stm32mp1: Allow to activate CONFIG_DEBUG_UART

Add the needed information to enable the debug uart
to have printf before the serial driver probe
(so before probe for clock, pincontrol and reset drivers)

To enable the debug on uart 4 (default console):
+ CONFIG_DEBUG_UART=y
+ CONFIG_DEBUG_UART_STM32=y

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>

diff --git a/arch/arm/mach-stm32mp/Kconfig b/arch/arm/mach-stm32mp/Kconfig
index ccbeb5c..abceede 100644 (file)
--- a/arch/arm/mach-stm32mp/Kconfig
+++ b/arch/arm/mach-stm32mp/Kconfig
@@ -54,4 +54,19 @@ config SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION_MMC2
 
 source "board/st/stm32mp1/Kconfig"
 
+# currently activated for debug / should be deactivated for real product
+if DEBUG_UART
+
+config DEBUG_UART_BOARD_INIT
+       default y
+
+# debug on UART4 by default
+config DEBUG_UART_BASE
+       default 0x40010000
+
+# clock source is HSI on reset
+config DEBUG_UART_CLOCK
+       default 64000000
+endif
+
 endif

diff --git a/arch/arm/mach-stm32mp/cpu.c b/arch/arm/mach-stm32mp/cpu.c
index dfcbbd2..2deee09 100644 (file)
--- a/arch/arm/mach-stm32mp/cpu.c
+++ b/arch/arm/mach-stm32mp/cpu.c
@@ -4,6 +4,7 @@
  */
 #include <common.h>
 #include <clk.h>
+#include <debug_uart.h>
 #include <asm/io.h>
 #include <asm/arch/stm32.h>
 #include <asm/arch/sys_proto.h>
@@ -152,6 +153,8 @@ static u32 get_bootmode(void)
  */
 int arch_cpu_init(void)
 {
+       u32 boot_mode;
+
        /* early armv7 timer init: needed for polling */
        timer_init();
 
@@ -160,8 +163,17 @@ int arch_cpu_init(void)
 
        security_init();
 #endif
+
        /* get bootmode from BootRom context: saved in TAMP register */
-       get_bootmode();
+       boot_mode = get_bootmode();
+
+       if ((boot_mode & TAMP_BOOT_DEVICE_MASK) == BOOT_SERIAL_UART)
+               gd->flags |= GD_FLG_SILENT | GD_FLG_DISABLE_CONSOLE;
+#if defined(CONFIG_DEBUG_UART) && \
+       (!defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD))
+       else
+               debug_uart_init();
+#endif
 
        return 0;
 }

diff --git a/arch/arm/mach-stm32mp/include/mach/stm32.h b/arch/arm/mach-stm32mp/include/mach/stm32.h
index a814201..129f9f5 100644 (file)
--- a/arch/arm/mach-stm32mp/include/mach/stm32.h
+++ b/arch/arm/mach-stm32mp/include/mach/stm32.h
@@ -17,6 +17,18 @@
 #define STM32_ETZPC_BASE               0x5C007000
 #define STM32_TAMP_BASE                        0x5C00A000
 
+#ifdef CONFIG_DEBUG_UART_BASE
+/* hardcoded value can be only used for DEBUG UART */
+#define STM32_USART1_BASE              0x5C000000
+#define STM32_USART2_BASE              0x4000E000
+#define STM32_USART3_BASE              0x4000F000
+#define STM32_UART4_BASE               0x40010000
+#define STM32_UART5_BASE               0x40011000
+#define STM32_USART6_BASE              0x44003000
+#define STM32_UART7_BASE               0x40018000
+#define STM32_UART8_BASE               0x40019000
+#endif
+
 #define STM32_SYSRAM_BASE              0x2FFC0000
 #define STM32_SYSRAM_SIZE              SZ_256K
 

diff --git a/board/st/stm32mp1/board.c b/board/st/stm32mp1/board.c
index 956768f..5f31ea9 100644 (file)
--- a/board/st/stm32mp1/board.c
+++ b/board/st/stm32mp1/board.c
@@ -10,6 +10,33 @@
 #include <power/pmic.h>
 #include <power/stpmu1.h>
 
+#ifdef CONFIG_DEBUG_UART_BOARD_INIT
+void board_debug_uart_init(void)
+{
+#if (CONFIG_DEBUG_UART_BASE == STM32_UART4_BASE)
+
+#define RCC_MP_APB1ENSETR (STM32_RCC_BASE + 0x0A00)
+#define RCC_MP_AHB4ENSETR (STM32_RCC_BASE + 0x0A28)
+
+       /* UART4 clock enable */
+       setbits_le32(RCC_MP_APB1ENSETR, BIT(16));
+
+#define GPIOG_BASE 0x50008000
+       /* GPIOG clock enable */
+       writel(BIT(6), RCC_MP_AHB4ENSETR);
+       /* GPIO configuration for EVAL board
+        * => Uart4 TX = G11
+        */
+       writel(0xffbfffff, GPIOG_BASE + 0x00);
+       writel(0x00006000, GPIOG_BASE + 0x24);
+#else
+
+#error("CONFIG_DEBUG_UART_BASE: not supported value")
+
+#endif
+}
+#endif
+
 #ifdef CONFIG_PMIC_STPMU1
 int board_ddr_power_init(void)
 {