1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Routines common to all CFI-type probes. 4 * (C) 2001-2003 Red Hat, Inc. 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/slab.h> 9 #include <linux/module.h> 10 #include <linux/mtd/mtd.h> 11 #include <linux/mtd/map.h> 12 #include <linux/mtd/cfi.h> 13 #include <linux/mtd/gen_probe.h> 14 15 static struct mtd_info *check_cmd_set(struct map_info *, int); 16 static struct cfi_private *genprobe_ident_chips(struct map_info *map, 17 struct chip_probe *cp); 18 static int genprobe_new_chip(struct map_info *map, struct chip_probe *cp, 19 struct cfi_private *cfi); 20 21 struct mtd_info *mtd_do_chip_probe(struct map_info *map, struct chip_probe *cp) 22 { 23 struct mtd_info *mtd; 24 struct cfi_private *cfi; 25 26 /* First probe the map to see if we have CFI stuff there. */ 27 cfi = genprobe_ident_chips(map, cp); 28 29 if (!cfi) 30 return NULL; 31 32 map->fldrv_priv = cfi; 33 /* OK we liked it. Now find a driver for the command set it talks */ 34 35 mtd = check_cmd_set(map, 1); /* First the primary cmdset */ 36 if (!mtd) 37 mtd = check_cmd_set(map, 0); /* Then the secondary */ 38 39 if (mtd) { 40 if (mtd->size > map->size) { 41 printk(KERN_WARNING "Reducing visibility of %ldKiB chip to %ldKiB\n", 42 (unsigned long)mtd->size >> 10, 43 (unsigned long)map->size >> 10); 44 mtd->size = map->size; 45 } 46 return mtd; 47 } 48 49 printk(KERN_WARNING"gen_probe: No supported Vendor Command Set found\n"); 50 51 kfree(cfi->cfiq); 52 kfree(cfi); 53 map->fldrv_priv = NULL; 54 return NULL; 55 } 56 EXPORT_SYMBOL(mtd_do_chip_probe); 57 58 59 static struct cfi_private *genprobe_ident_chips(struct map_info *map, struct chip_probe *cp) 60 { 61 struct cfi_private cfi; 62 struct cfi_private *retcfi; 63 unsigned long *chip_map; 64 int max_chips; 65 int i, j; 66 67 memset(&cfi, 0, sizeof(cfi)); 68 69 /* Call the probetype-specific code with all permutations of 70 interleave and device type, etc. */ 71 if (!genprobe_new_chip(map, cp, &cfi)) { 72 /* The probe didn't like it */ 73 pr_debug("%s: Found no %s device at location zero\n", 74 cp->name, map->name); 75 return NULL; 76 } 77 78 #if 0 /* Let the CFI probe routine do this sanity check. The Intel and AMD 79 probe routines won't ever return a broken CFI structure anyway, 80 because they make them up themselves. 81 */ 82 if (cfi.cfiq->NumEraseRegions == 0) { 83 printk(KERN_WARNING "Number of erase regions is zero\n"); 84 kfree(cfi.cfiq); 85 return NULL; 86 } 87 #endif 88 cfi.chipshift = cfi.cfiq->DevSize; 89 90 if (cfi_interleave_is_1(&cfi)) { 91 ; 92 } else if (cfi_interleave_is_2(&cfi)) { 93 cfi.chipshift++; 94 } else if (cfi_interleave_is_4((&cfi))) { 95 cfi.chipshift += 2; 96 } else if (cfi_interleave_is_8(&cfi)) { 97 cfi.chipshift += 3; 98 } else { 99 BUG(); 100 } 101 102 cfi.numchips = 1; 103 104 /* 105 * Allocate memory for bitmap of valid chips. 106 * Align bitmap storage size to full byte. 107 */ 108 max_chips = map->size >> cfi.chipshift; 109 if (!max_chips) { 110 printk(KERN_WARNING "NOR chip too large to fit in mapping. Attempting to cope...\n"); 111 max_chips = 1; 112 } 113 114 chip_map = bitmap_zalloc(max_chips, GFP_KERNEL); 115 if (!chip_map) { 116 kfree(cfi.cfiq); 117 return NULL; 118 } 119 120 set_bit(0, chip_map); /* Mark first chip valid */ 121 122 /* 123 * Now probe for other chips, checking sensibly for aliases while 124 * we're at it. The new_chip probe above should have let the first 125 * chip in read mode. 126 */ 127 128 for (i = 1; i < max_chips; i++) { 129 cp->probe_chip(map, i << cfi.chipshift, chip_map, &cfi); 130 } 131 132 /* 133 * Now allocate the space for the structures we need to return to 134 * our