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Diffstat (limited to 'arch/arm/mach-ep93xx/clock.c')
-rw-r--r--arch/arm/mach-ep93xx/clock.c166
1 files changed, 119 insertions, 47 deletions
diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index dda19cd7..1d0f9d8 100644
--- a/arch/arm/mach-ep93xx/clock.c
+++ b/arch/arm/mach-ep93xx/clock.c
@@ -16,13 +16,16 @@
#include <linux/module.h>
#include <linux/string.h>
#include <linux/io.h>
+#include <linux/spinlock.h>
+
+#include <mach/hardware.h>
#include <asm/clkdev.h>
#include <asm/div64.h>
-#include <mach/hardware.h>
struct clk {
+ struct clk *parent;
unsigned long rate;
int users;
int sw_locked;
@@ -39,40 +42,60 @@ static unsigned long get_uart_rate(struct clk *clk);
static int set_keytchclk_rate(struct clk *clk, unsigned long rate);
static int set_div_rate(struct clk *clk, unsigned long rate);
+
+static struct clk clk_xtali = {
+ .rate = EP93XX_EXT_CLK_RATE,
+};
static struct clk clk_uart1 = {
+ .parent = &clk_xtali,
.sw_locked = 1,
.enable_reg = EP93XX_SYSCON_DEVCFG,
.enable_mask = EP93XX_SYSCON_DEVCFG_U1EN,
.get_rate = get_uart_rate,
};
static struct clk clk_uart2 = {
+ .parent = &clk_xtali,
.sw_locked = 1,
.enable_reg = EP93XX_SYSCON_DEVCFG,
.enable_mask = EP93XX_SYSCON_DEVCFG_U2EN,
.get_rate = get_uart_rate,
};
static struct clk clk_uart3 = {
+ .parent = &clk_xtali,
.sw_locked = 1,
.enable_reg = EP93XX_SYSCON_DEVCFG,
.enable_mask = EP93XX_SYSCON_DEVCFG_U3EN,
.get_rate = get_uart_rate,
};
-static struct clk clk_pll1;
-static struct clk clk_f;
-static struct clk clk_h;
-static struct clk clk_p;
-static struct clk clk_pll2;
+static struct clk clk_pll1 = {
+ .parent = &clk_xtali,
+};
+static struct clk clk_f = {
+ .parent = &clk_pll1,
+};
+static struct clk clk_h = {
+ .parent = &clk_pll1,
+};
+static struct clk clk_p = {
+ .parent = &clk_pll1,
+};
+static struct clk clk_pll2 = {
+ .parent = &clk_xtali,
+};
static struct clk clk_usb_host = {
+ .parent = &clk_pll2,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_USH_EN,
};
static struct clk clk_keypad = {
+ .parent = &clk_xtali,
.sw_locked = 1,
.enable_reg = EP93XX_SYSCON_KEYTCHCLKDIV,
.enable_mask = EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
.set_rate = set_keytchclk_rate,
};
static struct clk clk_pwm = {
+ .parent = &clk_xtali,
.rate = EP93XX_EXT_CLK_RATE,
};
@@ -85,50 +108,62 @@ static struct clk clk_video = {
/* DMA Clocks */
static struct clk clk_m2p0 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P0,
};
static struct clk clk_m2p1 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P1,
};
static struct clk clk_m2p2 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P2,
};
static struct clk clk_m2p3 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P3,
};
static struct clk clk_m2p4 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P4,
};
static struct clk clk_m2p5 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P5,
};
static struct clk clk_m2p6 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P6,
};
