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Diffstat (limited to 'arch/arm/mach-ep93xx/clock.c')
-rw-r--r--arch/arm/mach-ep93xx/clock.c216
1 files changed, 187 insertions, 29 deletions
diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index 3dd0e2a23095..1d0f9d8aff2e 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;
@@ -37,91 +40,130 @@ struct clk {
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,
};
+static struct clk clk_video = {
+ .sw_locked = 1,
+ .enable_reg = EP93XX_SYSCON_VIDCLKDIV,
+ .enable_mask = EP93XX_SYSCON_CLKDIV_ENABLE,
+ .set_rate = set_div_rate,
+};
+
/* 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,
};
@@ -130,6 +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),
@@ -140,6 +183,7 @@ static struct clk_lookup clocks[] = {
INIT_CK(NULL, "pll2", &clk_pll2),
INIT_CK("ep93xx-ohci", NULL, &clk_usb_host),
INIT_CK("ep93xx-keypad", NULL, &clk_keypad),
+ INIT_CK("ep93xx-fb", NULL, &clk_video),
INIT_CK(NULL, "pwm_clk", &clk_pwm),
INIT_CK(NULL, "m2p0", &clk_m2p0),
INIT_CK(NULL, "m2p1", &clk_m2p1),
@@ -155,48 +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);
+static void __clk_disable(struct clk *clk)
+{
+ 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);
+ }
+
+ if (clk->parent)
+ __clk_disable(clk->parent);
+ }
+}
+
void clk_disable(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;
+
+ 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)
@@ -236,6 +316,84 @@ static int set_keytchclk_rate(struct clk *clk, unsigned long rate)
return 0;
}
+static int calc_clk_div(struct clk *clk, unsigned long rate,
+ int *psel, int *esel, int *pdiv, int *div)
+{
+ 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),
+ clk_xtali.rate / 4);
+ rate = min(rate, max_rate);
+
+ /*
+ * Try the two pll's and the external clock
+ * Because the valid predividers are 2, 2.5 and 3, we multiply
+ * all the clocks by 2 to avoid floating point math.
+ *
+ * This is based on the algorithm in the ep93xx raster guide:
+ * http://be-a-maverick.com/en/pubs/appNote/AN269REV1.pdf
+ *
+ */
+ for (i = 0; i < 3; i++) {
+ if (i == 0)
+ mclk = &clk_xtali;
+ else if (i == 1)
+ mclk = &clk_pll1;
+ else
+ mclk = &clk_pll2;
+ mclk_rate = mclk->rate * 2;
+
+ /* Try each predivider value */
+ for (__pdiv = 4; __pdiv <= 6; __pdiv++) {
+ __div = mclk_rate / (rate * __pdiv);
+ if (__div < 2 || __div > 127)
+ continue;
+
+ actual_rate = mclk_rate / (__pdiv * __div);
+
+ if (!found || abs(actual_rate - rate) < rate_err) {
+ *pdiv = __pdiv - 3;
+ *div = __div;
+ *psel = (i == 2);
+ *esel = (i != 0);
+ clk->parent = mclk;
+ clk->rate = actual_rate;
+ rate_err = abs(actual_rate - rate);
+ found = 1;
+ }
+ }
+ }
+
+ if (!found)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int set_div_rate(struct clk *clk, unsigned long rate)
+{
+ int err, psel = 0, esel = 0, pdiv = 0, div = 0;
+ u32 val;
+
+ 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);
+ val &= ~0x7fff;
+
+ /* Set the new esel, psel, pdiv and div bits for the new clock rate */
+ val |= (esel ? EP93XX_SYSCON_CLKDIV_ESEL : 0) |
+ (psel ? EP93XX_SYSCON_CLKDIV_PSEL : 0) |
+ (pdiv << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | div;
+ ep93xx_syscon_swlocked_write(val, clk->enable_reg);
+ return 0;
+}
+
int clk_set_rate(struct clk *clk, unsigned long rate)
{
if (clk->set_rate)
@@ -258,7 +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 */
@@ -291,7 +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);
}
@@ -302,7 +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 {
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 05:01:14 +0100