diff options
Diffstat (limited to 'arch/arm/mach-s3c2410/clock.c')
-rw-r--r-- | arch/arm/mach-s3c2410/clock.c | 565 |
1 files changed, 196 insertions, 369 deletions
diff --git a/arch/arm/mach-s3c2410/clock.c b/arch/arm/mach-s3c2410/clock.c index e13fb677889..5b4831c4c1d 100644 --- a/arch/arm/mach-s3c2410/clock.c +++ b/arch/arm/mach-s3c2410/clock.c @@ -1,15 +1,9 @@ /* linux/arch/arm/mach-s3c2410/clock.c * - * Copyright (c) 2004-2005 Simtec Electronics + * Copyright (c) 2006 Simtec Electronics * Ben Dooks <ben@simtec.co.uk> * - * S3C24XX Core clock control support - * - * Based on, and code from linux/arch/arm/mach-versatile/clock.c - ** - ** Copyright (C) 2004 ARM Limited. - ** Written by Deep Blue Solutions Limited. - * + * S3C2410,S3C2440,S3C2442 Clock control support * * 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 @@ -32,418 +26,251 @@ #include <linux/list.h> #include <linux/errno.h> #include <linux/err.h> -#include <linux/platform_device.h> #include <linux/sysdev.h> -#include <linux/interrupt.h> -#include <linux/ioport.h> #include <linux/clk.h> #include <linux/mutex.h> #include <linux/delay.h> +#include <linux/serial_core.h> + +#include <asm/mach/map.h> #include <asm/hardware.h> -#include <asm/irq.h> #include <asm/io.h> +#include <asm/arch/regs-serial.h> #include <asm/arch/regs-clock.h> #include <asm/arch/regs-gpio.h> -#include "clock.h" -#include "cpu.h" - -/* clock information */ +#include <asm/plat-s3c24xx/s3c2410.h> +#include <asm/plat-s3c24xx/clock.h> +#include <asm/plat-s3c24xx/cpu.h> -static LIST_HEAD(clocks); - -DEFINE_MUTEX(clocks_mutex); - -/* enable and disable calls for use with the clk struct */ - -static int clk_null_enable(struct clk *clk, int enable) +int s3c2410_clkcon_enable(struct clk *clk, int enable) { - return 0; -} - -/* Clock API calls */ + unsigned int clocks = clk->ctrlbit; + unsigned long clkcon; -struct clk *clk_get(struct device *dev, const char *id) -{ - struct clk *p; - struct clk *clk = ERR_PTR(-ENOENT); - int idno; + clkcon = __raw_readl(S3C2410_CLKCON); - if (dev == NULL || dev->bus != &platform_bus_type) - idno = -1; + if (enable) + clkcon |= clocks; else - idno = to_platform_device(dev)->id; - - mutex_lock(&clocks_mutex); - - list_for_each_entry(p, &clocks, list) { - if (p->id == idno && - strcmp(id, p->name) == 0 && - try_module_get(p->owner)) { - clk = p; - break; - } - } - - /* check for the case where a device was supplied, but the - * clock that was being searched for is not device specific */ - - if (IS_ERR(clk)) { - list_for_each_entry(p, &clocks, list) { - if (p->id == -1 && strcmp(id, p->name) == 0 && - try_module_get(p->owner)) { - clk = p; - break; - } - } - } + clkcon &= ~clocks; - mutex_unlock(&clocks_mutex); - return clk; -} + /* ensure none of the special function bits set */ + clkcon &= ~(S3C2410_CLKCON_IDLE|S3C2410_CLKCON_POWER); -void clk_put(struct clk *clk) -{ - module_put(clk->owner); -} + __raw_writel(clkcon, S3C2410_CLKCON); -int clk_enable(struct clk *clk) -{ - if (IS_ERR(clk) || clk == NULL) - return -EINVAL; - - clk_enable(clk->parent); - - mutex_lock(&clocks_mutex); - - if ((clk->usage++) == 0) - (clk->enable)(clk, 1); - - mutex_unlock(&clocks_mutex); return 0; } -void clk_disable(struct clk *clk) -{ - if (IS_ERR(clk) || clk == NULL) - return; - - mutex_lock(&clocks_mutex); - - if ((--clk->usage) == 0) - (clk->enable)(clk, 0); - - mutex_unlock(&clocks_mutex); - clk_disable(clk->parent); -} - - -unsigned