clk: gate: support sandbox

Introduce io_gate_val for sandbox clk gate test usage

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
index a3a1fdd..70b8794 100644
--- a/drivers/clk/clk-gate.c
+++ b/drivers/clk/clk-gate.c
@@ -55,7 +55,11 @@
 		if (set)
 			reg |= BIT(gate->bit_idx);
 	} else {
+#if CONFIG_IS_ENABLED(SANDBOX_CLK_CCF)
+		reg = gate->io_gate_val;
+#else
 		reg = readl(gate->reg);
+#endif
 
 		if (set)
 			reg |= BIT(gate->bit_idx);
@@ -86,7 +90,11 @@
 			dev_get_clk_ptr(clk->dev) : clk);
 	u32 reg;
 
+#if CONFIG_IS_ENABLED(SANDBOX_CLK_CCF)
+	reg = gate->io_gate_val;
+#else
 	reg = readl(gate->reg);
+#endif
 
 	/* if a set bit disables this clk, flip it before masking */
 	if (gate->flags & CLK_GATE_SET_TO_DISABLE)
@@ -128,6 +136,9 @@
 	gate->reg = reg;
 	gate->bit_idx = bit_idx;
 	gate->flags = clk_gate_flags;
+#if CONFIG_IS_ENABLED(SANDBOX_CLK_CCF)
+	gate->io_gate_val = *(u32 *)reg;
+#endif
 
 	clk = &gate->clk;
 
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index b954773..02ff1a3 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -75,6 +75,9 @@
 	void __iomem	*reg;
 	u8		bit_idx;
 	u8		flags;
+#if CONFIG_IS_ENABLED(SANDBOX_CLK_CCF)
+	u32		io_gate_val;
+#endif
 };
 
 #define to_clk_gate(_clk) container_of(_clk, struct clk_gate, clk)