GKI kernel requires drivers built as modules including console driver, so add the support that imx serial console driver can be built as module. The changes of the patch: - imx console driver can be built as module. - move out earlycon code to separated driver like imx_earlycon.c, and imx earlycon driver only support build-in. Signed-off-by: Fugang Duan <fugang.duan@xxxxxxx> --- drivers/tty/serial/Kconfig | 17 +++++++---- drivers/tty/serial/Makefile | 1 + drivers/tty/serial/imx.c | 37 ++--------------------- drivers/tty/serial/imx_earlycon.c | 50 +++++++++++++++++++++++++++++++ 4 files changed, 65 insertions(+), 40 deletions(-) diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index adf9e80e7dc9..890cbf214561 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -502,20 +502,27 @@ config SERIAL_IMX can enable its onboard serial port by enabling this option. config SERIAL_IMX_CONSOLE - bool "Console on IMX serial port" - depends on SERIAL_IMX=y + tristate "Console on IMX serial port" + depends on SERIAL_IMX select SERIAL_CORE_CONSOLE - select SERIAL_EARLYCON if OF help If you have enabled the serial port on the Freescale IMX - CPU you can make it the console by answering Y to this option. + CPU you can make it the console by answering Y/M to this option. - Even if you say Y here, the currently visible virtual console + Even if you say Y/M here, the currently visible virtual console (/dev/tty0) will still be used as the system console by default, but you can alter that using a kernel command line option such as "console=ttymxc0". (Try "man bootparam" or see the documentation of your bootloader about how to pass options to the kernel at boot time.) +config SERIAL_IMX_EARLYCON + bool "Earlycon on IMX serial port" + depends OF + select SERIAL_EARLYCON if OF + help + If you have enabled the earlycon on the Freescale IMX + CPU you can make it the earlycon by answering Y to this option. + config SERIAL_UARTLITE tristate "Xilinx uartlite serial port support" depends on HAS_IOMEM diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile index d056ee6cca33..caf167f0c10a 100644 --- a/drivers/tty/serial/Makefile +++ b/drivers/tty/serial/Makefile @@ -43,6 +43,7 @@ obj-$(CONFIG_SERIAL_ZS) += zs.o obj-$(CONFIG_SERIAL_SH_SCI) += sh-sci.o obj-$(CONFIG_SERIAL_CPM) += cpm_uart/ obj-$(CONFIG_SERIAL_IMX) += imx.o +obj-$(CONFIG_SERIAL_IMX_EARLYCON) += imx_earlycon.o obj-$(CONFIG_SERIAL_MPC52xx) += mpc52xx_uart.o obj-$(CONFIG_SERIAL_ICOM) += icom.o obj-$(CONFIG_SERIAL_MESON) += meson_uart.o diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index f4d68109bc8b..c8402ee2a78e 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -361,7 +361,7 @@ static inline int imx_uart_is_imx6q(struct imx_port *sport) /* * Save and restore functions for UCR1, UCR2 and UCR3 registers */ -#if defined(CONFIG_SERIAL_IMX_CONSOLE) +#if IS_ENABLED(CONFIG_SERIAL_IMX_CONSOLE) static void imx_uart_ucrs_save(struct imx_port *sport, struct imx_port_ucrs *ucr) { @@ -1913,7 +1913,7 @@ static const struct uart_ops imx_uart_pops = { static struct imx_port *imx_uart_ports[UART_NR]; -#ifdef CONFIG_SERIAL_IMX_CONSOLE +#if IS_ENABLED(CONFIG_SERIAL_IMX_CONSOLE) static void imx_uart_console_putchar(struct uart_port *port, int ch) { struct imx_port *sport = (struct imx_port *)port; @@ -2110,39 +2110,6 @@ static struct console imx_uart_console = { #define IMX_CONSOLE &imx_uart_console -#ifdef CONFIG_OF -static void imx_uart_console_early_putchar(struct uart_port *port, int ch) -{ - struct imx_port *sport = (struct imx_port *)port; - - while (imx_uart_readl(sport, IMX21_UTS) & UTS_TXFULL) - cpu_relax(); - - imx_uart_writel(sport, ch, URTX0); -} - -static void imx_uart_console_early_write(struct console *con, const char *s, - unsigned count) -{ - struct earlycon_device *dev = con->data; - - uart_console_write(&dev->port, s, count, imx_uart_console_early_putchar); -} - -static int __init -imx_console_early_setup(struct earlycon_device *dev, const char *opt) -{ - if (!dev->port.membase) - return -ENODEV; - - dev->con->write = imx_uart_console_early_write; - - return 0; -} -OF_EARLYCON_DECLARE(ec_imx6q, "fsl,imx6q-uart", imx_console_early_setup); -OF_EARLYCON_DECLARE(ec_imx21, "fsl,imx21-uart", imx_console_early_setup); -#endif - #else #define IMX_CONSOLE NULL #endif diff --git a/drivers/tty/serial/imx_earlycon.c b/drivers/tty/serial/imx_earlycon.c new file mode 100644 index 000000000000..795606e1a22f --- /dev/null +++ b/drivers/tty/serial/imx_earlycon.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2020 NXP + */ + +#include <linux/module.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/serial_core.h> +#include <linux/serial.h> +#include <linux/delay.h> +#include <linux/of.h> +#include <linux/io.h> + +#define URTX0 0x40 /* Transmitter Register */ +#define UTS_TXFULL (1<<4) /* TxFIFO full */ +#define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/ + +static void imx_uart_console_early_putchar(struct uart_port *port, int ch) +{ + while (readl_relaxed(port->membase + IMX21_UTS) & UTS_TXFULL) + cpu_relax(); + + writel_relaxed(ch, port->membase + URTX0); +} + +static void imx_uart_console_early_write(struct console *con, const char *s, + unsigned count) +{ + struct earlycon_device *dev = con->data; + + uart_console_write(&dev->port, s, count, imx_uart_console_early_putchar); +} + +static int __init +imx_console_early_setup(struct earlycon_device *dev, const char *opt) +{ + if (!dev->port.membase) + return -ENODEV; + + dev->con->write = imx_uart_console_early_write; + + return 0; +} +OF_EARLYCON_DECLARE(ec_imx6q, "fsl,imx6q-uart", imx_console_early_setup); +OF_EARLYCON_DECLARE(ec_imx21, "fsl,imx21-uart", imx_console_early_setup); + +MODULE_AUTHOR("NXP"); +MODULE_DESCRIPTION("IMX earlycon driver"); +MODULE_LICENSE("GPL"); -- 2.17.1