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authorAndrew Victor <andrew@sanpeople.com>2007-02-05 11:42:07 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2007-02-08 14:50:56 +0000
commit9d0412680e6c7b685ee466842047bcfb924d6dc5 (patch)
treec79300964ef1aca5d24571696f95e76b37c14679 /arch/arm/mach-at91rm9200/clock.c
parenta93d48cc6019f84394b31d10c0d830a3b71696be (diff)
downloadlinux-2.6.34-ux500-9d0412680e6c7b685ee466842047bcfb924d6dc5.tar.gz
[ARM] 4124/1: Rename mach-at91rm9200 and arch-at91rm9200 directories
Now that Linux includes support for the Atmel AT91SAM9260 and AT91SAM9261 processors in addition to the original Atmel AT91RM9200 (with support for more AT91 processors pending), the "mach-at91rm9200" and "arch-at91rm9200" directories should be renamed to indicate their more generic nature. The following git commands should be run BEFORE applying this patch: git-mv arch/arm/mach-at91rm9200 arch/arm/mach-at91 git-mv include/asm-arm/arch-at91rm9200 include/asm-arm/arch-at91 Signed-off-by: Andrew Victor <andrew@sanpeople.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-at91rm9200/clock.c')
-rw-r--r--arch/arm/mach-at91rm9200/clock.c644
1 files changed, 0 insertions, 644 deletions
diff --git a/arch/arm/mach-at91rm9200/clock.c b/arch/arm/mach-at91rm9200/clock.c
deleted file mode 100644
index 4dee21fefe5..00000000000
--- a/arch/arm/mach-at91rm9200/clock.c
+++ /dev/null
@@ -1,644 +0,0 @@
-/*
- * linux/arch/arm/mach-at91rm9200/clock.c
- *
- * Copyright (C) 2005 David Brownell
- * Copyright (C) 2005 Ivan Kokshaysky
- *
- * 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/module.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/fs.h>
-#include <linux/debugfs.h>
-#include <linux/seq_file.h>
-#include <linux/list.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-#include <linux/spinlock.h>
-#include <linux/delay.h>
-#include <linux/clk.h>
-
-#include <asm/semaphore.h>
-#include <asm/io.h>
-#include <asm/mach-types.h>
-
-#include <asm/hardware.h>
-#include <asm/arch/at91_pmc.h>
-#include <asm/arch/cpu.h>
-
-#include "clock.h"
-
-
-/*
- * There's a lot more which can be done with clocks, including cpufreq
- * integration, slow clock mode support (for system suspend), letting
- * PLLB be used at other rates (on boards that don't need USB), etc.
- */
-
-#define clk_is_primary(x) ((x)->type & CLK_TYPE_PRIMARY)
-#define clk_is_programmable(x) ((x)->type & CLK_TYPE_PROGRAMMABLE)
-#define clk_is_peripheral(x) ((x)->type & CLK_TYPE_PERIPHERAL)
-#define clk_is_sys(x) ((x)->type & CLK_TYPE_SYSTEM)
-
-
-static LIST_HEAD(clocks);
-static DEFINE_SPINLOCK(clk_lock);
-
-static u32 at91_pllb_usb_init;
-
-/*
- * Four primary clock sources: two crystal oscillators (32K, main), and
- * two PLLs. PLLA usually runs the master clock; and PLLB must run at
- * 48 MHz (unless no USB function clocks are needed). The main clock and
- * both PLLs are turned off to run in "slow clock mode" (system suspend).
