Linux-mtd Archive on lore.kernel.org
 help / color / Atom feed
From: <Tudor.Ambarus@microchip.com>
To: <js07.lee@samsung.com>, <michael@walle.cc>, <vigneshr@ti.com>
Cc: linux-mtd@lists.infradead.org, Tudor.Ambarus@microchip.com
Subject: [PATCH v3 4/5] mtd: spi-nor: Add 4bit SR block protection support
Date: Mon, 23 Mar 2020 09:24:35 +0000
Message-ID: <20200323092430.1466234-5-tudor.ambarus@microchip.com> (raw)
In-Reply-To: <20200323092430.1466234-1-tudor.ambarus@microchip.com>

From: Jungseung Lee <js07.lee@samsung.com>

Currently, we are supporting block protection only for flash chips with
3 block protection bits (BP0-2) in the SR register.

Enable block protection support for flashes with 4 block protection bits
(BP0-3).

Add a flash_info flag for flashes that describe 4 block protection bits.
Add another flash_info flag for flashes in which BP3 bit is not adjacent
to the BP0-2 bits.

Signed-off-by: Jungseung Lee <js07.lee@samsung.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Tested-by: Michael Walle <michael@walle.cc>
[ta:
- introduce spi_nor_get_sr_bp_mask(), spi_nor_get_sr_tb_mask()
- drop Micron n25q512ax3 / BP0-3) boilerplate description
- be explicit in spi_nor_get_locked_range_sr aboyt SR_BP3 as Michael
suggested,
- amend commit description]
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 drivers/mtd/spi-nor/core.c  | 66 +++++++++++++++++++++++++++----------
 drivers/mtd/spi-nor/core.h  | 10 ++++++
 include/linux/mtd/spi-nor.h |  2 ++
 3 files changed, 60 insertions(+), 18 deletions(-)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index c0d186f417d8..b70c0b2e0958 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -1514,13 +1514,34 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
 	return ret;
 }
 
+static u8 spi_nor_get_sr_bp_mask(struct spi_nor *nor)
+{
+	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
+
+	if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6)
+		return mask | SR_BP3_BIT6;
+
+	if (nor->flags & SNOR_F_HAS_4BIT_BP)
+		return mask | SR_BP3;
+
+	return mask;
+}
+
+static u8 spi_nor_get_sr_tb_mask(struct spi_nor *nor)
+{
+	if (nor->flags & SNOR_F_HAS_SR_TB_BIT6)
+		return SR_TB_BIT6;
+	else
+		return SR_TB_BIT5;
+}
+
 static u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor)
 {
 	unsigned int bp_slots, bp_slots_needed;
-	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
+	u8 mask = spi_nor_get_sr_bp_mask(nor);
 
 	/* Reserved one for "protect none" and one for "protect all". */
-	bp_slots = (mask >> SR_BP_SHIFT) + 1 - 2;
+	bp_slots = (1 << hweight8(mask)) - 2;
 	bp_slots_needed = ilog2(nor->info->n_sectors);
 
 	if (bp_slots_needed > bp_slots)
@@ -1535,12 +1556,14 @@ static void spi_nor_get_locked_range_sr(struct spi_nor *nor, u8 sr, loff_t *ofs,
 {
 	struct mtd_info *mtd = &nor->mtd;
 	u64 min_prot_len;
-	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
-	u8 tb_mask = SR_TB_BIT5;
-	u8 bp = (sr & mask) >> SR_BP_SHIFT;
+	u8 mask = spi_nor_get_sr_bp_mask(nor);
+	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
+	u8 bp, val = sr & mask;
 
-	if (nor->flags & SNOR_F_HAS_SR_TB_BIT6)
-		tb_mask = SR_TB_BIT6;
+	if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3_BIT6)
+		val = (val & ~SR_BP3_BIT6) | SR_BP3;
+
+	bp = val >> SR_BP_SHIFT;
 
 	if (!bp) {
 		/* No protection */
@@ -1598,7 +1621,8 @@ static int spi_nor_is_unlocked_sr(struct spi_nor *nor, loff_t ofs, uint64_t len,
 
