clk: qcom: alpha: Add support for programming the PLL_FSM_LEGACY_MODE bit

This is used on at least SM6375 and its variations.
Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220921001303.56151-1-konrad.dybcio@somainline.org

drivers/clk/qcom/clk-alpha-pll.c

@@ -27,6 +27,7 @@
 # define PLL_VOTE_FSM_RESET	BIT(21)
 # define PLL_UPDATE		BIT(22)
 # define PLL_UPDATE_BYPASS	BIT(23)
+# define PLL_FSM_LEGACY_MODE	BIT(24)
 # define PLL_OFFLINE_ACK	BIT(28)
 # define ALPHA_PLL_ACK_LATCH	BIT(29)
 # define PLL_ACTIVE_FLAG	BIT(30)
@@ -1123,6 +1124,10 @@ void clk_fabia_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
 		regmap_update_bits(regmap, PLL_USER_CTL(pll), mask, val);
 	}
 
+	if (pll->flags & SUPPORTS_FSM_LEGACY_MODE)
+		regmap_update_bits(regmap, PLL_MODE(pll), PLL_FSM_LEGACY_MODE,
+							PLL_FSM_LEGACY_MODE);
+
 	regmap_update_bits(regmap, PLL_MODE(pll), PLL_UPDATE_BYPASS,
 							PLL_UPDATE_BYPASS);
 

drivers/clk/qcom/clk-alpha-pll.h

@@ -72,9 +72,10 @@ struct clk_alpha_pll {
 
 	const struct pll_vco *vco_table;
 	size_t num_vco;
-#define SUPPORTS_OFFLINE_REQ	BIT(0)
-#define SUPPORTS_FSM_MODE	BIT(2)
+#define SUPPORTS_OFFLINE_REQ		BIT(0)
+#define SUPPORTS_FSM_MODE		BIT(2)
 #define SUPPORTS_DYNAMIC_UPDATE	BIT(3)
+#define SUPPORTS_FSM_LEGACY_MODE	BIT(4)
 	u8 flags;
 
 	struct clk_regmap clkr;