3  * SPI NOR Software Write Protection logic.
10 #include <linux/mtd/spi-nor.h>
14 static u8 spi_nor_get_sr_bp_mask(struct spi_nor *nor)  in spi_nor_get_sr_bp_mask()  argument
18 	if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6)  in spi_nor_get_sr_bp_mask()
21 	if (nor->flags & SNOR_F_HAS_4BIT_BP)  in spi_nor_get_sr_bp_mask()
27 static u8 spi_nor_get_sr_tb_mask(struct spi_nor *nor)  in spi_nor_get_sr_tb_mask()  argument
29 	if (nor->flags & SNOR_F_HAS_SR_TB_BIT6)  in spi_nor_get_sr_tb_mask()
35 static u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor)  in spi_nor_get_min_prot_length_sr()  argument
42 	unsigned int sector_size = nor->info->sector_size ?: SPI_NOR_DEFAULT_SECTOR_SIZE;  in spi_nor_get_min_prot_length_sr()
43 	u64 n_sectors = div_u64(nor->params->size, sector_size);  in spi_nor_get_min_prot_length_sr()
44 	u8 mask = spi_nor_get_sr_bp_mask(nor);  in spi_nor_get_min_prot_length_sr()
56 static void spi_nor_get_locked_range_sr(struct spi_nor *nor, u8 sr, loff_t *ofs,  in spi_nor_get_locked_range_sr()  argument
59 	struct mtd_info *mtd = &nor->mtd;  in spi_nor_get_locked_range_sr()
61 	u8 mask = spi_nor_get_sr_bp_mask(nor);  in spi_nor_get_locked_range_sr()
62 	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);  in spi_nor_get_locked_range_sr()
65 	if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3_BIT6)  in spi_nor_get_locked_range_sr()
77 	min_prot_len = spi_nor_get_min_prot_length_sr(nor);  in spi_nor_get_locked_range_sr()
83 	if (nor->flags & SNOR_F_HAS_SR_TB && sr & tb_mask)  in spi_nor_get_locked_range_sr()
93 static bool spi_nor_check_lock_status_sr(struct spi_nor *nor, loff_t ofs,  in spi_nor_check_lock_status_sr()  argument
102 	spi_nor_get_locked_range_sr(nor, sr, &lock_offs, &lock_len);  in spi_nor_check_lock_status_sr()
115 static bool spi_nor_is_locked_sr(struct spi_nor *nor, loff_t ofs, u64 len, u8 sr)  in spi_nor_is_locked_sr()  argument
117 	return spi_nor_check_lock_status_sr(nor, ofs, len, sr, true);  in spi_nor_is_locked_sr()
120 static bool spi_nor_is_unlocked_sr(struct spi_nor *nor, loff_t ofs, u64 len,  in spi_nor_is_unlocked_sr()  argument
123 	return spi_nor_check_lock_status_sr(nor, ofs, len, sr, false);  in spi_nor_is_unlocked_sr()
159 static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, u64 len)  in spi_nor_sr_lock()  argument
161 	struct mtd_info *mtd = &nor->mtd;  in spi_nor_sr_lock()
164 	u8 mask = spi_nor_get_sr_bp_mask(nor);  in spi_nor_sr_lock()
165 	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);  in spi_nor_sr_lock()
168 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;  in spi_nor_sr_lock()
171 	ret = spi_nor_read_sr(nor, nor->bouncebuf);  in spi_nor_sr_lock()
175 	status_old = nor->bouncebuf[0];  in spi_nor_sr_lock()
178 	if (spi_nor_is_locked_sr(nor, ofs, len, status_old))  in spi_nor_sr_lock()
182 	if (!spi_nor_is_locked_sr(nor, 0, ofs, status_old))  in spi_nor_sr_lock()
186 	if (!spi_nor_is_locked_sr(nor, ofs + len, mtd->size - (ofs + len),  in spi_nor_sr_lock()
205 		min_prot_len = spi_nor_get_min_prot_length_sr(nor);  in spi_nor_sr_lock()
209 		if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)  in spi_nor_sr_lock()
223 	 * Disallow further writes if WP# pin is neither left floating nor  in spi_nor_sr_lock()
227 	if (!(nor->flags & SNOR_F_NO_WP))  in spi_nor_sr_lock()
