remarkable-linux/arch/arm/mach-sa1100/pleb.c
Russell King 2fb04fdf30 net: smc91x: fix SMC accesses
Commit b70661c708 ("net: smc91x: use run-time configuration on all ARM
machines") broke some ARM platforms through several mistakes.  Firstly,
the access size must correspond to the following rule:

(a) at least one of 16-bit or 8-bit access size must be supported
(b) 32-bit accesses are optional, and may be enabled in addition to
    the above.

Secondly, it provides no emulation of 16-bit accesses, instead blindly
making 16-bit accesses even when the platform specifies that only 8-bit
is supported.

Reorganise smc91x.h so we can make use of the existing 16-bit access
emulation already provided - if 16-bit accesses are supported, use
16-bit accesses directly, otherwise if 8-bit accesses are supported,
use the provided 16-bit access emulation.  If neither, BUG().  This
exactly reflects the driver behaviour prior to the commit being fixed.

Since the conversion incorrectly cut down the available access sizes on
several platforms, we also need to go through every platform and fix up
the overly-restrictive access size: Arnd assumed that if a platform can
perform 32-bit, 16-bit and 8-bit accesses, then only a 32-bit access
size needed to be specified - not so, all available access sizes must
be specified.

This likely fixes some performance regressions in doing this: if a
platform does not support 8-bit accesses, 8-bit accesses have been
emulated by performing a 16-bit read-modify-write access.

Tested on the Intel Assabet/Neponset platform, which supports only 8-bit
accesses, which was broken by the original commit.

Fixes: b70661c708 ("net: smc91x: use run-time configuration on all ARM machines")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-28 23:44:55 -04:00

148 lines
3.1 KiB
C

/*
* linux/arch/arm/mach-sa1100/pleb.c
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/platform_data/sa11x0-serial.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/mtd/partitions.h>
#include <linux/smc91x.h>
#include <mach/hardware.h>
#include <asm/setup.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <asm/mach/flash.h>
#include <mach/irqs.h>
#include "generic.h"
/*
* Ethernet IRQ mappings
*/
#define PLEB_ETH0_P (0x20000300) /* Ethernet 0 in PCMCIA0 IO */
#define PLEB_ETH0_V (0xf6000300)
#define GPIO_ETH0_IRQ GPIO_GPIO(21)
#define GPIO_ETH0_EN GPIO_GPIO(26)
#define IRQ_GPIO_ETH0_IRQ IRQ_GPIO21
static struct resource smc91x_resources[] = {
[0] = DEFINE_RES_MEM(PLEB_ETH0_P, 0x04000000),
#if 0 /* Autoprobe instead, to get rising/falling edge characteristic right */
[1] = DEFINE_RES_IRQ(IRQ_GPIO_ETH0_IRQ),
#endif
};
static struct smc91x_platdata smc91x_platdata = {
.flags = SMC91X_USE_16BIT | SMC91X_USE_8BIT | SMC91X_NOWAIT,
};
static struct platform_device smc91x_device = {
.name = "smc91x",
.id = 0,
.num_resources = ARRAY_SIZE(smc91x_resources),
.resource = smc91x_resources,
.dev = {
.platform_data = &smc91x_platdata,
},
};
static struct platform_device *devices[] __initdata = {
&smc91x_device,
};
/*
* Pleb's memory map
* has flash memory (typically 4 or 8 meg) selected by
* the two SA1100 lowest chip select outputs.
*/
static struct resource pleb_flash_resources[] = {
[0] = DEFINE_RES_MEM(SA1100_CS0_PHYS, SZ_8M),
[1] = DEFINE_RES_MEM(SA1100_CS1_PHYS, SZ_8M),
};
static struct mtd_partition pleb_partitions[] = {
{
.name = "blob",
.offset = 0,
.size = 0x00020000,
}, {
.name = "kernel",
.offset = MTDPART_OFS_APPEND,
.size = 0x000e0000,
}, {
.name = "rootfs",
.offset = MTDPART_OFS_APPEND,
.size = 0x00300000,
}
};
static struct flash_platform_data pleb_flash_data = {
.map_name = "cfi_probe",
.parts = pleb_partitions,
.nr_parts = ARRAY_SIZE(pleb_partitions),
};
static void __init pleb_init(void)
{
sa11x0_register_mtd(&pleb_flash_data, pleb_flash_resources,
ARRAY_SIZE(pleb_flash_resources));
platform_add_devices(devices, ARRAY_SIZE(devices));
}
static void __init pleb_map_io(void)
{
sa1100_map_io();
sa1100_register_uart(0, 3);
sa1100_register_uart(1, 1);
GAFR |= (GPIO_UART_TXD | GPIO_UART_RXD);
GPDR |= GPIO_UART_TXD;
GPDR &= ~GPIO_UART_RXD;
PPAR |= PPAR_UPR;
/*
* Fix expansion memory timing for network card
*/
MECR = ((2<<10) | (2<<5) | (2<<0));
/*
* Enable the SMC ethernet controller
*/
GPDR |= GPIO_ETH0_EN; /* set to output */
GPCR = GPIO_ETH0_EN; /* clear MCLK (enable smc) */
GPDR &= ~GPIO_ETH0_IRQ;
irq_set_irq_type(GPIO_ETH0_IRQ, IRQ_TYPE_EDGE_FALLING);
}
MACHINE_START(PLEB, "PLEB")
.map_io = pleb_map_io,
.nr_irqs = SA1100_NR_IRQS,
.init_irq = sa1100_init_irq,
.init_time = sa1100_timer_init,
.init_machine = pleb_init,
.init_late = sa11x0_init_late,
.restart = sa11x0_restart,
MACHINE_END