[PATCH v4 4/5] clk: rockchip: add pll up and down when change pll freq

[Elaine Zhang <zhangqing@rock-chips.com>]

set pll sequence:
	->set pll to slow mode or other plls
	->set pll down
	->set pll params
	->set pll up
	->wait pll lock status
	->set pll to normal mode

To slove the system error:
wait_pll_lock: timeout waiting for pll to lock
pll_set_params: pll update unsucessful,
		trying to restore old params

Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
---
 drivers/clk/rockchip/clk-pll.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/clk/rockchip/clk-pll.c b/drivers/clk/rockchip/clk-pll.c
index 198417d56300..390e9473807a 100644
--- a/drivers/clk/rockchip/clk-pll.c
+++ b/drivers/clk/rockchip/clk-pll.c
@@ -199,6 +199,11 @@ static int rockchip_rk3036_pll_set_params(struct rockchip_clk_pll *pll,
 		rate_change_remuxed = 1;
 	}
 
+	/* set pll power down */
+	writel(HIWORD_UPDATE(RK3036_PLLCON1_PWRDOWN,
+			     RK3036_PLLCON1_PWRDOWN, 0),
+	       pll->reg_base + RK3036_PLLCON(1));
+
 	/* update pll values */
 	writel_relaxed(HIWORD_UPDATE(rate->fbdiv, RK3036_PLLCON0_FBDIV_MASK,
 					  RK3036_PLLCON0_FBDIV_SHIFT) |
@@ -220,6 +225,11 @@ static int rockchip_rk3036_pll_set_params(struct rockchip_clk_pll *pll,
 	pllcon |= rate->frac << RK3036_PLLCON2_FRAC_SHIFT;
 	writel_relaxed(pllcon, pll->reg_base + RK3036_PLLCON(2));
 
+	/* set pll power up */
+	writel(HIWORD_UPDATE(0, RK3036_PLLCON1_PWRDOWN, 0),
+	       pll->reg_base + RK3036_PLLCON(1));
+	udelay(1);
+
 	/* wait for the pll to lock */
 	ret = rockchip_pll_wait_lock(pll);
 	if (ret) {
@@ -676,6 +686,11 @@ static int rockchip_rk3399_pll_set_params(struct rockchip_clk_pll *pll,
 		rate_change_remuxed = 1;
 	}
 
+	/* set pll power down */
+	writel(HIWORD_UPDATE(RK3399_PLLCON3_PWRDOWN,
+			     RK3399_PLLCON3_PWRDOWN, 0),
+	       pll->reg_base + RK3399_PLLCON(3));
+
 	/* update pll values */
 	writel_relaxed(HIWORD_UPDATE(rate->fbdiv, RK3399_PLLCON0_FBDIV_MASK,
 						  RK3399_PLLCON0_FBDIV_SHIFT),
@@ -699,6 +714,12 @@ static int rockchip_rk3399_pll_set_params(struct rockchip_clk_pll *pll,
 					    RK3399_PLLCON3_DSMPD_SHIFT),
 		       pll->reg_base + RK3399_PLLCON(3));
 
+	/* set pll power up */
+	writel(HIWORD_UPDATE(0,
+			     RK3399_PLLCON3_PWRDOWN, 0),
+	       pll->reg_base + RK3399_PLLCON(3));
+	udelay(1);
+
 	/* wait for the pll to lock */
 	ret = rockchip_rk3399_pll_wait_lock(pll);
 	if (ret) {
-- 
2.17.1