1 // SPDX-License-Identifier: GPL-2.0-only
3  * MTD map driver for BIOS Flash on Intel SCB2 boards
20  * * D8-D15 ignored
25  * logical address 0 hit higher-address sections of the chip, not physical 0.
29  * This driver assumes the chip is not write-protected by an external signal.
33  * updates for this board include 10 related (*.bio - &.bi9) binary files and
40  * offset 0x00000 to 0x4ffff (320k):  unknown - SCSI BIOS, etc?
54 #include <linux/mtd/cfi.h>
66 	.name =      "SCB2 BIOS Flash",
76 	struct map_info *map = mtd->priv;  in scb2_fixup_mtd()
77 	struct cfi_private *cfi = map->fldrv_priv;  in scb2_fixup_mtd()  local
80 	if (cfi->cfiq->InterfaceDesc != CFI_INTERFACE_X16_ASYNC) {  in scb2_fixup_mtd()
82 		    cfi->cfiq->InterfaceDesc);  in scb2_fixup_mtd()
83 		return -1;  in scb2_fixup_mtd()
88 	/* the chip is sometimes bigger than the map - what a waste */  in scb2_fixup_mtd()
89 	mtd->size = map->size;  in scb2_fixup_mtd()
93 	 * wired up - D8-D15 are tossed away.  We read linear bytes,  in scb2_fixup_mtd()
94 	 * but in reality we are getting 1/2 of each 16-bit read,  in scb2_fixup_mtd()
95 	 * which LOOKS linear to us.  Because CFI code accounts for  in scb2_fixup_mtd()
101 	 *   -- the problem is that addresses are 16-bit addressable  in scb2_fixup_mtd()
102 	 *   -- we end up erasing every-other block  in scb2_fixup_mtd()
104 	mtd->erasesize /= 2;  in scb2_fixup_mtd()
105 	for (i = 0; i < mtd->numeraseregions; i++) {  in scb2_fixup_mtd()
106 		struct mtd_erase_region_info *region = &mtd->eraseregions[i];  in scb2_fixup_mtd()
107 		region->erasesize /= 2;  in scb2_fixup_mtd()
113 	 * the chip, so all our erase-region info is wrong.  Start cutting from  in scb2_fixup_mtd()
116 	for (i = 0; !done && i < mtd->numeraseregions; i++) {  in scb2_fixup_mtd()
117 		struct mtd_erase_region_info *region = &mtd->eraseregions[i];  in scb2_fixup_mtd()
119 		if (region->numblocks * region->erasesize > mtd->size) {  in scb2_fixup_mtd()
120 			region->numblocks = ((unsigned long)mtd->size /  in scb2_fixup_mtd()
121 						region->erasesize);  in scb2_fixup_mtd()
124 			region->numblocks = 0;  in scb2_fixup_mtd()
126 		region->offset = 0;  in scb2_fixup_mtd()
140 	/* enable decoding of the flash region in the south bridge */  in scb2_flash_probe()
146 		 * The BIOS seems to mark the flash region as 'reserved'  in scb2_flash_probe()
150 		    ": warning - can't reserve rom window, continuing\n");  in scb2_flash_probe()
160 		return -ENOMEM;  in scb2_flash_probe()
173 		printk(KERN_ERR MODNAME ": flash probe failed!\n");  in scb2_flash_probe()
177 		return -ENODEV;  in scb2_flash_probe()
180 	scb2_mtd->owner = THIS_MODULE;  in scb2_flash_probe()
187 		return -ENODEV;  in scb2_flash_probe()
191 	       (unsigned long long)scb2_mtd->size,  in scb2_flash_probe()
192 	       (unsigned long long)(SCB2_WINDOW - scb2_mtd->size));  in scb2_flash_probe()
204 	/* disable flash writes */  in scb2_flash_remove()
205 	mtd_lock(scb2_mtd, 0, scb2_mtd->size);  in scb2_flash_remove()
228 	.name =     "Intel SCB2 BIOS Flash",
238 MODULE_DESCRIPTION("MTD map driver for Intel SCB2 BIOS Flash");