clk: tegra: Workaround for Tegra114 MSENC problem

Workaround a hardware bug in MSENC during clock enable.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

2 files changed, 11 insertions, 0 deletions

diff --git a/drivers/clk/tegra/clk-periph-gate.c b/drivers/clk/tegra/clk-periph-gate.c
index d87e1cece9fa..bafee9895a24 100644
--- a/drivers/clk/tegra/clk-periph-gate.c
+++ b/drivers/clk/tegra/clk-periph-gate.c
@@ -43,6 +43,8 @@ static DEFINE_SPINLOCK(periph_ref_lock);
 
 #define periph_clk_to_bit(gate) (1 << (gate->clk_num % 32))
 
+#define LVL2_CLK_GATE_OVRE 0x554
+
 /* Peripheral gate clock ops */
 static int clk_periph_is_enabled(struct clk_hw *hw)
 {
@@ -83,6 +85,13 @@ static int clk_periph_enable(struct clk_hw *hw)
                 }
         }
 
+        if (gate->flags & TEGRA_PERIPH_WAR_1005168) {
+                writel_relaxed(0, gate->clk_base + LVL2_CLK_GATE_OVRE);
+                writel_relaxed(BIT(22), gate->clk_base + LVL2_CLK_GATE_OVRE);
+                udelay(1);
+                writel_relaxed(0, gate->clk_base + LVL2_CLK_GATE_OVRE);
+        }
+
         spin_unlock_irqrestore(&periph_ref_lock, flags);
 
         return 0;
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index fd12b77c985d..fb48f0467b9d 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -358,6 +358,7 @@ struct tegra_clk_periph_regs {
  * TEGRA_PERIPH_ON_APB - If peripheral is in the APB bus then read the
  *     bus to flush the write operation in apb bus. This flag indicates
  *     that this peripheral is in apb bus.
+ * TEGRA_PERIPH_WAR_1005168 - Apply workaround for Tegra114 MSENC bug
  */
 struct tegra_clk_periph_gate {
         u32                     magic;
@@ -377,6 +378,7 @@ struct tegra_clk_periph_gate {
 #define TEGRA_PERIPH_NO_RESET BIT(0)
 #define TEGRA_PERIPH_MANUAL_RESET BIT(1)
 #define TEGRA_PERIPH_ON_APB BIT(2)
+#define TEGRA_PERIPH_WAR_1005168 BIT(3)
 
 void tegra_periph_reset(struct tegra_clk_periph_gate *gate, bool assert);
 extern const struct clk_ops tegra_clk_periph_gate_ops;