 /*
  * Lock a region of the flash. Compatible with ST Micro and similar flash.
- * Supports the block protection bits BP{0,1,2} in the status register
+ * Supports the block protection bits BP{0,1,2}/BP{0,1,2,3} in the status
+ * register
  * (SR). Does not support these features found in newer SR bitfields:
  *   - SEC: sector/block protect - only handle SEC=0 (block protect)
  *   - CMP: complement protect - only support CMP=0 (range is not complemented)
@@ -1633,8 +1657,8 @@ static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 	struct mtd_info *mtd = &nor->mtd;
 	u64 min_prot_len;
 	int ret, status_old, status_new;
-	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
-	u8 tb_mask = SR_TB_BIT5;
+	u8 mask = spi_nor_get_sr_bp_mask(nor);
+	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
 	u8 pow, val;
 	loff_t lock_len;
 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
@@ -1671,9 +1695,6 @@ static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 	else
 		lock_len = ofs + len;
 
-	if (nor->flags & SNOR_F_HAS_SR_TB_BIT6)
-		tb_mask = SR_TB_BIT6;
-
 	if (lock_len == mtd->size) {
 		val = mask;
 	} else {
@@ -1681,6 +1702,9 @@ static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 		pow = ilog2(lock_len) - ilog2(min_prot_len) + 1;
 		val = pow << SR_BP_SHIFT;
 
+		if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)
+			val = (val & ~SR_BP3) | SR_BP3_BIT6;
+
 		if (val & ~mask)
 			return -EINVAL;
 
@@ -1718,8 +1742,8 @@ static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 	struct mtd_info *mtd = &nor->mtd;
 	u64 min_prot_len;
 	int ret, status_old, status_new;
-	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
-	u8 tb_mask = SR_TB_BIT5;
+	u8 mask = spi_nor_get_sr_bp_mask(nor);
+	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
 	u8 pow, val;
 	loff_t lock_len;
 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
@@ -1756,9 +1780,6 @@ static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 	else
 		lock_len = ofs;
 
-	if (nor->flags & SNOR_F_HAS_SR_TB_BIT6)
-		tb_mask = SR_TB_BIT6;
-
 	if (lock_len == 0) {
 		val = 0; /* fully unlocked */
 	} else {
@@ -1766,6 +1787,9 @@ static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
 		pow = ilog2(lock_len) - ilog2(min_prot_len) + 1;
 		val = pow << SR_BP_SHIFT;
 
+		if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)
+			val = (val & ~SR_BP3) | SR_BP3_BIT6;
+
 		/* Some power-of-two sizes are not supported */
 		if (val & ~mask)
 			return -EINVAL;
@@ -3125,6 +3149,12 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
 	if (info->flags & USE_CLSR)
 		nor->flags |= SNOR_F_USE_CLSR;
 
+	if (info->flags & SPI_NOR_4BIT_BP) {
+		nor->flags |= SNOR_F_HAS_4BIT_BP;
+		if (info->flags & SPI_NOR_BP3_SR_BIT6)
+			nor->flags |= SNOR_F_HAS_SR_BP3_BIT6;
+	}
+
 	if (info->flags & SPI_NOR_NO_ERASE)
 		mtd->flags |= MTD_NO_ERASE;
 
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 3ce826b35ad1..6f2f6b27173f 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -24,6 +24,8 @@ enum spi_nor_option_flags {
 	SNOR_F_HAS_16BIT_SR	= BIT(9),
 	SNOR_F_NO_READ_CR	= BIT(10),
 	SNOR_F_HAS_SR_TB_BIT6	= BIT(11),
+	SNOR_F_HAS_4BIT_BP      = BIT(12),
+	SNOR_F_HAS_SR_BP3_BIT6  = BIT(13),
 };
 
 struct spi_nor_read_command {
@@ -301,6 +303,14 @@ struct flash_info {
 					 * status register. Must be used with
 					 * SPI_NOR_HAS_TB.
 					 */
+#define SPI_NOR_4BIT_BP		BIT(17) /*
+					 * Flash SR has 4 bit fields (BP0-3)
+					 * for block protection.
+					 */
+#define SPI_NOR_BP3_SR_BIT6	BIT(18) /*
+					 * BP3 is bit 6 of status register.
+					 * Must be used with SPI_NOR_4BIT_BP.
+					 */
 