caller, and copy the appropriate data into them. 135 */ 136 137 retcfi = kmalloc(struct_size(retcfi, chips, cfi.numchips), GFP_KERNEL); 138 139 if (!retcfi) { 140 kfree(cfi.cfiq); 141 bitmap_free(chip_map); 142 return NULL; 143 } 144 145 memcpy(retcfi, &cfi, sizeof(cfi)); 146 memset(&retcfi->chips[0], 0, sizeof(struct flchip) * cfi.numchips); 147 148 for (i = 0, j = 0; (j < cfi.numchips) && (i < max_chips); i++) { 149 if(test_bit(i, chip_map)) { 150 struct flchip *pchip = &retcfi->chips[j++]; 151 152 pchip->start = (i << cfi.chipshift); 153 pchip->state = FL_READY; 154 init_waitqueue_head(&pchip->wq); 155 mutex_init(&pchip->mutex); 156 } 157 } 158 159 bitmap_free(chip_map); 160 return retcfi; 161 } 162 163 164 static int genprobe_new_chip(struct map_info *map, struct chip_probe *cp, 165 struct cfi_private *cfi) 166 { 167 int min_chips = (map_bankwidth(map)/4?:1); /* At most 4-bytes wide. */ 168 int max_chips = map_bankwidth(map); /* And minimum 1 */ 169 int nr_chips, type; 170 171 for (nr_chips = max_chips; nr_chips >= min_chips; nr_chips >>= 1) { 172 173 if (!cfi_interleave_supported(nr_chips)) 174 continue; 175 176 cfi->interleave = nr_chips; 177 178 /* Minimum device size. Don't look for one 8-bit device 179 in a 16-bit bus, etc. */ 180 type = map_bankwidth(map) / nr_chips; 181 182 for (; type <= CFI_DEVICETYPE_X32; type<<=1) { 183 cfi->device_type = type; 184 185 if (cp->probe_chip(map, 0, NULL, cfi)) 186 return 1; 187 } 188 } 189 return 0; 190 } 191 192 typedef struct mtd_info *cfi_cmdset_fn_t(struct map_info *, int); 193 194 extern cfi_cmdset_fn_t cfi_cmdset_0001; 195 extern cfi_cmdset_fn_t cfi_cmdset_0002; 196 extern cfi_cmdset_fn_t cfi_cmdset_0020; 197 198 static inline struct mtd_info *cfi_cmdset_unknown(struct map_info *map, 199 int primary) 200 { 201 struct cfi_private *cfi = map->fldrv_priv; 202 __u16 type = primary?cfi->cfiq->P_ID:cfi->cfiq->A_ID; 203 #ifdef CONFIG_MODULES 204 cfi_cmdset_fn_t *probe_function; 205 char *probename; 206 207 probename = kasprintf(GFP_KERNEL, "cfi_cmdset_%4.4X", type); 208 if (!probename) 209 return NULL; 210 211 probe_function = __symbol_get(probename); 212 if (!probe_function) { 213 request_module("cfi_cmdset_%4.4X", type); 214 probe_function = __symbol_get(probename); 215 } 216 kfree(probename); 217 218 if (probe_function) { 219 struct mtd_info *mtd; 220 221 mtd = (*probe_function)(map, primary); 222 /* If it was happy, it'll have increased its own use count */ 223 symbol_put_addr(probe_function); 224 return mtd; 225 } 226 #endif 227 printk(KERN_NOTICE "Support for command set %04X not present\n", type); 228 229 return NULL; 230 } 231 232 static struct mtd_info *check_cmd_set(struct map_info *map, int primary) 233 { 234 struct cfi_private *cfi = map->fldrv_priv; 235 __u16 type = primary?cfi->cfiq->P_ID:cfi->cfiq->A_ID; 236 237 if (type == P_ID_NONE || type == P_ID_RESERVED) 238 return NULL; 239 240 switch(type){ 241 /* We need these for the !CONFIG_MODULES case, 242 because symbol_get() doesn't work there */ 243 #ifdef CONFIG_MTD_CFI_INTELEXT 244 case P_ID_INTEL_EXT: 245 case P_ID_INTEL_STD: 246 case P_ID_INTEL_PERFORMANCE: 247 return cfi_cmdset_0001(map, primary); 248 #endif 249 #ifdef CONFIG_MTD_CFI_AMDSTD 250 case P_ID_AMD_STD: 251 case P_ID_SST_OLD: 252 case P_ID_WINBOND: 253 return cfi_cmdset_0002(map, primary); 254 #endif 255 #ifdef CONFIG_MTD_CFI_STAA 256 case P_ID_ST_ADV: 257 return cfi_cmdset_0020(map, primary); 258 #endif 259 default: 260 return cfi_cmdset_unknown(map, primary); 261 } 262 } 263 264 MODULE_LICENSE("GPL"); 265 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); 266 MODULE_DESCRIPTION("Helper routines for flash chip probe code"); 267