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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef FWH_LOCK_H3#define FWH_LOCK_H4 5 6enum fwh_lock_state {7 FWH_UNLOCKED = 0,8 FWH_DENY_WRITE = 1,9 FWH_IMMUTABLE = 2,10 FWH_DENY_READ = 4,11};12 13struct fwh_xxlock_thunk {14 enum fwh_lock_state val;15 flstate_t state;16};17 18 19#define FWH_XXLOCK_ONEBLOCK_LOCK ((struct fwh_xxlock_thunk){ FWH_DENY_WRITE, FL_LOCKING})20#define FWH_XXLOCK_ONEBLOCK_UNLOCK ((struct fwh_xxlock_thunk){ FWH_UNLOCKED, FL_UNLOCKING})21 22/*23 * This locking/unlock is specific to firmware hub parts. Only one24 * is known that supports the Intel command set. Firmware25 * hub parts cannot be interleaved as they are on the LPC bus26 * so this code has not been tested with interleaved chips,27 * and will likely fail in that context.28 */29static int fwh_xxlock_oneblock(struct map_info *map, struct flchip *chip,30 unsigned long adr, int len, void *thunk)31{32 struct cfi_private *cfi = map->fldrv_priv;33 struct fwh_xxlock_thunk *xxlt = (struct fwh_xxlock_thunk *)thunk;34 int ret;35 36 /* Refuse the operation if the we cannot look behind the chip */37 if (chip->start < 0x400000) {38 pr_debug( "MTD %s(): chip->start: %lx wanted >= 0x400000\n",39 __func__, chip->start );40 return -EIO;41 }42 /*43 * lock block registers:44 * - on 64k boundariesand45 * - bit 1 set high46 * - block lock registers are 4MiB lower - overflow subtract (danger)47 *48 * The address manipulation is first done on the logical address49 * which is 0 at the start of the chip, and then the offset of50 * the individual chip is addted to it. Any other order a weird51 * map offset could cause problems.52 */53 adr = (adr & ~0xffffUL) | 0x2;54 adr += chip->start - 0x400000;55 56 /*57 * This is easy because these are writes to registers and not writes58 * to flash memory - that means that we don't have to check status59 * and timeout.60 */61 mutex_lock(&chip->mutex);62 ret = get_chip(map, chip, adr, FL_LOCKING);63 if (ret) {64 mutex_unlock(&chip->mutex);65 return ret;66 }67 68 chip->oldstate = chip->state;69 chip->state = xxlt->state;70 map_write(map, CMD(xxlt->val), adr);71 72 /* Done and happy. */73 chip->state = chip->oldstate;74 put_chip(map, chip, adr);75 mutex_unlock(&chip->mutex);76 return 0;77}78 79 80static int fwh_lock_varsize(struct mtd_info *mtd, loff_t ofs, uint64_t len)81{82 int ret;83 84 ret = cfi_varsize_frob(mtd, fwh_xxlock_oneblock, ofs, len,85 (void *)&FWH_XXLOCK_ONEBLOCK_LOCK);86 87 return ret;88}89 90 91static int fwh_unlock_varsize(struct mtd_info *mtd, loff_t ofs, uint64_t len)92{93 int ret;94 95 ret = cfi_varsize_frob(mtd, fwh_xxlock_oneblock, ofs, len,96 (void *)&FWH_XXLOCK_ONEBLOCK_UNLOCK);97 98 return ret;99}100 101static void fixup_use_fwh_lock(struct mtd_info *mtd)102{103 printk(KERN_NOTICE "using fwh lock/unlock method\n");104 /* Setup for the chips with the fwh lock method */105 mtd->_lock = fwh_lock_varsize;106 mtd->_unlock = fwh_unlock_varsize;107}108#endif /* FWH_LOCK_H */109