[PATCH 2/2] ARM: i.MX8M boards: always set up UART

Sascha Hauer s.hauer at pengutronix.de
Fri Aug 21 00:35:35 EDT 2020


Quoting Lucas on b96cc34f91 ("ARM: nxp-imx8mm-evk: always set up UART"):

| When the TF-A is configured to have some output on the UART it does not
| set up the UART on its own, but just expects a pre-existing configuration.
| If Barebox did not set up the UART in the !DEBUG_LL case, TF-A will just
| hang without any user accessible debug output, which is a very non-obvious
| failure, so better be safe and always set up the UART in case TF-A wants
| to use it.

This patch adopts this for all i.MX8M boards and makes the early UART
setup consistent across all of them. We also add pbl_set_putc() to
enable regular PBL console messages. For the i.MX8MM-EVK the unnecessary
call to imx8m_uart_setup_ll() is dropped; we already configured the
UART in imx8m_uart_setup(), no need to do that again.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 arch/arm/boards/nxp-imx8mm-evk/lowlevel.c    | 10 +++++-----
 arch/arm/boards/nxp-imx8mp-evk/lowlevel.c    |  6 +++++-
 arch/arm/boards/nxp-imx8mq-evk/lowlevel.c    |  5 ++++-
 arch/arm/boards/phytec-som-imx8mq/lowlevel.c |  6 +++++-
 arch/arm/boards/zii-imx8mq-dev/lowlevel.c    |  5 ++++-
 5 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/arch/arm/boards/nxp-imx8mm-evk/lowlevel.c b/arch/arm/boards/nxp-imx8mm-evk/lowlevel.c
index 96b78d2c66..2297dc01e7 100644
--- a/arch/arm/boards/nxp-imx8mm-evk/lowlevel.c
+++ b/arch/arm/boards/nxp-imx8mm-evk/lowlevel.c
@@ -28,16 +28,16 @@ extern char __dtb_imx8mm_evk_start[];
 
 static void setup_uart(void)
 {
+	void __iomem *uart = IOMEM(MX8M_UART2_BASE_ADDR);
+
 	imx8m_early_setup_uart_clock();
 
 	imx8mm_setup_pad(IMX8MM_PAD_UART2_TXD_UART2_TX | UART_PAD_CTRL);
+	imx8m_uart_setup(uart);
 
-	imx8m_uart_setup((void *)MX8M_UART2_BASE_ADDR);
+	pbl_set_putc(imx_uart_putc, uart);
 
-	if (IS_ENABLED(CONFIG_DEBUG_LL)) {
-		imx8m_uart_setup_ll();
-		putc_ll('>');
-	}
+	putc_ll('>');
 }
 
 static void pmic_reg_write(void *i2c, int reg, uint8_t val)
diff --git a/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c b/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c
index 5df1ed0780..c193640865 100644
--- a/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c
+++ b/arch/arm/boards/nxp-imx8mp-evk/lowlevel.c
@@ -34,11 +34,15 @@ extern char __dtb_imx8mp_evk_start[];
 
 static void setup_uart(void)
 {
+	void __iomem *uart = IOMEM(MX8M_UART2_BASE_ADDR);
+
 	imx8m_early_setup_uart_clock();
 
 	imx8mp_setup_pad(MX8MP_PAD_UART2_TXD__UART2_DCE_TX | UART_PAD_CTRL);
 	imx8mp_setup_pad(MX8MP_PAD_UART2_RXD__UART2_DCE_RX | UART_PAD_CTRL);
-	imx8m_uart_setup_ll();
+	imx8m_uart_setup(uart);
+
+	pbl_set_putc(imx_uart_putc, uart);
 
 	putc_ll('>');
 }
diff --git a/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c b/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c
index 39358afad1..9d16b7e32a 100644
--- a/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c
+++ b/arch/arm/boards/nxp-imx8mq-evk/lowlevel.c
@@ -26,11 +26,14 @@ extern char __dtb_imx8mq_evk_start[];
 
 static void setup_uart(void)
 {
+	void __iomem *uart = IOMEM(MX8M_UART1_BASE_ADDR);
+
 	imx8m_early_setup_uart_clock();
 
 	imx8mq_setup_pad(IMX8MQ_PAD_UART1_TXD__UART1_TX | UART_PAD_CTRL);
+	imx8m_uart_setup(uart);
 
-	imx8m_uart_setup_ll();
+	pbl_set_putc(imx_uart_putc, uart);
 
 	putc_ll('>');
 }
diff --git a/arch/arm/boards/phytec-som-imx8mq/lowlevel.c b/arch/arm/boards/phytec-som-imx8mq/lowlevel.c
index f5b9b6c008..ea6ff58cae 100644
--- a/arch/arm/boards/phytec-som-imx8mq/lowlevel.c
+++ b/arch/arm/boards/phytec-som-imx8mq/lowlevel.c
@@ -29,11 +29,15 @@ extern char __dtb_imx8mq_phytec_phycore_som_start[];
 
 static void setup_uart(void)
 {
+	void __iomem *uart = IOMEM(MX8M_UART1_BASE_ADDR);
+
 	imx8m_early_setup_uart_clock();
 
 	imx8mq_setup_pad(IMX8MQ_PAD_UART1_TXD__UART1_TX | UART_PAD_CTRL);
 
-	imx8m_uart_setup_ll();
+	imx8m_uart_setup(uart);
+
+	pbl_set_putc(imx_uart_putc, uart);
 
 	putc_ll('>');
 }
diff --git a/arch/arm/boards/zii-imx8mq-dev/lowlevel.c b/arch/arm/boards/zii-imx8mq-dev/lowlevel.c
index 6400833809..80d2e4c997 100644
--- a/arch/arm/boards/zii-imx8mq-dev/lowlevel.c
+++ b/arch/arm/boards/zii-imx8mq-dev/lowlevel.c
@@ -28,11 +28,14 @@
 
 static void setup_uart(void)
 {
+	void __iomem *uart = IOMEM(MX8M_UART1_BASE_ADDR);
+
 	imx8m_early_setup_uart_clock();
 
 	imx8mq_setup_pad(IMX8MQ_PAD_UART1_TXD__UART1_TX | UART_PAD_CTRL);
+	imx8m_uart_setup(uart);
 
-	imx8m_uart_setup_ll();
+	pbl_set_putc(imx_uart_putc, uart);
 
 	putc_ll('>');
 }
-- 
2.28.0




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