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Diffstat (limited to 'arch/arm/mach-omap2/clock.c')
-rw-r--r--arch/arm/mach-omap2/clock.c146
1 files changed, 123 insertions, 23 deletions
diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c
index d1b648a4efbf..0de201c3d50b 100644
--- a/arch/arm/mach-omap2/clock.c
+++ b/arch/arm/mach-omap2/clock.c
@@ -32,10 +32,14 @@
#include "memory.h"
#include "clock.h"
+#undef DEBUG
+
//#define DOWN_VARIABLE_DPLL 1 /* Experimental */
static struct prcm_config *curr_prcm_set;
static u32 curr_perf_level = PRCM_FULL_SPEED;
+static struct clk *vclk;
+static struct clk *sclk;
/*-------------------------------------------------------------------------
* Omap2 specific clock functions
@@ -79,6 +83,14 @@ static void omap2_propagate_rate(struct clk * clk)
propagate_rate(clk);
}
+static void omap2_set_osc_ck(int enable)
+{
+ if (enable)
+ PRCM_CLKSRC_CTRL &= ~(0x3 << 3);
+ else
+ PRCM_CLKSRC_CTRL |= 0x3 << 3;
+}
+
/* Enable an APLL if off */
static void omap2_clk_fixed_enable(struct clk *clk)
{
@@ -101,12 +113,54 @@ static void omap2_clk_fixed_enable(struct clk *clk)
else if (clk == &apll54_ck)
cval = (1 << 6);
- while (!CM_IDLEST_CKGEN & cval) { /* Wait for lock */
+ while (!(CM_IDLEST_CKGEN & cval)) { /* Wait for lock */
++i;
udelay(1);
- if (i == 100000)
+ if (i == 100000) {
+ printk(KERN_ERR "Clock %s didn't lock\n", clk->name);
+ break;
+ }
+ }
+}
+
+static void omap2_clk_wait_ready(struct clk *clk)
+{
+ unsigned long reg, other_reg, st_reg;
+ u32 bit;
+ int i;
+
+ reg = (unsigned long) clk->enable_reg;
+ if (reg == (unsigned long) &CM_FCLKEN1_CORE ||
+ reg == (unsigned long) &CM_FCLKEN2_CORE)
+ other_reg = (reg & ~0xf0) | 0x10;
+ else if (reg == (unsigned long) &CM_ICLKEN1_CORE ||
+ reg == (unsigned long) &CM_ICLKEN2_CORE)
+ other_reg = (reg & ~0xf0) | 0x00;
+ else
+ return;
+
+ /* No check for DSS or cam clocks */
+ if ((reg & 0x0f) == 0) {
+ if (clk->enable_bit <= 1 || clk->enable_bit == 31)
+ return;
+ }
+
+ /* Check if both functional and interface clocks
+ * are running. */
+ bit = 1 << clk->enable_bit;
+ if (!(__raw_readl(other_reg) & bit))
+ return;
+ st_reg = (other_reg & ~0xf0) | 0x20;
+ i = 0;
+ while (!(__raw_readl(st_reg) & bit)) {
+ i++;
+ if (i == 100000) {
+ printk(KERN_ERR "Timeout enabling clock %s\n", clk->name);
break;
+ }
}
+ if (i)
+ pr_debug("Clock %s stable after %d loops\n", clk->name, i);
}
/* Enables clock without considering parent dependencies or use count
@@ -119,6 +173,11 @@ static int _omap2_clk_enable(struct clk * clk)
if (clk->flags & ALWAYS_ENABLED)
return 0;
+ if (unlikely(clk == &osc_ck)) {
+ omap2_set_osc_ck(1);
+ return 0;
+ }
+
if (unlikely(clk->enable_reg == 0)) {
printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
clk->name);
@@ -133,6 +192,9 @@ static int _omap2_clk_enable(struct clk * clk)
regval32 = __raw_readl(clk->enable_reg);
regval32 |= (1 << clk->enable_bit);
__raw_writel(regval32, clk->enable_reg);
+ wmb();
+
+ omap2_clk_wait_ready(clk);
return 0;
}
@@ -155,6 +217,11 @@ static void _omap2_clk_disable(struct clk *clk)
{
u32 regval32;
+ if (unlikely(clk == &osc_ck)) {
+ omap2_set_osc_ck(0);
+ return;
+ }
+
if (clk->enable_reg == 0)
return;
@@ -166,6 +233,7 @@ static void _omap2_clk_disable(struct clk *clk)
regval32 = __raw_readl(clk->enable_reg);
regval32 &= ~(1 << clk->enable_bit);
__raw_writel(regval32, clk->enable_reg);
+ wmb();
}