- */
-static struct clk clk32k = {
- .name = "clk32k",
- .rate_hz = AT91_SLOW_CLOCK,
- .users = 1, /* always on */
- .id = 0,
- .type = CLK_TYPE_PRIMARY,
-};
-static struct clk main_clk = {
- .name = "main",
- .pmc_mask = AT91_PMC_MOSCS, /* in PMC_SR */
- .id = 1,
- .type = CLK_TYPE_PRIMARY,
-};
-static struct clk plla = {
- .name = "plla",
- .parent = &main_clk,
- .pmc_mask = AT91_PMC_LOCKA, /* in PMC_SR */
- .id = 2,
- .type = CLK_TYPE_PRIMARY | CLK_TYPE_PLL,
-};
-
-static void pllb_mode(struct clk *clk, int is_on)
-{
- u32 value;
-
- if (is_on) {
- is_on = AT91_PMC_LOCKB;
- value = at91_pllb_usb_init;
- } else
- value = 0;
-
- // REVISIT: Add work-around for AT91RM9200 Errata #26 ?
- at91_sys_write(AT91_CKGR_PLLBR, value);
-
- do {
- cpu_relax();
- } while ((at91_sys_read(AT91_PMC_SR) & AT91_PMC_LOCKB) != is_on);
-}
-
-static struct clk pllb = {
- .name = "pllb",
- .parent = &main_clk,
- .pmc_mask = AT91_PMC_LOCKB, /* in PMC_SR */
- .mode = pllb_mode,
- .id = 3,
- .type = CLK_TYPE_PRIMARY | CLK_TYPE_PLL,
-};
-
-static void pmc_sys_mode(struct clk *clk, int is_on)
-{
- if (is_on)
- at91_sys_write(AT91_PMC_SCER, clk->pmc_mask);
- else
- at91_sys_write(AT91_PMC_SCDR, clk->pmc_mask);
-}
-
-/* USB function clocks (PLLB must be 48 MHz) */
-static struct clk udpck = {
- .name = "udpck",
- .parent = &pllb,
- .mode = pmc_sys_mode,
-};
-static struct clk uhpck = {
- .name = "uhpck",
- .parent = &pllb,
- .mode = pmc_sys_mode,
-};
-
-
-/*
- * The master clock is divided from the CPU clock (by 1-4). It's used for
- * memory, interfaces to on-chip peripherals, the AIC, and sometimes more
- * (e.g baud rate generation). It's sourced from one of the primary clocks.
- */
-static struct clk mck = {
- .name = "mck",
- .pmc_mask = AT91_PMC_MCKRDY, /* in PMC_SR */
-};
-
-static void pmc_periph_mode(struct clk *clk, int is_on)
-{
- if (is_on)
- at91_sys_write(AT91_PMC_PCER, clk->pmc_mask);
- else
- at91_sys_write(AT91_PMC_PCDR, clk->pmc_mask);
-}
-
-static struct clk __init *at91_css_to_clk(unsigned long css)
-{
- switch (css) {
- case AT91_PMC_CSS_SLOW:
- return &clk32k;
- case AT91_PMC_CSS_MAIN:
- return &main_clk;
- case AT91_PMC_CSS_PLLA:
- return &plla;
- case AT91_PMC_CSS_PLLB:
- return &pllb;
- }
-
- return NULL;
-}
-
-/*
- * Associate a particular clock with a function (eg, "uart") and device.
- * The drivers can then request the same 'function' with several different
- * devices and not care about which clock name to use.
