled_div = best_scaled_div; + + return (long)result; +} + +/* Common clock parent helpers */ + +/* + * For a given parent selector (register field) value, find the + * index into a selector's parent_sel array that contains it. + * Returns the index, or BAD_CLK_INDEX if it's not found. + */ +static u8 parent_index(struct bcm_clk_sel *sel, u8 parent_sel) +{ + u8 i; + + BUG_ON(sel->parent_count > (u32)U8_MAX); + for (i = 0; i < sel->parent_count; i++) + if (sel->parent_sel[i] == parent_sel) + return i; + return BAD_CLK_INDEX; +} + +/* + * Fetch the current value of the selector, and translate that into + * its corresponding index in the parent array we registered with + * the clock framework. + * + * Returns parent array index that corresponds with the value found, + * or BAD_CLK_INDEX if the found value is out of range. + */ +static u8 selector_read_index(struct ccu_data *ccu, struct bcm_clk_sel *sel) +{ + unsigned long flags; + u32 reg_val; + u32 parent_sel; + u8 index; + + /* If there's no selector, there's only one parent */ + if (!selector_exists(sel)) + return 0; + + /* Get the value in the selector register */ + flags = ccu_lock(ccu); + reg_val = __ccu_read(ccu, sel->offset); + ccu_unlock(ccu, flags); + + parent_sel = bitfield_extract(reg_val, sel->shift, sel->width); + + /* Look up that selector's parent array index and return it */ + index = parent_index(sel, parent_sel); + if (index == BAD_CLK_INDEX) + pr_err("%s: out-of-range parent selector %u (%s 0x%04x)\n", + __func__, parent_sel, ccu->name, sel->offset); + + return index; +} + +/* + * Commit our desired selector value to the hardware. + * + * Returns 0 on success. Returns -EINVAL for invalid arguments. + * Returns -ENXIO if gating failed, and -EIO if a trigger failed. + */ +static int +__sel_commit(struct ccu_data *ccu, struct bcm_clk_gate *gate, + struct bcm_clk_sel *sel, struct bcm_clk_trig *trig) +{ + u32 parent_sel; + u32 reg_val; + bool enabled; + int ret = 0; + + BUG_ON(!selector_exists(sel)); + + /* + * If we're just initializing the selector, and no initial + * state was defined in the device tree, we just find out + * what its current value is rather than updating it. + */ + if (sel->clk_index == BAD_CLK_INDEX) { + u8 index; + + reg_val = __ccu_read(ccu, sel->offset); + parent_sel = bitfield_extract(reg_val, sel->shift, sel->width); + index = parent_index(sel, parent_sel); + if (index == BAD_CLK_INDEX) + return -EINVAL; + sel->clk_index = index; + + return 0; + } + + BUG_ON((u32)sel->clk_index >= sel->parent_count); + parent_sel = sel->parent_sel[sel->clk_index]; + + /* Clock needs to be enabled before changing the parent */ + enabled = __is_clk_gate_enabled(ccu, gate); + if (!enabled && !__clk_gate(ccu, gate, true)) + return -ENXIO; + + /* Replace the selector value and record the result */ + reg_val = __ccu_read(ccu, sel->offset); + reg_val = bitfield_replace(reg_val, sel->shift, sel->width, parent_sel); + __ccu_write(ccu, sel->offset, reg_val); + + /* If the trigger fails we still want to disable the gate */ + if (!__clk_trigger(ccu, trig)) + ret = -EIO; + + /* Disable the clock again if it was disabled to begin with */ + if (!enabled && !__clk_gate(ccu, gate, false)) + ret = ret ? ret : -ENXIO; /* return first error */ + + return ret; +} + +/* + * Initialize a selector by committing our desired state to hardware + * without the usual checks to see if it's already set up that way. + * Returns true if successful, false otherwise. + */ +static bool sel_init(struct ccu_data *ccu, struct bcm_clk_gate *gate, + struct bcm_clk_sel *sel, struct bcm_clk_trig *trig) +{ + if (!selector_exists(sel)) + return true; + return !