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1// SPDX-License-Identifier: GPL-2.02/*3 * tsunami_flash.c4 *5 * flash chip on alpha ds10...6 */7#include <asm/io.h>8#include <asm/core_tsunami.h>9#include <linux/init.h>10#include <linux/mtd/map.h>11#include <linux/mtd/mtd.h>12 13#define FLASH_ENABLE_PORT 0x00C0000114#define FLASH_ENABLE_BYTE 0x0115#define FLASH_DISABLE_BYTE 0x0016 17#define MAX_TIG_FLASH_SIZE (12*1024*1024)18static inline map_word tsunami_flash_read8(struct map_info *map, unsigned long offset)19{20 map_word val;21 val.x[0] = tsunami_tig_readb(offset);22 return val;23}24 25static void tsunami_flash_write8(struct map_info *map, map_word value, unsigned long offset)26{27 tsunami_tig_writeb(value.x[0], offset);28}29 30static void tsunami_flash_copy_from(31 struct map_info *map, void *addr, unsigned long offset, ssize_t len)32{33 unsigned char *dest;34 dest = addr;35 while(len && (offset < MAX_TIG_FLASH_SIZE)) {36 *dest = tsunami_tig_readb(offset);37 offset++;38 dest++;39 len--;40 }41}42 43static void tsunami_flash_copy_to(44 struct map_info *map, unsigned long offset,45 const void *addr, ssize_t len)46{47 const unsigned char *src;48 src = addr;49 while(len && (offset < MAX_TIG_FLASH_SIZE)) {50 tsunami_tig_writeb(*src, offset);51 offset++;52 src++;53 len--;54 }55}56 57/*58 * Deliberately don't provide operations wider than 8 bits. I don't59 * have then and it scares me to think how you could mess up if60 * you tried to use them. Buswidth is correctly so I'm safe.61 */62static struct map_info tsunami_flash_map = {63 .name = "flash chip on the Tsunami TIG bus",64 .size = MAX_TIG_FLASH_SIZE,65 .phys = NO_XIP,66 .bankwidth = 1,67 .read = tsunami_flash_read8,68 .copy_from = tsunami_flash_copy_from,69 .write = tsunami_flash_write8,70 .copy_to = tsunami_flash_copy_to,71};72 73static struct mtd_info *tsunami_flash_mtd;74 75static void __exit cleanup_tsunami_flash(void)76{77 struct mtd_info *mtd;78 mtd = tsunami_flash_mtd;79 if (mtd) {80 mtd_device_unregister(mtd);81 map_destroy(mtd);82 }83 tsunami_flash_mtd = 0;84}85 86static const char * const rom_probe_types[] = {87 "cfi_probe", "jedec_probe", "map_rom", NULL };88 89static int __init init_tsunami_flash(void)90{91 const char * const *type;92 93 tsunami_tig_writeb(FLASH_ENABLE_BYTE, FLASH_ENABLE_PORT);94 95 tsunami_flash_mtd = 0;96 type = rom_probe_types;97 for(; !tsunami_flash_mtd && *type; type++) {98 tsunami_flash_mtd = do_map_probe(*type, &tsunami_flash_map);99 }100 if (tsunami_flash_mtd) {101 tsunami_flash_mtd->owner = THIS_MODULE;102 mtd_device_register(tsunami_flash_mtd, NULL, 0);103 return 0;104 }105 return -ENXIO;106}107 108module_init(init_tsunami_flash);109module_exit(cleanup_tsunami_flash);110