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Diffstat (limited to 'arch/arm/mach-s3c2410/s3c2440-clock.c')
-rw-r--r--arch/arm/mach-s3c2410/s3c2440-clock.c89
1 files changed, 71 insertions, 18 deletions
diff --git a/arch/arm/mach-s3c2410/s3c2440-clock.c b/arch/arm/mach-s3c2410/s3c2440-clock.c
index b557a2be8a0..57a15974d4b 100644
--- a/arch/arm/mach-s3c2410/s3c2440-clock.c
+++ b/arch/arm/mach-s3c2410/s3c2440-clock.c
@@ -31,6 +31,7 @@
#include <linux/sysdev.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
+#include <linux/mutex.h>
#include <linux/clk.h>
#include <asm/hardware.h>
@@ -45,10 +46,47 @@
/* S3C2440 extended clock support */
-static struct clk s3c2440_clk_upll = {
- .name = "upll",
- .id = -1,
-};
+static unsigned long s3c2440_camif_upll_round(struct clk *clk,
+ unsigned long rate)
+{
+ unsigned long parent_rate = clk_get_rate(clk->parent);
+ int div;
+
+ if (rate > parent_rate)
+ return parent_rate;
+
+ /* note, we remove the +/- 1 calculations for the divisor */
+
+ div = (parent_rate / rate) / 2;
+
+ if (div < 1)
+ div = 1;
+ else if (div > 16)
+ div = 16;
+
+ return parent_rate / (div * 2);
+}
+
+static int s3c2440_camif_upll_setrate(struct clk *clk, unsigned long rate)
+{
+ unsigned long parent_rate = clk_get_rate(clk->parent);
+ unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN);
+
+ rate = s3c2440_camif_upll_round(clk, rate);
+
+ camdivn &= ~(S3C2440_CAMDIVN_CAMCLK_SEL | S3C2440_CAMDIVN_CAMCLK_MASK);
+
+ if (rate != parent_rate) {
+ camdivn |= S3C2440_CAMDIVN_CAMCLK_SEL;
+ camdivn |= (((parent_rate / rate) / 2) - 1);
+ }
+
+ __raw_writel(camdivn, S3C2440_CAMDIVN);
+
+ return 0;
+}
+
+/* Extra S3C2440 clocks */
static struct clk s3c2440_clk_cam = {
.name = "camif",
@@ -57,6 +95,13 @@ static struct clk s3c2440_clk_cam = {
.ctrlbit = S3C2440_CLKCON_CAMERA,
};
+static struct clk s3c2440_clk_cam_upll = {
+ .name = "camif-upll",
+ .id = -1,
+ .set_rate = s3c2440_camif_upll_setrate,
+ .round_rate = s3c2440_camif_upll_round,
+};
+
static struct clk s3c2440_clk_ac97 = {
.name = "ac97",
.id = -1,
@@ -66,38 +111,46 @@ static struct clk s3c2440_clk_ac97 = {
static int s3c2440_clk_add(struct sys_device *sysdev)
{
- unsigned long upllcon = __raw_readl(S3C2410_UPLLCON);
unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN);
+ unsigned long clkdivn;
struct clk *clk_h;
struct clk *clk_p;
- struct clk *clk_xtal;
-
- clk_xtal = clk_get(NULL, "xtal");
- if (IS_ERR(clk_xtal)) {
- printk(KERN_ERR "S3C2440: Failed to get clk_xtal\n");
- return -EINVAL;
- }
-
- s3c2440_clk_upll.rate = s3c2410_get_pll(upllcon, clk_xtal->rate);
+ struct clk *clk_upll;
- printk("S3C2440: Clock Support, UPLL %ld.%03ld MHz, DVS %s\n",
- print_mhz(s3c2440_clk_upll.rate),
+ printk("S3C2440: Clock Support, DVS %s\n",
(camdivn & S3C2440_CAMDIVN_DVSEN) ? "on" : "off");
clk_p = clk_get(NULL, "pclk");
clk_h = clk_get(NULL, "hclk");
+ clk_upll = clk_get(NULL, "upll");
- if (IS_ERR(clk_p) || IS_ERR(clk_h)) {
+ if (IS_ERR(clk_p) || IS_ERR(clk_h) || IS_ERR(clk_upll)) {
printk(KERN_ERR "S3C2440: Failed to get parent clocks\n");
return -EINVAL;
}
+ /* check rate of UPLL, and if it is near 96MHz, then change
+ * to using half the UPLL rate for the system */
+
+ if (clk_get_rate(clk_upll) > (94 * MHZ)) {
+ clk_usb_bus.rate = clk_get_rate(clk_upll) / 2;
+
+ mutex_lock(&clocks_mutex);
+
+ clkdivn = __raw_readl(S3C2410_CLKDIVN);
+ clkdivn |= S3C2440_CLKDIVN_UCLK;
+ __raw_writel(camdivn, S3C2410_CLKDIVN);
+
+ mutex_unlock(&clocks_mutex);
+ }
+
s3c2440_clk_cam.parent = clk_h;
s3c2440_clk_ac97.parent = clk_p;
+ s3c2440_clk_cam_upll.parent = clk_upll;
s3c24xx_register_clock(&s3c2440_clk_ac97);
s3c24xx_register_clock(&s3c2440_clk_cam);
- s3c24xx_register_clock(&s3c2440_clk_upll);
+ s3c24xx_register_clock(&s3c2440_clk_cam_upll);
clk_disable(&s3c2440_clk_ac97);
clk_disable(&s3c2440_clk_cam);