__sel_commit(ccu, gate, sel, trig); +} + +/* + * Write a new value into a selector register to switch to a + * different parent clock. Returns 0 on success, or an error code + * (from __sel_commit()) otherwise. + */ +static int selector_write(struct ccu_data *ccu, struct bcm_clk_gate *gate, + struct bcm_clk_sel *sel, struct bcm_clk_trig *trig, + u8 index) +{ + unsigned long flags; + u8 previous; + int ret; + + previous = sel->clk_index; + if (previous == index) + return 0; /* No change */ + + sel->clk_index = index; + + flags = ccu_lock(ccu); + __ccu_write_enable(ccu); + + ret = __sel_commit(ccu, gate, sel, trig); + + __ccu_write_disable(ccu); + ccu_unlock(ccu, flags); + + if (ret) + sel->clk_index = previous; /* Revert the change */ + + return ret; +} + +/* Clock operations */ + +static int kona_peri_clk_enable(struct clk_hw *hw) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct bcm_clk_gate *gate = &bcm_clk->peri->gate; + + return clk_gate(bcm_clk->ccu, bcm_clk->name, gate, true); +} + +static void kona_peri_clk_disable(struct clk_hw *hw) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct bcm_clk_gate *gate = &bcm_clk->peri->gate; + + (void)clk_gate(bcm_clk->ccu, bcm_clk->name, gate, false); +} + +static int kona_peri_clk_is_enabled(struct clk_hw *hw) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct bcm_clk_gate *gate = &bcm_clk->peri->gate; + + return is_clk_gate_enabled(bcm_clk->ccu, gate) ? 1 : 0; +} + +static unsigned long kona_peri_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct peri_clk_data *data = bcm_clk->peri; + + return clk_recalc_rate(bcm_clk->ccu, &data->div, &data->pre_div, + parent_rate); +} + +static long kona_peri_clk_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct bcm_clk_div *div = &bcm_clk->peri->div; + + if (!divider_exists(div)) + return __clk_get_rate(hw->clk); + + /* Quietly avoid a zero rate */ + return round_rate(bcm_clk->ccu, div, &bcm_clk->peri->pre_div, + rate ? rate : 1, *parent_rate, NULL); +} + +static int kona_peri_clk_set_parent(struct clk_hw *hw, u8 index) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct peri_clk_data *data = bcm_clk->peri; + struct bcm_clk_sel *sel = &data->sel; + struct bcm_clk_trig *trig; + int ret; + + BUG_ON(index >= sel->parent_count); + + /* If there's only one parent we don't require a selector */ + if (!selector_exists(sel)) + return 0; + + /* + * The regular trigger is used by default, but if there's a + * pre-trigger we want to use that instead. + */ + trig = trigger_exists(&data->pre_trig) ? &data->pre_trig + : &data->trig; + + ret = selector_write(bcm_clk->ccu, &data->gate, sel, trig, index); + if (ret == -ENXIO) { + pr_err("%s: gating failure for %s\n", __func__, bcm_clk->name); + ret = -EIO; /* Don't proliferate weird errors */ + } else if (ret == -EIO) { + pr_err("%s: %strigger failed for %s\n", __func__, + trig == &data->pre_trig ? "pre-" : "", + bcm_clk->name); + } + + return ret; +} + +static u8 kona_peri_clk_get_parent(struct clk_hw *hw) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct peri_clk_data *data = bcm_clk->peri; + u8 index; + + index = selector_read_index(bcm_clk->ccu, &data->sel); + + /* Not all callers would handle an out-of-range value gracefully */ + return index == BAD_CLK_INDEX ? 0 : index; +} + +static int kona_peri_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct kona_clk *bcm_clk = to_kona_clk(hw); + struct peri_clk_data *data = bcm_clk->peri; + struct bcm_clk_div *div = &data->div; + u64 scaled_div = 0; + int ret; + + if (parent_rate > (unsigned long)LONG_MAX) + return -EINVAL; + + if (rate == __clk_get_rate(hw->clk)) + return 0; + + if (!divider_exists(div)) + return rate == parent_rate ? 