- */
-void __init at91_clock_associate(const char *id, struct device *dev, const char *func)
-{
- struct clk *clk = clk_get(NULL, id);
-
- if (!dev || !clk || !IS_ERR(clk_get(dev, func)))
- return;
-
- clk->function = func;
- clk->dev = dev;
-}
-
-/* clocks cannot be de-registered no refcounting necessary */
-struct clk *clk_get(struct device *dev, const char *id)
-{
- struct clk *clk;
-
- list_for_each_entry(clk, &clocks, node) {
- if (strcmp(id, clk->name) == 0)
- return clk;
- if (clk->function && (dev == clk->dev) && strcmp(id, clk->function) == 0)
- return clk;
- }
-
- return ERR_PTR(-ENOENT);
-}
-EXPORT_SYMBOL(clk_get);
-
-void clk_put(struct clk *clk)
-{
-}
-EXPORT_SYMBOL(clk_put);
-
-static void __clk_enable(struct clk *clk)
-{
- if (clk->parent)
- __clk_enable(clk->parent);
- if (clk->users++ == 0 && clk->mode)
- clk->mode(clk, 1);
-}
-
-int clk_enable(struct clk *clk)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&clk_lock, flags);
- __clk_enable(clk);
- spin_unlock_irqrestore(&clk_lock, flags);
- return 0;
-}
-EXPORT_SYMBOL(clk_enable);
-
-static void __clk_disable(struct clk *clk)
-{
- BUG_ON(clk->users == 0);
- if (--clk->users == 0 && clk->mode)
- clk->mode(clk, 0);
- if (clk->parent)
- __clk_disable(clk->parent);
-}
-
-void clk_disable(struct clk *clk)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&clk_lock, flags);
- __clk_disable(clk);
- spin_unlock_irqrestore(&clk_lock, flags);
-}
-EXPORT_SYMBOL(clk_disable);
-
-unsigned long clk_get_rate(struct clk *clk)
-{
- unsigned long flags;
- unsigned long rate;
-
- spin_lock_irqsave(&clk_lock, flags);
- for (;;) {
- rate = clk->rate_hz;
- if (rate || !clk->parent)
- break;
- clk = clk->parent;
- }
- spin_unlock_irqrestore(&clk_lock, flags);
- return rate;
-}
-EXPORT_SYMBOL(clk_get_rate);
-
-/*------------------------------------------------------------------------*/
-
-#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS
-
-/*
- * For now, only the programmable clocks support reparenting (MCK could
- * do this too, with care) or rate changing (the PLLs could do this too,
- * ditto MCK but that's more for cpufreq). Drivers may reparent to get
- * a better rate match; we don't.
- */
-
-long clk_round_rate(struct clk *clk, unsigned long rate)
-{
- unsigned long flags;
- unsigned prescale;
- unsigned long actual;
-
- if (!clk_is_programmable(clk))
- return -EINVAL;
- spin_lock_irqsave(&clk_lock, flags);
-
- actual = clk->parent->rate_hz;
- for (prescale = 0; prescale < 7; prescale++) {
- if (actual && actual <= rate)
- break;
- actual >>= 1;
- }
-
- spin_unlock_irqrestore(&clk_lock, flags);
- return (prescale < 7) ? actual : -ENOENT;
-}
-EXPORT_SYMBOL(clk_round_rate);
-
-int clk_set_rate(struct clk *clk, unsigned long rate)
-{
- unsigned long flags;
- unsigned prescale;
- unsigned long actual;
-
- if (!clk_is_programmable(clk))
- return -EINVAL;
- if (clk->users)
- return -EBUSY;
- spin_lock_irqsave(&clk_lock, flags);
-
- actual = clk->parent->rate_hz;
- for (prescale = 0; prescale < 7; prescale++) {
- if (actual && actual <= rate) {
- u32 pckr;
-
