[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon
Rob Herring
robherring2 at gmail.com
Fri Apr 18 15:19:56 PDT 2014
From: Rob Herring <robh at kernel.org>
With the generic earlycon infrastructure in place, convert the 8250
early console to use it.
Signed-off-by: Rob Herring <robh at kernel.org>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Cc: Jiri Slaby <jslaby at suse.cz>
---
drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
drivers/tty/serial/8250/Kconfig | 1 +
2 files changed, 16 insertions(+), 123 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index c100d63..e83c9db 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -35,18 +35,8 @@
#include <linux/serial_8250.h>
#include <asm/io.h>
#include <asm/serial.h>
-#ifdef CONFIG_FIX_EARLYCON_MEM
-#include <asm/pgtable.h>
-#include <asm/fixmap.h>
-#endif
-struct early_serial8250_device {
- struct uart_port port;
- char options[16]; /* e.g., 115200n8 */
- unsigned int baud;
-};
-
-static struct early_serial8250_device early_device;
+static struct earlycon_device *early_device;
unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offset)
{
@@ -100,7 +90,7 @@ static void __init serial_putc(struct uart_port *port, int c)
static void __init early_serial8250_write(struct console *console,
const char *s, unsigned int count)
{
- struct uart_port *port = &early_device.port;
+ struct uart_port *port = &early_device->port;
unsigned int ier;
/* Save the IER and disable interrupts */
@@ -129,7 +119,7 @@ static unsigned int __init probe_baud(struct uart_port *port)
return (port->uartclk / 16) / quot;
}
-static void __init init_port(struct early_serial8250_device *device)
+static void __init init_port(struct earlycon_device *device)
{
struct uart_port *port = &device->port;
unsigned int divisor;
@@ -148,128 +138,32 @@ static void __init init_port(struct early_serial8250_device *device)
serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB);
}
-static int __init parse_options(struct early_serial8250_device *device,
- char *options)
-{
- struct uart_port *port = &device->port;
- int mmio, mmio32, length;
-
- if (!options)
- return -ENODEV;
-
- port->uartclk = BASE_BAUD * 16;
-
- mmio = !strncmp(options, "mmio,", 5);
- mmio32 = !strncmp(options, "mmio32,", 7);
- if (mmio || mmio32) {
- port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
- port->mapbase = simple_strtoul(options + (mmio ? 5 : 7),
- &options, 0);
- if (mmio32)
- port->regshift = 2;
-#ifdef CONFIG_FIX_EARLYCON_MEM
- set_fixmap_nocache(FIX_EARLYCON_MEM_BASE,
- port->mapbase & PAGE_MASK);
- port->membase =
- (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
- port->membase += port->mapbase & ~PAGE_MASK;
-#else
- port->membase = ioremap_nocache(port->mapbase, 64);
- if (!port->membase) {
- printk(KERN_ERR "%s: Couldn't ioremap 0x%llx\n",
- __func__,
- (unsigned long long) port->mapbase);
- return -ENOMEM;
- }
-#endif
- } else if (!strncmp(options, "io,", 3)) {
- port->iotype = UPIO_PORT;
- port->iobase = simple_strtoul(options + 3, &options, 0);
- mmio = 0;
- } else
- return -EINVAL;
-
- options = strchr(options, ',');
- if (options) {
- options++;
- device->baud = simple_strtoul(options, NULL, 0);
- length = min(strcspn(options, " ") + 1,
- (size_t)(sizeof(device->options)));
- strlcpy(device->options, options, length);
- } else {
- device->baud = probe_baud(port);
- snprintf(device->options, sizeof(device->options), "%u",
- device->baud);
- }
-
- if (mmio || mmio32)
- printk(KERN_INFO
- "Early serial console at MMIO%s 0x%llx (options '%s')\n",
- mmio32 ? "32" : "",
- (unsigned long long)port->mapbase,
- device->options);
- else
- printk(KERN_INFO
- "Early serial console at I/O port 0x%lx (options '%s')\n",
- port->iobase,
- device->options);
-
- return 0;
-}
-
-static struct console early_serial8250_console __initdata = {
- .name = "uart",
- .write = early_serial8250_write,
- .flags = CON_PRINTBUFFER | CON_BOOT,
- .index = -1,
-};
-
-static int __init early_serial8250_setup(char *options)
+static int __init early_serial8250_setup(struct earlycon_device *device,
+ const char *options)
{
- struct early_serial8250_device *device = &early_device;
- int err;
-
- if (device->port.membase || device->port.iobase)
+ if (!(device->port.membase || device->port.iobase))
return 0;
- err = parse_options(device, options);
- if (err < 0)
- return err;
+ if (!device->baud)
+ device->baud = probe_baud(&device->port);
init_port(device);
- return 0;
-}
-
-int __init setup_early_serial8250_console(char *cmdline)
-{
- char *options;
- int err;
-
- options = strstr(cmdline, "uart8250,");
- if (!options) {
- options = strstr(cmdline, "uart,");
- if (!options)
- return 0;
- }
-
- options = strchr(cmdline, ',') + 1;
- err = early_serial8250_setup(options);
- if (err < 0)
- return err;
-
- register_console(&early_serial8250_console);
+ early_device = device;
+ device->con->write = early_serial8250_write;
return 0;
}
+EARLYCON_DECLARE(uart8250, early_serial8250_setup);
+EARLYCON_DECLARE(uart, early_serial8250_setup);
int serial8250_find_port_for_earlycon(void)
{
- struct early_serial8250_device *device = &early_device;
- struct uart_port *port = &device->port;
+ struct earlycon_device *device = early_device;
+ struct uart_port *port = device ? &device->port : NULL;
int line;
int ret;
- if (!device->port.membase && !device->port.iobase)
+ if (!port || (!port->membase && !port->iobase))
return -ENODEV;
line = serial8250_find_port(port);
@@ -284,5 +178,3 @@ int serial8250_find_port_for_earlycon(void)
return ret;
}
-
-early_param("earlycon", setup_early_serial8250_console);
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index 91f1d83..349ee59 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -61,6 +61,7 @@ config SERIAL_8250_CONSOLE
bool "Console on 8250/16550 and compatible serial port"
depends on SERIAL_8250=y
select SERIAL_CORE_CONSOLE
+ select SERIAL_EARLYCON
---help---
If you say Y here, it will be possible to use a serial port as the
system console (the system console is the device which receives all
--
1.9.1
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