mtd: spinand: micron: OTP access for MT29F2G01ABAGD

Support for OTP area access on Micron MT29F2G01ABAGD chip.

Signed-off-by: Martin Kurbanov <mmkurbanov@salutedevices.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/nand/spi/micron.c b/drivers/mtd/nand/spi/micron.c
index ad0bb9755a099dc668e4a0b0a56928f968fba824..691f8a2e0791d0e202812d08520c1a2bfa392c6b 100644 (file)
--- a/drivers/mtd/nand/spi/micron.c
+++ b/drivers/mtd/nand/spi/micron.c
@@ -9,6 +9,8 @@
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/mtd/spinand.h>
+#include <linux/spi/spi-mem.h>
+#include <linux/string.h>
 
 #define SPINAND_MFR_MICRON             0x2c
 
@@ -28,6 +30,10 @@
 
 #define MICRON_SELECT_DIE(x)   ((x) << 6)
 
+#define MICRON_MT29F2G01ABAGD_CFG_OTP_STATE            BIT(7)
+#define MICRON_MT29F2G01ABAGD_CFG_OTP_LOCK             \
+       (CFG_OTP_ENABLE | MICRON_MT29F2G01ABAGD_CFG_OTP_STATE)
+
 static SPINAND_OP_VARIANTS(quadio_read_cache_variants,
                SPINAND_PAGE_READ_FROM_CACHE_QUADIO_OP(0, 2, NULL, 0),
                SPINAND_PAGE_READ_FROM_CACHE_X4_OP(0, 1, NULL, 0),
@@ -168,6 +174,131 @@ static int micron_8_ecc_get_status(struct spinand_device *spinand,
        return -EINVAL;
 }
 
+static int mt29f2g01abagd_otp_is_locked(struct spinand_device *spinand)
+{
+       size_t bufsize = spinand_otp_page_size(spinand);
+       size_t retlen;
+       u8 *buf;
+       int ret;
+
+       buf = kmalloc(bufsize, GFP_KERNEL);
+       if (!buf)
+               return -ENOMEM;
+
+       ret = spinand_upd_cfg(spinand,
+                             MICRON_MT29F2G01ABAGD_CFG_OTP_LOCK,
+                             MICRON_MT29F2G01ABAGD_CFG_OTP_STATE);
+       if (ret)
+               goto free_buf;
+
+       ret = spinand_user_otp_read(spinand, 0, bufsize, &retlen, buf);
+
+       if (spinand_upd_cfg(spinand, MICRON_MT29F2G01ABAGD_CFG_OTP_LOCK,
+                           0)) {
+               dev_warn(&spinand_to_mtd(spinand)->dev,
+                        "Can not disable OTP mode\n");
+               ret = -EIO;
+       }
+
+       if (ret)
+               goto free_buf;
+
+       /* If all zeros, then the OTP area is locked. */
+       if (mem_is_zero(buf, bufsize))
+               ret = 1;
+
+free_buf:
+       kfree(buf);
+       return ret;
+}
+
+static int mt29f2g01abagd_otp_info(struct spinand_device *spinand, size_t len,
+                                  struct otp_info *buf, size_t *retlen,
+                                  bool user)
+{
+       int locked;
+
+       if (len < sizeof(*buf))
+               return -EINVAL;
+
+       locked = mt29f2g01abagd_otp_is_locked(spinand);
+       if (locked < 0)
+               return locked;
+
+       buf->locked = locked;
+       buf->start = 0;
+       buf->length = user ? spinand_user_otp_size(spinand) :
+                            spinand_fact_otp_size(spinand);
+
+       *retlen = sizeof(*buf);
+       return 0;
+}
+
+static int mt29f2g01abagd_fact_otp_info(struct spinand_device *spinand,
+                                       size_t len, struct otp_info *buf,
+                                       size_t *retlen)
+{
+       return mt29f2g01abagd_otp_info(spinand, len, buf, retlen, false);
+}
+
+static int mt29f2g01abagd_user_otp_info(struct spinand_device *spinand,
+                                       size_t len, struct otp_info *buf,
+                                       size_t *retlen)
+{
+       return mt29f2g01abagd_otp_info(spinand, len, buf, retlen, true);
+}
+
+static int mt29f2g01abagd_otp_lock(struct spinand_device *spinand, loff_t from,
+                                  size_t len)
+{
+       struct spi_mem_op write_op = SPINAND_WR_EN_DIS_OP(true);
+       struct spi_mem_op exec_op = SPINAND_PROG_EXEC_OP(0);
+       u8 status;
+       int ret;
+
+       ret = spinand_upd_cfg(spinand,
+                             MICRON_MT29F2G01ABAGD_CFG_OTP_LOCK,
+                             MICRON_MT29F2G01ABAGD_CFG_OTP_LOCK);
+       if (!ret)
+               return ret;
+
+       ret = spi_mem_exec_op(spinand->spimem, &write_op);
+       if (!ret)
+               goto out;
+
+       ret = spi_mem_exec_op(spinand->spimem, &exec_op);
+       if (!ret)
+               goto out;
+
+       ret = spinand_wait(spinand,
+                          SPINAND_WRITE_INITIAL_DELAY_US,
+                          SPINAND_WRITE_POLL_DELAY_US,
+                          &status);
+       if (!ret && (status & STATUS_PROG_FAILED))
+               ret = -EIO;
+
+out:
+       if (spinand_upd_cfg(spinand, MICRON_MT29F2G01ABAGD_CFG_OTP_LOCK, 0)) {
+               dev_warn(&spinand_to_mtd(spinand)->dev,
+                        "Can not disable OTP mode\n");
+               ret = -EIO;
+       }
+
+       return ret;
+}
+
+static const struct spinand_user_otp_ops mt29f2g01abagd_user_otp_ops = {
+       .info = mt29f2g01abagd_user_otp_info,
+       .lock = mt29f2g01abagd_otp_lock,
+       .read = spinand_user_otp_read,
+       .write = spinand_user_otp_write,
+};
+
+static const struct spinand_fact_otp_ops mt29f2g01abagd_fact_otp_ops = {
+       .info = mt29f2g01abagd_fact_otp_info,
+       .read = spinand_fact_otp_read,
+};
+
 static const struct spinand_info micron_spinand_table[] = {
        /* M79A 2Gb 3.3V */
        SPINAND_INFO("MT29F2G01ABAGD",
@@ -179,7 +310,9 @@ static const struct spinand_info micron_spinand_table[] = {
                                              &x4_update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&micron_8_ooblayout,
-                                    micron_8_ecc_get_status)),
+                                    micron_8_ecc_get_status),
+                    SPINAND_USER_OTP_INFO(12, 2, &mt29f2g01abagd_user_otp_ops),
+                    SPINAND_FACT_OTP_INFO(2, 0, &mt29f2g01abagd_fact_otp_ops)),
        /* M79A 2Gb 1.8V */
        SPINAND_INFO("MT29F2G01ABBGD",
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x25),