If CONFIG_SYS_SKIP_UART_INIT is enabled, calculate the current baud rate and update the "console" environment variable.
Signed-off-by: Jim Liu JJLIU0@nuvoton.com --- board/nuvoton/arbel_evb/Kconfig | 1 + board/nuvoton/common/Kconfig | 9 +++++ board/nuvoton/common/Makefile | 1 + board/nuvoton/common/common.c | 71 +++++++++++++++++++++++++++++++++ board/nuvoton/common/common.h | 11 +++++ board/nuvoton/poleg_evb/Kconfig | 1 + 6 files changed, 94 insertions(+) create mode 100644 board/nuvoton/common/Kconfig create mode 100644 board/nuvoton/common/Makefile create mode 100644 board/nuvoton/common/common.c create mode 100644 board/nuvoton/common/common.h
diff --git a/board/nuvoton/arbel_evb/Kconfig b/board/nuvoton/arbel_evb/Kconfig index 33c589f1fb..ed1c1ad8ee 100644 --- a/board/nuvoton/arbel_evb/Kconfig +++ b/board/nuvoton/arbel_evb/Kconfig @@ -15,4 +15,5 @@ config SYS_MEM_TOP_HIDE help Reserve memory for ECC/GFX/OPTEE/TIP/CP.
+source "board/nuvoton/common/Kconfig" endif diff --git a/board/nuvoton/common/Kconfig b/board/nuvoton/common/Kconfig new file mode 100644 index 0000000000..61de7bc5f8 --- /dev/null +++ b/board/nuvoton/common/Kconfig @@ -0,0 +1,9 @@ +if ARCH_NPCM + +config SYS_SKIP_UART_INIT + bool "Skip UART initialization" + depends on NPCM_SERIAL + help + Select this if the UART you want to use is already + initialized by the time U-Boot starts its execution. +endif diff --git a/board/nuvoton/common/Makefile b/board/nuvoton/common/Makefile new file mode 100644 index 0000000000..52e77185c4 --- /dev/null +++ b/board/nuvoton/common/Makefile @@ -0,0 +1 @@ +obj-y += common.o diff --git a/board/nuvoton/common/common.c b/board/nuvoton/common/common.c new file mode 100644 index 0000000000..6da9d93e80 --- /dev/null +++ b/board/nuvoton/common/common.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2023 Nuvoton Technology Corp. + */ + +#include <common.h> +#include <clk.h> +#include <dm.h> +#include <env.h> +#include <serial.h> +#include <linux/delay.h> + +#define UART_DLL 0x0 +#define UART_DLM 0x4 +#define UART_LCR 0xc +#define LCR_DLAB BIT(7) + +int board_set_console(void) +{ + const unsigned long baudrate_table[] = CFG_SYS_BAUDRATE_TABLE; + struct udevice *dev = gd->cur_serial_dev; + unsigned int baudrate, max_delta; + void __iomem *uart_reg; + struct clk clk; + char string[32]; + u32 uart_clk; + u8 dll, dlm; + u16 divisor; + int ret, i; + + /* If uart init is skipped, update the actual baudrate in boot arguments */ + if (!IS_ENABLED(CONFIG_SYS_SKIP_UART_INIT)) + return 0; + if (!dev) + return 0; + uart_reg = dev_read_addr_ptr(dev); + ret = clk_get_by_index(dev, 0, &clk); + if (ret) + return 0; + uart_clk = clk_get_rate(&clk); + setbits_8(uart_reg + UART_LCR, LCR_DLAB); + dll = readb(uart_reg + UART_DLL); + dlm = readb(uart_reg + UART_DLM); + clrbits_8(uart_reg + UART_LCR, LCR_DLAB); + divisor = dll | (dlm << 8); + baudrate = uart_clk / ((16 * (divisor + 2))); + for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) { + max_delta = baudrate_table[i] / 20; + if (abs(baudrate - baudrate_table[i]) < max_delta) { + /* The baudrate is supported */ + gd->baudrate = baudrate_table[i]; + break; + } + } + if (i == ARRAY_SIZE(baudrate_table)) { + /* current baudrate is not suitable, set to default */ + divisor = DIV_ROUND_CLOSEST(uart_clk, 16 * gd->baudrate) - 2; + setbits_8(uart_reg + UART_LCR, LCR_DLAB); + writeb(divisor & 0xff, uart_reg + UART_DLL); + writeb(divisor >> 8, uart_reg + UART_DLM); + clrbits_8(uart_reg + UART_LCR, LCR_DLAB); + udelay(100); + printf("\r\nUART(source %u): change baudrate from %u to %u\n", + uart_clk, baudrate, uart_clk / ((16 * (divisor + 2)))); + } + debug("Set env baudrate=%u\n", gd->baudrate); + snprintf(string, sizeof(string), "ttyS0,%un8", gd->baudrate); + env_set("console", string); + + return 0; +} diff --git a/board/nuvoton/common/common.h b/board/nuvoton/common/common.h new file mode 100644 index 0000000000..64a09670cb --- /dev/null +++ b/board/nuvoton/common/common.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2023 Nuvoton Technology Corp. + */ + +#ifndef _NUVOTON_COMMON_H +#define _NUVOTON_COMMON_H + +int board_set_console(void); + +#endif /* _NUVOTON_COMMON_H */ diff --git a/board/nuvoton/poleg_evb/Kconfig b/board/nuvoton/poleg_evb/Kconfig index d3f4c1dd81..6f7f1ef157 100644 --- a/board/nuvoton/poleg_evb/Kconfig +++ b/board/nuvoton/poleg_evb/Kconfig @@ -22,4 +22,5 @@ config TARGET_POLEG_EVB
endchoice
+source "board/nuvoton/common/Kconfig" endif