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-rw-r--r--drivers/clk/tegra/clk-tegra124.c68
-rw-r--r--include/dt-bindings/reset/tegra124-car.h12
2 files changed, 80 insertions, 0 deletions
diff --git a/drivers/clk/tegra/clk-tegra124.c b/drivers/clk/tegra/clk-tegra124.c
index e8cca3eac007..106ec458c945 100644
--- a/drivers/clk/tegra/clk-tegra124.c
+++ b/drivers/clk/tegra/clk-tegra124.c
@@ -24,6 +24,7 @@
#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"
@@ -39,6 +40,9 @@
#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
@@ -1415,6 +1419,68 @@ 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
@@ -1499,6 +1565,8 @@ 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,
diff --git a/include/dt-bindings/reset/tegra124-car.h b/include/dt-bindings/reset/tegra124-car.h
new file mode 100644
index 000000000000..070e4f6e7486
--- /dev/null
+++ b/include/dt-bindings/reset/tegra124-car.h
@@ -0,0 +1,12 @@
+/*
+ * This header provides Tegra124-specific constants for binding
+ * nvidia,tegra124-car.
+ */
+
+#ifndef _DT_BINDINGS_RESET_TEGRA124_CAR_H
+#define _DT_BINDINGS_RESET_TEGRA124_CAR_H
+
+#define TEGRA124_RESET(x) (6 * 32 + (x))
+#define TEGRA124_RST_DFLL_DVCO TEGRA124_RESET(0)
+
+#endif /* _DT_BINDINGS_RESET_TEGRA124_CAR_H */