From: Samium Gromoff <_deepfire@feelingofgreen.ru>
Provide MMIO32 support in 8250_early (aka earlycon)
[randy.dunlap@oracle.com: fix printk format warnings]
[akpm@linux-foundation.org: fix printk args some more]
Signed-off-by: Samium Gromoff <_deepfire@feelingofgreen.ru>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
Documentation/kernel-parameters.txt | 3 ++
drivers/serial/8250_early.c | 57 +++++++++++++++++++++++++---------
2 files changed, 45 insertions(+), 15 deletions(-)
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index d9239d5..f77ed13 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -687,8 +687,11 @@ and is between 256 and 4096 characters. It is defined in the file
earlycon= [KNL] Output early console device and options.
uart[8250],io,<addr>[,options]
uart[8250],mmio,<addr>[,options]
+ uart[8250],mmio32,<addr>[,options]
Start an early, polled-mode console on the 8250/16550
UART at the specified I/O port or MMIO address.
+ MMIO inter-register address stride is either 8bit (mmio)
+ or 32bit (mmio32).
The options are the same as for ttyS, above.
earlyprintk= [X86,SH,BLACKFIN]
diff --git a/drivers/serial/8250_early.c b/drivers/serial/8250_early.c
index f279745..b745792 100644
--- a/drivers/serial/8250_early.c
+++ b/drivers/serial/8250_early.c
@@ -19,9 +19,11 @@
* The user can specify the device directly, e.g.,
* earlycon=uart8250,io,0x3f8,9600n8
* earlycon=uart8250,mmio,0xff5e0000,115200n8
+ * earlycon=uart8250,mmio32,0xff5e0000,115200n8
* or
* console=uart8250,io,0x3f8,9600n8
* console=uart8250,mmio,0xff5e0000,115200n8
+ * console=uart8250,mmio32,0xff5e0000,115200n8
*/
#include <linux/tty.h>
@@ -48,18 +50,31 @@ static struct early_serial8250_device early_device;
static unsigned int __init serial_in(struct uart_port *port, int offset)
{
- if (port->iotype == UPIO_MEM)
+ switch (port->iotype) {
+ case UPIO_MEM:
return readb(port->membase + offset);
- else
+ case UPIO_MEM32:
+ return readl(port->membase + (offset << 2));
+ case UPIO_PORT:
return inb(port->iobase + offset);
+ default:
+ return 0;
+ }
}
static void __init serial_out(struct uart_port *port, int offset, int value)
{
- if (port->iotype == UPIO_MEM)
+ switch (port->iotype) {
+ case UPIO_MEM:
writeb(value, port->membase + offset);
- else
+ break;
+ case UPIO_MEM32:
+ writel(value, port->membase + (offset << 2));
+ break;
+ case UPIO_PORT:
outb(value, port->iobase + offset);
+ break;
+ }
}
#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
@@ -137,15 +152,21 @@ static int __init parse_options(struct early_serial8250_device *device,
char *options)
{
struct uart_port *port = &device->port;
- int mmio, length;
+ int mmio, mmio32, length;
if (!options)
return -ENODEV;
port->uartclk = BASE_BAUD * 16;
- if (!strncmp(options, "mmio,", 5)) {
- port->iotype = UPIO_MEM;
- port->mapbase = simple_strtoul(options + 5, &options, 0);
+
+ 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);
@@ -157,11 +178,10 @@ static int __init parse_options(struct early_serial8250_device *device,
if (!port->membase) {
printk(KERN_ERR "%s: Couldn't ioremap 0x%llx\n",
__func__,
- (unsigned long long)port->mapbase);
+ (unsigned long long) port->mapbase);
return -ENOMEM;
}
#endif
- mmio = 1;
} else if (!strncmp(options, "io,", 3)) {
port->iotype = UPIO_PORT;
port->iobase = simple_strtoul(options + 3, &options, 0);
@@ -181,11 +201,18 @@ static int __init parse_options(struct early_serial8250_device *device,
device->baud);
}
- printk(KERN_INFO "Early serial console at %s 0x%llx (options '%s')\n",
- mmio ? "MMIO" : "I/O port",
- mmio ? (unsigned long long) port->mapbase
- : (unsigned long long) port->iobase,
- device->options);
+ if (mmio || mmio32)
+ printk(KERN_INFO
+ "Early serial console at MMIO%s 0x%llu (options '%s')\n",
+ mmio32 ? "32" : "",
+ (unsigned long long)port->mapbase,
+ device->options);
+ else
+ printk(KERN_INFO
+ "Early serial console at I/O port 0x%lu (options '%s')\n",
+ port->iobase,
+ device->options);
+
return 0;
}
--
1.7.2
--
