Fix the baudrate calculation for 24 MHz XTAL clock found on gxbb platforms.
Signed-off-by: Andreas Färber <[email protected]> --- Forward-ported from vendor kernel. On top of my meson earlycon patch. drivers/tty/serial/meson_uart.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c index 9efcfa2de31e..4415631bab17 100644 --- a/drivers/tty/serial/meson_uart.c +++ b/drivers/tty/serial/meson_uart.c @@ -78,6 +78,7 @@ /* AML_UART_REG5 bits */ #define AML_UART_BAUD_MASK 0x7fffff #define AML_UART_BAUD_USE BIT(23) +#define AML_UART_BAUD_XTAL BIT(24) #define AML_UART_PORT_NUM 6 #define AML_UART_DEV_NAME "ttyAML" @@ -299,7 +300,12 @@ static void meson_uart_change_speed(struct uart_port *port, unsigned long baud) val = readl(port->membase + AML_UART_REG5); val &= ~AML_UART_BAUD_MASK; - val = ((port->uartclk * 10 / (baud * 4) + 5) / 10) - 1; + if (port->uartclk == 24000000) { + val = ((port->uartclk / 3) / baud) - 1; + val |= AML_UART_BAUD_XTAL; + } else { + val = ((port->uartclk * 10 / (baud * 4) + 5) / 10) - 1; + } val |= AML_UART_BAUD_USE; writel(val, port->membase + AML_UART_REG5); } -- 2.6.2