- pckr = at91_sys_read(AT91_PMC_PCKR(clk->id));
- pckr &= AT91_PMC_CSS_PLLB; /* clock selection */
- pckr |= prescale << 2;
- at91_sys_write(AT91_PMC_PCKR(clk->id), pckr);
- clk->rate_hz = actual;
- break;
- }
- actual >>= 1;
- }
-
- spin_unlock_irqrestore(&clk_lock, flags);
- return (prescale < 7) ? actual : -ENOENT;
-}
-EXPORT_SYMBOL(clk_set_rate);
-
-struct clk *clk_get_parent(struct clk *clk)
-{
- return clk->parent;
-}
-EXPORT_SYMBOL(clk_get_parent);
-
-int clk_set_parent(struct clk *clk, struct clk *parent)
-{
- unsigned long flags;
-
- if (clk->users)
- return -EBUSY;
- if (!clk_is_primary(parent) || !clk_is_programmable(clk))
- return -EINVAL;
- spin_lock_irqsave(&clk_lock, flags);
-
- clk->rate_hz = parent->rate_hz;
- clk->parent = parent;
- at91_sys_write(AT91_PMC_PCKR(clk->id), parent->id);
-
- spin_unlock_irqrestore(&clk_lock, flags);
- return 0;
-}
-EXPORT_SYMBOL(clk_set_parent);
-
-/* establish PCK0..PCK3 parentage and rate */
-static void init_programmable_clock(struct clk *clk)
-{
- struct clk *parent;
- u32 pckr;
-
- pckr = at91_sys_read(AT91_PMC_PCKR(clk->id));
- parent = at91_css_to_clk(pckr & AT91_PMC_CSS);
- clk->parent = parent;
- clk->rate_hz = parent->rate_hz / (1 << ((pckr >> 2) & 3));
-}
-
-#endif /* CONFIG_AT91_PROGRAMMABLE_CLOCKS */
-
-/*------------------------------------------------------------------------*/
-
-#ifdef CONFIG_DEBUG_FS
-
-static int at91_clk_show(struct seq_file *s, void *unused)
-{
- u32 scsr, pcsr, sr;
- struct clk *clk;
- unsigned i;
-
- seq_printf(s, "SCSR = %8x\n", scsr = at91_sys_read(AT91_PMC_SCSR));
- seq_printf(s, "PCSR = %8x\n", pcsr = at91_sys_read(AT91_PMC_PCSR));
-
- seq_printf(s, "MOR = %8x\n", at91_sys_read(AT91_CKGR_MOR));
- seq_printf(s, "MCFR = %8x\n", at91_sys_read(AT91_CKGR_MCFR));
- seq_printf(s, "PLLA = %8x\n", at91_sys_read(AT91_CKGR_PLLAR));
- seq_printf(s, "PLLB = %8x\n", at91_sys_read(AT91_CKGR_PLLBR));
-
- seq_printf(s, "MCKR = %8x\n", at91_sys_read(AT91_PMC_MCKR));
- for (i = 0; i < 4; i++)
- seq_printf(s, "PCK%d = %8x\n", i, at91_sys_read(AT91_PMC_PCKR(i)));
- seq_printf(s, "SR = %8x\n", sr = at91_sys_read(AT91_PMC_SR));
-
- seq_printf(s, "\n");
-
- list_for_each_entry(clk, &clocks, node) {
- char *state;
-
- if (clk->mode == pmc_sys_mode)
- state = (scsr & clk->pmc_mask) ? "on" : "off";
- else if (clk->mode == pmc_periph_mode)
- state = (pcsr & clk->pmc_mask) ? "on" : "off";
- else if (clk->pmc_mask)
- state = (sr & clk->pmc_mask) ? "on" : "off";
- else if (clk == &clk32k || clk == &main_clk)
- state = "on";
- else
- state = "";
-
- seq_printf(s, "%-10s users=%2d %-3s %9ld Hz %s\n",
- clk->name, clk->users, state, clk_get_rate(clk),
- clk->parent ? clk->parent->name : "");
- }
- return 0;
-}
-
-static int at91_clk_open(struct inode *inode, struct file *file)
-{
- return single_open(file, at91_clk_show, NULL);
-}
-
-static struct file_operations at91_clk_operations = {
- .open = at91_clk_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
-static int __init at91_clk_debugfs_init(void)
-{
- /* /sys/kernel/debug/at91_clk */
- (void) debugfs_create_file("at91_clk", S_IFREG | S_IRUGO, NULL, NULL, &at91_clk_operations);
