[PATCH v5] mtd: rawnand: macronix: OTP access for MX30LFxG18AC
Arseniy Krasnov
AVKrasnov at sberdevices.ru
Thu Jun 15 02:40:06 PDT 2023
Support for OTP area access on MX30LFxG18AC chip series.
Signed-off-by: Arseniy Krasnov <AVKrasnov at sberdevices.ru>
---
v1 -> v2:
* Add slab.h include due to kernel test robot error.
v2 -> v3:
* Use 'uint64_t' as input argument for 'do_div()' instead
of 'unsigned long' due to kernel test robot error.
v3 -> v4:
* Use 'dev_err()' instead of 'WARN()'.
* Call 'match_string()' before checking 'supports_set_get_features'
in 'macronix_nand_setup_otp().
* Use 'u8' instead of 'uint8_t' as ./checkpatch.pl wants.
v4 -> v5:
* OTP lock logic is disabled. Change locking callback to return
-EOPNOTSUPP. See comment 'macronix_30lfxg18ac_get_otp_info()'
for details.
* OTP factory callbacks are removed. Only user region is supported.
* Temporary DMA buffer in RW function is removed. There is no need
in it.
drivers/mtd/nand/raw/nand_macronix.c | 167 +++++++++++++++++++++++++++
1 file changed, 167 insertions(+)
diff --git a/drivers/mtd/nand/raw/nand_macronix.c b/drivers/mtd/nand/raw/nand_macronix.c
index 385957eb6762..e229de32ff50 100644
--- a/drivers/mtd/nand/raw/nand_macronix.c
+++ b/drivers/mtd/nand/raw/nand_macronix.c
@@ -6,6 +6,7 @@
* Author: Boris Brezillon <boris.brezillon at free-electrons.com>
*/
+#include <linux/slab.h>
#include "linux/delay.h"
#include "internals.h"
@@ -31,6 +32,16 @@
#define MXIC_CMD_POWER_DOWN 0xB9
+#define ONFI_FEATURE_ADDR_30LFXG18AC_OTP 0x90
+#define MACRONIX_30LFXG18AC_OTP_START_PAGE 2
+#define MACRONIX_30LFXG18AC_OTP_PAGES 30
+#define MACRONIX_30LFXG18AC_OTP_PAGE_SIZE 2112
+#define MACRONIX_30LFXG18AC_OTP_SIZE_BYTES \
+ (MACRONIX_30LFXG18AC_OTP_PAGES * \
+ MACRONIX_30LFXG18AC_OTP_PAGE_SIZE)
+
+#define MACRONIX_30LFXG18AC_OTP_EN BIT(0)
+
struct nand_onfi_vendor_macronix {
u8 reserved;
u8 reliability_func;
@@ -315,6 +326,161 @@ static void macronix_nand_deep_power_down_support(struct nand_chip *chip)
chip->ops.resume = mxic_nand_resume;
}
+static int macronix_30lfxg18ac_get_otp_info(struct mtd_info *mtd, size_t len,
+ size_t *retlen,
+ struct otp_info *buf)
+{
+ if (len < sizeof(*buf))
+ return -EINVAL;
+
+ /* Always report that OTP is unlocked. Reason is that this
+ * type of flash chip doesn't provide way to check that OTP
+ * is locked or not: subfeature parameter is implemented as
+ * volatile register. Technically OTP region could be locked
+ * and become readonly, but as there is no way to check it,
+ * don't allow to lock it ('_lock_user_prot_reg' callback
+ * always returns -EOPNOTSUPP) and thus we report that OTP
+ * is unlocked.