241 	return spi_nor_write_sr_and_check(nor, status_new);  in spi_nor_sr_lock()
249 static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, u64 len)  in spi_nor_sr_unlock()  argument
251 	struct mtd_info *mtd = &nor->mtd;  in spi_nor_sr_unlock()
254 	u8 mask = spi_nor_get_sr_bp_mask(nor);  in spi_nor_sr_unlock()
255 	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);  in spi_nor_sr_unlock()
258 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;  in spi_nor_sr_unlock()
261 	ret = spi_nor_read_sr(nor, nor->bouncebuf);  in spi_nor_sr_unlock()
265 	status_old = nor->bouncebuf[0];  in spi_nor_sr_unlock()
268 	if (spi_nor_is_unlocked_sr(nor, ofs, len, status_old))  in spi_nor_sr_unlock()
272 	if (!spi_nor_is_unlocked_sr(nor, 0, ofs, status_old))  in spi_nor_sr_unlock()
276 	if (!spi_nor_is_unlocked_sr(nor, ofs + len, mtd->size - (ofs + len),  in spi_nor_sr_unlock()
295 		min_prot_len = spi_nor_get_min_prot_length_sr(nor);  in spi_nor_sr_unlock()
299 		if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)  in spi_nor_sr_unlock()
324 	return spi_nor_write_sr_and_check(nor, status_new);  in spi_nor_sr_unlock()
334 static int spi_nor_sr_is_locked(struct spi_nor *nor, loff_t ofs, u64 len)  in spi_nor_sr_is_locked()  argument
338 	ret = spi_nor_read_sr(nor, nor->bouncebuf);  in spi_nor_sr_is_locked()
342 	return spi_nor_is_locked_sr(nor, ofs, len, nor->bouncebuf[0]);  in spi_nor_sr_is_locked()
351 void spi_nor_init_default_locking_ops(struct spi_nor *nor)  in spi_nor_init_default_locking_ops()  argument
353 	nor->params->locking_ops = &spi_nor_sr_locking_ops;  in spi_nor_init_default_locking_ops()
358 	struct spi_nor *nor = mtd_to_spi_nor(mtd);  in spi_nor_lock()  local
361 	ret = spi_nor_prep_and_lock(nor);  in spi_nor_lock()
365 	ret = nor->params->locking_ops->lock(nor, ofs, len);  in spi_nor_lock()
367 	spi_nor_unlock_and_unprep(nor);  in spi_nor_lock()
373 	struct spi_nor *nor = mtd_to_spi_nor(mtd);  in spi_nor_unlock()  local
376 	ret = spi_nor_prep_and_lock(nor);  in spi_nor_unlock()
380 	ret = nor->params->locking_ops->unlock(nor, ofs, len);  in spi_nor_unlock()
382 	spi_nor_unlock_and_unprep(nor);  in spi_nor_unlock()
388 	struct spi_nor *nor = mtd_to_spi_nor(mtd);  in spi_nor_is_locked()  local
391 	ret = spi_nor_prep_and_lock(nor);  in spi_nor_is_locked()
395 	ret = nor->params->locking_ops->is_locked(nor, ofs, len);  in spi_nor_is_locked()
397 	spi_nor_unlock_and_unprep(nor);  in spi_nor_is_locked()
403  * @nor:	pointer to a 'struct spi_nor'.
405  * Some SPI NOR flashes are write protected by default after a power-on reset
413 void spi_nor_try_unlock_all(struct spi_nor *nor)  in spi_nor_try_unlock_all()  argument
417 	if (!(nor->flags & SNOR_F_HAS_LOCK))  in spi_nor_try_unlock_all()
420 	dev_dbg(nor->dev, "Unprotecting entire flash array\n");  in spi_nor_try_unlock_all()
422 	ret = spi_nor_unlock(&nor->mtd, 0, nor->params->size);  in spi_nor_try_unlock_all()
424 		dev_dbg(nor->dev, "Failed to unlock the entire flash memory array\n");  in spi_nor_try_unlock_all()
427 void spi_nor_set_mtd_locking_ops(struct spi_nor *nor)  in spi_nor_set_mtd_locking_ops()  argument
429 	struct mtd_info *mtd = &nor->mtd;  in spi_nor_set_mtd_locking_ops()
431 	if (!nor->params->locking_ops)  in spi_nor_set_mtd_locking_ops()