rockchip: px30: support debug uart on UART0

UART0 can obviously also be used for debug uart in U-Boot, so let's add
its support.

Cc: Quentin Schulz <foss+uboot@0leil.net>
Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/include/asm/arch-rockchip/cru_px30.h b/arch/arm/include/asm/arch-rockchip/cru_px30.h
index 732ca37..b66277f 100644
--- a/arch/arm/include/asm/arch-rockchip/cru_px30.h
+++ b/arch/arm/include/asm/arch-rockchip/cru_px30.h
@@ -445,5 +445,24 @@
 	/* CRU_PMU_CLK_SEL0_CON */
 	CLK_PMU_PCLK_DIV_SHIFT		= 0,
 	CLK_PMU_PCLK_DIV_MASK		= 0x1f << CLK_PMU_PCLK_DIV_SHIFT,
+
+	/* CRU_PMU_CLKSEL3_CON */
+	UART0_PLL_SEL_SHIFT		= 14,
+	UART0_PLL_SEL_MASK		= 3 << UART0_PLL_SEL_SHIFT,
+	UART0_PLL_SEL_GPLL		= 0,
+	UART0_PLL_SEL_24M,
+	UART0_PLL_SEL_480M,
+	UART0_PLL_SEL_NPLL,
+	UART0_DIV_CON_SHIFT		= 0,
+	UART0_DIV_CON_MASK		= 0x1f << UART0_DIV_CON_SHIFT,
+
+	/* CRU_PMU_CLKSEL4_CON */
+	UART0_CLK_SEL_SHIFT		= 14,
+	UART0_CLK_SEL_MASK		= 3 << UART0_PLL_SEL_SHIFT,
+	UART0_CLK_SEL_UART0		= 0,
+	UART0_CLK_SEL_UART0_NP5,
+	UART0_CLK_SEL_UART0_FRAC,
+	UART0_DIVNP5_SHIFT		= 0,
+	UART0_DIVNP5_MASK		= 0x1f << UART0_DIVNP5_SHIFT,
 };
 #endif
diff --git a/arch/arm/mach-rockchip/px30/px30.c b/arch/arm/mach-rockchip/px30/px30.c
index be70d30..0641e6a 100644
--- a/arch/arm/mach-rockchip/px30/px30.c
+++ b/arch/arm/mach-rockchip/px30/px30.c
@@ -41,6 +41,7 @@
 #define PMUGRF_BASE			0xff010000
 #define GRF_BASE			0xff140000
 #define CRU_BASE			0xff2b0000
+#define PMUCRU_BASE			0xff2bc000
 #define VIDEO_PHY_BASE			0xff2e0000
 #define SERVICE_CORE_ADDR		0xff508000
 #define DDR_FW_BASE			0xff534000
@@ -198,6 +199,21 @@
 	GPIO3A1_UART5_RX	= 4,
 };
 
+/* PMUGRF_GPIO0BL_IOMUX */
+enum {
+	GPIO0B3_SHIFT		= 6,
+	GPIO0B3_MASK		= 0x3 << GPIO0B3_SHIFT,
+	GPIO0B3_GPIO		= 0,
+	GPIO0B3_UART0_RX,
+	GPIO0B3_PMU_DEBUG1,
+
+	GPIO0B2_SHIFT		= 4,
+	GPIO0B2_MASK		= 0x3 << GPIO0B2_SHIFT,
+	GPIO0B2_GPIO		= 0,
+	GPIO0B2_UART0_TX,
+	GPIO0B2_PMU_DEBUG0,
+};
+
 /* PMUGRF_GPIO0CL_IOMUX */
 enum {
 	GPIO0C1_SHIFT		= 2,
@@ -276,12 +292,16 @@
 void board_debug_uart_init(void)
 {
 #if defined(CONFIG_DEBUG_UART_BASE) && \
-	(CONFIG_DEBUG_UART_BASE == 0xff168000) && \
-	(CONFIG_DEBUG_UART_CHANNEL != 1)
+	(((CONFIG_DEBUG_UART_BASE == 0xff168000) && \
+	(CONFIG_DEBUG_UART_CHANNEL != 1)) || \
+	CONFIG_DEBUG_UART_BASE == 0xff030000)
 	static struct px30_pmugrf * const pmugrf = (void *)PMUGRF_BASE;
 #endif
 	static struct px30_grf * const grf = (void *)GRF_BASE;
 	static struct px30_cru * const cru = (void *)CRU_BASE;
+#if defined(CONFIG_DEBUG_UART_BASE) && CONFIG_DEBUG_UART_BASE == 0xff030000
+	static struct px30_pmucru * const pmucru = (void *)PMUCRU_BASE;
+#endif
 
 #if defined(CONFIG_DEBUG_UART_BASE) && (CONFIG_DEBUG_UART_BASE == 0xff158000)
 	/* uart_sel_clk default select 24MHz */
@@ -346,6 +366,19 @@
 		     GPIO3A2_MASK | GPIO3A1_MASK,
 		     GPIO3A2_UART5_TX << GPIO3A2_SHIFT |
 		     GPIO3A1_UART5_RX << GPIO3A1_SHIFT);
+#elif defined(CONFIG_DEBUG_UART_BASE) && (CONFIG_DEBUG_UART_BASE == 0xff030000)
+	/* uart_sel_clk default select 24MHz */
+	rk_clrsetreg(&pmucru->pmu_clksel_con[3],
+		     UART0_PLL_SEL_MASK | UART0_DIV_CON_MASK,
+		     UART0_PLL_SEL_24M << UART0_PLL_SEL_SHIFT | 0);
+	rk_clrsetreg(&pmucru->pmu_clksel_con[4],
+		     UART0_CLK_SEL_MASK,
+		     UART0_CLK_SEL_UART0 << UART0_CLK_SEL_SHIFT);
+
+	rk_clrsetreg(&pmugrf->gpio0bl_iomux,
+		     GPIO0B3_MASK | GPIO0B2_MASK,
+		     GPIO0B3_UART0_RX << GPIO0B3_SHIFT |
+		     GPIO0B2_UART0_TX << GPIO0B2_SHIFT);
 #else
 	/* GRF_IOFUNC_CON0 */
 	enum {