diff options
| -rw-r--r-- | Documentation/devicetree/bindings/clock/mvebu-cpu-clock.txt | 5 | ||||
| -rw-r--r-- | arch/arm/mach-mvebu/platsmp.c | 1 | ||||
| -rw-r--r-- | arch/arm/mach-mvebu/pmsu.c | 162 | ||||
| -rw-r--r-- | drivers/clk/mvebu/clk-cpu.c | 80 | ||||
| -rw-r--r-- | include/linux/mvebu-pmsu.h | 20 |
5 files changed, 261 insertions, 7 deletions
diff --git a/Documentation/devicetree/bindings/clock/mvebu-cpu-clock.txt b/Documentation/devicetree/bindings/clock/mvebu-cpu-clock.txt index feb83013071..99c214660bd 100644 --- a/Documentation/devicetree/bindings/clock/mvebu-cpu-clock.txt +++ b/Documentation/devicetree/bindings/clock/mvebu-cpu-clock.txt @@ -3,14 +3,15 @@ Device Tree Clock bindings for cpu clock of Marvell EBU platforms Required properties: - compatible : shall be one of the following: "marvell,armada-xp-cpu-clock" - cpu clocks for Armada XP -- reg : Address and length of the clock complex register set +- reg : Address and length of the clock complex register set, followed + by address and length of the PMU DFS registers - #clock-cells : should be set to 1. - clocks : shall be the input parent clock phandle for the clock. cpuclk: clock-complex@d0018700 { #clock-cells = <1>; compatible = "marvell,armada-xp-cpu-clock"; - reg = <0xd0018700 0xA0>; + reg = <0xd0018700 0xA0>, <0x1c054 0x10>; clocks = <&coreclk 1>; } diff --git a/arch/arm/mach-mvebu/platsmp.c b/arch/arm/mach-mvebu/platsmp.c index 6da2b723d37..895dc373c8a 100644 --- a/arch/arm/mach-mvebu/platsmp.c +++ b/arch/arm/mach-mvebu/platsmp.c @@ -67,6 +67,7 @@ static void __init set_secondary_cpus_clock(void) if (!cpu_clk) return; clk_set_rate(cpu_clk, rate); + clk_prepare_enable(cpu_clk); } } diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c index bd7c66a2882..8a70a51533f 100644 --- a/arch/arm/mach-mvebu/pmsu.c +++ b/arch/arm/mach-mvebu/pmsu.c @@ -18,14 +18,19 @@ #define pr_fmt(fmt) "mvebu-pmsu: " fmt +#include <linux/clk.h> #include <linux/cpu_pm.h> +#include <linux/delay.h> #include <linux/init.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/mbus.h> #include <linux/of_address.h> +#include <linux/of_device.h> #include <linux/platform_device.h> +#include <linux/pm_opp.h> #include <linux/resource.h> +#include <linux/slab.h> #include <linux/smp.h> #include <asm/cacheflush.h> #include <asm/cp15.h> @@ -34,6 +39,7 @@ #include <asm/suspend.h> #include <asm/tlbflush.h> #include "common.h" +#include "armada-370-xp.h" #define PMSU_BASE_OFFSET 0x100 @@ -58,6 +64,10 @@ #define PMSU_STATUS_AND_MASK_IRQ_MASK BIT(24) #define PMSU_STATUS_AND_MASK_FIQ_MASK BIT(25) +#define PMSU_EVENT_STATUS_AND_MASK(cpu) ((cpu * 0x100) + 0x120) +#define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE BIT(1) +#define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK BIT(17) + #define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124) /* PMSU fabric registers */ @@ -487,3 +497,155 @@ static int __init mvebu_v7_cpu_pm_init(void) arch_initcall(mvebu_v7_cpu_pm_init); early_initcall(mvebu_v7_pmsu_init); + +static void mvebu_pmsu_dfs_request_local(void *data) +{ + u32 reg; + u32 cpu = smp_processor_id(); + unsigned long flags; + + local_irq_save(flags); + + /* Prepare to enter idle */ + reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu)); + reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT | + PMSU_STATUS_AND_MASK_IRQ_MASK | + PMSU_STATUS_AND_MASK_FIQ_MASK; + writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu)); + + /* Request the DFS transition */ + reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu)); + reg |= PMSU_CONTROL_AND_CONFIG_DFS_REQ; + writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu)); + + /* The fact of entering idle will trigger the DFS transition */ + wfi(); + + /* + * We're back from idle, the DFS transition has completed, + * clear the idle wait indication. + */ + reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu)); + reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT; + writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu)); + + local_irq_restore(flags); +} + +int