ARM: i.MX8M: Add and use function for early UART clock setup

The i.MX8M boards all have the same code for setting up the UART clock.
Add a common helper for it. In the helper just setup the clocks for all
UARTs as it's not worth it to have separate functions for each UART.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

5 files changed, 30 insertions, 24 deletions

diff --git a/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c b/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c
index ac97023631..ebf6203f3a 100644
--- a/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c
+++ b/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c
@@ -25,14 +25,7 @@ extern char __dtb_imx8mq_evk_start[];
 
 static void setup_uart(void)
 {
-	void __iomem *ccm   = IOMEM(MX8MQ_CCM_BASE_ADDR);
-
-	writel(IMX8M_CCM_CCGR_SETTINGn_NEEDED(0),
-	       ccm + IMX8M_CCM_CCGRn_CLR(IMX8M_CCM_CCGR_UART1));
-	writel(IMX8M_CCM_TARGET_ROOTn_ENABLE | IMX8M_UART1_CLK_ROOT__25M_REF_CLK,
-	       ccm + IMX8M_CCM_TARGET_ROOTn(IMX8M_UART1_CLK_ROOT));
-	writel(IMX8M_CCM_CCGR_SETTINGn_NEEDED(0),
-	       ccm + IMX8M_CCM_CCGRn_SET(IMX8M_CCM_CCGR_UART1));
+	imx8m_early_setup_uart_clock();
 
 	imx8mq_setup_pad(IMX8MQ_PAD_UART1_TXD__UART1_TX | UART_PAD_CTRL);
 
diff --git a/arch/arm/boards/phytec-som-imx8mq/lowlevel.c b/arch/arm/boards/phytec-som-imx8mq/lowlevel.c
index 08287a135f..9a48c1dded 100644
--- a/arch/arm/boards/phytec-som-imx8mq/lowlevel.c
+++ b/arch/arm/boards/phytec-som-imx8mq/lowlevel.c
@@ -28,14 +28,7 @@ extern char __dtb_imx8mq_phytec_phycore_som_start[];
 
 static void setup_uart(void)
 {
-	void __iomem *ccm   = IOMEM(MX8MQ_CCM_BASE_ADDR);
-
-	writel(IMX8M_CCM_CCGR_SETTINGn_NEEDED(0),
-	       ccm + IMX8M_CCM_CCGRn_CLR(IMX8M_CCM_CCGR_UART1));
-	writel(IMX8M_CCM_TARGET_ROOTn_ENABLE | IMX8M_UART1_CLK_ROOT__25M_REF_CLK,
-	       ccm + IMX8M_CCM_TARGET_ROOTn(IMX8M_UART1_CLK_ROOT));
-	writel(IMX8M_CCM_CCGR_SETTINGn_NEEDED(0),
-	       ccm + IMX8M_CCM_CCGRn_SET(IMX8M_CCM_CCGR_UART1));
+	imx8m_early_setup_uart_clock();
 
 	imx8mq_setup_pad(IMX8MQ_PAD_UART1_TXD__UART1_TX | UART_PAD_CTRL);
 
diff --git a/arch/arm/boards/zii-imx8mq-dev/lowlevel.c b/arch/arm/boards/zii-imx8mq-dev/lowlevel.c
index bc966589c3..c1ec827184 100644
--- a/arch/arm/boards/zii-imx8mq-dev/lowlevel.c
+++ b/arch/arm/boards/zii-imx8mq-dev/lowlevel.c
@@ -27,14 +27,7 @@
 