static struct clk clk_m2p7 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P7,
};
static struct clk clk_m2p8 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P8,
};
static struct clk clk_m2p9 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2P9,
};
static struct clk clk_m2m0 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2M0,
};
static struct clk clk_m2m1 = {
+ .parent = &clk_h,
.enable_reg = EP93XX_SYSCON_PWRCNT,
.enable_mask = EP93XX_SYSCON_PWRCNT_DMA_M2M1,
};
@@ -137,6 +172,7 @@ static struct clk clk_m2m1 = {
{ .dev_id = dev, .con_id = con, .clk = ck }
static struct clk_lookup clocks[] = {
+ INIT_CK(NULL, "xtali", &clk_xtali),
INIT_CK("apb:uart1", NULL, &clk_uart1),
INIT_CK("apb:uart2", NULL, &clk_uart2),
INIT_CK("apb:uart3", NULL, &clk_uart3),
@@ -163,48 +199,84 @@ static struct clk_lookup clocks[] = {
INIT_CK(NULL, "m2m1", &clk_m2m1),
};
+static DEFINE_SPINLOCK(clk_lock);
+
+static void __clk_enable(struct clk *clk)
+{
+ if (!clk->users++) {
+ if (clk->parent)
+ __clk_enable(clk->parent);
+
+ if (clk->enable_reg) {
+ u32 v;
+
+ v = __raw_readl(clk->enable_reg);
+ v |= clk->enable_mask;
+ if (clk->sw_locked)
+ ep93xx_syscon_swlocked_write(v, clk->enable_reg);
+ else
+ __raw_writel(v, clk->enable_reg);
+ }
+ }
+}
int clk_enable(struct clk *clk)
{
- if (!clk->users++ && clk->enable_reg) {
- u32 value;
+ unsigned long flags;
- value = __raw_readl(clk->enable_reg);
- value |= clk->enable_mask;
- if (clk->sw_locked)
- ep93xx_syscon_swlocked_write(value, clk->enable_reg);
- else
- __raw_writel(value, clk->enable_reg);
- }
+ if (!clk)
+ return -EINVAL;
+
+ spin_lock_irqsave(&clk_lock, flags);
+ __clk_enable(clk);
+ spin_unlock_irqrestore(&clk_lock, flags);
return 0;
}
EXPORT_SYMBOL(clk_enable);
-void clk_disable(struct clk *clk)
+static void __clk_disable(struct clk *clk)
{
- if (!--clk->users && clk->enable_reg) {
- u32 value;
+ if (!--clk->users) {
+ if (clk->enable_reg) {
+ u32 v;
+
+ v = __raw_readl(clk->enable_reg);
+ v &= ~clk->enable_mask;
+ if (clk->sw_locked)
+ ep93xx_syscon_swlocked_write(v, clk->enable_reg);
+ else
+ __raw_writel(v, clk->enable_reg);
+ }
- value = __raw_readl(clk->enable_reg);
- value &= ~clk->enable_mask;
- if (clk->sw_locked)
- ep93xx_syscon_swlocked_write(value, clk->enable_reg);
- else
- __raw_writel(value, clk->enable_reg);
+ if (clk->parent)
+ __clk_disable(clk->parent);
}
}
+
+void clk_disable(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (!clk)
+ return;
+
+ spin_lock_irqsave(&clk_lock, flags);
+ __clk_disable(clk);
+ spin_unlock_irqrestore(&clk_lock, flags);
+}
EXPORT_SYMBOL(clk_disable);
static unsigned long get_uart_rate(struct clk *clk)
{
+ unsigned long rate = clk_get_rate(clk->parent);
u32 value;
value = __raw_readl(EP93XX_SYSCON_PWRCNT);
if (value & EP93XX_SYSCON_PWRCNT_UARTBAUD)
- return EP93XX_EXT_CLK_RATE;
+ return rate;
else
- return EP93XX_EXT_CLK_RATE / 2;
+ return rate / 2;
}
unsigned long clk_get_rate(struct clk *clk)
@@ -244,16 +316,16 @@ static int set_keytchclk_rate(struct clk *clk, unsigned long rate)
