ARM: shmobile: r8a73a4: wait for completion when kicking the clock

[linux-beck.git] / arch / arm / mach-shmobile / clock-r8a73a4.c

diff --git a/arch/arm/mach-shmobile/clock-r8a73a4.c b/arch/arm/mach-shmobile/clock-r8a73a4.c
index 5f7fe628b8a1fbbc4cee40d633353177ad29e310..d5176d0861b53972b882f407357ab81c834cfc48 100644 (file)
--- a/arch/arm/mach-shmobile/clock-r8a73a4.c
+++ b/arch/arm/mach-shmobile/clock-r8a73a4.c
@@ -184,6 +184,21 @@ PLL_CLOCK(pll2h_clk, &main_div2_clk, pll_parent_main_extal, 3, 5, PLL2HCR, 5);
 
 SH_FIXED_RATIO_CLK(pll1_div2_clk,      pll1_clk,       div2);
 
+static int frqcr_kick_do(struct clk *clk)
+{
+       int i;
+
+       /* set KICK bit in FRQCRB to update hardware setting, check success */
+       iowrite32(ioread32(CPG_MAP(FRQCRB)) | BIT(31), CPG_MAP(FRQCRB));
+       for (i = 1000; i; i--)
+               if (ioread32(CPG_MAP(FRQCRB)) & BIT(31))
+                       cpu_relax();
+               else
+                       return 0;
+
+       return -ETIMEDOUT;
+}
+
 static struct clk *main_clks[] = {
        &extalr_clk,
        &extal1_clk,
@@ -205,12 +220,7 @@ static struct clk *main_clks[] = {
 /* DIV4 */
 static void div4_kick(struct clk *clk)
 {
-       unsigned long value;
-
-       /* set KICK bit in FRQCRB to update hardware setting */
-       value = ioread32(CPG_MAP(FRQCRB));
-       value |= (1 << 31);
-       iowrite32(value, CPG_MAP(FRQCRB));
+       frqcr_kick_do(clk);
 }
 
 static int divisors[] = { 2, 3, 4, 6, 8, 12, 16, 18, 24, 0, 36, 48, 10};