aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/mach-davinci/clock.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-davinci/clock.c')
-rw-r--r--arch/arm/mach-davinci/clock.c495
1 files changed, 404 insertions, 91 deletions
diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c
index 83d54d50b5e..985e5fd00fb 100644
--- a/arch/arm/mach-davinci/clock.c
+++ b/arch/arm/mach-davinci/clock.c
@@ -17,11 +17,12 @@
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/mutex.h>
-#include <linux/platform_device.h>
#include <linux/io.h>
+#include <linux/delay.h>
#include <mach/hardware.h>
+#include <mach/clock.h>
#include <mach/psc.h>
#include <mach/cputype.h>
#include "clock.h"
@@ -30,33 +31,68 @@ static LIST_HEAD(clocks);
static DEFINE_MUTEX(clocks_mutex);
static DEFINE_SPINLOCK(clockfw_lock);
-static unsigned psc_domain(struct clk *clk)
-{
- return (clk->flags & PSC_DSP)
- ? DAVINCI_GPSC_DSPDOMAIN
- : DAVINCI_GPSC_ARMDOMAIN;
-}
-
static void __clk_enable(struct clk *clk)
{
if (clk->parent)
__clk_enable(clk->parent);
- if (clk->usecount++ == 0 && (clk->flags & CLK_PSC))
- davinci_psc_config(psc_domain(clk), clk->psc_ctlr,
- clk->lpsc, 1);
+ if (clk->usecount++ == 0) {
+ if (clk->flags & CLK_PSC)
+ davinci_psc_config(clk->domain, clk->gpsc, clk->lpsc,
+ true, clk->flags);
+ else if (clk->clk_enable)
+ clk->clk_enable(clk);
+ }
}
static void __clk_disable(struct clk *clk)
{
if (WARN_ON(clk->usecount == 0))
return;
- if (--clk->usecount == 0 && !(clk->flags & CLK_PLL))
- davinci_psc_config(psc_domain(clk), clk->psc_ctlr,
- clk->lpsc, 0);
+ if (--clk->usecount == 0) {
+ if (!(clk->flags & CLK_PLL) && (clk->flags & CLK_PSC))
+ davinci_psc_config(clk->domain, clk->gpsc, clk->lpsc,
+ false, clk->flags);
+ else if (clk->clk_disable)
+ clk->clk_disable(clk);
+ }
if (clk->parent)
__clk_disable(clk->parent);
}
+int davinci_clk_reset(struct clk *clk, bool reset)
+{
+ unsigned long flags;
+
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ if (clk->flags & CLK_PSC)
+ davinci_psc_reset(clk->gpsc, clk->lpsc, reset);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(davinci_clk_reset);
+
+int davinci_clk_reset_assert(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk) || !clk->reset)
+ return -EINVAL;
+
+ return clk->reset(clk, true);
+}
+EXPORT_SYMBOL(davinci_clk_reset_assert);
+
+int davinci_clk_reset_deassert(struct clk *clk)
+{
+ if (clk == NULL || IS_ERR(clk) || !clk->reset)
+ return -EINVAL;
+
+ return clk->reset(clk, false);
+}
+EXPORT_SYMBOL(davinci_clk_reset_deassert);
+
int clk_enable(struct clk *clk)
{
unsigned long flags;
@@ -97,22 +133,77 @@ EXPORT_SYMBOL(clk_get_rate);
long clk_round_rate(struct clk *clk, unsigned long rate)
{
if (clk == NULL || IS_ERR(clk))
- return -EINVAL;
+ return 0;
+
+ if (clk->round_rate)
+ return clk->round_rate(clk, rate);
return clk->rate;
}
EXPORT_SYMBOL(clk_round_rate);
+/* Propagate rate to children */
+static void propagate_rate(struct clk *root)
+{
+ struct clk *clk;
+
+ list_for_each_entry(clk, &root->children, childnode) {
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+ propagate_rate(clk);
+ }
+}
+
int clk_set_rate(struct clk *clk, unsigned long rate)
{
+ unsigned long flags;
+ int ret = -EINVAL;
+
if (clk == NULL || IS_ERR(clk))
- return -EINVAL;
+ return ret;
+
+ if (clk->set_rate)
+ ret = clk->set_rate(clk, rate);
- /* changing the clk rate is not supported */
- return -EINVAL;
+ spin_lock_irqsave(&clockfw_lock, flags);
+ if (ret == 0) {
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+ propagate_rate(clk);
+ }
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return ret;
}
EXPORT_SYMBOL(clk_set_rate);
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+ unsigned long flags;
+
+ if (clk == NULL || IS_ERR(clk))
+ return -EINVAL;
+
+ /* Cannot change parent on enabled clock */
+ if (WARN_ON(clk->usecount))
+ return -EINVAL;
+
