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-rw-r--r--drivers/mtd/nand/nand_base.c157
-rw-r--r--include/linux/mtd/nand.h14
2 files changed, 167 insertions, 4 deletions
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 1a6310573ab4..f39775b05779 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -948,6 +948,148 @@ static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
}
/**
+ * nand_reset_data_interface - Reset data interface and timings
+ * @chip: The NAND chip
+ *
+ * Reset the Data interface and timings to ONFI mode 0.
+ *
+ * Returns 0 for success or negative error code otherwise.
+ */
+static int nand_reset_data_interface(struct nand_chip *chip)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ const struct nand_data_interface *conf;
+ int ret;
+
+ if (!chip->setup_data_interface)
+ return 0;
+
+ /*
+ * The ONFI specification says:
+ * "
+ * To transition from NV-DDR or NV-DDR2 to the SDR data
+ * interface, the host shall use the Reset (FFh) command
+ * using SDR timing mode 0. A device in any timing mode is
+ * required to recognize Reset (FFh) command issued in SDR
+ * timing mode 0.
+ * "
+ *
+ * Configure the data interface in SDR mode and set the
+ * timings to timing mode 0.
+ */
+
+ conf = nand_get_default_data_interface();
+ ret = chip->setup_data_interface(mtd, conf, false);
+ if (ret)
+ pr_err("Failed to configure data interface to SDR timing mode 0\n");
+
+ return ret;
+}
+
+/**
+ * nand_setup_data_interface - Setup the best data interface and timings
+ * @chip: The NAND chip
+ *
+ * Find and configure the best data interface and NAND timings supported by
+ * the chip and the driver.
+ * First tries to retrieve supported timing modes from ONFI information,
+ * and if the NAND chip does not support ONFI, relies on the
+ * ->onfi_timing_mode_default specified in the nand_ids table.
+ *
+ * Returns 0 for success or negative error code otherwise.
+ */
+static int nand_setup_data_interface(struct nand_chip *chip)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ int ret;
+
+ if (!chip->setup_data_interface || !chip->data_interface)
+ return 0;
+
+ /*
+ * Ensure the timing mode has been changed on the chip side
+ * before changing timings on the controller side.
+ */
+ if (chip->onfi_version) {
+ u8 tmode_param[ONFI_SUBFEATURE_PARAM_LEN] = {
+ chip->onfi_timing_mode_default,
+ };
+
+ ret = chip->onfi_set_features(mtd, chip,
+ ONFI_FEATURE_ADDR_TIMING_MODE,
+ tmode_param);
+ if (ret)
+ goto err;
+ }
+
+ ret = chip->setup_data_interface(mtd, chip->data_interface, false);
+err:
+ return ret;
+}
+
+/**
+ * nand_init_data_interface - find the best data interface and timings
+ * @chip: The NAND chip
+ *
+ * Find the best data interface and NAND timings supported by the chip
+ * and the driver.
+ * First tries to retrieve supported timing modes from ONFI information,
+ * and if the NAND chip does not support ONFI, relies on the
+ * ->onfi_timing_mode_default specified in the nand_ids table. After this
+ * function nand_chip->data_interface is initialized with the best timing mode
+ * available.
+ *
+ * Returns 0 for success or negative error code otherwise.
+ */
+static int nand_init_data_interface(struct nand_chip *chip)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ int modes, mode, ret;
+
+ if (!chip->setup_data_interface)
+ return 0;
+
+ /*
+ * First try to identify the best timings from ONFI parameters and
+ * if the NAND does not support ONFI, fallback to the default ONFI
+ * timing mode.
+ */
+ modes = onfi_get_async_timing_mode(chip);
+ if (modes == ONFI_TIMING_MODE_UNKNOWN) {
+ if (!chip->onfi_timing_mode_default)
+ return 0;
+
+ modes = GENMASK(chip->onfi_timing_mode_default, 0);
+ }
+
+ chip->data_interface = kzalloc(sizeof(*chip->data_interface),
+ GFP_KERNEL);
+ if (!chip->data_interface)
+ return -ENOMEM;
+
+ for (mode = fls(modes) - 1; mode >= 0; mode--) {
+ ret = onfi_init_data_interface(chip, chip->data_interface,
+ NAND_SDR_IFACE, mode);
+ if (ret)
+ continue;
+
+ ret = chip->setup_data_interface(mtd, chip->data_interface,
+ true);
+ if (!ret) {
+ chip->onfi_timing_mode_default = mode;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static void nand_release_data_interface(struct nand_chip *chip)
+{
+ kfree(chip->data_interface);
+}
+
+/**
* nand_reset - Reset and initialize a NAND device
* @chip: The NAND chip
*
@@ -956,9 +1098,18 @@ static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
int nand_reset(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ int ret;
+
+ ret = nand_reset_data_interface(chip);
+ if (ret)
+ return ret;
chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+ ret = nand_setup_data_interface(chip);
+ if (ret)
+ return ret;
+
return 0;
}
@@ -4172,6 +4323,10 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips,
return PTR_ERR(type);
}
+ ret = nand_init_data_interface(chip);
+ if (ret)
+ return ret;
+
chip->select_chip(mtd, -1);
/* Check for a chip array */
@@ -4631,6 +4786,8 @@ void nand_release(struct mtd_info *mtd)
mtd_device_unregister(mtd);
+ nand_release_data_interface(chip);
+
/* Free bad block table memory */
kfree(chip->bbt);
if (!(chip->options & NAND_OWN_BUFFERS))
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 0c9412c2d80b..d3e3f8d03336 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -751,10 +751,9 @@ nand_get_sdr_timings(const struct nand_data_interface *conf)
* also from the datasheet. It is the recommended ECC step
* size, if known; if unknown, set to zero.
* @onfi_timing_mode_default: [INTERN] default ONFI timing mode. This field is
- * either deduced from the datasheet if the NAND
- * chip is not ONFI compliant or set to 0 if it is
- * (an ONFI chip is always configured in mode 0
- * after a NAND reset)
+ * set to the actually used ONFI mode if the chip is
+ * ONFI compliant or deduced from the datasheet if
+ * the NAND chip is not ONFI compliant.
* @numchips: [INTERN] number of physical chips
* @chipsize: [INTERN] the size of one chip for multichip arrays
* @pagemask: [INTERN] page number mask = number of (pages / chip) - 1
@@ -774,6 +773,7 @@ nand_get_sdr_timings(const struct nand_data_interface *conf)
* @read_retries: [INTERN] the number of read retry modes supported
* @onfi_set_features: [REPLACEABLE] set the features for ONFI nand
* @onfi_get_features: [REPLACEABLE] get the features for ONFI nand
+ * @setup_data_interface: [OPTIONAL] setup the data interface and timing
* @bbt: [INTERN] bad block table pointer
* @bbt_td: [REPLACEABLE] bad block table descriptor for flash
* lookup.
@@ -820,6 +820,10 @@ struct nand_chip {
int (*onfi_get_features)(struct mtd_info *mtd, struct nand_chip *chip,
int feature_addr, uint8_t *subfeature_para);
int (*setup_read_retry)(struct mtd_info *mtd, int retry_mode);
+ int (*setup_data_interface)(struct mtd_info *mtd,
+ const struct nand_data_interface *conf,
+ bool check_only);
+
int chip_delay;
unsigned int options;
@@ -849,6 +853,8 @@ struct nand_chip {
struct nand_jedec_params jedec_params;
};
+ struct nand_data_interface *data_interface;
+
int read_retries;
flstate_t state;