-
- return 0;
-}
-postcore_initcall(at91_clk_debugfs_init);
-
-#endif
-
-/*------------------------------------------------------------------------*/
-
-/* Register a new clock */
-int __init clk_register(struct clk *clk)
-{
- if (clk_is_peripheral(clk)) {
- clk->parent = &mck;
- clk->mode = pmc_periph_mode;
- list_add_tail(&clk->node, &clocks);
- }
- else if (clk_is_sys(clk)) {
- clk->parent = &mck;
- clk->mode = pmc_sys_mode;
-
- list_add_tail(&clk->node, &clocks);
- }
-#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS
- else if (clk_is_programmable(clk)) {
- clk->mode = pmc_sys_mode;
- init_programmable_clock(clk);
- list_add_tail(&clk->node, &clocks);
- }
-#endif
-
- return 0;
-}
-
-
-/*------------------------------------------------------------------------*/
-
-static u32 __init at91_pll_rate(struct clk *pll, u32 freq, u32 reg)
-{
- unsigned mul, div;
-
- div = reg & 0xff;
- mul = (reg >> 16) & 0x7ff;
- if (div && mul) {
- freq /= div;
- freq *= mul + 1;
- } else
- freq = 0;
-
- return freq;
-}
-
-static u32 __init at91_usb_rate(struct clk *pll, u32 freq, u32 reg)
-{
- if (pll == &pllb && (reg & AT91_PMC_USB96M))
- return freq / 2;
- else
- return freq;
-}
-
-static unsigned __init at91_pll_calc(unsigned main_freq, unsigned out_freq)
-{
- unsigned i, div = 0, mul = 0, diff = 1 << 30;
- unsigned ret = (out_freq > 155000000) ? 0xbe00 : 0x3e00;
-
- /* PLL output max 240 MHz (or 180 MHz per errata) */
- if (out_freq > 240000000)
- goto fail;
-
- for (i = 1; i < 256; i++) {
- int diff1;
- unsigned input, mul1;
-
- /*
- * PLL input between 1MHz and 32MHz per spec, but lower
- * frequences seem necessary in some cases so allow 100K.
- */
- input = main_freq / i;
- if (input < 100000)
- continue;
- if (input > 32000000)
- continue;
-
- mul1 = out_freq / input;
- if (mul1 > 2048)
- continue;
- if (mul1 < 2)
- goto fail;
-
- diff1 = out_freq - input * mul1;
- if (diff1 < 0)
- diff1 = -diff1;
- if (diff > diff1) {
- diff = diff1;
- div = i;
- mul = mul1;
- if (diff == 0)
- break;
- }
- }
- if (i == 256 && diff > (out_freq >> 5))
- goto fail;
- return ret | ((mul - 1) << 16) | div;
-fail:
- return 0;
-}
-
-/*
- * Several unused clocks may be active. Turn them off.
- */
-static void __init at91_periphclk_reset(void)
-{
- unsigned long reg;
- struct clk *clk;
-
- reg = at91_sys_read(AT91_PMC_PCSR);
-
- list_for_each_entry(clk, &clocks, node) {
- if (clk->mode != pmc_periph_mode)
- continue;
-
- if (clk->users > 0)
- reg &= ~clk->pmc_mask;
- }
-
- at91_sys_write(AT91_PMC_PCDR, reg);
-}
-
-static struct clk *const standard_pmc_clocks[] __initdata = {
- /* four primary clocks */
- &clk32k,
- &main_clk,
- &plla,
- &pllb,
-
- /* PLLB children (USB) */
- &udpck,
- &uhpck,
-
- /* MCK */
- &mck
-};
-
-int __init at91_clock_init(unsigned long main_clock)
-{
- unsigned tmp, freq, mckr;
- int i;
-
- /*
- * When the bootloader initialized the main oscillator correctly,
- * there's no problem using the cycle counter. But if it didn't,
- * or when using oscillator bypass mode, we must be told the speed
- * of the main clock.