0 : -EINVAL; + + /* + * A fixed divider can't be changed. (Nor can a fixed + * pre-divider be, but for now we never actually try to + * change that.) Tolerate a request for a no-op change. + */ + if (divider_is_fixed(&data->div)) + return rate == parent_rate ? 0 : -EINVAL; + + /* + * Get the scaled divisor value needed to achieve a clock + * rate as close as possible to what was requested, given + * the parent clock rate supplied. + */ + (void)round_rate(bcm_clk->ccu, div, &data->pre_div, + rate ? rate : 1, parent_rate, &scaled_div); + + /* + * We aren't updating any pre-divider at this point, so + * we'll use the regular trigger. + */ + ret = divider_write(bcm_clk->ccu, &data->gate, &data->div, + &data->trig, scaled_div); + if (ret == -ENXIO) { + pr_err("%s: gating failure for %s\n", __func__, bcm_clk->name); + ret = -EIO; /* Don't proliferate weird errors */ + } else if (ret == -EIO) { + pr_err("%s: trigger failed for %s\n", __func__, bcm_clk->name); + } + + return ret; +} + +struct clk_ops kona_peri_clk_ops = { + .enable = kona_peri_clk_enable, + .disable = kona_peri_clk_disable, + .is_enabled = kona_peri_clk_is_enabled, + .recalc_rate = kona_peri_clk_recalc_rate, + .round_rate = kona_peri_clk_round_rate, + .set_parent = kona_peri_clk_set_parent, + .get_parent = kona_peri_clk_get_parent, + .set_rate = kona_peri_clk_set_rate, +}; + +/* Put a peripheral clock into its initial state */ +static bool __peri_clk_init(struct kona_clk *bcm_clk) +{ + struct ccu_data *ccu = bcm_clk->ccu; + struct peri_clk_data *peri = bcm_clk->peri; + const char *name = bcm_clk->name; + struct bcm_clk_trig *trig; + + BUG_ON(bcm_clk->type != bcm_clk_peri); + + if (!gate_init(ccu, &peri->gate)) { + pr_err("%s: error initializing gate for %s\n", __func__, name); + return false; + } + if (!div_init(ccu, &peri->gate, &peri->div, &peri->trig)) { + pr_err("%s: error initializing divider for %s\n", __func__, + name); + return false; + } + + /* + * For the pre-divider and selector, the pre-trigger is used + * if it's present, otherwise we just use the regular trigger. + */ + trig = trigger_exists(&peri->pre_trig) ? &peri->pre_trig + : &peri->trig; + + if (!div_init(ccu, &peri->gate, &peri->pre_div, trig)) { + pr_err("%s: error initializing pre-divider for %s\n", __func__, + name); + return false; + } + + if (!sel_init(ccu, &peri->gate, &peri->sel, trig)) { + pr_err("%s: error initializing selector for %s\n", __func__, + name); + return false; + } + + return true; +} + +static bool __kona_clk_init(struct kona_clk *bcm_clk) +{ + switch (bcm_clk->type) { + case bcm_clk_peri: + return __peri_clk_init(bcm_clk); + default: + BUG(); + } + return -EINVAL; +} + +/* Set a CCU and all its clocks into their desired initial state */ +bool __init kona_ccu_init(struct ccu_data *ccu) +{ + unsigned long flags; + unsigned int which; + struct clk **clks = ccu->data.clks; + bool success = true; + + flags = ccu_lock(ccu); + __ccu_write_enable(ccu); + + for (which = 0; which < ccu->data.clk_num; which++) { + struct kona_clk *bcm_clk; + + if (!clks[which]) + continue; + bcm_clk = to_kona_clk(__clk_get_hw(clks[which])); + success &= __kona_clk_init(bcm_clk); + } + + __ccu_write_disable(ccu); + ccu_unlock(ccu, flags); + return success; +} diff --git a/drivers/clk/bcm/clk-kona.h b/drivers/clk/bcm/clk-kona.h new file mode 100644 index 00000000000..5e139adc3dc --- /dev/null +++ b/drivers/clk/bcm/clk-kona.h @@ -0,0 +1,410 @@ +/* + * Copyright (C) 2013 Broadcom Corporation + * Copyright 2013 Linaro Limited + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _CLK_KONA_H +#define _CLK_KONA_H + +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/of.h> +#include <linux/clk-provider.h> + +#define BILLION 1000000000 + +/* The common clock framework uses u8 to represent a parent index */ +#define PARENT_COUNT_MAX ((u32)U8_MAX) + +#define BAD_CLK_INDEX U8_MAX /* Can't ever be valid */ +#define BAD_CLK_NAME ((const char *)-1) + +#define BAD_SCALED_DIV_VALUE U64_MAX + +/* + * Utility macros for object flag management. If possible, flags + * should be defined such that 0 is the desired default value. + */ +#define FLAG(type, flag) BCM_CLK_ ## type ## _FLAGS_ ## flag +#define FLAG_SET(obj, type, flag) ((obj)->flags |= FLAG(type, flag)) +#define FLAG_CLEAR(obj, type, flag) ((obj)->flags &= ~(FLAG(type, flag))) +#define FLAG_FLIP(obj, type, flag) ((obj)->flags ^= FLAG(type, flag)) +#define FLAG_TEST(obj, type, flag) (!!((obj)->flags & FLAG(type, flag))) + +/* Clock field state tests */ + +#define gate_exists(gate) FLAG_TEST(gate, GATE, EXISTS) +#define gate_is_enabled(gate) FLAG_TEST(gate, GATE, ENABLED) +#define gate_is_hw_controllable(gate) FLAG_TEST(gate, GATE, HW) +#define gate_is_sw_controllable(gate) FLAG_TEST(gate, GATE, SW) +#define gate_is_sw_managed(gate) FLAG_TEST(gate, GATE, SW_MANAGED) +#define gate_is_no_disable(gate) FLAG_TEST(gate, GATE, NO_DISABLE) + +#define gate_flip_enabled(gate) FLAG_FLIP(gate, GATE, ENABLED) + +#define divider_exists(div) FLAG_TEST(div, DIV, EXISTS) +#define divider_is_fixed(div) FLAG_TEST(div, DIV, FIXED) +#define divider_has_fraction(div) (!divider_is_fixed(div) && \ + (div)->frac_width > 0) + +#define selector_exists(sel) ((sel)->width != 0) +#define trigger_exists(trig) FLAG_TEST(trig, TRIG, EXISTS) + +/* Clock type, used to tell common block what it's part of */ +enum bcm_clk_type { + bcm_clk_none, /* undefined clock type */ + bcm_clk_bus, + bcm_clk_core, + bcm_clk_peri +}; + +/* + * Each CCU defines a mapped area of memory containing registers + * used to manage clocks implemented by the CCU. Access to memory + * within the CCU's space is serialized by a spinlock. Before any + * (other) address can be written, a special access "password" value + * must be written to its WR_ACCESS register (located at the base + * address of the range). We keep track of the name of each CCU as + * it is set up, and maintain them in a list. + */ +struct ccu_data { + void __iomem *base; /* base of mapped address space */ + spinlock_t lock; /* serialization lock */ + bool write_enabled; /* write access is currently enabled */ + struct list_head links; /* for ccu_list */ + struct device_node *node; + struct clk_onecell_data data; + const char *name; + u32 range; /* byte range of address space */ +}; + +/* + * Gating control and status is managed by a 32-bit gate register. + * + * There are several types of gating available: + * - (no gate) + * A clock with no gate is assumed to be always enabled. + * - hardware-only gating (auto-gating) + * Enabling or disabling clocks with this type of gate is + * managed automatically by the hardware. Such clocks can be + * considered by the software to be enabled. The current status + * of auto-gated clocks can be read from the gate status bit. + * - software-only gating + * Auto-gating is not available for this type of clock. + * Instead, software manages whether it's enabled by setting or + * clearing the enable bit. The current gate status of a gate + * under