ARM: tegra: introduce tegra_cpu_car_ops structures

The tegra_cpu_car_ops provide the interface for CPU to control
it's clock gating and reset status. The other drivers should use
this for CPU control. And should not directly access CAR registers
to control CPU.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 72 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/tegra30_clocks.c b/arch/arm/mach-tegra/tegra30_clocks.c
index 63615dadfbb2..5cd502c27163 100644
--- a/arch/arm/mach-tegra/tegra30_clocks.c
+++ b/arch/arm/mach-tegra/tegra30_clocks.c
@@ -35,6 +35,7 @@
 
 #include "clock.h"
 #include "fuse.h"
+#include "tegra_cpu_car.h"
 
 #define USE_PLL_LOCK_BITS 0
 
@@ -299,6 +300,16 @@
 /* FIXME: recommended safety delay after lock is detected */
 #define PLL_POST_LOCK_DELAY		100
 
+/* Tegra CPU clock and reset control regs */
+#define TEGRA_CLK_RST_CONTROLLER_CLK_CPU_CMPLX		0x4c
+#define TEGRA_CLK_RST_CONTROLLER_RST_CPU_CMPLX_SET	0x340
+#define TEGRA_CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR	0x344
+#define TEGRA30_CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR	0x34c
+#define TEGRA30_CLK_RST_CONTROLLER_CPU_CMPLX_STATUS	0x470
+
+#define CPU_CLOCK(cpu)	(0x1 << (8 + cpu))
+#define CPU_RESET(cpu)	(0x1111ul << (cpu))
+
 /**
 * Structure defining the fields for USB UTMI clocks Parameters.
 */
@@ -2221,3 +2232,64 @@ struct clk_ops tegra_cml_clk_ops = {
 struct clk_ops tegra_pciex_clk_ops = {
 	.recalc_rate = tegra30_clk_fixed_recalc_rate,
 };
+
+/* Tegra30 CPU clock and reset control functions */
+static void tegra30_wait_cpu_in_reset(u32 cpu)
+{
+	unsigned int reg;
+
+	do {
+		reg = readl(reg_clk_base +
+			    TEGRA30_CLK_RST_CONTROLLER_CPU_CMPLX_STATUS);
+		cpu_relax();
+	} while (!(reg & (1 << cpu)));	/* check CPU been reset or not */
+
+	return;
+}
+
+static void tegra30_put_cpu_in_reset(u32 cpu)
+{
+	writel(CPU_RESET(cpu),
+	       reg_clk_base + TEGRA_CLK_RST_CONTROLLER_RST_CPU_CMPLX_SET);
+	dmb();
+}
+
+static void tegra30_cpu_out_of_reset(u32 cpu)
+{
+	writel(CPU_RESET(cpu),
+	       reg_clk_base + TEGRA_CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR);
+	wmb();
+}
+
+static void tegra30_enable_cpu_clock(u32 cpu)
+{
+	unsigned int reg;
+
+	writel(CPU_CLOCK(cpu),
+	       reg_clk_base + TEGRA30_CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR);
+	reg = readl(reg_clk_base +
+		    TEGRA30_CLK_RST_CONTROLLER_CLK_CPU_CMPLX_CLR);
+}
+
+static void tegra30_disable_cpu_clock(u32 cpu)
+{
+
+	unsigned int reg;
+
+	reg = readl(reg_clk_base + TEGRA_CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
+	writel(reg | CPU_CLOCK(cpu),
+	       reg_clk_base + TEGRA_CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
+}
+
+static struct tegra_cpu_car_ops tegra30_cpu_car_ops = {
+	.wait_for_reset	= tegra30_wait_cpu_in_reset,
+	.put_in_reset	= tegra30_put_cpu_in_reset,
+	.out_of_reset	= tegra30_cpu_out_of_reset,
+	.enable_clock	= tegra30_enable_cpu_clock,
+	.disable_clock	= tegra30_disable_cpu_clock,
+};
+
+void __init tegra30_cpu_car_ops_init(void)
+{
+	tegra_cpu_car_ops = &tegra30_cpu_car_ops;
+}