 	/* Part specific fixup hooks. */
 	const struct spi_nor_fixups *fixups;
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index e656858b50a5..1e2af0ec1f03 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -111,7 +111,9 @@
 #define SR_BP0			BIT(2)	/* Block protect 0 */
 #define SR_BP1			BIT(3)	/* Block protect 1 */
 #define SR_BP2			BIT(4)	/* Block protect 2 */
+#define SR_BP3			BIT(5)	/* Block protect 3 */
 #define SR_TB_BIT5		BIT(5)	/* Top/Bottom protect */
+#define SR_BP3_BIT6		BIT(6)	/* Block protect 3 */
 #define SR_TB_BIT6		BIT(6)	/* Top/Bottom protect */
 #define SR_SRWD			BIT(7)	/* SR write protect */
 /* Spansion/Cypress specific status bits */
-- 
2.23.0

______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

  parent reply index

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-23  9:24 [PATCH v3 0/5] mtd: spi-nor: Add SR 4bit " Tudor.Ambarus
2020-03-23  9:24 ` [PATCH v3 1/5] mtd: spi-nor: Fix gap in SR block protection locking Tudor.Ambarus
2020-03-23 18:27   ` Michael Walle
2020-03-23 19:20     ` Tudor.Ambarus
2020-03-23 19:54       ` Michael Walle
2020-03-23 20:26         ` Tudor.Ambarus
2020-03-23 21:14           ` Michael Walle
2020-03-23 21:30             ` Tudor.Ambarus
2020-03-23 21:33               ` Tudor.Ambarus
2020-03-23 22:35               ` Michael Walle
2020-03-24  5:37                 ` Tudor.Ambarus
2020-03-24  3:52   ` Jungseung Lee
2020-03-25  9:44   ` Tudor.Ambarus
2020-03-23  9:24 ` [PATCH v3 2/5] mtd: spi-nor: Set all BP bits to one when lock_len == mtd->size Tudor.Ambarus
2020-03-23 14:08   ` Jungseung Lee
2020-03-23 18:28   ` Michael Walle
2020-03-23  9:24 ` [PATCH v3 3/5] mtd: spi-nor: Add new formula for SR block protection handling Tudor.Ambarus
     [not found]   ` <000001d600ff$063a8fd0$12afaf70$@samsung.com>
2020-03-23 13:32     ` Jungseung Lee
2020-03-23  9:24 ` [PATCH v3 4/5] mtd: spi-nor: Add SR 4bit block protection support Tudor.Ambarus
2020-03-23 12:43   ` Jungseung Lee
2020-03-23 12:55     ` Tudor.Ambarus
2020-03-23 13:16       ` Jungseung Lee
2020-03-23 18:33   ` Michael Walle
2020-03-23 18:51     ` Tudor.Ambarus
2020-03-23  9:24 ` Tudor.Ambarus [this message]
2020-03-23  9:46   ` [PATCH v3 4/5] mtd: spi-nor: Add 4bit SR " Tudor.Ambarus
2020-03-23  9:24 ` [PATCH v3 5/5] mtd: spi-nor: Enable locking for n25q512ax3/n25q512a Tudor.Ambarus

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200323092430.1466234-5-tudor.ambarus@microchip.com \
    --to=tudor.ambarus@microchip.com \
    --cc=js07.lee@samsung.com \
    --cc=linux-mtd@lists.infradead.org \
    --cc=michael@walle.cc \
    --cc=vigneshr@ti.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-mtd Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-mtd/0 linux-mtd/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-mtd linux-mtd/ https://lore.kernel.org/linux-mtd \
		linux-mtd@lists.infradead.org
	public-inbox-index linux-mtd

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-mtd


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git