+ mutex_lock(&clocks_mutex);
+ clk->parent = parent;
+ list_del_init(&clk->childnode);
+ list_add(&clk->childnode, &clk->parent->children);
+ mutex_unlock(&clocks_mutex);
+
+ spin_lock_irqsave(&clockfw_lock, flags);
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+ propagate_rate(clk);
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
int clk_register(struct clk *clk)
{
if (clk == NULL || IS_ERR(clk))
@@ -123,16 +214,24 @@ int clk_register(struct clk *clk)
clk->name, clk->parent->name))
return -EINVAL;
+ INIT_LIST_HEAD(&clk->children);
+
mutex_lock(&clocks_mutex);
list_add_tail(&clk->node, &clocks);
+ if (clk->parent)
+ list_add_tail(&clk->childnode, &clk->parent->children);
mutex_unlock(&clocks_mutex);
/* If rate is already set, use it */
if (clk->rate)
return 0;
+ /* Else, see if there is a way to calculate it */
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
+
/* Otherwise, default to parent rate */
- if (clk->parent)
+ else if (clk->parent)
clk->rate = clk->parent->rate;
return 0;
@@ -146,6 +245,7 @@ void clk_unregister(struct clk *clk)
mutex_lock(&clocks_mutex);
list_del(&clk->node);
+ list_del(&clk->childnode);
mutex_unlock(&clocks_mutex);
}
EXPORT_SYMBOL(clk_unregister);
@@ -154,7 +254,7 @@ EXPORT_SYMBOL(clk_unregister);
/*
* Disable any unused clocks left on by the bootloader
*/
-static int __init clk_disable_unused(void)
+int __init davinci_clk_disable_unused(void)
{
struct clk *ck;
@@ -166,63 +266,154 @@ static int __init clk_disable_unused(void)
continue;
/* ignore if in Disabled or SwRstDisable states */
- if (!davinci_psc_is_clk_active(ck->psc_ctlr, ck->lpsc))
+ if (!davinci_psc_is_clk_active(ck->gpsc, ck->lpsc))
continue;
- pr_info("Clocks: disable unused %s\n", ck->name);
- davinci_psc_config(psc_domain(ck), ck->psc_ctlr, ck->lpsc, 0);
+ pr_debug("Clocks: disable unused %s\n", ck->name);
+
+ davinci_psc_config(ck->domain, ck->gpsc, ck->lpsc,
+ false, ck->flags);
}
spin_unlock_irq(&clockfw_lock);
return 0;
}
-late_initcall(clk_disable_unused);
#endif
-static void clk_sysclk_recalc(struct clk *clk)
+static unsigned long clk_sysclk_recalc(struct clk *clk)
{
u32 v, plldiv;
struct pll_data *pll;
+ unsigned long rate = clk->rate;
/* If this is the PLL base clock, no more calculations needed */
if (clk->pll_data)
- return;
+ return rate;
if (WARN_ON(!clk->parent))
- return;
+ return rate;
- clk->rate = clk->parent->rate;
+ rate = clk->parent->rate;
/* Otherwise, the parent must be a PLL */
if (WARN_ON(!clk->parent->pll_data))
- return;
+ return rate;
pll = clk->parent->pll_data;
/* If pre-PLL, source clock is before the multiplier and divider(s) */
if (clk->flags & PRE_PLL)
- clk->rate = pll->input_rate;
+ rate = pll->input_rate;
if (!clk->div_reg)
- return;
+ return rate;
v = __raw_readl(pll->base + clk->div_reg);
if (v & PLLDIV_EN) {
- plldiv = (v & PLLDIV_RATIO_MASK) + 1;
+ plldiv = (v & pll->div_ratio_mask) + 1;
if (plldiv)
- clk->rate /= plldiv;
+ rate /= plldiv;
+ }
+
+ return rate;
+}
+
+int davinci_set_sysclk_rate(struct clk *clk, unsigned long rate)
+{
+ unsigned v;
+ struct pll_data *pll;
+ unsigned long input;
+ unsigned ratio = 0;
+
+ /* If this is the PLL base clock, wrong function to call */
+ if (clk->pll_data)
+ return -EINVAL;
+
+ /* There must be a parent... */
+ if (WARN_ON(!clk->parent))
+ return -EINVAL;
+
+ /* ... the parent must be a PLL... */
+ if (WARN_ON(!clk->parent->pll_data))
+ return -EINVAL;
+
+ /* ... and this clock must have a divider. */
+ if (WARN_ON(!clk->div_reg))
+ return -EINVAL;
+
+ pll = clk->parent->pll_data;
+
+ input = clk->parent->rate;
+
+ /* If pre-PLL, source clock is before the multiplier and divider(s) */
+ if (clk->flags & PRE_PLL)
+ input = pll->input_rate;
+
+ if (input > rate) {
+ /*
+ * Can afford to provide an output little higher than requested
+ * only if maximum rate supported by hardware on this sysclk
+ * is known.