long clk_get_rate(struct clk *clk) -{ - if (IS_ERR(clk)) - return 0; - - if (clk->rate != 0) - return clk->rate; - - if (clk->get_rate != NULL) - return (clk->get_rate)(clk); - - if (clk->parent != NULL) - return clk_get_rate(clk->parent); - - return clk->rate; -} - -long clk_round_rate(struct clk *clk, unsigned long rate) -{ - if (!IS_ERR(clk) && clk->round_rate) - return (clk->round_rate)(clk, rate); - - return rate; -} - -int clk_set_rate(struct clk *clk, unsigned long rate) -{ - int ret; - - if (IS_ERR(clk)) - return -EINVAL; - - mutex_lock(&clocks_mutex); - ret = (clk->set_rate)(clk, rate); - mutex_unlock(&clocks_mutex); - - return ret; -} - -struct clk *clk_get_parent(struct clk *clk) +static int s3c2410_upll_enable(struct clk *clk, int enable) { - return clk->parent; -} - -int clk_set_parent(struct clk *clk, struct clk *parent) -{ - int ret = 0; - - if (IS_ERR(clk)) - return -EINVAL; - - mutex_lock(&clocks_mutex); - - if (clk->set_parent) - ret = (clk->set_parent)(clk, parent); - - mutex_unlock(&clocks_mutex); - - return ret; -} - -EXPORT_SYMBOL(clk_get); -EXPORT_SYMBOL(clk_put); -EXPORT_SYMBOL(clk_enable); -EXPORT_SYMBOL(clk_disable); -EXPORT_SYMBOL(clk_get_rate); -EXPORT_SYMBOL(clk_round_rate); -EXPORT_SYMBOL(clk_set_rate); -EXPORT_SYMBOL(clk_get_parent); -EXPORT_SYMBOL(clk_set_parent); - -/* base clocks */ - -struct clk clk_xtal = { - .name = "xtal", - .id = -1, - .rate = 0, - .parent = NULL, - .ctrlbit = 0, -}; - -struct clk clk_mpll = { - .name = "mpll", - .id = -1, -}; - -struct clk clk_upll = { - .name = "upll", - .id = -1, - .parent = NULL, - .ctrlbit = 0, -}; - -struct clk clk_f = { - .name = "fclk", - .id = -1, - .rate = 0, - .parent = &clk_mpll, - .ctrlbit = 0, -}; - -struct clk clk_h = { - .name = "hclk", - .id = -1, - .rate = 0, - .parent = NULL, - .ctrlbit = 0, -}; - -struct clk clk_p = { - .name = "pclk", - .id = -1, - .rate = 0, - .parent = NULL, - .ctrlbit = 0, -}; - -struct clk clk_usb_bus = { - .name = "usb-bus", - .id = -1, - .rate = 0, - .parent = &clk_upll, -}; - -/* clocks that could be registered by external code */ - -static int s3c24xx_dclk_enable(struct clk *clk, int enable) -{ - unsigned long dclkcon = __raw_readl(S3C24XX_DCLKCON); + unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW); + unsigned long orig = clkslow; if (enable) - dclkcon |= clk->ctrlbit; + clkslow &= ~S3C2410_CLKSLOW_UCLK_OFF; else - dclkcon &= ~clk->ctrlbit; + clkslow |= S3C2410_CLKSLOW_UCLK_OFF; - __raw_writel(dclkcon, S3C24XX_DCLKCON); + __raw_writel(clkslow, S3C2410_CLKSLOW); - return 0; -} + /* if we started the UPLL, then allow to settle */ -static int s3c24xx_dclk_setparent(struct clk *clk, struct clk *parent) -{ - unsigned long dclkcon; - unsigned int uclk; - - if (parent == &clk_upll) - uclk = 1; - else if (parent == &clk_p) - uclk = 0; - else - return -EINVAL; - - clk->parent = parent; - - dclkcon = __raw_readl(S3C24XX_DCLKCON); - - if (clk->ctrlbit == S3C2410_DCLKCON_DCLK0EN) { - if (uclk) - dclkcon |= S3C2410_DCLKCON_DCLK0_UCLK; - else - dclkcon &= ~S3C2410_DCLKCON_DCLK0_UCLK; - } else { - if (uclk) - dclkcon |= S3C2410_DCLKCON_DCLK1_UCLK; - else - dclkcon &= ~S3C2410_DCLKCON_DCLK1_UCLK; - } - - __raw_writel(dclkcon, S3C24XX_DCLKCON); + if (enable && (orig & S3C2410_CLKSLOW_UCLK_OFF)) + udelay(200); return 0; } - -static int s3c24xx_clkout_setparent(struct clk *clk, struct clk *parent) -{ - unsigned long mask; - unsigned long source; - - /* calculate the MISCCR