1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Cobalt NOR flash functions 4 * 5 * Copyright 2012-2015 Cisco Systems, Inc. and/or its affiliates. 6 * All rights reserved. 7 */ 8 9 #include <linux/mtd/mtd.h> 10 #include <linux/mtd/map.h> 11 #include <linux/mtd/cfi.h> 12 #include <linux/time.h> 13 14 #include "cobalt-flash.h" 15 16 #define ADRS(offset) (COBALT_BUS_FLASH_BASE + offset) 17 18 static struct map_info cobalt_flash_map = { 19 .name = "cobalt-flash", 20 .bankwidth = 2, /* 16 bits */ 21 .size = 0x4000000, /* 64MB */ 22 .phys = 0, /* offset */ 23 }; 24 25 static map_word flash_read16(struct map_info *map, unsigned long offset) 26 { 27 map_word r; 28 29 r.x[0] = cobalt_bus_read32(map->virt, ADRS(offset)); 30 if (offset & 0x2) 31 r.x[0] >>= 16; 32 else 33 r.x[0] &= 0x0000ffff; 34 35 return r; 36 } 37 38 static void flash_write16(struct map_info *map, const map_word datum, 39 unsigned long offset) 40 { 41 u16 data = (u16)datum.x[0]; 42 43 cobalt_bus_write16(map->virt, ADRS(offset), data); 44 } 45 46 static void flash_copy_from(struct map_info *map, void *to, 47 unsigned long from, ssize_t len) 48 { 49 u32 src = from; 50 u8 *dest = to; 51 u32 data; 52 53 while (len) { 54 data = cobalt_bus_read32(map->virt, ADRS(src)); 55 do { 56 *dest = data >> (8 * (src & 3)); 57 src++; 58 dest++; 59 len--; 60 } while (len && (src % 4)); 61 } 62 } 63 64 static void flash_copy_to(struct map_info *map, unsigned long to, 65 const void *from, ssize_t len) 66 { 67 const u8 *src = from; 68 u32 dest = to; 69 70 pr_info("%s: offset 0x%x: length %zu\n", __func__, dest, len); 71 while (len) { 72 u16 data = 0xffff; 73 74 do { 75 data = *src << (8 * (dest & 1)); 76 src++; 77 dest++; 78 len--; 79 } while (len && (dest % 2)); 80 81 cobalt_bus_write16(map->virt, ADRS(dest - 2), data); 82 } 83 } 84 85 int cobalt_flash_probe(struct cobalt *cobalt) 86 { 87 struct map_info *map = &cobalt_flash_map; 88 struct mtd_info *mtd; 89 90 BUG_ON(!map_bankwidth_supported(map->bankwidth)); 91 map->virt = cobalt->bar1; 92 map->read = flash_read16; 93 map->write = flash_write16; 94 map->copy_from = flash_copy_from; 95 map->copy_to = flash_copy_to; 96 97 mtd = do_map_probe("cfi_probe", map); 98 cobalt->mtd = mtd; 99 if (!mtd) { 100 cobalt_err("Probe CFI flash failed!\n"); 101 return -1; 102 } 103 104 mtd->owner = THIS_MODULE; 105 mtd->dev.parent = &cobalt->pci_dev->dev; 106 mtd_device_register(mtd, NULL, 0); 107 return 0; 108 } 109 110 void cobalt_flash_remove(struct cobalt *cobalt) 111 { 112 if (cobalt->mtd) { 113 mtd_device_unregister(cobalt->mtd); 114 map_destroy(cobalt->mtd); 115 } 116 } 117