+ */
+ if (clk->maxrate) {
+ ratio = DIV_ROUND_CLOSEST(input, rate);
+ if (input / ratio > clk->maxrate)
+ ratio = 0;
+ }
+
+ if (ratio == 0)
+ ratio = DIV_ROUND_UP(input, rate);
+
+ ratio--;
}
+
+ if (ratio > pll->div_ratio_mask)
+ return -EINVAL;
+
+ do {
+ v = __raw_readl(pll->base + PLLSTAT);
+ } while (v & PLLSTAT_GOSTAT);
+
+ v = __raw_readl(pll->base + clk->div_reg);
+ v &= ~pll->div_ratio_mask;
+ v |= ratio | PLLDIV_EN;
+ __raw_writel(v, pll->base + clk->div_reg);
+
+ v = __raw_readl(pll->base + PLLCMD);
+ v |= PLLCMD_GOSET;
+ __raw_writel(v, pll->base + PLLCMD);
+
+ do {
+ v = __raw_readl(pll->base + PLLSTAT);
+ } while (v & PLLSTAT_GOSTAT);
+
+ return 0;
+}
+EXPORT_SYMBOL(davinci_set_sysclk_rate);
+
+static unsigned long clk_leafclk_recalc(struct clk *clk)
+{
+ if (WARN_ON(!clk->parent))
+ return clk->rate;
+
+ return clk->parent->rate;
}
-static void __init clk_pll_init(struct clk *clk)
+int davinci_simple_set_rate(struct clk *clk, unsigned long rate)
+{
+ clk->rate = rate;
+ return 0;
+}
+
+static unsigned long clk_pllclk_recalc(struct clk *clk)
{
u32 ctrl, mult = 1, prediv = 1, postdiv = 1;
u8 bypass;
struct pll_data *pll = clk->pll_data;
+ unsigned long rate = clk->rate;
- pll->base = IO_ADDRESS(pll->phys_base);
ctrl = __raw_readl(pll->base + PLLCTL);
- clk->rate = pll->input_rate = clk->parent->rate;
+ rate = pll->input_rate = clk->parent->rate;
if (ctrl & PLLCTL_PLLEN) {
bypass = 0;
@@ -237,7 +428,7 @@ static void __init clk_pll_init(struct clk *clk)
if (pll->flags & PLL_HAS_PREDIV) {
prediv = __raw_readl(pll->base + PREDIV);
if (prediv & PLLDIV_EN)
- prediv = (prediv & PLLDIV_RATIO_MASK) + 1;
+ prediv = (prediv & pll->div_ratio_mask) + 1;
else
prediv = 1;
}
@@ -249,15 +440,15 @@ static void __init clk_pll_init(struct clk *clk)
if (pll->flags & PLL_HAS_POSTDIV) {
postdiv = __raw_readl(pll->base + POSTDIV);
if (postdiv & PLLDIV_EN)
- postdiv = (postdiv & PLLDIV_RATIO_MASK) + 1;
+ postdiv = (postdiv & pll->div_ratio_mask) + 1;
else
postdiv = 1;
}
if (!bypass) {
- clk->rate /= prediv;
- clk->rate *= mult;
- clk->rate /= postdiv;
+ rate /= prediv;
+ rate *= mult;
+ rate /= postdiv;
}
pr_debug("PLL%d: input = %lu MHz [ ",
@@ -270,56 +461,182 @@ static void __init clk_pll_init(struct clk *clk)
pr_debug("* %d ", mult);
if (postdiv > 1)
pr_debug("/ %d ", postdiv);
- pr_debug("] --> %lu MHz output.\n", clk->rate / 1000000);
+ pr_debug("] --> %lu MHz output.\n", rate / 1000000);
+
+ return rate;
}
-int __init davinci_clk_init(struct davinci_clk *clocks)
- {
- struct davinci_clk *c;
+/**
+ * davinci_set_pllrate - set the output rate of a given PLL.
