1 files changed, 37 insertions, 0 deletions

diff --git a/arch/arm/mach-s3c2440/clock.c b/arch/arm/mach-s3c2440/clock.c
index f9e6bdaf41d2..f85853c5d5eb 100644
--- a/arch/arm/mach-s3c2440/clock.c
+++ b/arch/arm/mach-s3c2440/clock.c
@@ -34,6 +34,7 @@
 #include <linux/mutex.h>
 #include <linux/clk.h>
 #include <linux/io.h>
+#include <linux/serial_core.h>
 
 #include <mach/hardware.h>
 #include <linux/atomic.h>
@@ -43,6 +44,7 @@
 
 #include <plat/clock.h>
 #include <plat/cpu.h>
+#include <plat/regs-serial.h>
 
 /* S3C2440 extended clock support */
 
@@ -108,6 +110,40 @@ static struct clk s3c2440_clk_ac97 = {
         .ctrlbit        = S3C2440_CLKCON_CAMERA,
 };
 
+static unsigned long  s3c2440_fclk_n_getrate(struct clk *clk)
+{
+        unsigned long ucon0, ucon1, ucon2, divisor;
+
+        /* the fun of calculating the uart divisors on the s3c2440 */
+        ucon0 = __raw_readl(S3C24XX_VA_UART0 + S3C2410_UCON);
+        ucon1 = __raw_readl(S3C24XX_VA_UART1 + S3C2410_UCON);
+        ucon2 = __raw_readl(S3C24XX_VA_UART2 + S3C2410_UCON);
+
+        ucon0 &= S3C2440_UCON0_DIVMASK;
+        ucon1 &= S3C2440_UCON1_DIVMASK;
+        ucon2 &= S3C2440_UCON2_DIVMASK;
+
+        if (ucon0 != 0)
+                divisor = (ucon0 >> S3C2440_UCON_DIVSHIFT) + 6;
+        else if (ucon1 != 0)
+                divisor = (ucon1 >> S3C2440_UCON_DIVSHIFT) + 21;
+        else if (ucon2 != 0)
+                divisor = (ucon2 >> S3C2440_UCON_DIVSHIFT) + 36;
+        else
+                /* manual calims 44, seems to be 9 */
+                divisor = 9;
+
+        return clk_get_rate(clk->parent) / divisor;
+}
+
+static struct clk s3c2440_clk_fclk_n = {
+        .name           = "fclk_n",
+        .parent         = &clk_f,
+        .ops            = &(struct clk_ops) {
+                .get_rate       = s3c2440_fclk_n_getrate,
+        },
+};
+
 static int s3c2440_clk_add(struct sys_device *sysdev)
 {
         struct clk *clock_upll;
@@ -126,6 +162,7 @@ static int s3c2440_clk_add(struct sys_device *sysdev)
         s3c2440_clk_cam.parent = clock_h;
         s3c2440_clk_ac97.parent = clock_p;
         s3c2440_clk_cam_upll.parent = clock_upll;
+        s3c24xx_register_clock(&s3c2440_clk_fclk_n);
 
         s3c24xx_register_clock(&s3c2440_clk_ac97);
         s3c24xx_register_clock(&s3c2440_clk_cam);