From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Andreas=20F=C3=A4rber?= Subject: [PATCH] tty: serial: meson: Add support for XTAL clock input Date: Mon, 8 Feb 2016 13:49:42 +0100 Message-ID: <1454935783-17027-1-git-send-email-afaerber@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Sender: linux-kernel-owner@vger.kernel.org To: linux-meson@googlegroups.com Cc: Carlo Caione , linux-arm-kernel@lists.infradead.org, Matthias Brugger , Nicolas Saenz , =?UTF-8?q?Andreas=20F=C3=A4rber?= , Greg Kroah-Hartman , Jiri Slaby , "open list:SERIAL DRIVERS" , open list List-Id: linux-serial@vger.kernel.org =46ix the baudrate calculation for 24 MHz XTAL clock found on gxbb plat= forms. Signed-off-by: Andreas F=C3=A4rber --- Forward-ported from vendor kernel. On top of my meson earlycon patch. =20 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) =20 #define AML_UART_PORT_NUM 6 #define AML_UART_DEV_NAME "ttyAML" @@ -299,7 +300,12 @@ static void meson_uart_change_speed(struct uart_po= rt *port, unsigned long baud) =20 val =3D readl(port->membase + AML_UART_REG5); val &=3D ~AML_UART_BAUD_MASK; - val =3D ((port->uartclk * 10 / (baud * 4) + 5) / 10) - 1; + if (port->uartclk =3D=3D 24000000) { + val =3D ((port->uartclk / 3) / baud) - 1; + val |=3D AML_UART_BAUD_XTAL; + } else { + val =3D ((port->uartclk * 10 / (baud * 4) + 5) / 10) - 1; + } val |=3D AML_UART_BAUD_USE; writel(val, port->membase + AML_UART_REG5); } --=20 2.6.2