mach-snapdragon: Fix UART clock flow

UART clock enabling flow was wrong.
Changed the flow according to downstream implementation in LK.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>

arch/arm/mach-snapdragon/clock-apq8016.c

@@ -17,7 +17,6 @@
 
 /* GPLL0 clock control registers */
 #define GPLL0_STATUS_ACTIVE BIT(17)
-#define APCS_GPLL_ENA_VOTE_GPLL0 BIT(0)
 
 static const struct bcr_regs sdc_regs[] = {
 	{
@@ -36,11 +35,17 @@ static const struct bcr_regs sdc_regs[] = {
 	}
 };
 
-static struct gpll0_ctrl gpll0_ctrl = {
+static struct pll_vote_clk gpll0_vote_clk = {
 	.status = GPLL0_STATUS,
 	.status_bit = GPLL0_STATUS_ACTIVE,
 	.ena_vote = APCS_GPLL_ENA_VOTE,
-	.vote_bit = APCS_GPLL_ENA_VOTE_GPLL0,
+	.vote_bit = BIT(0),
+};
+
+static struct vote_clk gcc_blsp1_ahb_clk = {
+	.cbcr_reg = BLSP1_AHB_CBCR,
+	.ena_vote = APCS_CLOCK_BRANCH_ENA_VOTE,
+	.vote_bit = BIT(10),
 };
 
 /* SDHCI */
@@ -55,7 +60,7 @@ static int clk_init_sdc(struct msm_clk_priv *priv, int slot, uint rate)
 	/* 800Mhz/div, gpll0 */
 	clk_rcg_set_rate_mnd(priv->base, &sdc_regs[slot], div, 0, 0,
 			     CFG_CLK_SRC_GPLL0);
-	clk_enable_gpll0(priv->base, &gpll0_ctrl);
+	clk_enable_gpll0(priv->base, &gpll0_vote_clk);
 	clk_enable_cbc(priv->base + SDCC_APPS_CBCR(slot));
 
 	return rate;
@@ -72,12 +77,16 @@ static const struct bcr_regs uart2_regs = {
 /* UART: 115200 */
 static int clk_init_uart(struct msm_clk_priv *priv)
 {
-	/* Enable iface clk */
-	clk_enable_cbc(priv->base + BLSP1_AHB_CBCR);
+	/* Enable AHB clock */
+	clk_enable_vote_clk(priv->base, &gcc_blsp1_ahb_clk);
+
 	/* 7372800 uart block clock @ GPLL0 */
 	clk_rcg_set_rate_mnd(priv->base, &uart2_regs, 1, 144, 15625,
 			     CFG_CLK_SRC_GPLL0);
-	clk_enable_gpll0(priv->base, &gpll0_ctrl);
+
+	/* Vote for gpll0 clock */
+	clk_enable_gpll0(priv->base, &gpll0_vote_clk);
+
 	/* Enable core clk */
 	clk_enable_cbc(priv->base + BLSP1_UART2_APPS_CBCR);
 

arch/arm/mach-snapdragon/clock-apq8096.c

@@ -27,7 +27,7 @@ static const struct bcr_regs sdc_regs = {
 	.D = SDCC2_D,
 };
 
-static const struct gpll0_ctrl gpll0_ctrl = {
+static const struct pll_vote_clk gpll0_vote_clk = {
 	.status = GPLL0_STATUS,
 	.status_bit = GPLL0_STATUS_ACTIVE,
 	.ena_vote = APCS_GPLL_ENA_VOTE,
@@ -41,7 +41,7 @@ static int clk_init_sdc(struct msm_clk_priv *priv, uint rate)
 	clk_enable_cbc(priv->base + SDCC2_AHB_CBCR);
 	clk_rcg_set_rate_mnd(priv->base, &sdc_regs, div, 0, 0,
 			     CFG_CLK_SRC_GPLL0);
-	clk_enable_gpll0(priv->base, &gpll0_ctrl);
+	clk_enable_gpll0(priv->base, &gpll0_vote_clk);
 	clk_enable_cbc(priv->base + SDCC2_APPS_CBCR);
 
 	return rate;

arch/arm/mach-snapdragon/clock-snapdragon.c

@@ -30,7 +30,7 @@ void clk_enable_cbc(phys_addr_t cbcr)
 		;
 }
 
-void clk_enable_gpll0(phys_addr_t base, const struct gpll0_ctrl *gpll0)
+void clk_enable_gpll0(phys_addr_t base, const struct pll_vote_clk *gpll0)
 {
 	if (readl(base + gpll0->status) & gpll0->status_bit)
 		return; /* clock already enabled */
@@ -41,6 +41,21 @@ void clk_enable_gpll0(phys_addr_t base, const struct gpll0_ctrl *gpll0)
 		;
 }
 
+#define BRANCH_ON_VAL (0)
+#define BRANCH_NOC_FSM_ON_VAL BIT(29)
+#define BRANCH_CHECK_MASK GENMASK(31, 28)
+
+void clk_enable_vote_clk(phys_addr_t base, const struct vote_clk *vclk)
+{
+	u32 val;
+
+	setbits_le32(base + vclk->ena_vote, vclk->vote_bit);
+	do {
+		val = readl(base + vclk->cbcr_reg);
+		val &= BRANCH_CHECK_MASK;
+	} while ((val != BRANCH_ON_VAL) && (val != BRANCH_NOC_FSM_ON_VAL));
+}
+
 #define APPS_CMD_RGCR_UPDATE BIT(0)
 
 /* Update clock command via CMD_RGCR */

arch/arm/mach-snapdragon/clock-snapdragon.h

@@ -11,13 +11,18 @@
 #define CFG_CLK_SRC_GPLL0 (1 << 8)
 #define CFG_CLK_SRC_MASK  (7 << 8)
 
-struct gpll0_ctrl {
+struct pll_vote_clk {
 	uintptr_t status;
 	int status_bit;
 	uintptr_t ena_vote;
 	int vote_bit;
 };
 
+struct vote_clk {
+	uintptr_t cbcr_reg;
+	uintptr_t ena_vote;
+	int vote_bit;
+};
 struct bcr_regs {
 	uintptr_t cfg_rcgr;
 	uintptr_t cmd_rcgr;
@@ -30,9 +35,10 @@ struct msm_clk_priv {
 	phys_addr_t base;
 };
 
-void clk_enable_gpll0(phys_addr_t base, const struct gpll0_ctrl *pll0);
+void clk_enable_gpll0(phys_addr_t base, const struct pll_vote_clk *gpll0);
 void clk_bcr_update(phys_addr_t apps_cmd_rgcr);
 void clk_enable_cbc(phys_addr_t cbcr);
+void clk_enable_vote_clk(phys_addr_t base, const struct vote_clk *vclk);
 void clk_rcg_set_rate_mnd(phys_addr_t base, const struct bcr_regs *regs,
 			  int div, int m, int n, int source);
 

arch/arm/mach-snapdragon/include/mach/sysmap-apq8016.h

@@ -13,6 +13,7 @@
 /* Clocks: (from CLK_CTL_BASE)  */
 #define GPLL0_STATUS			(0x2101C)
 #define APCS_GPLL_ENA_VOTE		(0x45000)
+#define APCS_CLOCK_BRANCH_ENA_VOTE (0x45004)
 
 #define SDCC_BCR(n)			((n * 0x1000) + 0x41000)
 #define SDCC_CMD_RCGR(n)		((n * 0x1000) + 0x41004)