- */
- if (!main_clock) {
- do {
- tmp = at91_sys_read(AT91_CKGR_MCFR);
- } while (!(tmp & AT91_PMC_MAINRDY));
- main_clock = (tmp & AT91_PMC_MAINF) * (AT91_SLOW_CLOCK / 16);
- }
- main_clk.rate_hz = main_clock;
-
- /* report if PLLA is more than mildly overclocked */
- plla.rate_hz = at91_pll_rate(&plla, main_clock, at91_sys_read(AT91_CKGR_PLLAR));
- if (plla.rate_hz > 209000000)
- pr_info("Clocks: PLLA overclocked, %ld MHz\n", plla.rate_hz / 1000000);
-
- /*
- * USB clock init: choose 48 MHz PLLB value, turn all clocks off,
- * disable 48MHz clock during usb peripheral suspend.
- *
- * REVISIT: assumes MCK doesn't derive from PLLB!
- */
- at91_pllb_usb_init = at91_pll_calc(main_clock, 48000000 * 2) | AT91_PMC_USB96M;
- pllb.rate_hz = at91_pll_rate(&pllb, main_clock, at91_pllb_usb_init);
- if (cpu_is_at91rm9200()) {
- uhpck.pmc_mask = AT91RM9200_PMC_UHP;
- udpck.pmc_mask = AT91RM9200_PMC_UDP;
- at91_sys_write(AT91_PMC_SCDR, AT91RM9200_PMC_UHP | AT91RM9200_PMC_UDP);
- at91_sys_write(AT91_PMC_SCER, AT91RM9200_PMC_MCKUDP);
- } else if (cpu_is_at91sam9260()) {
- uhpck.pmc_mask = AT91SAM926x_PMC_UHP;
- udpck.pmc_mask = AT91SAM926x_PMC_UDP;
- at91_sys_write(AT91_PMC_SCDR, AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP);
- } else if (cpu_is_at91sam9261()) {
- uhpck.pmc_mask = (AT91SAM926x_PMC_UHP | AT91_PMC_HCK0);
- udpck.pmc_mask = AT91SAM926x_PMC_UDP;
- at91_sys_write(AT91_PMC_SCDR, AT91SAM926x_PMC_UHP | AT91_PMC_HCK0 | AT91SAM926x_PMC_UDP);
- }
- at91_sys_write(AT91_CKGR_PLLBR, 0);
-
- udpck.rate_hz = at91_usb_rate(&pllb, pllb.rate_hz, at91_pllb_usb_init);
- uhpck.rate_hz = at91_usb_rate(&pllb, pllb.rate_hz, at91_pllb_usb_init);
-
- /*
- * MCK and CPU derive from one of those primary clocks.
- * For now, assume this parentage won't change.
- */
- mckr = at91_sys_read(AT91_PMC_MCKR);
- mck.parent = at91_css_to_clk(mckr & AT91_PMC_CSS);
- freq = mck.parent->rate_hz;
- freq /= (1 << ((mckr >> 2) & 3)); /* prescale */
- mck.rate_hz = freq / (1 + ((mckr >> 8) & 3)); /* mdiv */
-
- /* Register the PMC's standard clocks */
- for (i = 0; i < ARRAY_SIZE(standard_pmc_clocks); i++)
- list_add_tail(&standard_pmc_clocks[i]->node, &clocks);
-
- /* MCK and CPU clock are "always on" */
- clk_enable(&mck);
-
- printk("Clocks: CPU %u MHz, master %u MHz, main %u.%03u MHz\n",
- freq / 1000000, (unsigned) mck.rate_hz / 1000000,
- (unsigned) main_clock / 1000000,
- ((unsigned) main_clock % 1000000) / 1000);
-
- /* disable all programmable clocks */
- at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK0 | AT91_PMC_PCK1 | AT91_PMC_PCK2 | AT91_PMC_PCK3);
-
- /* disable all other unused peripheral clocks */
- at91_periphclk_reset();
-
- return 0;
-}