Re: [PATCH v5 06/10] clk: tegra: Workaround for Tegra114 MSENC problem

From: Prashant Gaikwad
Date: Mon Feb 04 2013 - 01:40:10 EST


On Friday 01 February 2013 03:48 PM, Peter De Schrijver wrote:
Workaround a hardware bug in MSENC during clock enable.

Signed-off-by: Peter De Schrijver <pdeschrijver@xxxxxxxxxx>
---
drivers/clk/tegra/clk-periph-gate.c | 9 +++++++++
drivers/clk/tegra/clk.h | 1 +
2 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/drivers/clk/tegra/clk-periph-gate.c b/drivers/clk/tegra/clk-periph-gate.c
index 6dd5332..c9083fb 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(periph) (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 79f5e2a..8756d9f 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -371,6 +371,7 @@ 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)

Comment for this flag, otherwise

Reviewed-by: Prashant Gaikwad <pgaikwad@xxxxxxxxxx>

void tegra_periph_reset(struct tegra_clk_periph_gate *gate, bool assert);
extern const struct clk_ops tegra_clk_periph_gate_ops;


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