+ */
+ buf->locked = 0;
+ buf->start = 0;
+ buf->length = MACRONIX_30LFXG18AC_OTP_SIZE_BYTES;
+
+ *retlen = sizeof(*buf);
+
+ return 0;
+}
+
+static int macronix_30lfxg18ac_otp_enable(struct nand_chip *nand)
+{
+ u8 feature_buf[ONFI_SUBFEATURE_PARAM_LEN] = { 0 };
+
+ feature_buf[0] = MACRONIX_30LFXG18AC_OTP_EN;
+ return nand_set_features(nand, ONFI_FEATURE_ADDR_30LFXG18AC_OTP,
+ feature_buf);
+}
+
+static int macronix_30lfxg18ac_otp_disable(struct nand_chip *nand)
+{
+ u8 feature_buf[ONFI_SUBFEATURE_PARAM_LEN] = { 0 };
+
+ return nand_set_features(nand, ONFI_FEATURE_ADDR_30LFXG18AC_OTP,
+ feature_buf);
+}
+
+static int __macronix_30lfxg18ac_rw_otp(struct mtd_info *mtd,
+ loff_t offs_in_flash,
+ size_t len, size_t *retlen,
+ u_char *buf, bool write)
+{
+ struct nand_chip *nand;
+ size_t bytes_handled;
+ off_t offs_in_page;
+ u64 page;
+ int ret;
+
+ nand = mtd_to_nand(mtd);
+ nand_select_target(nand, 0);
+
+ ret = macronix_30lfxg18ac_otp_enable(nand);
+ if (ret)
+ goto out_otp;
+
+ page = offs_in_flash;
+ /* 'page' will be result of division. */
+ offs_in_page = do_div(page, MACRONIX_30LFXG18AC_OTP_PAGE_SIZE);
+ bytes_handled = 0;
+
+ while (bytes_handled < len &&
+ page < MACRONIX_30LFXG18AC_OTP_PAGES) {
+ size_t bytes_to_handle;
+ u64 phys_page = page + MACRONIX_30LFXG18AC_OTP_START_PAGE;
+
+ bytes_to_handle = min_t(size_t, len - bytes_handled,
+ MACRONIX_30LFXG18AC_OTP_PAGE_SIZE -
+ offs_in_page);
+
+ if (write)
+ ret = nand_prog_page_op(nand, phys_page, offs_in_page,
+ &buf[bytes_handled], bytes_to_handle);
+ else
+ ret = nand_read_page_op(nand, phys_page, offs_in_page,
+ &buf[bytes_handled], bytes_to_handle);
+ if (ret)
+ goto out_otp;
+
+ bytes_handled += bytes_to_handle;
+ offs_in_page = 0;
+ page++;
+ }
+
+ *retlen = bytes_handled;
+
+out_otp:
+ if (ret)
+ dev_err(&mtd->dev, "failed to perform OTP IO: %i\n", ret);
+
+ ret = macronix_30lfxg18ac_otp_disable(nand);
+ if (ret)
+ dev_err(&mtd->dev, "failed to leave OTP mode after %s\n",
+ write ? "write" : "read");
+
+ nand_deselect_target(nand);
+
+ return ret;
+}
+
+static int macronix_30lfxg18ac_write_otp(struct mtd_info *mtd, loff_t to,
+ size_t len, size_t *rlen,
+ const u_char *buf)
+{
+ return __macronix_30lfxg18ac_rw_otp(mtd, to, len, rlen, (u_char *)buf,
+ true);
+}
+
+static int macronix_30lfxg18ac_read_otp(struct mtd_info *mtd, loff_t from,
+ size_t len, size_t *rlen,
+ u_char *buf)
+{
+ return __macronix_30lfxg18ac_rw_otp(mtd, from, len, rlen, buf, false);
+}
+
+static int macronix_30lfxg18ac_lock_otp(struct mtd_info *mtd, loff_t from,
+ size_t len)
+{
+ /* See comment in 'macronix_30lfxg18ac_get_otp_info()'. */
+ return -EOPNOTSUPP;
+}
+
+static void macronix_nand_setup_otp(struct nand_chip *chip)
+{
+ static const char * const supported_otp_models[] = {
+ "MX30LF1G18AC",
+ "MX30LF2G18AC",
+ "MX30LF4G18AC",
+ };
+ struct mtd_info *mtd;
+
+ if (match_string(supported_otp_models,
+ ARRAY_SIZE(supported_otp_models),
+ chip->parameters.model) < 0)
+ return;
+
+ if (!chip->parameters.supports_set_get_features)
+ return;
+
+ bitmap_set(chip->parameters.get_feature_list,
+ ONFI_FEATURE_ADDR_30LFXG18AC_OTP, 1);
+ bitmap_set(chip->parameters.set_feature_list,
+ ONFI_FEATURE_ADDR_30LFXG18AC_OTP, 1);
+
+ mtd = nand_to_mtd(chip);
+ mtd->_get_user_prot_info = macronix_30lfxg18ac_get_otp_info;
+ mtd->_read_user_prot_reg = macronix_30lfxg18ac_read_otp;
+ mtd->_write_user_prot_reg = macronix_30lfxg18ac_write_otp;
+ mtd->_lock_user_prot_reg = macronix_30lfxg18ac_lock_otp;
+}
+
static int macronix_nand_init(struct nand_chip *chip)
{
if (nand_is_slc(chip))
@@ -324,6 +490,7 @@ static int macronix_nand_init(struct nand_chip *chip)
macronix_nand_onfi_init(chip);
macronix_nand_block_protection_support(chip);
macronix_nand_deep_power_down_support(chip);
+ macronix_nand_setup_otp(chip);
return 0;
}
--
2.35.0
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