mvebu_pmsu_dfs_request(int cpu) +{ + unsigned long timeout; + int hwcpu = cpu_logical_map(cpu); + u32 reg; + + /* Clear any previous DFS DONE event */ + reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu)); + reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE; + writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu)); + + /* Mask the DFS done interrupt, since we are going to poll */ + reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu)); + reg |= PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK; + writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu)); + + /* Trigger the DFS on the appropriate CPU */ + smp_call_function_single(cpu, mvebu_pmsu_dfs_request_local, + NULL, false); + + /* Poll until the DFS done event is generated */ + timeout = jiffies + HZ; + while (time_before(jiffies, timeout)) { + reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu)); + if (reg & PMSU_EVENT_STATUS_AND_MASK_DFS_DONE) + break; + udelay(10); + } + + if (time_after(jiffies, timeout)) + return -ETIME; + + /* Restore the DFS mask to its original state */ + reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu)); + reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK; + writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu)); + + return 0; +} + +static int __init armada_xp_pmsu_cpufreq_init(void) +{ + struct device_node *np; + struct resource res; + int ret, cpu; + + if (!of_machine_is_compatible("marvell,armadaxp")) + return 0; + + /* + * In order to have proper cpufreq handling, we need to ensure + * that the Device Tree description of the CPU clock includes + * the definition of the PMU DFS registers. If not, we do not + * register the clock notifier and the cpufreq driver. This + * piece of code is only for compatibility with old Device + * Trees. + */ + np = of_find_compatible_node(NULL, NULL, "marvell,armada-xp-cpu-clock"); + if (!np) + return 0; + + ret = of_address_to_resource(np, 1, &res); + if (ret) { + pr_warn(FW_WARN "not enabling cpufreq, deprecated armada-xp-cpu-clock binding\n"); + of_node_put(np); + return 0; + } + + of_node_put(np); + + /* + * For each CPU, this loop registers the operating points + * supported (which are the nominal CPU frequency and half of + * it), and registers the clock notifier that will take care + * of doing the PMSU part of a frequency transition. + */ + for_each_possible_cpu(cpu) { + struct device *cpu_dev; + struct clk *clk; + int ret; + + cpu_dev = get_cpu_device(cpu); + if (!cpu_dev) { + pr_err("Cannot get CPU %d\n", cpu); + continue; + } + + clk = clk_get(cpu_dev, 0); + if (IS_ERR(clk)) { + pr_err("Cannot get clock for CPU %d\n", cpu); + return PTR_ERR(clk); + } + + /* + * In case of a failure of dev_pm_opp_add(), we don't + * bother with cleaning up the registered OPP (there's + * no function to do so), and simply cancel the + * registration of the cpufreq device. + */ + ret = dev_pm_opp_add(cpu_dev, clk_get_rate(clk), 0); + if (ret) { + clk_put(clk); + return ret; + } + + ret = dev_pm_opp_add(cpu_dev, clk_get_rate(clk) / 2, 0); + if (ret) { + clk_put(clk); + return ret; + } + } + + platform_device_register_simple("cpufreq-generic", -1, NULL, 0); + return 0; +} + +device_initcall(armada_xp_pmsu_cpufreq_init); diff --git a/drivers/clk/mvebu/clk-cpu.c b/drivers/clk/mvebu/clk-cpu.c index 8ebf757d29e..3821a88077e 100644 --- a/drivers/clk/mvebu/clk-cpu.c +++ b/drivers/clk/mvebu/clk-cpu.c @@ -16,10 +16,19 @@ #include <linux/io.h> #include <linux/of.h> #include <linux/delay.h> +#include <linux/mvebu-pmsu.h> +#include <asm/smp_plat.h> -#define SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET 0x0 -#define SYS_CTRL_CLK_DIVIDER_VALUE_OFFSET 0xC -#define SYS_CTRL_CLK_DIVIDER_MASK 0x3F +#define SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET 0x0 +#define SYS_CTRL_CLK_DIVIDER_CTRL_RESET_ALL 0xff +#define SYS_CTRL_CLK_DIVIDER_CTRL_RESET_SHIFT 8 +#define