diff options
| -rw-r--r-- | arch/arm/mach-ep93xx/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm/mach-ep93xx/clock.c | 156 | ||||
| -rw-r--r-- | arch/arm/mach-ep93xx/core.c | 2 | ||||
| -rw-r--r-- | include/asm-arm/arch-ep93xx/ep93xx-regs.h | 2 | ||||
| -rw-r--r-- | include/asm-arm/arch-ep93xx/platform.h | 1 |
5 files changed, 162 insertions, 1 deletions
diff --git a/arch/arm/mach-ep93xx/Makefile b/arch/arm/mach-ep93xx/Makefile index 5393af989e9..05a48a21038 100644 --- a/arch/arm/mach-ep93xx/Makefile +++ b/arch/arm/mach-ep93xx/Makefile @@ -1,7 +1,7 @@ # # Makefile for the linux kernel. # -obj-y := core.o +obj-y := core.o clock.o obj-m := obj-n := obj- := diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c new file mode 100644 index 00000000000..08ad782c164 --- /dev/null +++ b/arch/arm/mach-ep93xx/clock.c @@ -0,0 +1,156 @@ +/* + * arch/arm/mach-ep93xx/clock.c + * Clock control for Cirrus EP93xx chips. + * + * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> + * + * 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; either version 2 of the License, or (at + * your option) any later version. + */ + +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/string.h> +#include <asm/div64.h> +#include <asm/hardware.h> +#include <asm/io.h> + +struct clk { + char *name; + unsigned long rate; + int users; + u32 enable_reg; + u32 enable_mask; +}; + +static struct clk clk_pll1 = { + .name = "pll1", +}; +static struct clk clk_f = { + .name = "fclk", +}; +static struct clk clk_h = { + .name = "hclk", +}; +static struct clk clk_p = { + .name = "pclk", +}; +static struct clk clk_pll2 = { + .name = "pll2", +}; +static struct clk clk_usb_host = { + .name = "usb_host", + .enable_reg = EP93XX_SYSCON_CLOCK_CONTROL, + .enable_mask = EP93XX_SYSCON_CLOCK_USH_EN, +}; + + +static struct clk *clocks[] = { + &clk_pll1, + &clk_f, + &clk_h, + &clk_p, + &clk_pll2, + &clk_usb_host, +}; + +struct clk *clk_get(struct device *dev, const char *id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(clocks); i++) { + if (!strcmp(clocks[i]->name, id)) + return clocks[i]; + } + + return ERR_PTR(-ENOENT); +} + +int clk_enable(struct clk *clk) +{ + if (!clk->users++ && clk->enable_reg) { + u32 value; + + value = __raw_readl(clk->enable_reg); + __raw_writel(value | clk->enable_mask, clk->enable_reg); + } + + return 0; +} + +void clk_disable(struct clk *clk) +{ + if (!--clk->users && clk->enable_reg) { + u32 value; + + value = __raw_readl(clk->enable_reg); + __raw_writel(value & ~clk->enable_mask, clk->enable_reg); + } +} + +unsigned long clk_get_rate(struct clk *clk) +{ + return clk->rate; +} + +void clk_put(struct clk *clk) +{ +} + + + +static char fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 }; +static char hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 }; +static char pclk_divisors[] = { 1, 2, 4, 8 }; + +/* + * PLL rate = 14.7456 MHz * (X1FBD + 1) * (X2FBD + 1) / (X2IPD + 1) / 2^PS + */ +static unsigned long calc_pll_rate(u32 config_word) +{ + unsigned long long rate; + int i; + + rate = 14745600; + rate *= ((config_word >> 11) & 0x1f) + 1; /* X1FBD */ + rate *= ((config_word >> 5) & 0x3f) + 1; /* X2FBD */ + do_div(rate, (config_word & 0x1f) + 1); /* X2IPD */ + for (i = 0; i < ((config_word >> 16) & 3); i++) /* PS */ + rate >>= 1; + + return (unsigned long)rate; +} + +void ep93xx_clock_init(void) +{ + u32 value; + + value = __raw_readl(EP93XX_SYSCON_CLOCK_SET1); + if (!(value & 0x00800000)) { /* PLL1 bypassed? */ + clk_pll1.rate = 14745600; + } else { + clk_pll1.rate = calc_pll_rate(value); + } + clk_f.rate = clk_pll1.rate / fclk_divisors[(value >> 25) & 0x7]; + clk_h.rate = clk_pll1.rate / hclk_divisors[(value >> 20) & 0x7]; + clk_p.rate = clk_h.rate / pclk_divisors[(value >> 18) & 0x3]; + + value = __raw_readl(EP93XX_SYSCON_CLOCK_SET2); + if (!(value & 0x00080000)) { /* PLL2 bypassed? */ + clk_pll2.rate = 14745600; + } else if (value & 0x00040000) { /* PLL2 enabled? */ + clk_pll2.rate = calc_pll_rate(value); + } else { + clk_pll2.rate = 0; + } + clk_usb_host.rate = clk_pll2.rate / (((value >> 28) & 0xf) + 1); + + printk(KERN_INFO "ep93xx: PLL1 running at %ld MHz, PLL2 at %ld MHz\n", + clk_pll1.rate / 1000000, clk_pll2.rate / 1000000); + printk(KERN_INFO "ep93xx: FCLK %ld MHz, HCLK %ld MHz, PCLK %ld MHz\n", + clk_f.rate / 1000000, clk_h.rate / 1000000, + clk_p.rate / 1000000); +} diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c index bf6bd71bdd0..6fd6aa74a1f 100644 --- a/arch/arm/mach-ep93xx/core.c +++ b/arch/arm/mach-ep93xx/core.c @@ -437,6 +437,8 @@ void __init ep93xx_init_devices(void) { unsigned int v; + ep93xx_clock_init(); + /* * Disallow access to MaverickCrunch initially. */ diff --git a/include/asm-arm/arch-ep93xx/ep93xx-regs.h b/include/asm-arm/arch-ep93xx/ep93xx-regs.h index 71cea0b5841..8c322975f96 100644 --- a/include/asm-arm/arch-ep93xx/ep93xx-regs.h +++ b/include/asm-arm/arch-ep93xx/ep93xx-regs.h @@ -115,6 +115,8 @@ #define EP93XX_SYSCON_CLOCK_USH_EN 0x10000000 #define EP93XX_SYSCON_HALT EP93XX_SYSCON_REG(0x08) #define EP93XX_SYSCON_STANDBY EP93XX_SYSCON_REG(0x0c) +#define EP93XX_SYSCON_CLOCK_SET1 EP93XX_SYSCON_REG(0x20) +#define EP93XX_SYSCON_CLOCK_SET2 EP93XX_SYSCON_REG(0x24) #define EP93XX_SYSCON_DEVICE_CONFIG EP93XX_SYSCON_REG(0x80) #define EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE 0x00800000 #define EP93XX_SYSCON_SWLOCK EP93XX_SYSCON_REG(0xc0) diff --git a/include/asm-arm/arch-ep93xx/platform.h b/include/asm-arm/arch-ep93xx/platform.h index df9cbb6ef66..d7a34ce2029 100644 --- a/include/asm-arm/arch-ep93xx/platform.h +++ b/include/asm-arm/arch-ep93xx/platform.h @@ -8,6 +8,7 @@ void ep93xx_map_io(void); void ep93xx_init_irq(void); void ep93xx_init_time(unsigned long); void ep93xx_init_devices(void); +void ep93xx_clock_init(void); extern struct sys_timer ep93xx_timer; |