static int omap2_clk_enable(struct clk *clk)
@@ -695,12 +763,14 @@ static int omap2_clk_set_rate(struct clk *clk, unsigned long rate)
reg_val = __raw_readl(reg);
reg_val &= ~(field_mask << div_off);
reg_val |= (field_val << div_off);
-
__raw_writel(reg_val, reg);
+ wmb();
clk->rate = clk->parent->rate / field_val;
- if (clk->flags & DELAYED_APP)
+ if (clk->flags & DELAYED_APP) {
__raw_writel(0x1, (void __iomem *)&PRCM_CLKCFG_CTRL);
+ wmb();
+ }
ret = 0;
} else if (clk->set_rate != 0)
ret = clk->set_rate(clk, rate);
@@ -836,10 +906,12 @@ static int omap2_clk_set_parent(struct clk *clk, struct clk *new_parent)
reg_val = __raw_readl(reg) & ~(field_mask << src_off);
reg_val |= (field_val << src_off);
__raw_writel(reg_val, reg);
+ wmb();
- if (clk->flags & DELAYED_APP)
+ if (clk->flags & DELAYED_APP) {
__raw_writel(0x1, (void __iomem *)&PRCM_CLKCFG_CTRL);
-
+ wmb();
+ }
if (clk->usecount > 0)
_omap2_clk_enable(clk);
@@ -953,12 +1025,29 @@ static int omap2_select_table_rate(struct clk * clk, unsigned long rate)
* Omap2 clock reset and init functions
*-------------------------------------------------------------------------*/
+#ifdef CONFIG_OMAP_RESET_CLOCKS
+static void __init omap2_clk_disable_unused(struct clk *clk)
+{
+ u32 regval32;
+
+ regval32 = __raw_readl(clk->enable_reg);
+ if ((regval32 & (1 << clk->enable_bit)) == 0)
+ return;
+
+ printk(KERN_INFO "Disabling unused clock \"%s\"\n", clk->name);
+ _omap2_clk_disable(clk);
+}
+#else
+#define omap2_clk_disable_unused NULL
+#endif
+
static struct clk_functions omap2_clk_functions = {
.clk_enable = omap2_clk_enable,
.clk_disable = omap2_clk_disable,
.clk_round_rate = omap2_clk_round_rate,
.clk_set_rate = omap2_clk_set_rate,
.clk_set_parent = omap2_clk_set_parent,
+ .clk_disable_unused = omap2_clk_disable_unused,
};
static void __init omap2_get_crystal_rate(struct clk *osc, struct clk *sys)
@@ -984,27 +1073,19 @@ static void __init omap2_get_crystal_rate(struct clk *osc, struct clk *sys)
sys->rate = sclk;
}
-#ifdef CONFIG_OMAP_RESET_CLOCKS
-static void __init omap2_disable_unused_clocks(void)
+/*
+ * Set clocks for bypass mode for reboot to work.
+ */
+void omap2_clk_prepare_for_reboot(void)
{
- struct clk *ck;
- u32 regval32;
+ u32 rate;
- list_for_each_entry(ck, &clocks, node) {
- if (ck->usecount > 0 || (ck->flags & ALWAYS_ENABLED) ||
- ck->enable_reg == 0)
- continue;
-
- regval32 = __raw_readl(ck->enable_reg);
- if ((regval32 & (1 << ck->enable_bit)) == 0)
- continue;
+ if (vclk == NULL || sclk == NULL)
+ return;
- printk(KERN_INFO "Disabling unused clock \"%s\"\n", ck->name);
- _omap2_clk_disable(ck);
- }
+ rate = clk_get_rate(sclk);
+ clk_set_rate(vclk, rate);
}
-late_initcall(omap2_disable_unused_clocks);
-#endif
/*
* Switch the MPU rate if specified on cmdline.
@@ -1077,8 +1158,27 @@ int __init omap2_clk_init(void)
*/
clk_enable(&sync_32k_ick);
clk_enable(&omapctrl_ick);
+
+ /* Force the APLLs active during bootup to avoid disabling and
+ * enabling them unnecessarily. */
+ clk_enable(&apll96_ck);
+ clk_enable(&apll54_ck);
+
if (cpu_is_omap2430())
clk_enable(&sdrc_ick);
+ /* Avoid sleeping sleeping during omap2_clk_prepare_for_reboot() */
+ vclk = clk_get(NULL, "virt_prcm_set");
+ sclk = clk_get(NULL, "sys_ck");
+
+ return 0;
+}
+
+static int __init omap2_disable_aplls(void)
+{
+ clk_disable(&apll96_ck);
+ clk_disable(&apll54_ck);
+
return 0;
}
+late_initcall(omap2_disable_aplls);