software control can be read from the gate status bit. + * To ensure a change to the gating status is complete, the + * status bit can be polled to verify that the gate has entered + * the desired state. + * - selectable hardware or software gating + * Gating for this type of clock can be configured to be either + * under software or hardware control. Which type is in use is + * determined by the hw_sw_sel bit of the gate register. + */ +struct bcm_clk_gate { + u32 offset; /* gate register offset */ + u32 status_bit; /* 0: gate is disabled; 0: gatge is enabled */ + u32 en_bit; /* 0: disable; 1: enable */ + u32 hw_sw_sel_bit; /* 0: hardware gating; 1: software gating */ + u32 flags; /* BCM_CLK_GATE_FLAGS_* below */ +}; + +/* + * Gate flags: + * HW means this gate can be auto-gated + * SW means the state of this gate can be software controlled + * NO_DISABLE means this gate is (only) enabled if under software control + * SW_MANAGED means the status of this gate is under software control + * ENABLED means this software-managed gate is *supposed* to be enabled + */ +#define BCM_CLK_GATE_FLAGS_EXISTS ((u32)1 << 0) /* Gate is valid */ +#define BCM_CLK_GATE_FLAGS_HW ((u32)1 << 1) /* Can auto-gate */ +#define BCM_CLK_GATE_FLAGS_SW ((u32)1 << 2) /* Software control */ +#define BCM_CLK_GATE_FLAGS_NO_DISABLE ((u32)1 << 3) /* HW or enabled */ +#define BCM_CLK_GATE_FLAGS_SW_MANAGED ((u32)1 << 4) /* SW now in control */ +#define BCM_CLK_GATE_FLAGS_ENABLED ((u32)1 << 5) /* If SW_MANAGED */ + +/* + * Gate initialization macros. + * + * Any gate initially under software control will be enabled. + */ + +/* A hardware/software gate initially under software control */ +#define HW_SW_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \ + { \ + .offset = (_offset), \ + .status_bit = (_status_bit), \ + .en_bit = (_en_bit), \ + .hw_sw_sel_bit = (_hw_sw_sel_bit), \ + .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \ + FLAG(GATE, SW_MANAGED)|FLAG(GATE, ENABLED)| \ + FLAG(GATE, EXISTS), \ + } + +/* A hardware/software gate initially under hardware control */ +#define HW_SW_GATE_AUTO(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \ + { \ + .offset = (_offset), \ + .status_bit = (_status_bit), \ + .en_bit = (_en_bit), \ + .hw_sw_sel_bit = (_hw_sw_sel_bit), \ + .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \ + FLAG(GATE, EXISTS), \ + } + +/* A hardware-or-enabled gate (enabled if not under hardware control) */ +#define HW_ENABLE_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \ + { \ + .offset = (_offset), \ + .status_bit = (_status_bit), \ + .en_bit = (_en_bit), \ + .hw_sw_sel_bit = (_hw_sw_sel_bit), \ + .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \ + FLAG(GATE, NO_DISABLE)|FLAG(GATE, EXISTS), \ + } + +/* A software-only gate */ +#define SW_ONLY_GATE(_offset, _status_bit, _en_bit) \ + { \ + .offset = (_offset), \ + .status_bit = (_status_bit), \ + .en_bit = (_en_bit), \ + .flags = FLAG(GATE, SW)|FLAG(GATE, SW_MANAGED)| \ + FLAG(GATE, ENABLED)|FLAG(GATE, EXISTS), \ + } + +/* A hardware-only gate */ +#define HW_ONLY_GATE(_offset, _status_bit) \ + { \ + .offset = (_offset), \ + .status_bit = (_status_bit), \ + .flags = FLAG(GATE, HW)|FLAG(GATE, EXISTS), \ + } + +/* + * Each clock can have zero, one, or two dividers which change the + * output rate of the clock. Each divider can be either fixed or + * variable. If there are two dividers, they are the "pre-divider" + * and the "regular" or "downstream" divider. If there is only one, + * there is no pre-divider. + * + * A fixed divider is any non-zero (positive) value, and