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authorStephen Boyd <sboyd@codeaurora.org>2015-08-26 01:55:28 +0300
committerStephen Boyd <sboyd@codeaurora.org>2015-08-26 01:55:28 +0300
commita7c602bf42f943e717eed92165ebfa6dbaba3029 (patch)
tree3c32bc1572acb102ba86c53005ca83cf0c632fd1 /drivers/clk/tegra/clk-tegra124.c
parent1c4b4b0eb1909010b8ebda1ef208bf3ed62e7487 (diff)
parent79cf95c763a11d4b365cd5a627fd1ab4dca67890 (diff)
downloadlinux-a7c602bf42f943e717eed92165ebfa6dbaba3029.tar.xz
Merge tag 'tegra-for-4.3-clk' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into clk-next
clk: tegra: Changes for v4.3-rc1 This contains the DFLL driver needed to implement CPU frequency scaling on Tegra.
Diffstat (limited to 'drivers/clk/tegra/clk-tegra124.c')
-rw-r--r--drivers/clk/tegra/clk-tegra124.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/clk/tegra/clk-tegra124.c b/drivers/clk/tegra/clk-tegra124.c
index 0c44cc7f8558..a9e2b30737ec 100644
--- a/drivers/clk/tegra/clk-tegra124.c
+++ b/drivers/clk/tegra/clk-tegra124.c
@@ -23,6 +23,7 @@
#include <linux/export.h>
#include <linux/clk/tegra.h>
#include <dt-bindings/clock/tegra124-car.h>
+#include <dt-bindings/reset/tegra124-car.h>
#include "clk.h"
#include "clk-id.h"
@@ -38,6 +39,9 @@
#define CLK_SOURCE_CSITE 0x1d4
#define CLK_SOURCE_EMC 0x19c
+#define RST_DFLL_DVCO 0x2f4
+#define DVFS_DFLL_RESET_SHIFT 0
+
#define PLLC_BASE 0x80
#define PLLC_OUT 0x84
#define PLLC_MISC2 0x88
@@ -93,6 +97,8 @@
#define PMC_PLLM_WB0_OVERRIDE 0x1dc
#define PMC_PLLM_WB0_OVERRIDE_2 0x2b0
+#define CCLKG_BURST_POLICY 0x368
+
#define UTMIP_PLL_CFG2 0x488
#define UTMIP_PLL_CFG2_STABLE_COUNT(x) (((x) & 0xffff) << 6)
#define UTMIP_PLL_CFG2_ACTIVE_DLY_COUNT(x) (((x) & 0x3f) << 18)
@@ -125,6 +131,8 @@
#ifdef CONFIG_PM_SLEEP
static struct cpu_clk_suspend_context {
u32 clk_csite_src;
+ u32 cclkg_burst;
+ u32 cclkg_divider;
} tegra124_cpu_clk_sctx;
#endif
@@ -1318,12 +1326,22 @@ static void tegra124_cpu_clock_suspend(void)
tegra124_cpu_clk_sctx.clk_csite_src =
readl(clk_base + CLK_SOURCE_CSITE);
writel(3 << 30, clk_base + CLK_SOURCE_CSITE);
+
+ tegra124_cpu_clk_sctx.cclkg_burst =
+ readl(clk_base + CCLKG_BURST_POLICY);
+ tegra124_cpu_clk_sctx.cclkg_divider =
+ readl(clk_base + CCLKG_BURST_POLICY + 4);
}
static void tegra124_cpu_clock_resume(void)
{
writel(tegra124_cpu_clk_sctx.clk_csite_src,
clk_base + CLK_SOURCE_CSITE);
+
+ writel(tegra124_cpu_clk_sctx.cclkg_burst,
+ clk_base + CCLKG_BURST_POLICY);
+ writel(tegra124_cpu_clk_sctx.cclkg_divider,
+ clk_base + CCLKG_BURST_POLICY + 4);
}
#endif
@@ -1414,6 +1432,68 @@ static void __init tegra124_clock_apply_init_table(void)
}
/**
+ * tegra124_car_barrier - wait for pending writes to the CAR to complete
+ *
+ * Wait for any outstanding writes to the CAR MMIO space from this CPU
+ * to complete before continuing execution. No return value.
+ */
+static void tegra124_car_barrier(void)
+{
+ readl_relaxed(clk_base + RST_DFLL_DVCO);
+}
+
+/**
+ * tegra124_clock_assert_dfll_dvco_reset - assert the DFLL's DVCO reset
+ *
+ * Assert the reset line of the DFLL's DVCO. No return value.
+ */
+void tegra124_clock_assert_dfll_dvco_reset(void)
+{
+ u32 v;
+
+ v = readl_relaxed(clk_base + RST_DFLL_DVCO);
+ v |= (1 << DVFS_DFLL_RESET_SHIFT);
+ writel_relaxed(v, clk_base + RST_DFLL_DVCO);
+ tegra124_car_barrier();
+}
+
+/**
+ * tegra124_clock_deassert_dfll_dvco_reset - deassert the DFLL's DVCO reset
+ *
+ * Deassert the reset line of the DFLL's DVCO, allowing the DVCO to
+ * operate. No return value.
+ */
+void tegra124_clock_deassert_dfll_dvco_reset(void)
+{
+ u32 v;
+
+ v = readl_relaxed(clk_base + RST_DFLL_DVCO);
+ v &= ~(1 << DVFS_DFLL_RESET_SHIFT);
+ writel_relaxed(v, clk_base + RST_DFLL_DVCO);
+ tegra124_car_barrier();
+}
+
+int tegra124_reset_assert(unsigned long id)
+{
+ if (id == TEGRA124_RST_DFLL_DVCO)
+ tegra124_clock_assert_dfll_dvco_reset();
+ else
+ return -EINVAL;
+
+ return 0;
+}
+
+int tegra124_reset_deassert(unsigned long id)
+{
+ if (id == TEGRA124_RST_DFLL_DVCO)
+ tegra124_clock_deassert_dfll_dvco_reset();
+ else
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
* tegra132_clock_apply_init_table - initialize clocks on Tegra132 SoCs
*
* Program an initial clock rate and enable or disable clocks needed
@@ -1498,6 +1578,8 @@ static void __init tegra124_132_clock_init_post(struct device_node *np)
{
tegra_super_clk_gen4_init(clk_base, pmc_base, tegra124_clks,
&pll_x_params);
+ tegra_init_special_resets(1, tegra124_reset_assert,
+ tegra124_reset_deassert);
tegra_add_of_provider(np);
clks[TEGRA124_CLK_EMC] = tegra_clk_register_emc(clk_base, np,