Hi Ricardo,
I implemented serial platform driver taking as model serial.c from
cavium-octeon.
Here is my code:
/*
* This file is subject to the terms and conditions of the GNU General
Public
* License. See the file "COPYING" in the main directory of this
archive
* for more details.
*
* Copyright (C) 2004-2007 Cavium Networks
*/
#include <linux/console.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/serial.h>
#include <linux/serial_8250.h>
#include <linux/serial_reg.h>
#include <linux/tty.h>
#include <asm/time.h>
#include <sys_defs.h>
#ifdef CONFIG_GDB_CONSOLE
#define DEBUG_UART 0
#else
#define DEBUG_UART 1
#endif
unsigned int gd_serial_in(struct uart_port *up, int offset)
{
int rv = inl((unsigned int)(up->membase + (offset << 2)));
if (offset == UART_IIR && (rv & 0xf) == 7) {
/* Busy interrupt, read the USR (39) and try again. */
inl((unsigned int)(up->membase + (39 << 2)));
rv = inl((unsigned int)(up->membase + (offset << 2)));
}
return rv;
}
void gd_serial_out(struct uart_port *up, int offset, int value)
{
outl( value & 0xff, (unsigned int)(up->membase + (offset <<
2)));
}
/*
* Allocated in .bss, so it is all zeroed.
*/
#define GD_MAX_UARTS 1
static struct plat_serial8250_port gd_uart8250_data[GD_MAX_UARTS + 1];
static struct platform_device gd_uart8250_device = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM,
.dev = {
.platform_data = gd_uart8250_data,
},
};
static void __init gd_uart_set_common(struct plat_serial8250_port *p)
{
p->flags = ASYNC_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
p->type = PORT_GD;
p->iotype = UPIO_MEM;
p->regshift = 2; /* I/O addresses are every 4 bytes */
p->uartclk = UART_CLK;
p->serial_in = gd_serial_in;
p->serial_out = gd_serial_out;
}
static int __init gd_serial_init(void)
{
int enable_uart0;
struct plat_serial8250_port *p;
enable_uart0 = 1;
p = gd_uart8250_data;
if (enable_uart0) {
/* Add a ttyS device for hardware uart 0 */
gd_uart_set_common(p);
p->membase = (void *) offMCU_UART_THR_OR_RBR_OR_DLL;
p->mapbase = offMCU_UART_THR_OR_RBR_OR_DLL;
p->irq = MIPSCPU_INT_UART;
p++;
}
return platform_device_register(&gd_uart8250_device);
}
device_initcall(gd_serial_init);
------------------------------------------------------------------------
-----------------------
Thanks,
Andrei
-----Original Message-----
From: mendoza.ricardo@xxxxxxxxx [mailto:mendoza.ricardo@xxxxxxxxx] On
Behalf Of Ricardo Mendoza
Sent: Thursday, November 18, 2010 4:21 PM
To: Ardelean, Andrei
Cc: linux-mips@xxxxxxxxxxxxxx
Subject: Re: The new "real" console doesn't display printk() messages
like "early" console!
On Thu, Nov 18, 2010 at 8:04 PM, Ardelean, Andrei
<Andrei.Ardelean@xxxxxxx> wrote:
> I specified that when the bootloader calls the kernel and I did see
that
> the baudrate is correct and I have some messages but when the system
is
> crashing I cannot see printk messages. For instance, I step with JTAG
> and I can see that printk(KERNEL_WARNING "unable to open initial
> console") is called but on the terminal I cannot see the message. The
> same, die() is called but there is no messages on UART terminal.
You say you are porting to a new system, perhaps you didn't set up
your 8250 platform device. Most boards will have an example for you in
the tree.
Ricardo
