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author | Mark Brown <broonie@kernel.org> | 2020-08-25 13:01:46 +0300 |
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committer | Mark Brown <broonie@kernel.org> | 2020-08-25 13:01:46 +0300 |
commit | 3bec5b6aae830355e786e204b20a7cea38c3a8ed (patch) | |
tree | fd597b87faf55ceb2a207ee94f4feca6276696db /drivers/tty/serial/imx_earlycon.c | |
parent | a577f3456c0a2fac3dee037c483753e6e68f3e49 (diff) | |
parent | d012a7190fc1fd72ed48911e77ca97ba4521bccd (diff) | |
download | linux-3bec5b6aae830355e786e204b20a7cea38c3a8ed.tar.xz |
Merge tag 'v5.9-rc2' into regulator-5.9
Linux 5.9-rc2
Diffstat (limited to 'drivers/tty/serial/imx_earlycon.c')
-rw-r--r-- | drivers/tty/serial/imx_earlycon.c | 50 |
1 files changed, 50 insertions, 0 deletions
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"); |