+ *
+ * Note: Currently tested to work with OMAP-L138 only.
+ *
+ * @pll: pll whose rate needs to be changed.
+ * @prediv: The pre divider value. Passing 0 disables the pre-divider.
+ * @pllm: The multiplier value. Passing 0 leads to multiply-by-one.
+ * @postdiv: The post divider value. Passing 0 disables the post-divider.
+ */
+int davinci_set_pllrate(struct pll_data *pll, unsigned int prediv,
+ unsigned int mult, unsigned int postdiv)
+{
+ u32 ctrl;
+ unsigned int locktime;
+ unsigned long flags;
+
+ if (pll->base == NULL)
+ return -EINVAL;
+
+ /*
+ * PLL lock time required per OMAP-L138 datasheet is
+ * (2000 * prediv)/sqrt(pllm) OSCIN cycles. We approximate sqrt(pllm)
+ * as 4 and OSCIN cycle as 25 MHz.
+ */
+ if (prediv) {
+ locktime = ((2000 * prediv) / 100);
+ prediv = (prediv - 1) | PLLDIV_EN;
+ } else {
+ locktime = PLL_LOCK_TIME;
+ }
+ if (postdiv)
+ postdiv = (postdiv - 1) | PLLDIV_EN;
+ if (mult)
+ mult = mult - 1;
+
+ /* Protect against simultaneous calls to PLL setting seqeunce */
+ spin_lock_irqsave(&clockfw_lock, flags);
+
+ ctrl = __raw_readl(pll->base + PLLCTL);
+
+ /* Switch the PLL to bypass mode */
+ ctrl &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ udelay(PLL_BYPASS_TIME);
+
+ /* Reset and enable PLL */
+ ctrl &= ~(PLLCTL_PLLRST | PLLCTL_PLLDIS);
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ if (pll->flags & PLL_HAS_PREDIV)
+ __raw_writel(prediv, pll->base + PREDIV);
+
+ __raw_writel(mult, pll->base + PLLM);
+
+ if (pll->flags & PLL_HAS_POSTDIV)
+ __raw_writel(postdiv, pll->base + POSTDIV);
+
+ udelay(PLL_RESET_TIME);
+
+ /* Bring PLL out of reset */
+ ctrl |= PLLCTL_PLLRST;
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ udelay(locktime);
+
+ /* Remove PLL from bypass mode */
+ ctrl |= PLLCTL_PLLEN;
+ __raw_writel(ctrl, pll->base + PLLCTL);
+
+ spin_unlock_irqrestore(&clockfw_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(davinci_set_pllrate);
+
+/**
+ * davinci_set_refclk_rate() - Set the reference clock rate
+ * @rate: The new rate.
+ *
+ * Sets the reference clock rate to a given value. This will most likely
+ * result in the entire clock tree getting updated.
+ *
+ * This is used to support boards which use a reference clock different
+ * than that used by default in <soc>.c file. The reference clock rate
+ * should be updated early in the boot process; ideally soon after the
+ * clock tree has been initialized once with the default reference clock
+ * rate (davinci_common_init()).
+ *
+ * Returns 0 on success, error otherwise.
