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

zyw
2014-10-15T20:48:39Z

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

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

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

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);
--
1.7.9.5