return 0;
}
-static unsigned long calc_clk_div(unsigned long rate, int *psel, int *esel,
- int *pdiv, int *div)
+static int calc_clk_div(struct clk *clk, unsigned long rate,
+ int *psel, int *esel, int *pdiv, int *div)
{
- unsigned long max_rate, best_rate = 0,
- actual_rate = 0, mclk_rate = 0, rate_err = -1;
+ struct clk *mclk;
+ unsigned long max_rate, actual_rate, mclk_rate, rate_err = -1;
int i, found = 0, __div = 0, __pdiv = 0;
/* Don't exceed the maximum rate */
max_rate = max(max(clk_pll1.rate / 4, clk_pll2.rate / 4),
- (unsigned long)EP93XX_EXT_CLK_RATE / 4);
+ clk_xtali.rate / 4);
rate = min(rate, max_rate);
/*
@@ -267,11 +339,12 @@ static unsigned long calc_clk_div(unsigned long rate, int *psel, int *esel,
*/
for (i = 0; i < 3; i++) {
if (i == 0)
- mclk_rate = EP93XX_EXT_CLK_RATE * 2;
+ mclk = &clk_xtali;
else if (i == 1)
- mclk_rate = clk_pll1.rate * 2;
- else if (i == 2)
- mclk_rate = clk_pll2.rate * 2;
+ mclk = &clk_pll1;
+ else
+ mclk = &clk_pll2;
+ mclk_rate = mclk->rate * 2;
/* Try each predivider value */
for (__pdiv = 4; __pdiv <= 6; __pdiv++) {
@@ -286,7 +359,8 @@ static unsigned long calc_clk_div(unsigned long rate, int *psel, int *esel,
*div = __div;
*psel = (i == 2);
*esel = (i != 0);
- best_rate = actual_rate;
+ clk->parent = mclk;
+ clk->rate = actual_rate;
rate_err = abs(actual_rate - rate);
found = 1;
}
@@ -294,21 +368,19 @@ static unsigned long calc_clk_div(unsigned long rate, int *psel, int *esel,
}
if (!found)
- return 0;
+ return -EINVAL;
- return best_rate;
+ return 0;
}
static int set_div_rate(struct clk *clk, unsigned long rate)
{
- unsigned long actual_rate;
- int psel = 0, esel = 0, pdiv = 0, div = 0;
+ int err, psel = 0, esel = 0, pdiv = 0, div = 0;
u32 val;
- actual_rate = calc_clk_div(rate, &psel, &esel, &pdiv, &div);
- if (actual_rate == 0)
- return -EINVAL;
- clk->rate = actual_rate;
+ err = calc_clk_div(clk, rate, &psel, &esel, &pdiv, &div);
+ if (err)
+ return err;
/* Clear the esel, psel, pdiv and div bits */
val = __raw_readl(clk->enable_reg);
@@ -344,7 +416,7 @@ static unsigned long calc_pll_rate(u32 config_word)
unsigned long long rate;
int i;
- rate = EP93XX_EXT_CLK_RATE;
+ rate = clk_xtali.rate;
rate *= ((config_word >> 11) & 0x1f) + 1; /* X1FBD */
rate *= ((config_word >> 5) & 0x3f) + 1; /* X2FBD */
do_div(rate, (config_word & 0x1f) + 1); /* X2IPD */
@@ -377,7 +449,7 @@ static int __init ep93xx_clock_init(void)
value = __raw_readl(EP93XX_SYSCON_CLOCK_SET1);
if (!(value & 0x00800000)) { /* PLL1 bypassed? */
- clk_pll1.rate = EP93XX_EXT_CLK_RATE;
+ clk_pll1.rate = clk_xtali.rate;
} else {
clk_pll1.rate = calc_pll_rate(value);
}
@@ -388,7 +460,7 @@ static int __init ep93xx_clock_init(void)
value = __raw_readl(EP93XX_SYSCON_CLOCK_SET2);
if (!(value & 0x00080000)) { /* PLL2 bypassed? */
- clk_pll2.rate = EP93XX_EXT_CLK_RATE;
+ clk_pll2.rate = clk_xtali.rate;
} else if (value & 0x00040000) { /* PLL2 enabled? */
clk_pll2.rate = calc_pll_rate(value);
} else {
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