save and restore some clks, which might be changed in suspend.

Signed-off-by: Tony Xie <x...@rock-chips.com>
Signed-off-by: Chris Zhong <z...@rock-chips.com>

---

Changes in v4: None
Changes in v3: None
Changes in v2:
- __raw_readl/__raw_writel replaced by readl_relaxed/writel_relaxed

 drivers/clk/rockchip/clk-rk3288.c |   63 +++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/drivers/clk/rockchip/clk-rk3288.c 
b/drivers/clk/rockchip/clk-rk3288.c
index 2327829..0731b18 100644
--- a/drivers/clk/rockchip/clk-rk3288.c
+++ b/drivers/clk/rockchip/clk-rk3288.c
@@ -16,6 +16,7 @@
 #include <linux/clk-provider.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/syscore_ops.h>
 #include <dt-bindings/clock/rk3288-cru.h>
 #include "clk.h"
 
@@ -762,6 +763,67 @@ static const char *rk3288_critical_clocks[] __initconst = {
        "hclk_peri",
 };
 
+#ifdef CONFIG_PM_SLEEP
+static void __iomem *rk3288_cru_base;
+static const int rk3288_saved_cru_reg_ids[] = {
+       RK3288_MODE_CON,
+       RK3288_CLKSEL_CON(0),
+       RK3288_CLKSEL_CON(1),
+       RK3288_CLKSEL_CON(10),
+       RK3288_CLKSEL_CON(33),
+       RK3288_CLKSEL_CON(37),
+};
+
+static u32 rk3288_saved_cru_regs[ARRAY_SIZE(rk3288_saved_cru_reg_ids)];
+
+/*
+ * cru will be set in maskrom when system wake up from fastboot
+ * mode in suspend,
+ * so the operation is saving the changed regs.
+ * The apll/cpll/gpll will be set into slow mode in maskrom.
+ * It is mean that resume code run in 24m quit slowly!
+ * so we must resume these plls as soon as possible.
+ */
+static int rk3288_clk_suspend(void)
+{
+       int i, reg_id;
+
+       for (i = 0; i < ARRAY_SIZE(rk3288_saved_cru_reg_ids); i++) {
+               reg_id = rk3288_saved_cru_reg_ids[i];
+
+               rk3288_saved_cru_regs[i] =
+                               readl_relaxed(rk3288_cru_base + reg_id);
+       }
+       return 0;
+}
+
+static void rk3288_clk_resume(void)
+{
+       int i, reg_id;
+
+       for (i = ARRAY_SIZE(rk3288_saved_cru_reg_ids) - 1; i >= 0; i--) {
+               reg_id = rk3288_saved_cru_reg_ids[i];
+
+               writel_relaxed(rk3288_saved_cru_regs[i] | 0xffff0000,
+                              rk3288_cru_base + reg_id);
+       }
+}
+
+static struct syscore_ops rk3288_clk_syscore_ops = {
+       .suspend = rk3288_clk_suspend,
+       .resume = rk3288_clk_resume,
+};
+
+static void rk3288_clk_sleep_init(void __iomem *reg_base)
+{
+       rk3288_cru_base = reg_base;
+       register_syscore_ops(&rk3288_clk_syscore_ops);
+}
+
+#else /* CONFIG_PM_SLEEP */
+static void rk3288_clk_sleep_init(void __iomem *reg_base) {}
+#endif
+
 static void __init rk3288_clk_init(struct device_node *np)
 {
        void __iomem *reg_base;
@@ -810,5 +872,6 @@ static void __init rk3288_clk_init(struct device_node *np)
                                  ROCKCHIP_SOFTRST_HIWORD_MASK);
 
        rockchip_register_restart_notifier(RK3288_GLB_SRST_FST);
+       rk3288_clk_sleep_init(reg_base);
 }
 CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to