linux/arch/arm/mach-ixp4xx/gtwx5715-setup.c
Deepak Saxena 54e269ead6 [ARM] 3226/1: IXP4xx runtime expansion bus window size configuration
Patch from Deepak Saxena

The expansion bus on the IXP46x NPU can be configured for either 32MiB or
16MiB windows and changing the configuration causes the base address for
each chip select for each region to change. Because of this, we cannot
hardcode the physical base as we currently do. This patch checks the
expansion bus configuration registers at runtime to determine the
appropriate window size. Note that this requires that the bootloader
already configured the device sizes appropriately, but I feel that is
valid assumption to make as the bootloader must configure and access
the flash window, the output display (LCD, LEDs, etc) window, and
other expansion bus devices.

Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-05 20:59:29 +00:00

156 lines
3.9 KiB
C

/*
* arch/arm/mach-ixp4xx/gtwx5715-setup.c
*
* Gemtek GTWX5715 (Linksys WRV54G) board settup
*
* Copyright (C) 2004 George T. Joseph
* Derived from Coyote
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include <linux/init.h>
#include <linux/device.h>
#include <linux/serial.h>
#include <linux/tty.h>
#include <linux/serial_8250.h>
#include <linux/slab.h>
#include <asm/types.h>
#include <asm/setup.h>
#include <asm/memory.h>
#include <asm/hardware.h>
#include <asm/irq.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <asm/mach/flash.h>
#include <asm/arch/gtwx5715.h>
/*
* Xscale UART registers are 32 bits wide with only the least
* significant 8 bits having any meaning. From a configuration
* perspective, this means 2 things...
*
* Setting .regshift = 2 so that the standard 16550 registers
* line up on every 4th byte.
*
* Shifting the register start virtual address +3 bytes when
* compiled big-endian. Since register writes are done on a
* single byte basis, if the shift isn't done the driver will
* write the value into the most significant byte of the register,
* which is ignored, instead of the least significant.
*/
#ifdef __ARMEB__
#define REG_OFFSET 3
#else
#define REG_OFFSET 0
#endif
/*
* Only the second or "console" uart is connected on the gtwx5715.
*/
static struct resource gtwx5715_uart_resources[] = {
{
.start = IXP4XX_UART2_BASE_PHYS,
.end = IXP4XX_UART2_BASE_PHYS + 0x0fff,
.flags = IORESOURCE_MEM,
},
{
.start = IRQ_IXP4XX_UART2,
.end = IRQ_IXP4XX_UART2,
.flags = IORESOURCE_IRQ,
},
{ },
};
static struct plat_serial8250_port gtwx5715_uart_platform_data[] = {
{
.mapbase = IXP4XX_UART2_BASE_PHYS,
.membase = (char *)IXP4XX_UART2_BASE_VIRT + REG_OFFSET,
.irq = IRQ_IXP4XX_UART2,
.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = IXP4XX_UART_XTAL,
},
{ },
};
static struct platform_device gtwx5715_uart_device = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM,
.dev = {
.platform_data = gtwx5715_uart_platform_data,
},
.num_resources = 2,
.resource = gtwx5715_uart_resources,
};
static struct flash_platform_data gtwx5715_flash_data = {
.map_name = "cfi_probe",
.width = 2,
};
static struct gtw5715_flash_resource = {
.flags = IORESOURCE_MEM,
}
static struct platform_device gtwx5715_flash = {
.name = "IXP4XX-Flash",
.id = 0,
.dev = {
.platform_data = &gtwx5715_flash_data,
},
.num_resources = 1,
.resource = &gtwx5715_flash_resource,
};
static struct platform_device *gtwx5715_devices[] __initdata = {
&gtwx5715_uart_device,
&gtwx5715_flash,
};
static void __init gtwx5715_init(void)
{
ixp4xx_sys_init();
if (!flash_resource)
printk(KERN_ERR "Could not allocate flash resource\n");
gtwx5715_flash_resource.start = IXP4XX_EXP_BUS_BASE(0);
gtwx5715_flash_resource.end = IXP4XX_EXP_BUS_BASE(0) + SZ_8M - 1;
platform_add_devices(gtwx5715_devices, ARRAY_SIZE(gtwx5715_devices));
}
MACHINE_START(GTWX5715, "Gemtek GTWX5715 (Linksys WRV54G)")
/* Maintainer: George Joseph */
.phys_ram = PHYS_OFFSET,
.phys_io = IXP4XX_UART2_BASE_PHYS,
.io_pg_offst = ((IXP4XX_UART2_BASE_VIRT) >> 18) & 0xfffc,
.map_io = ixp4xx_map_io,
.init_irq = ixp4xx_init_irq,
.timer = &ixp4xx_timer,
.boot_params = 0x0100,
.init_machine = gtwx5715_init,
MACHINE_END