diff options
| author | Gerald Baeza <gerald.baeza@st.com> | 2017-07-27 16:50:20 +0000 |
|---|---|---|
| committer | Olof Johansson <olof@lixom.net> | 2018-11-12 10:20:41 -0800 |
| commit | d88bb418b7cc0525254cb1723a40b7b4133bad01 (patch) | |
| tree | 824e07c884530059fcd56ee8a63c4eaf6715d20e /arch/arm | |
| parent | ccda4af0f4b92f7b4c308d3acc262f4a7e3affad (diff) | |
ARM: stm32: debug: add low-level debug support
This adds low-level debug support on USART1 for STM32F4
and STM32F7.
Compiled via 'CONFIG_DEBUG_LL' and 'CONFIG_EARLY_PRINTK'.
Enabled via 'earlyprintk' in bootargs.
Signed-off-by: Gerald Baeza <gerald.baeza@st.com>
Signed-off-by: Bich Hemon <bich.hemon@st.com>
Acked-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/Kconfig.debug | 27 | ||||
| -rw-r--r-- | arch/arm/include/debug/stm32.S | 41 |
2 files changed, 68 insertions, 0 deletions
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index d6a49f59ecd9..672147e59ef3 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -1192,6 +1192,28 @@ choice If unsure, say N. + config STM32F4_DEBUG_UART + bool "Use STM32F4 UART for low-level debug" + depends on ARCH_STM32 + select DEBUG_STM32_UART + help + Say Y here if you want kernel low-level debugging support + on STM32F4 based platforms, which default UART is wired on + USART1. + + If unsure, say N. + + config STM32F7_DEBUG_UART + bool "Use STM32F7 UART for low-level debug" + depends on ARCH_STM32 + select DEBUG_STM32_UART + help + Say Y here if you want kernel low-level debugging support + on STM32F7 based platforms, which default UART is wired on + USART1. + + If unsure, say N. + config TEGRA_DEBUG_UART_AUTO_ODMDATA bool "Kernel low-level debugging messages via Tegra UART via ODMDATA" depends on ARCH_TEGRA @@ -1476,6 +1498,10 @@ config DEBUG_STI_UART bool depends on ARCH_STI +config DEBUG_STM32_UART + bool + depends on ARCH_STM32 + config DEBUG_SIRFSOC_UART bool depends on ARCH_SIRF @@ -1525,6 +1551,7 @@ config DEBUG_LL_INCLUDE default "debug/s5pv210.S" if DEBUG_S5PV210_UART default "debug/sirf.S" if DEBUG_SIRFSOC_UART default "debug/sti.S" if DEBUG_STI_UART + default "debug/stm32.S" if DEBUG_STM32_UART default "debug/tegra.S" if DEBUG_TEGRA_UART default "debug/ux500.S" if DEBUG_UX500_UART default "debug/vexpress.S" if DEBUG_VEXPRESS_UART0_DETECT diff --git a/arch/arm/include/debug/stm32.S b/arch/arm/include/debug/stm32.S new file mode 100644 index 000000000000..1abb32f685fd --- /dev/null +++ b/arch/arm/include/debug/stm32.S @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) STMicroelectronics SA 2017 - All Rights Reserved + * Author: Gerald Baeza <gerald.baeza@st.com> for STMicroelectronics. + */ + +#define STM32_UART_BASE 0x40011000 /* USART1 */ + +#ifdef CONFIG_STM32F4_DEBUG_UART +#define STM32_USART_SR_OFF 0x00 +#define STM32_USART_TDR_OFF 0x04 +#endif + +#ifdef CONFIG_STM32F7_DEBUG_UART +#define STM32_USART_SR_OFF 0x1C +#define STM32_USART_TDR_OFF 0x28 +#endif + +#define STM32_USART_TC (1 << 6) /* Tx complete */ +#define STM32_USART_TXE (1 << 7) /* Tx data reg empty */ + +.macro addruart, rp, rv, tmp + ldr \rp, =STM32_UART_BASE @ physical base + ldr \rv, =STM32_UART_BASE @ virt base /* NoMMU */ +.endm + +.macro senduart,rd,rx + strb \rd, [\rx, #STM32_USART_TDR_OFF] +.endm + +.macro waituart,rd,rx +1001: ldr \rd, [\rx, #(STM32_USART_SR_OFF)] @ Read Status Register + tst \rd, #STM32_USART_TXE @ TXE = 1 = tx empty + beq 1001b +.endm + +.macro busyuart,rd,rx +1001: ldr \rd, [\rx, #(STM32_USART_SR_OFF)] @ Read Status Register + tst \rd, #STM32_USART_TC @ TC = 1 = tx complete + beq 1001b +.endm |