[2/4] clk: rockchip: RK3288: add suspend and resume

Commit Message

Chris Zhong Oct. 15, 2014, 8:48 p.m. UTC

From: Chris Zhong <[e-mail]>

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

Signed-off-by: Tony Xie <[e-mail]>
Signed-off-by: Chris Zhong <[e-mail]>
---

 drivers/clk/rockchip/clk-rk3288.c |   61 +++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

Comments

Doug Anderson Oct. 16, 2014, 3:34 a.m. UTC | #1

Chris,

On Wed, Oct 15, 2014 at 1:48 PM,  <[e-mail]> wrote:
> From: Chris Zhong <[e-mail]>
>
> save and restore some clks, which might be changed in suspend.
>
> Signed-off-by: Tony Xie <[e-mail]>
> Signed-off-by: Chris Zhong <[e-mail]>
> ---
>
>  drivers/clk/rockchip/clk-rk3288.c |   61 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 61 insertions(+)

Put this as patch set #1?  It's safe to do this first and the other
patch won't work without it (right?)


> +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] =
> +                               __raw_readl(rk3288_cru_base + reg_id);

As talked about off-list, should probably not be the __raw version
here and elsewhere in this file.

Patch

diff --git a/drivers/clk/rockchip/clk-rk3288.c b/drivers/clk/rockchip/clk-rk3288.c
index b22a2d2..f14cfdc 100644
--- a/drivers/clk/rockchip/clk-rk3288.c
+++ b/drivers/clk/rockchip/clk-rk3288.c
@@ -680,6 +680,66 @@  static struct rockchip_clk_branch rk3288_clk_branches[] __initdata = {
 	GATE(0, "pclk_isp_in", "ext_isp", 0, RK3288_CLKGATE_CON(16), 3, GFLAGS),
 };
 
+#ifdef CONFIG_PM_SLEEP
+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] =
+				__raw_readl(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];
+
+		__raw_writel(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;
@@ -713,5 +773,6 @@  static void __init rk3288_clk_init(struct device_node *np)
 
 	rockchip_register_softrst(np, 9, reg_base + RK3288_SOFTRST_CON(0),
 				  ROCKCHIP_SOFTRST_HIWORD_MASK);
+	rk3288_clk_sleep_init(reg_base);
 }
 CLK_OF_DECLARE(rk3288_cru, "rockchip,rk3288-cru", rk3288_clk_init);