diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_early.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_early.c | 76 |
1 files changed, 48 insertions, 28 deletions
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c index f8adaf2c9..85a12f032 100644 --- a/drivers/tty/serial/8250/8250_early.c +++ b/drivers/tty/serial/8250/8250_early.c @@ -29,21 +29,27 @@ #include <linux/tty.h> #include <linux/init.h> #include <linux/console.h> +#include <linux/of.h> +#include <linux/of_device.h> #include <linux/serial_reg.h> #include <linux/serial.h> #include <linux/serial_8250.h> #include <asm/io.h> #include <asm/serial.h> -unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offset) +static unsigned int __init serial8250_early_in(struct uart_port *port, int offset) { + offset <<= port->regshift; + switch (port->iotype) { case UPIO_MEM: return readb(port->membase + offset); + case UPIO_MEM16: + return readw(port->membase + offset); case UPIO_MEM32: - return readl(port->membase + (offset << 2)); + return readl(port->membase + offset); case UPIO_MEM32BE: - return ioread32be(port->membase + (offset << 2)); + return ioread32be(port->membase + offset); case UPIO_PORT: return inb(port->iobase + offset); default: @@ -51,17 +57,22 @@ unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offse } } -void __weak __init serial8250_early_out(struct uart_port *port, int offset, int value) +static void __init serial8250_early_out(struct uart_port *port, int offset, int value) { + offset <<= port->regshift; + switch (port->iotype) { case UPIO_MEM: writeb(value, port->membase + offset); break; + case UPIO_MEM16: + writew(value, port->membase + offset); + break; case UPIO_MEM32: - writel(value, port->membase + (offset << 2)); + writel(value, port->membase + offset); break; case UPIO_MEM32BE: - iowrite32be(value, port->membase + (offset << 2)); + iowrite32be(value, port->membase + offset); break; case UPIO_PORT: outb(value, port->iobase + offset); @@ -71,43 +82,27 @@ void __weak __init serial8250_early_out(struct uart_port *port, int offset, int #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) -static void __init wait_for_xmitr(struct uart_port *port) +static void __init serial_putc(struct uart_port *port, int c) { unsigned int status; + serial8250_early_out(port, UART_TX, c); + for (;;) { status = serial8250_early_in(port, UART_LSR); if ((status & BOTH_EMPTY) == BOTH_EMPTY) - return; + break; cpu_relax(); } } -static void __init serial_putc(struct uart_port *port, int c) -{ - wait_for_xmitr(port); - serial8250_early_out(port, UART_TX, c); -} - static void __init early_serial8250_write(struct console *console, - const char *s, unsigned int count, unsigned int loglevel) + const char *s, unsigned int count) { struct earlycon_device *device = console->data; struct uart_port *port = &device->port; - unsigned int ier; - - /* Save the IER and disable interrupts preserving the UUE bit */ - ier = serial8250_early_in(port, UART_IER); - if (ier) - serial8250_early_out(port, UART_IER, ier & UART_IER_UUE); uart_console_write(port, s, count, serial_putc); - - /* Wait for transmitter to become empty and restore the IER */ - wait_for_xmitr(port); - - if (ier) - serial8250_early_out(port, UART_IER, ier); } static void __init init_port(struct earlycon_device *device) @@ -131,7 +126,7 @@ static void __init init_port(struct earlycon_device *device) serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB); } -static int __init early_serial8250_setup(struct earlycon_device *device, +int __init early_serial8250_setup(struct earlycon_device *device, const char *options) { if (!(device->port.membase || device->port.iobase)) @@ -152,3 +147,28 @@ static int __init early_serial8250_setup(struct earlycon_device *device, } EARLYCON_DECLARE(uart8250, early_serial8250_setup); EARLYCON_DECLARE(uart, early_serial8250_setup); +OF_EARLYCON_DECLARE(ns16550, "ns16550", early_serial8250_setup); +OF_EARLYCON_DECLARE(ns16550a, "ns16550a", early_serial8250_setup); +OF_EARLYCON_DECLARE(uart, "nvidia,tegra20-uart", early_serial8250_setup); +OF_EARLYCON_DECLARE(uart, "snps,dw-apb-uart", early_serial8250_setup); + +#ifdef CONFIG_SERIAL_8250_OMAP + +static int __init early_omap8250_setup(struct earlycon_device *device, + const char *options) +{ + struct uart_port *port = &device->port; + + if (!(device->port.membase || device->port.iobase)) + return -ENODEV; + + port->regshift = 2; + device->con->write = early_serial8250_write; + return 0; +} + +OF_EARLYCON_DECLARE(omap8250, "ti,omap2-uart", early_omap8250_setup); +OF_EARLYCON_DECLARE(omap8250, "ti,omap3-uart", early_omap8250_setup); +OF_EARLYCON_DECLARE(omap8250, "ti,omap4-uart", early_omap8250_setup); + +#endif |