setting for the clock */ - - if (parent == &clk_xtal) - source = S3C2410_MISCCR_CLK0_MPLL; - else if (parent == &clk_upll) - source = S3C2410_MISCCR_CLK0_UPLL; - else if (parent == &clk_f) - source = S3C2410_MISCCR_CLK0_FCLK; - else if (parent == &clk_h) - source = S3C2410_MISCCR_CLK0_HCLK; - else if (parent == &clk_p) - source = S3C2410_MISCCR_CLK0_PCLK; - else if (clk == &s3c24xx_clkout0 && parent == &s3c24xx_dclk0) - source = S3C2410_MISCCR_CLK0_DCLK0; - else if (clk == &s3c24xx_clkout1 && parent == &s3c24xx_dclk1) - source = S3C2410_MISCCR_CLK0_DCLK0; - else - return -EINVAL; - - clk->parent = parent; - - if (clk == &s3c24xx_dclk0) - mask = S3C2410_MISCCR_CLK0_MASK; - else { - source <<= 4; - mask = S3C2410_MISCCR_CLK1_MASK; +/* standard clock definitions */ + +static struct clk init_clocks_disable[] = { + { + .name = "nand", + .id = -1, + .parent = &clk_h, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_NAND, + }, { + .name = "sdi", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_SDI, + }, { + .name = "adc", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_ADC, + }, { + .name = "i2c", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_IIC, + }, { + .name = "iis", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_IIS, + }, { + .name = "spi", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_SPI, } - - s3c2410_modify_misccr(mask, source); - return 0; -} - -/* external clock definitions */ - -struct clk s3c24xx_dclk0 = { - .name = "dclk0", - .id = -1, - .ctrlbit = S3C2410_DCLKCON_DCLK0EN, - .enable = s3c24xx_dclk_enable, - .set_parent = s3c24xx_dclk_setparent, -}; - -struct clk s3c24xx_dclk1 = { - .name = "dclk1", - .id = -1, - .ctrlbit = S3C2410_DCLKCON_DCLK0EN, - .enable = s3c24xx_dclk_enable, - .set_parent = s3c24xx_dclk_setparent, }; -struct clk s3c24xx_clkout0 = { - .name = "clkout0", - .id = -1, - .set_parent = s3c24xx_clkout_setparent, +static struct clk init_clocks[] = { + { + .name = "lcd", + .id = -1, + .parent = &clk_h, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_LCDC, + }, { + .name = "gpio", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_GPIO, + }, { + .name = "usb-host", + .id = -1, + .parent = &clk_h, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_USBH, + }, { + .name = "usb-device", + .id = -1, + .parent = &clk_h, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_USBD, + }, { + .name = "timers", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_PWMT, + }, { + .name = "uart", + .id = 0, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_UART0, + }, { + .name = "uart", + .id = 1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_UART1, + }, { + .name = "uart", + .id = 2, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_UART2, + }, { + .name = "rtc", + .id = -1, + .parent = &clk_p, + .enable = s3c2410_clkcon_enable, + .ctrlbit = S3C2410_CLKCON_RTC, + }, { + .name = "watchdog", + .id = -1, + .parent = &clk_p, + .ctrlbit = 0, + }, { + .name = "usb-bus-host", + .id = -1, + .parent = &clk_usb_bus, + }, { + .name = "usb-bus-gadget", + .id = -1, + .parent = &clk_usb_bus, + }, }; -struct clk s3c24xx_clkout1 = { - .name = "clkout1", - .id = -1, - .set_parent = s3c24xx_clkout_setparent, -}; - -struct clk s3c24xx_uclk = { - .name = "uclk", - .id = -1, -}; - -/* initialise the clock system */ - -int s3c24xx_register_clock(struct clk *clk) -{ - clk->owner = THIS_MODULE; - - if (clk->enable == NULL) - clk->enable = clk_null_enable; - - /* add to the list of available clocks */ - - mutex_lock(&clocks_mutex); - list_add(&clk->list, &clocks); - mutex_unlock(&clocks_mutex); - - return 0; -} - -/* initalise all the clocks */ +/* s3c2410_baseclk_add() + * + * Add all the clocks used by the s3c2410 or compatible CPUs + * such as the S3C2440 and S3C2442. + * + * We cannot use a system device as we are needed before any + * of the init-calls that initialise the devices are actually + * done. +*/ -int __init s3c24xx_setup_clocks(unsigned long xtal, - unsigned long fclk, - unsigned long hclk, - unsigned long pclk) +int __init s3c2410_baseclk_add(void) { - printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n"); + unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW); + unsigned long clkcon = __raw_readl(S3C2410_CLKCON); + struct clk *clkp; + struct clk *xtal; + int ret; + int ptr; - /* initialise the main system clocks */ + clk_upll.enable = s3c2410_upll_enable; - clk_xtal.rate = xtal; - clk_upll.rate = s3c2410_get_pll(__raw_readl(S3C2410_UPLLCON), xtal); + if (s3c24xx_register_clock(&clk_usb_bus) < 0) + printk(KERN_ERR "failed to register usb bus clock\n"); - clk_mpll.rate = fclk; - clk_h.rate = hclk; - clk_p.rate = pclk; - clk_f.rate = fclk; + /* register clocks from clock array */ - /* assume uart clocks are correctly setup */ + clkp = init_clocks; + for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) { + /* ensure that we note the clock state */ - /* register our clocks */ + clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0; - if (s3c24xx_register_clock(&clk_xtal) < 0) - printk(KERN_ERR "failed to register master xtal\n"); + ret = s3c24xx_register_clock(clkp); + if (ret < 0) { + printk(KERN_ERR "Failed to register clock %s (%d)\n", + clkp->name, ret); + } + } - if (s3c24xx_register_clock(&clk_mpll) < 0) - printk(KERN_ERR "failed to register mpll clock\n"); + /* We must be careful disabling the clocks we are not intending to + * be using at boot time, as subsytems such as the LCD which do + * their own DMA requests to the bus can cause the system to lockup + * if they where in the middle of requesting bus access. + * + * Disabling the LCD clock if the LCD is active is very dangerous, + * and therefore the bootloader should be careful to not enable + * the LCD clock if it is not needed. + */ + + /* install (and disable) the clocks we do not need immediately */ + + clkp = init_clocks_disable; + for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) { + + ret = s3c24xx_register_clock(clkp); + if (ret < 0) { + printk(KERN_ERR "Failed to register clock %s (%d)\n", + clkp->name, ret); + } - if (s3c24xx_register_clock(&clk_upll) < 0) - printk(KERN_ERR "failed to register upll clock\n"); + s3c2410_clkcon_enable(clkp, 0); + } - if (s3c24xx_register_clock(&clk_f) < 0) - printk(KERN_ERR "failed to register cpu fclk\n"); + /* show the clock-slow value */ - if (s3c24xx_register_clock(&clk_h) < 0) - printk(KERN_ERR "failed to register cpu hclk\n"); + xtal = clk_get(NULL, "xtal"); - if (s3c24xx_register_clock(&clk_p) < 0) - printk(KERN_ERR "failed to register cpu pclk\n"); + printk("CLOCK: Slow mode (%ld.%ld MHz), %s, MPLL %s, UPLL %s\n", + print_mhz(clk_get_rate(xtal) / + ( 2 * S3C2410_CLKSLOW_GET_SLOWVAL(clkslow))), + (clkslow & S3C2410_CLKSLOW_SLOW) ? "slow" : "fast", + (clkslow & S3C2410_CLKSLOW_MPLL_OFF) ? "off" : "on", + (clkslow & S3C2410_CLKSLOW_UCLK_OFF) ? "off" : "on"); return 0; } |