SYS_CTRL_CLK_DIVIDER_CTRL2_OFFSET 0x8 +#define SYS_CTRL_CLK_DIVIDER_CTRL2_NBCLK_RATIO_SHIFT 16 +#define SYS_CTRL_CLK_DIVIDER_VALUE_OFFSET 0xC +#define SYS_CTRL_CLK_DIVIDER_MASK 0x3F + +#define PMU_DFS_RATIO_SHIFT 16 +#define PMU_DFS_RATIO_MASK 0x3F #define MAX_CPU 4 struct cpu_clk { @@ -28,6 +37,7 @@ struct cpu_clk { const char *clk_name; const char *parent_name; void __iomem *reg_base; + void __iomem *pmu_dfs; }; static struct clk **clks; @@ -62,8 +72,9 @@ static long clk_cpu_round_rate(struct clk_hw *hwclk, unsigned long rate, return *parent_rate / div; } -static int clk_cpu_set_rate(struct clk_hw *hwclk, unsigned long rate, - unsigned long parent_rate) +static int clk_cpu_off_set_rate(struct clk_hw *hwclk, unsigned long rate, + unsigned long parent_rate) + { struct cpu_clk *cpuclk = to_cpu_clk(hwclk); u32 reg, div; @@ -95,6 +106,58 @@ static int clk_cpu_set_rate(struct clk_hw *hwclk, unsigned long rate, return 0; } +static int clk_cpu_on_set_rate(struct clk_hw *hwclk, unsigned long rate, + unsigned long parent_rate) +{ + u32 reg; + unsigned long fabric_div, target_div, cur_rate; + struct cpu_clk *cpuclk = to_cpu_clk(hwclk); + + /* + * PMU DFS registers are not mapped, Device Tree does not + * describes them. We cannot change the frequency dynamically. + */ + if (!cpuclk->pmu_dfs) + return -ENODEV; + + cur_rate = __clk_get_rate(hwclk->clk); + + reg = readl(cpuclk->reg_base + SYS_CTRL_CLK_DIVIDER_CTRL2_OFFSET); + fabric_div = (reg >> SYS_CTRL_CLK_DIVIDER_CTRL2_NBCLK_RATIO_SHIFT) & + SYS_CTRL_CLK_DIVIDER_MASK; + + /* Frequency is going up */ + if (rate == 2 * cur_rate) + target_div = fabric_div / 2; + /* Frequency is going down */ + else + target_div = fabric_div; + + if (target_div == 0) + target_div = 1; + + reg = readl(cpuclk->pmu_dfs); + reg &= ~(PMU_DFS_RATIO_MASK << PMU_DFS_RATIO_SHIFT); + reg |= (target_div << PMU_DFS_RATIO_SHIFT); + writel(reg, cpuclk->pmu_dfs); + + reg = readl(cpuclk->reg_base + SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET); + reg |= (SYS_CTRL_CLK_DIVIDER_CTRL_RESET_ALL << + SYS_CTRL_CLK_DIVIDER_CTRL_RESET_SHIFT); + writel(reg, cpuclk->reg_base + SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET); + + return mvebu_pmsu_dfs_request(cpuclk->cpu); +} + +static int clk_cpu_set_rate(struct clk_hw *hwclk, unsigned long rate, + unsigned long parent_rate) +{ + if (__clk_is_enabled(hwclk->clk)) + return clk_cpu_on_set_rate(hwclk, rate, parent_rate); + else + return clk_cpu_off_set_rate(hwclk, rate, parent_rate); +} + static const struct clk_ops cpu_ops = { .recalc_rate = clk_cpu_recalc_rate, .round_rate = clk_cpu_round_rate, @@ -105,6 +168,7 @@ static void __init of_cpu_clk_setup(struct device_node *node) { struct cpu_clk *cpuclk; void __iomem *clock_complex_base = of_iomap(node, 0); + void __iomem *pmu_dfs_base = of_iomap(node, 1); int ncpus = 0; struct device_node *dn; @@ -114,6 +178,10 @@ static void __init of_cpu_clk_setup(struct device_node *node) return; } + if (pmu_dfs_base == NULL) + pr_warn("%s: pmu-dfs base register not set, dynamic frequency scaling not available\n", + __func__); + for_each_node_by_type(dn, "cpu") ncpus++; @@ -146,6 +214,8 @@ static void __init of_cpu_clk_setup(struct device_node *node) cpuclk[cpu].clk_name = clk_name; cpuclk[cpu].cpu = cpu; cpuclk[cpu].reg_base = clock_complex_base; + if (pmu_dfs_base) + cpuclk[cpu].pmu_dfs = pmu_dfs_base + 4 * cpu; cpuclk[cpu].hw.init = &init; init.name = cpuclk[cpu].clk_name; diff --git a/include/linux/mvebu-pmsu.h b/include/linux/mvebu-pmsu.h new file mode 100644 index 00000000000..b918d07efe2 --- /dev/null +++ b/include/linux/mvebu-pmsu.h @@ -0,0 +1,20 @@ +/* + * Copyright (C) 2012 Marvell + * + * Thomas Petazzoni <thomas.petazzoni@free-electrons.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#ifndef __MVEBU_PMSU_H__ +#define __MVEBU_PMSU_H__ + +#ifdef CONFIG_MACH_MVEBU_V7 +int mvebu_pmsu_dfs_request(int cpu); +#else +static inline int mvebu_pmsu_dfs_request(int cpu) { return -ENODEV; } +#endif + +#endif /* __MVEBU_PMSU_H__ */ |