 static void setup_uart(void)
 {
-	void __iomem *ccm   = IOMEM(MX8MQ_CCM_BASE_ADDR);
-
-	writel(IMX8M_CCM_CCGR_SETTINGn_NEEDED(0),
-	       ccm + IMX8M_CCM_CCGRn_CLR(IMX8M_CCM_CCGR_UART1));
-	writel(IMX8M_CCM_TARGET_ROOTn_ENABLE | IMX8M_UART1_CLK_ROOT__25M_REF_CLK,
-	       ccm + IMX8M_CCM_TARGET_ROOTn(IMX8M_UART1_CLK_ROOT));
-	writel(IMX8M_CCM_CCGR_SETTINGn_NEEDED(0),
-	       ccm + IMX8M_CCM_CCGRn_SET(IMX8M_CCM_CCGR_UART1));
+	imx8m_early_setup_uart_clock();
 
 	imx8mq_setup_pad(IMX8MQ_PAD_UART1_TXD__UART1_TX | UART_PAD_CTRL);
 
diff --git a/arch/arm/mach-imx/imx8m.c b/arch/arm/mach-imx/imx8m.c
index 596c4140b3..d044531520 100644
--- a/arch/arm/mach-imx/imx8m.c
+++ b/arch/arm/mach-imx/imx8m.c
@@ -133,3 +133,29 @@ static int imx8mq_report_hdmi_firmware(void)
 	return 0;
 }
 console_initcall(imx8mq_report_hdmi_firmware);
+
+void imx8m_early_setup_uart_clock(void)
+{
+	imx8m_ccgr_clock_disable(IMX8M_CCM_CCGR_UART1);
+	imx8m_ccgr_clock_disable(IMX8M_CCM_CCGR_UART2);
+	imx8m_ccgr_clock_disable(IMX8M_CCM_CCGR_UART3);
+	imx8m_ccgr_clock_disable(IMX8M_CCM_CCGR_UART4);
+
+        imx8m_clock_set_target_val(IMX8M_UART1_CLK_ROOT,
+				   IMX8M_CCM_TARGET_ROOTn_ENABLE |
+				   IMX8M_UART1_CLK_ROOT__25M_REF_CLK);
+        imx8m_clock_set_target_val(IMX8M_UART2_CLK_ROOT,
+				   IMX8M_CCM_TARGET_ROOTn_ENABLE |
+				   IMX8M_UART1_CLK_ROOT__25M_REF_CLK);
+        imx8m_clock_set_target_val(IMX8M_UART3_CLK_ROOT,
+				   IMX8M_CCM_TARGET_ROOTn_ENABLE |
+				   IMX8M_UART1_CLK_ROOT__25M_REF_CLK);
+        imx8m_clock_set_target_val(IMX8M_UART4_CLK_ROOT,
+				   IMX8M_CCM_TARGET_ROOTn_ENABLE |
+				   IMX8M_UART1_CLK_ROOT__25M_REF_CLK);
+
+	imx8m_ccgr_clock_enable(IMX8M_CCM_CCGR_UART1);
+	imx8m_ccgr_clock_enable(IMX8M_CCM_CCGR_UART2);
+	imx8m_ccgr_clock_enable(IMX8M_CCM_CCGR_UART3);
+	imx8m_ccgr_clock_enable(IMX8M_CCM_CCGR_UART4);
+}
diff --git a/arch/arm/mach-imx/include/mach/imx8m-ccm-regs.h b/arch/arm/mach-imx/include/mach/imx8m-ccm-regs.h
index ff207b80f9..70a7e4af9d 100644
--- a/arch/arm/mach-imx/include/mach/imx8m-ccm-regs.h
+++ b/arch/arm/mach-imx/include/mach/imx8m-ccm-regs.h
@@ -48,6 +48,7 @@
 #define IMX8M_CCM_CCGR_SETTINGn_NEEDED_RUN_WAIT(n)	IMX8M_CCM_CCGR_SETTINGn(n, 0b10)
 #define IMX8M_CCM_CCGR_SETTINGn_NEEDED(n)		IMX8M_CCM_CCGR_SETTINGn(n, 0b11)
 
+void imx8m_early_setup_uart_clock(void);
 void imx8m_clock_set_target_val(int clock_id, u32 val);
 void imx8m_ccgr_clock_enable(int index);
 void imx8m_ccgr_clock_disable(int index);