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-rw-r--r--drivers/clk/imx/clk-vf610.c33
1 files changed, 18 insertions, 15 deletions
diff --git a/drivers/clk/imx/clk-vf610.c b/drivers/clk/imx/clk-vf610.c
index 1b1b881..d70f441 100644
--- a/drivers/clk/imx/clk-vf610.c
+++ b/drivers/clk/imx/clk-vf610.c
@@ -459,26 +459,30 @@ enum {
DDRMC_CR117_AXI0_FITYPEREG_SYNC = 0b01 << 16,
};
-static int vf610_switch_cpu_clock_to_500mhz(void)
+static bool vf610_cpu_clk_changeable(void)
{
- int ret;
-
/*
* When switching A5 CPU to 500Mhz we expect DDRC to be
* clocked by PLL2_PFD2 and the system to be configured in
* asynchronous mode.
- *
- * We also can't just use default PFD1 output of PLL1 due to
- * Errata e6235, so we have to re-clock the PLL itself and use
- * its output to clock the CPU directly.
*/
-
if (clk_get_parent(clk[VF610_CLK_DDR_SEL]) != clk[VF610_CLK_PLL2_PFD2]) {
- pr_warn("DDRC is clocked by PLL1, can't switch CPU clock");
- return -EINVAL;
+ pr_warn("DDRC is clocked by PLL1, can't switch CPU clock\n");
+ return false;
}
+ return true;
+}
+
+static int vf610_switch_cpu_clock_to_500mhz(void)
+{
+ int ret;
+
/*
+ * We can't just use default PFD1 output of PLL1 due to
+ * Errata e6235, so we have to re-clock the PLL itself and use
+ * its output to clock the CPU directly.
+ *
* Code below alters the frequency of PLL1, and doing so would
* require us to wait for PLL1 lock before proceeding to
* select it as a clock source again.
@@ -533,11 +537,6 @@ static int vf610_switch_cpu_clock_to_400mhz(void)
uint32_t cr117;
void * __iomem ddrmc = IOMEM(VF610_DDR_BASE_ADDR);
- if (clk_get_parent(clk[VF610_CLK_DDR_SEL]) != clk[VF610_CLK_PLL2_PFD2]) {
- pr_warn("DDRC is clocked by PLL1, can't switch CPU clock");
- return -EINVAL;
- }
-
ret = clk_set_parent(clk[VF610_CLK_PLL2_PFD_SEL], clk[VF610_CLK_PLL2_PFD2]);
if (ret < 0) {
pr_crit("Unable to re-parent '%s'\n",
@@ -595,10 +594,14 @@ static int vf610_switch_cpu_clock(void)
return 0;
case VF610_SPEED_500:
+ if (!vf610_cpu_clk_changeable())
+ return 0;
ret = vf610_switch_cpu_clock_to_500mhz();
break;
case VF610_SPEED_400:
+ if (!vf610_cpu_clk_changeable())
+ return 0;
ret = vf610_switch_cpu_clock_to_400mhz();
break;
}