[PATCH V1 05/12] clk: tegra: add support for OSC clock resume

From: Sowjanya Komatineni
Date: Tue May 21 2019 - 19:34:07 EST


This patch adds support for restoring OSC control context on resume.

Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
---
drivers/clk/tegra/clk-tegra-fixed.c | 15 +++++++++++++++
drivers/clk/tegra/clk.h | 1 +
2 files changed, 16 insertions(+)

diff --git a/drivers/clk/tegra/clk-tegra-fixed.c b/drivers/clk/tegra/clk-tegra-fixed.c
index 91c38f1666c1..7efb35717e06 100644
--- a/drivers/clk/tegra/clk-tegra-fixed.c
+++ b/drivers/clk/tegra/clk-tegra-fixed.c
@@ -28,7 +28,10 @@
#define OSC_CTRL 0x50
#define OSC_CTRL_OSC_FREQ_SHIFT 28
#define OSC_CTRL_PLL_REF_DIV_SHIFT 26
+#define OSC_CTRL_MASK (0x3f2 | \
+ (0xf << OSC_CTRL_OSC_FREQ_SHIFT))

+static u32 osc_ctrl_ctx;
int __init tegra_osc_clk_init(void __iomem *clk_base, struct tegra_clk *clks,
unsigned long *input_freqs, unsigned int num,
unsigned int clk_m_div, unsigned long *osc_freq,
@@ -107,3 +110,15 @@ void __init tegra_fixed_clk_init(struct tegra_clk *tegra_clks)
*dt_clk = clk;
}
}
+
+#ifdef CONFIG_PM_SLEEP
+void tegra_clk_osc_resume(void __iomem *clk_base)
+{
+ u32 val;
+
+ val = readl_relaxed(clk_base + OSC_CTRL) & ~OSC_CTRL_MASK;
+ val |= osc_ctrl_ctx;
+ writel_relaxed(val, clk_base + OSC_CTRL);
+ fence_udelay(2, clk_base);
+}
+#endif
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index ef444648fcb1..7567cf7bd29e 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -856,6 +856,7 @@ void tegra_clk_sync_state_pll_out(struct clk *clk);
void tegra_clk_periph_suspend(void __iomem *clk_base);
void tegra_clk_periph_resume(void __iomem *clk_base);
void tegra_clk_periph_force_on(u32 *clks_on, int count, void __iomem *clk_base);
+void tegra_clk_osc_resume(void __iomem *clk_base);
#endif


--
2.7.4