MLK-21052-08 clk: imx: Add CLK_SET_PARENT_NOCACHE

Implement a CLK_SET_PARENT_NOCACHE flag in clk core for imx8 clk
implementation where the parent needs to be restore after PM domain is
up.

Reviewed-by: Anson Huang <anson.huang@nxp.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Ranjani Vaidyanathan <Ranjani.Vaidyanathan@nxp.com>
(cherry picked from commit 87e997822c)
[Leonard: split clk core part]
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>

drivers/clk/clk.c

@@ -2465,7 +2465,8 @@ static int clk_core_set_parent_nolock(struct clk_core *core,
 	if (!core)
 		return 0;
 
-	if (core->parent == parent)
+	if ((core->parent == parent) &&
+		!(core->flags & CLK_SET_PARENT_NOCACHE))
 		return 0;
 
 	/* verify ops for multi-parent clks */

include/linux/clk-provider.h

@@ -32,6 +32,7 @@
 #define CLK_OPS_PARENT_ENABLE	BIT(12)
 /* duty cycle call may be forwarded to the parent clock */
 #define CLK_DUTY_CYCLE_PARENT	BIT(13)
+#define CLK_SET_PARENT_NOCACHE	BIT(14) /* do not use the cached clk parent */
 
 struct clk;
 struct clk_hw;