tty/serial: pl011: add generic earlycon support
Add earlycon support for the pl011 serial port. This allows enabling the pl011 for console when early_params are processed. This is based on the arm64 earlyprintk support and is intended to replace it. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
d2fd6810a8
commit
0d3c673e78
|
@ -883,6 +883,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
|
|||
which are not unmapped.
|
||||
|
||||
earlycon= [KNL] Output early console device and options.
|
||||
|
||||
uart[8250],io,<addr>[,options]
|
||||
uart[8250],mmio,<addr>[,options]
|
||||
uart[8250],mmio32,<addr>[,options]
|
||||
|
@ -892,6 +893,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
|
|||
(mmio) or 32-bit (mmio32).
|
||||
The options are the same as for ttyS, above.
|
||||
|
||||
pl011,<addr>
|
||||
Start an early, polled-mode console on a pl011 serial
|
||||
port at the specified address. The pl011 serial port
|
||||
must already be setup and configured. Options are not
|
||||
yet supported.
|
||||
|
||||
earlyprintk= [X86,SH,BLACKFIN,ARM]
|
||||
earlyprintk=vga
|
||||
earlyprintk=efi
|
||||
|
|
|
@ -60,6 +60,7 @@ config SERIAL_AMBA_PL011_CONSOLE
|
|||
bool "Support for console on AMBA serial port"
|
||||
depends on SERIAL_AMBA_PL011=y
|
||||
select SERIAL_CORE_CONSOLE
|
||||
select SERIAL_EARLYCON
|
||||
---help---
|
||||
Say Y here if you wish to use an AMBA PrimeCell UART as the system
|
||||
console (the system console is the device which receives all kernel
|
||||
|
|
|
@ -303,7 +303,7 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *
|
|||
|
||||
/* Optionally make use of an RX channel as well */
|
||||
chan = dma_request_slave_channel(dev, "rx");
|
||||
|
||||
|
||||
if (!chan && plat->dma_rx_param) {
|
||||
chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param);
|
||||
|
||||
|
@ -2045,6 +2045,34 @@ static struct console amba_console = {
|
|||
};
|
||||
|
||||
#define AMBA_CONSOLE (&amba_console)
|
||||
|
||||
static void pl011_putc(struct uart_port *port, int c)
|
||||
{
|
||||
while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
|
||||
;
|
||||
writeb(c, port->membase + UART01x_DR);
|
||||
while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY)
|
||||
;
|
||||
}
|
||||
|
||||
static void pl011_early_write(struct console *con, const char *s, unsigned n)
|
||||
{
|
||||
struct earlycon_device *dev = con->data;
|
||||
|
||||
uart_console_write(&dev->port, s, n, pl011_putc);
|
||||
}
|
||||
|
||||
static int __init pl011_early_console_setup(struct earlycon_device *device,
|
||||
const char *opt)
|
||||
{
|
||||
if (!device->port.membase)
|
||||
return -ENODEV;
|
||||
|
||||
device->con->write = pl011_early_write;
|
||||
return 0;
|
||||
}
|
||||
EARLYCON_DECLARE(pl011, pl011_early_console_setup);
|
||||
|
||||
#else
|
||||
#define AMBA_CONSOLE NULL
|
||||
#endif
|
||||
|
|
Loading…
Reference in New Issue