+ */
+int davinci_set_refclk_rate(unsigned long rate)
+{
+ struct clk *refclk;
+
+ refclk = clk_get(NULL, "ref");
+ if (IS_ERR(refclk)) {
+ pr_err("%s: failed to get reference clock.\n", __func__);
+ return PTR_ERR(refclk);
+ }
+
+ clk_set_rate(refclk, rate);
+
+ clk_put(refclk);
+
+ return 0;
+}
+
+int __init davinci_clk_init(struct clk_lookup *clocks)
+{
+ struct clk_lookup *c;
struct clk *clk;
+ size_t num_clocks = 0;
- for (c = clocks; c->lk.clk; c++) {
- clk = c->lk.clk;
+ for (c = clocks; c->clk; c++) {
+ clk = c->clk;
- if (clk->pll_data)
- clk_pll_init(clk);
+ if (!clk->recalc) {
- /* Calculate rates for PLL-derived clocks */
- else if (clk->flags & CLK_PLL)
- clk_sysclk_recalc(clk);
+ /* Check if clock is a PLL */
+ if (clk->pll_data)
+ clk->recalc = clk_pllclk_recalc;
+
+ /* Else, if it is a PLL-derived clock */
+ else if (clk->flags & CLK_PLL)
+ clk->recalc = clk_sysclk_recalc;
+
+ /* Otherwise, it is a leaf clock (PSC clock) */
+ else if (clk->parent)
+ clk->recalc = clk_leafclk_recalc;
+ }
+
+ if (clk->pll_data) {
+ struct pll_data *pll = clk->pll_data;
+
+ if (!pll->div_ratio_mask)
+ pll->div_ratio_mask = PLLDIV_RATIO_MASK;
+
+ if (pll->phys_base && !pll->base) {
+ pll->base = ioremap(pll->phys_base, SZ_4K);
+ WARN_ON(!pll->base);
+ }
+ }
+
+ if (clk->recalc)
+ clk->rate = clk->recalc(clk);
if (clk->lpsc)
clk->flags |= CLK_PSC;
- clkdev_add(&c->lk);
+ if (clk->flags & PSC_LRST)
+ clk->reset = davinci_clk_reset;
+
clk_register(clk);
+ num_clocks++;
/* Turn on clocks that Linux doesn't otherwise manage */
if (clk->flags & ALWAYS_ENABLED)
clk_enable(clk);
}
- return 0;
-}
-
-#ifdef CONFIG_PROC_FS
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
+ clkdev_add_table(clocks, num_clocks);
-static void *davinci_ck_start(struct seq_file *m, loff_t *pos)
-{
- return *pos < 1 ? (void *)1 : NULL;
+ return 0;
}
-static void *davinci_ck_next(struct seq_file *m, void *v, loff_t *pos)
-{
- ++*pos;
- return NULL;
-}
+#ifdef CONFIG_DEBUG_FS
-static void davinci_ck_stop(struct seq_file *m, void *v)
-{
-}
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
#define CLKNAME_MAX 10 /* longest clock name */
#define NEST_DELTA 2
@@ -352,49 +669,45 @@ dump_clock(struct seq_file *s, unsigned nest, struct clk *parent)
/* REVISIT show device associations too */
/* cost is now small, but not linear... */
- list_for_each_entry(clk, &clocks, node) {
- if (clk->parent == parent)
- dump_clock(s, nest + NEST_DELTA, clk);
+ list_for_each_entry(clk, &parent->children, childnode) {
+ dump_clock(s, nest + NEST_DELTA, clk);
}
}
static int davinci_ck_show(struct seq_file *m, void *v)
{
- /* Show clock tree; we know the main oscillator is first.
- * We trust nonzero usecounts equate to PSC enables...
+ struct clk *clk;
+
+ /*
+ * Show clock tree; We trust nonzero usecounts equate to PSC enables...
*/
mutex_lock(&clocks_mutex);
- if (!list_empty(&clocks))
- dump_clock(m, 0, list_first_entry(&clocks, struct clk, node));
+ list_for_each_entry(clk, &clocks, node)
+ if (!clk->parent)
+ dump_clock(m, 0, clk);
mutex_unlock(&clocks_mutex);
return 0;
}
-static const struct seq_operations davinci_ck_op = {
- .start = davinci_ck_start,
- .next = davinci_ck_next,
- .stop = davinci_ck_stop,
- .show = davinci_ck_show
-};
-
static int davinci_ck_open(struct inode *inode, struct file *file)
{
- return seq_open(file, &davinci_ck_op);
+ return single_open(file, davinci_ck_show, NULL);
}
-static const struct file_operations proc_davinci_ck_operations = {
+static const struct file_operations davinci_ck_operations = {
.open = davinci_ck_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = seq_release,
+ .release = single_release,
};
-static int __init davinci_ck_proc_init(void)
+static int __init davinci_clk_debugfs_init(void)
{
- proc_create("davinci_clocks", 0, NULL, &proc_davinci_ck_operations);
+ debugfs_create_file("davinci_clocks", S_IFREG | S_IRUGO, NULL, NULL,
+ &davinci_ck_operations);
return 0;
}
-__initcall(davinci_ck_proc_init);
-#endif /* CONFIG_DEBUG_PROC_FS */
+device_initcall(davinci_clk_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */