4 files changed, 39 insertions, 1 deletions

diff --git a/drivers/clk/tegra/clk-super.c b/drivers/clk/tegra/clk-super.c
index 39ef31b46df5..e2a1e95a8db7 100644
--- a/drivers/clk/tegra/clk-super.c
+++ b/drivers/clk/tegra/clk-super.c
@@ -28,6 +28,9 @@
 #define super_state_to_src_shift(m, s) ((m->width * s))
 #define super_state_to_src_mask(m) (((1 << m->width) - 1))
 
+#define CCLK_SRC_PLLP_OUT0 4
+#define CCLK_SRC_PLLP_OUT4 5
+
 static u8 clk_super_get_parent(struct clk_hw *hw)
 {
 	struct tegra_clk_super_mux *mux = to_clk_super_mux(hw);
@@ -97,12 +100,23 @@ static int clk_super_set_parent(struct clk_hw *hw, u8 index)
 		if (index == mux->div2_index)
 			index = mux->pllx_index;
 	}
+
+	/* enable PLLP branches to CPU before selecting PLLP source */
+	if ((mux->flags & TEGRA210_CPU_CLK) &&
+	    (index == CCLK_SRC_PLLP_OUT0 || index == CCLK_SRC_PLLP_OUT4))
+		tegra_clk_set_pllp_out_cpu(true);
+
 	val &= ~((super_state_to_src_mask(mux)) << shift);
 	val |= (index & (super_state_to_src_mask(mux))) << shift;
 
 	writel_relaxed(val, mux->reg);
 	udelay(2);
 
+	/* disable PLLP branches to CPU if not used */
+	if ((mux->flags & TEGRA210_CPU_CLK) &&
+	    index != CCLK_SRC_PLLP_OUT0 && index != CCLK_SRC_PLLP_OUT4)
+		tegra_clk_set_pllp_out_cpu(false);
+
 out:
 	if (mux->lock)
 		spin_unlock_irqrestore(mux->lock, flags);
diff --git a/drivers/clk/tegra/clk-tegra-super-gen4.c b/drivers/clk/tegra/clk-tegra-super-gen4.c
index cdfe7c9697e1..5760c978bef7 100644
--- a/drivers/clk/tegra/clk-tegra-super-gen4.c
+++ b/drivers/clk/tegra/clk-tegra-super-gen4.c
@@ -180,7 +180,7 @@ static void __init tegra_super_clk_init(void __iomem *clk_base,
 					gen_info->num_cclk_g_parents,
 					CLK_SET_RATE_PARENT,
 					clk_base + CCLKG_BURST_POLICY,
-					0, 4, 8, 0, NULL);
+					TEGRA210_CPU_CLK, 4, 8, 0, NULL);
 		} else {
 			clk = tegra_clk_register_super_mux("cclk_g",
 					gen_info->cclk_g_parents,
@@ -196,6 +196,11 @@ static void __init tegra_super_clk_init(void __iomem *clk_base,
 	dt_clk = tegra_lookup_dt_id(tegra_clk_cclk_lp, tegra_clks);
 	if (dt_clk) {
 		if (gen_info->gen == gen5) {
+			/*
+			 * TEGRA210_CPU_CLK flag is not needed for cclk_lp as
+			 * cluster switching is not currently supported on
+			 * Tegra210 and also cpu_lp is not used.
+			 */
 			clk = tegra_clk_register_super_mux("cclk_lp",
 					gen_info->cclk_lp_parents,
 					gen_info->num_cclk_lp_parents,
diff --git a/drivers/clk/tegra/clk.c b/drivers/clk/tegra/clk.c
index 573e3c967ae1..eb08047fd02f 100644
--- a/drivers/clk/tegra/clk.c
+++ b/drivers/clk/tegra/clk.c
@@ -23,6 +23,7 @@
 #define CLK_OUT_ENB_W			0x364
 #define CLK_OUT_ENB_X			0x280
 #define CLK_OUT_ENB_Y			0x298
+#define CLK_ENB_PLLP_OUT_CPU		BIT(31)
 #define CLK_OUT_ENB_SET_L		0x320
 #define CLK_OUT_ENB_CLR_L		0x324
 #define CLK_OUT_ENB_SET_H		0x328
@@ -199,6 +200,19 @@ const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
 	}
 }
 
+void tegra_clk_set_pllp_out_cpu(bool enable)
+{
+	u32 val;
+
+	val = readl_relaxed(clk_base + CLK_OUT_ENB_Y);
+	if (enable)
+		val |= CLK_ENB_PLLP_OUT_CPU;
+	else
+		val &= ~CLK_ENB_PLLP_OUT_CPU;
+
+	writel_relaxed(val, clk_base + CLK_OUT_ENB_Y);
+}
+
 struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
 {
 	clk_base = regs;
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index 7c956ce521d6..21bb0f24c6c1 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -669,6 +669,9 @@ struct clk *tegra_clk_register_periph_data(void __iomem *clk_base,
  * Flags:
  * TEGRA_DIVIDER_2 - LP cluster has additional divider. This flag indicates
  *     that this is LP cluster clock.
+ * TEGRA210_CPU_CLK - This flag is used to identify CPU cluster for gen5
+ * super mux parent using PLLP branches. To use PLLP branches to CPU, need
+ * to configure additional bit PLLP_OUT_CPU in the clock registers.
  */
 struct tegra_clk_super_mux {
 	struct clk_hw	hw;
@@ -685,6 +688,7 @@ struct tegra_clk_super_mux {
 #define to_clk_super_mux(_hw) container_of(_hw, struct tegra_clk_super_mux, hw)
 
 #define TEGRA_DIVIDER_2 BIT(0)
+#define TEGRA210_CPU_CLK BIT(1)
 
 extern const struct clk_ops tegra_clk_super_ops;
 struct clk *tegra_clk_register_super_mux(const char *name,
@@ -830,6 +834,7 @@ int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div);
 int div_frac_get(unsigned long rate, unsigned parent_rate, u8 width,
 		 u8 frac_width, u8 flags);
 void tegra_clk_osc_resume(void __iomem *clk_base);
+void tegra_clk_set_pllp_out_cpu(bool enable);
 
 
 /* Combined read fence with delay */