linux_dsm_epyc7002/arch/mips/cavium-octeon/flash_setup.c
David Daney 8c1e6b14e2 MIPS: OCTEON: Protect accesses to bootbus flash with octeon_bootbus_sem.
Without this, we get bus errors.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Aleksey Makarov <aleksey.makarov@auriga.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9460/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:43 +02:00

113 lines
3.0 KiB
C

/*
* Octeon Bootbus flash setup
*
* 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) 2007, 2008 Cavium Networks
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/semaphore.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <asm/octeon/octeon.h>
static struct map_info flash_map;
static struct mtd_info *mymtd;
static const char *part_probe_types[] = {
"cmdlinepart",
#ifdef CONFIG_MTD_REDBOOT_PARTS
"RedBoot",
#endif
NULL
};
static map_word octeon_flash_map_read(struct map_info *map, unsigned long ofs)
{
map_word r;
down(&octeon_bootbus_sem);
r = inline_map_read(map, ofs);
up(&octeon_bootbus_sem);
return r;
}
static void octeon_flash_map_write(struct map_info *map, const map_word datum,
unsigned long ofs)
{
down(&octeon_bootbus_sem);
inline_map_write(map, datum, ofs);
up(&octeon_bootbus_sem);
}
static void octeon_flash_map_copy_from(struct map_info *map, void *to,
unsigned long from, ssize_t len)
{
down(&octeon_bootbus_sem);
inline_map_copy_from(map, to, from, len);
up(&octeon_bootbus_sem);
}
static void octeon_flash_map_copy_to(struct map_info *map, unsigned long to,
const void *from, ssize_t len)
{
down(&octeon_bootbus_sem);
inline_map_copy_to(map, to, from, len);
up(&octeon_bootbus_sem);
}
/**
* Module/ driver initialization.
*
* Returns Zero on success
*/
static int __init flash_init(void)
{
/*
* Read the bootbus region 0 setup to determine the base
* address of the flash.
*/
union cvmx_mio_boot_reg_cfgx region_cfg;
region_cfg.u64 = cvmx_read_csr(CVMX_MIO_BOOT_REG_CFGX(0));
if (region_cfg.s.en) {
/*
* The bootloader always takes the flash and sets its
* address so the entire flash fits below
* 0x1fc00000. This way the flash aliases to
* 0x1fc00000 for booting. Software can access the
* full flash at the true address, while core boot can
* access 4MB.
*/
/* Use this name so old part lines work */
flash_map.name = "phys_mapped_flash";
flash_map.phys = region_cfg.s.base << 16;
flash_map.size = 0x1fc00000 - flash_map.phys;
/* 8-bit bus (0 + 1) or 16-bit bus (1 + 1) */
flash_map.bankwidth = region_cfg.s.width + 1;
flash_map.virt = ioremap(flash_map.phys, flash_map.size);
pr_notice("Bootbus flash: Setting flash for %luMB flash at "
"0x%08llx\n", flash_map.size >> 20, flash_map.phys);
WARN_ON(!map_bankwidth_supported(flash_map.bankwidth));
flash_map.read = octeon_flash_map_read;
flash_map.write = octeon_flash_map_write;
flash_map.copy_from = octeon_flash_map_copy_from;
flash_map.copy_to = octeon_flash_map_copy_to;
mymtd = do_map_probe("cfi_probe", &flash_map);
if (mymtd) {
mymtd->owner = THIS_MODULE;
mtd_device_parse_register(mymtd, part_probe_types,
NULL, NULL, 0);
} else {
pr_err("Failed to register MTD device for flash\n");
}
}
return 0;
}
late_initcall(flash_init);