summaryrefslogtreecommitdiffstats
path: root/arch/arc/plat-hsdk/platform.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arc/plat-hsdk/platform.c')
-rw-r--r--arch/arc/plat-hsdk/platform.c42
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/arc/plat-hsdk/platform.c b/arch/arc/plat-hsdk/platform.c
index a2e7fd17e36d..744e62e58788 100644
--- a/arch/arc/plat-hsdk/platform.c
+++ b/arch/arc/plat-hsdk/platform.c
@@ -38,6 +38,42 @@ static void __init hsdk_init_per_cpu(unsigned int cpu)
#define CREG_PAE (CREG_BASE + 0x180)
#define CREG_PAE_UPDATE (CREG_BASE + 0x194)
+#define CREG_CORE_IF_CLK_DIV (CREG_BASE + 0x4B8)
+#define CREG_CORE_IF_CLK_DIV_2 0x1
+#define CGU_BASE ARC_PERIPHERAL_BASE
+#define CGU_PLL_STATUS (ARC_PERIPHERAL_BASE + 0x4)
+#define CGU_PLL_CTRL (ARC_PERIPHERAL_BASE + 0x0)
+#define CGU_PLL_STATUS_LOCK BIT(0)
+#define CGU_PLL_STATUS_ERR BIT(1)
+#define CGU_PLL_CTRL_1GHZ 0x3A10
+#define HSDK_PLL_LOCK_TIMEOUT 500
+
+#define HSDK_PLL_LOCKED() \
+ !!(ioread32((void __iomem *) CGU_PLL_STATUS) & CGU_PLL_STATUS_LOCK)
+
+#define HSDK_PLL_ERR() \
+ !!(ioread32((void __iomem *) CGU_PLL_STATUS) & CGU_PLL_STATUS_ERR)
+
+static void __init hsdk_set_cpu_freq_1ghz(void)
+{
+ u32 timeout = HSDK_PLL_LOCK_TIMEOUT;
+
+ /*
+ * As we set cpu clock which exceeds 500MHz, the divider for the interface
+ * clock must be programmed to div-by-2.
+ */
+ iowrite32(CREG_CORE_IF_CLK_DIV_2, (void __iomem *) CREG_CORE_IF_CLK_DIV);
+
+ /* Set cpu clock to 1GHz */
+ iowrite32(CGU_PLL_CTRL_1GHZ, (void __iomem *) CGU_PLL_CTRL);
+
+ while (!HSDK_PLL_LOCKED() && timeout--)
+ cpu_relax();
+
+ if (!HSDK_PLL_LOCKED() || HSDK_PLL_ERR())
+ pr_err("Failed to setup CPU frequency to 1GHz!");
+}
+
static void __init hsdk_init_early(void)
{
/*
@@ -52,6 +88,12 @@ static void __init hsdk_init_early(void)
/* Really apply settings made above */
writel(1, (void __iomem *) CREG_PAE_UPDATE);
+
+ /*
+ * Setup CPU frequency to 1GHz.
+ * TODO: remove it after smart hsdk pll driver will be introduced.
+ */
+ hsdk_set_cpu_freq_1ghz();
}
static const char *hsdk_compat[] __initconst = {
OpenPOWER on IntegriCloud