it + * indicates how the input rate is affected by the divider. + * + * The value of a variable divider is maintained in a sub-field of a + * 32-bit divider register. The position of the field in the + * register is defined by its offset and width. The value recorded + * in this field is always 1 less than the value it represents. + * + * In addition, a variable divider can indicate that some subset + * of its bits represent a "fractional" part of the divider. Such + * bits comprise the low-order portion of the divider field, and can + * be viewed as representing the portion of the divider that lies to + * the right of the decimal point. Most variable dividers have zero + * fractional bits. Variable dividers with non-zero fraction width + * still record a value 1 less than the value they represent; the + * added 1 does *not* affect the low-order bit in this case, it + * affects the bits above the fractional part only. (Often in this + * code a divider field value is distinguished from the value it + * represents by referring to the latter as a "divisor".) + * + * In order to avoid dealing with fractions, divider arithmetic is + * performed using "scaled" values. A scaled value is one that's + * been left-shifted by the fractional width of a divider. Dividing + * a scaled value by a scaled divisor produces the desired quotient + * without loss of precision and without any other special handling + * for fractions. + * + * The recorded value of a variable divider can be modified. To + * modify either divider (or both), a clock must be enabled (i.e., + * using its gate). In addition, a trigger register (described + * below) must be used to commit the change, and polled to verify + * the change is complete. + */ +struct bcm_clk_div { + union { + struct { /* variable divider */ + u32 offset; /* divider register offset */ + u32 shift; /* field shift */ + u32 width; /* field width */ + u32 frac_width; /* field fraction width */ + + u64 scaled_div; /* scaled divider value */ + }; + u32 fixed; /* non-zero fixed divider value */ + }; + u32 flags; /* BCM_CLK_DIV_FLAGS_* below */ +}; + +/* + * Divider flags: + * EXISTS means this divider exists + * FIXED means it is a fixed-rate divider + */ +#define BCM_CLK_DIV_FLAGS_EXISTS ((u32)1 << 0) /* Divider is valid */ +#define BCM_CLK_DIV_FLAGS_FIXED ((u32)1 << 1) /* Fixed-value */ + +/* Divider initialization macros */ + +/* A fixed (non-zero) divider */ +#define FIXED_DIVIDER(_value) \ + { \ + .fixed = (_value), \ + .flags = FLAG(DIV, EXISTS)|FLAG(DIV, FIXED), \ + } + +/* A divider with an integral divisor */ +#define DIVIDER(_offset, _shift, _width) \ + { \ + .offset = (_offset), \ + .shift = (_shift), \ + .width = (_width), \ + .scaled_div = BAD_SCALED_DIV_VALUE, \ + .flags = FLAG(DIV, EXISTS), \ + } + +/* A divider whose divisor has an integer and fractional part */ +#define FRAC_DIVIDER(_offset, _shift, _width, _frac_width) \ + { \ + .offset = (_offset), \ + .shift = (_shift), \ + .width = (_width), \ + .frac_width = (_frac_width), \ + .scaled_div = BAD_SCALED_DIV_VALUE, \ + .flags = FLAG(DIV, EXISTS), \ + } + +/* + * Clocks may have multiple "parent" clocks. If there is more than + * one, a selector must be specified to define which of the parent + * clocks is currently in use. The selected clock is indicated in a + * sub-field of a 32-bit selector register. The range of + * representable selector values typically exceeds the number of + * available parent clocks. Occasionally the reset value of a + * selector field is explicitly set to a (specific) value that does + * not correspond