From e6c1345f89f0c2fa5d8b0dde733eb80366056632 Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Sat, 25 Apr 2020 11:11:49 +0530 Subject: lib: utils/serial: Skip baudrate config if input frequency is zero We should skip baudrate config for UART8250 and SiFive UART when input frequency is zero. Signed-off-by: Anup Patel Reviewed-by: Atish Patra Reviewed-by: Alistair Francis --- lib/utils/serial/sifive-uart.c | 3 ++- lib/utils/serial/uart8250.c | 12 ++++++++---- 2 files changed, 10 insertions(+), 5 deletions(-) (limited to 'lib/utils') diff --git a/lib/utils/serial/sifive-uart.c b/lib/utils/serial/sifive-uart.c index b82a1b3..72c8a62 100644 --- a/lib/utils/serial/sifive-uart.c +++ b/lib/utils/serial/sifive-uart.c @@ -89,7 +89,8 @@ int sifive_uart_init(unsigned long base, u32 in_freq, u32 baudrate) uart_baudrate = baudrate; /* Configure baudrate */ - set_reg(UART_REG_DIV, uart_min_clk_divisor(in_freq, baudrate)); + if (in_freq) + set_reg(UART_REG_DIV, uart_min_clk_divisor(in_freq, baudrate)); /* Disable interrupts */ set_reg(UART_REG_IE, 0); /* Enable TX */ diff --git a/lib/utils/serial/uart8250.c b/lib/utils/serial/uart8250.c index 42f1881..9635ba8 100644 --- a/lib/utils/serial/uart8250.c +++ b/lib/utils/serial/uart8250.c @@ -100,10 +100,14 @@ int uart8250_init(unsigned long base, u32 in_freq, u32 baudrate, u32 reg_shift, set_reg(UART_IER_OFFSET, 0x00); /* Enable DLAB */ set_reg(UART_LCR_OFFSET, 0x80); - /* Set divisor low byte */ - set_reg(UART_DLL_OFFSET, bdiv & 0xff); - /* Set divisor high byte */ - set_reg(UART_DLM_OFFSET, (bdiv >> 8) & 0xff); + + if (bdiv) { + /* Set divisor low byte */ + set_reg(UART_DLL_OFFSET, bdiv & 0xff); + /* Set divisor high byte */ + set_reg(UART_DLM_OFFSET, (bdiv >> 8) & 0xff); + } + /* 8 bits, no parity, one stop bit */ set_reg(UART_LCR_OFFSET, 0x03); /* Enable FIFO */ -- cgit v1.2.3