to a defined input clock. + * + * We register all known parent clocks with the common clock code + * using a packed array (i.e., no empty slots) of (parent) clock + * names, and refer to them later using indexes into that array. + * We maintain an array of selector values indexed by common clock + * index values in order to map between these common clock indexes + * and the selector values used by the hardware. + * + * Like dividers, a selector can be modified, but to do so a clock + * must be enabled, and a trigger must be used to commit the change. + */ +struct bcm_clk_sel { + u32 offset; /* selector register offset */ + u32 shift; /* field shift */ + u32 width; /* field width */ + + u32 parent_count; /* number of entries in parent_sel[] */ + u32 *parent_sel; /* array of parent selector values */ + u8 clk_index; /* current selected index in parent_sel[] */ +}; + +/* Selector initialization macro */ +#define SELECTOR(_offset, _shift, _width) \ + { \ + .offset = (_offset), \ + .shift = (_shift), \ + .width = (_width), \ + .clk_index = BAD_CLK_INDEX, \ + } + +/* + * Making changes to a variable divider or a selector for a clock + * requires the use of a trigger. A trigger is defined by a single + * bit within a register. To signal a change, a 1 is written into + * that bit. To determine when the change has been completed, that + * trigger bit is polled; the read value will be 1 while the change + * is in progress, and 0 when it is complete. + * + * Occasionally a clock will have more than one trigger. In this + * case, the "pre-trigger" will be used when changing a clock's + * selector and/or its pre-divider. + */ +struct bcm_clk_trig { + u32 offset; /* trigger register offset */ + u32 bit; /* trigger bit */ + u32 flags; /* BCM_CLK_TRIG_FLAGS_* below */ +}; + +/* + * Trigger flags: + * EXISTS means this trigger exists + */ +#define BCM_CLK_TRIG_FLAGS_EXISTS ((u32)1 << 0) /* Trigger is valid */ + +/* Trigger initialization macro */ +#define TRIGGER(_offset, _bit) \ + { \ + .offset = (_offset), \ + .bit = (_bit), \ + .flags = FLAG(TRIG, EXISTS), \ + } + +struct peri_clk_data { + struct bcm_clk_gate gate; + struct bcm_clk_trig pre_trig; + struct bcm_clk_div pre_div; + struct bcm_clk_trig trig; + struct bcm_clk_div div; + struct bcm_clk_sel sel; + const char *clocks[]; /* must be last; use CLOCKS() to declare */ +}; +#define CLOCKS(...) { __VA_ARGS__, NULL, } +#define NO_CLOCKS { NULL, } /* Must use of no parent clocks */ + +struct kona_clk { + struct clk_hw hw; + struct clk_init_data init_data; + const char *name; /* name of this clock */ + struct ccu_data *ccu; /* ccu this clock is associated with */ + enum bcm_clk_type type; + union { + void *data; + struct peri_clk_data *peri; + }; +}; +#define to_kona_clk(_hw) \ + container_of(_hw, struct kona_clk, hw) + +/* Exported globals */ + +extern struct clk_ops kona_peri_clk_ops; + +/* Help functions */ + +#define PERI_CLK_SETUP(clks, ccu, id, name) \ + clks[id] = kona_clk_setup(ccu, #name, bcm_clk_peri, &name ## _data) + +/* Externally visible functions */ + +extern u64 do_div_round_closest(u64 dividend, unsigned long divisor); +extern u64 scaled_div_max(struct bcm_clk_div *div); +extern u64 scaled_div_build(struct bcm_clk_div *div, u32 div_value, + u32 billionths); + +extern struct clk *kona_clk_setup(struct ccu_data *ccu, const char *name, + enum bcm_clk_type type, void *data); +extern void __init kona_dt_ccu_setup(struct device_node *node, + int (*ccu_clks_setup)(struct ccu_data *)); +extern bool __init kona_ccu_init(struct ccu_data *ccu); + +#endif /* _CLK_KONA_H */ |