[PATCH] [MTD] MTD driver for LPDDR2-NVM PCM memories
Vincenzo Aliberti
vincenzo.aliberti at gmail.com
Tue Oct 16 17:24:44 EDT 2012
On 10/11/2012 01:20 PM, Artem Bityutskiy wrote:> On Thu, 2012-10-04 at 23:17 +0200, Vincenzo Aliberti wrote:
>> +menu "LPDDR2_NVM memory drivers"
>> + depends on MTD!=n
>
> Just 'depends on MTD'
>
Done
>> +# linux/drivers/mtd/lpddr2_nvm/Makefile
>
> Why did you decide to create a separate directory for this one?
> I think you should just put it to 'drivers/mtd/lpddr' instead.
>
Now both drivers are in the same folder as per your suggestion
On 10/11/2012 01:22 PM, Artem Bityutskiy wrote:
> On Thu, 2012-10-04 at 23:17 +0200, Vincenzo Aliberti wrote:
>> Dear All,
>> continuing Micron support activity on PCM memories you can find here-below a
>> patch containing MTD driver for LPDDR2-NVM memories as demoed during Q2 Linaro
>> Connect in Hong Kong.
>>
>> Let me thank TI Panda open source team for support on platform enablement
>> activity and Arnd for his first feedback on driver implementation
>
> include/mtd/mtd-abi.h file does not longer exist, please re-base your
> driver. Could you please also feed it to the checkpatch.pl tool and fix
> style issues?
>
The only Warning is
WARNING: line over 80 characters
#605: FILE: include/uapi/mtd/mtd-abi.h:112:
+#define MTD_CAP_PCM (MTD_WRITEABLE | MTD_BIT_WRITEABLE | MTD_NO_ERASE)
But in the file include/uapi/mtd/mtd-abi.h there is already the raw:
#define MTD_CAP_RAM (MTD_WRITEABLE | MTD_BIT_WRITEABLE | MTD_NO_ERASE)
>> + pr_alert(
>> + "lpddr2_nvm_probe: Failed to allocate memory for map\n");
>
> Just join this into 1 line. It is OK to have lines longer than 80
> sybmols if you print a string.
>
> Do this for all other similar places please.
>
Done
Considering the number of changes you can find here-below the whole patch: I have
successfully compiled it with 3.7-rc1
Regards.
Vincenzo Aliberti
Signed-off-by: Vincenzo Aliberti <vincenzo.aliberti at gmail.com>
---
drivers/mtd/lpddr/Kconfig | 12 +-
drivers/mtd/lpddr/Makefile | 1 +
drivers/mtd/lpddr/lpddr2_nvm.c | 542 ++++++++++++++++++++++++++++++++++++++++
include/uapi/mtd/mtd-abi.h | 1 +
4 files changed, 554 insertions(+), 2 deletions(-)
create mode 100644 drivers/mtd/lpddr/lpddr2_nvm.c
diff --git a/drivers/mtd/lpddr/Kconfig b/drivers/mtd/lpddr/Kconfig
index 265f969..468f06d 100644
--- a/drivers/mtd/lpddr/Kconfig
+++ b/drivers/mtd/lpddr/Kconfig
@@ -1,5 +1,5 @@
-menu "LPDDR flash memory drivers"
- depends on MTD!=n
+menu "LPDDR & LPDDR2 PCM memory drivers"
+ depends on MTD
config MTD_LPDDR
tristate "Support for LPDDR flash chips"
@@ -17,4 +17,12 @@ config MTD_QINFO_PROBE
Window QINFO interface, permits software to be used for entire
families of devices. This serves similar purpose of CFI on legacy
Flash products
+
+config MTD_LPDDR2_NVM
+ depends on MTD
+ tristate "Support for LPDDR2-NVM flash chips"
+ help
+ This option enables support of PCM memories with a LPDDR2-NVM
+ (Low power double data rate 2) interface.
+
endmenu
diff --git a/drivers/mtd/lpddr/Makefile b/drivers/mtd/lpddr/Makefile
index da48e46..881d440 100644
--- a/drivers/mtd/lpddr/Makefile
+++ b/drivers/mtd/lpddr/Makefile
@@ -4,3 +4,4 @@
obj-$(CONFIG_MTD_QINFO_PROBE) += qinfo_probe.o
obj-$(CONFIG_MTD_LPDDR) += lpddr_cmds.o
+obj-$(CONFIG_MTD_LPDDR2_NVM) += lpddr2_nvm.o
diff --git a/drivers/mtd/lpddr/lpddr2_nvm.c b/drivers/mtd/lpddr/lpddr2_nvm.c
new file mode 100644
index 0000000..8e74287
--- /dev/null
+++ b/drivers/mtd/lpddr/lpddr2_nvm.c
@@ -0,0 +1,542 @@
+/*
+ * LPDDR2-NVM MTD driver. This module provides read, write, erase, lock/unlock
+ * support for LPDDR2-NVM PCM memories
+ *
+ * Copyright © 2012 Micron Technology, Inc.
+ *
+ * Vincenzo Aliberti <vincenzo.aliberti at gmail.com>
+ * Domenico Manna <domenico.manna at gmail.com>
+ * Many thanks to Andrea Vigilante for initial enabling
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/ioport.h>
+#include <linux/sched.h>
+
+/* Parameters */
+#define ERASE_BLOCKSIZE (0x00020000/2) /* in Word */
+#define WRITE_BUFFSIZE (0x00000400/2) /* in Word */
+#define OW_BASE_ADDRESS 0x00000000 /* OW offset */
+
+/* PFOW symbols address offset */
+#define PFOW_QUERY_STRING_P (0x0000/2) /* in Word */
+#define PFOW_QUERY_STRING_F (0x0002/2) /* in Word */
+#define PFOW_QUERY_STRING_O (0x0004/2) /* in Word */
+#define PFOW_QUERY_STRING_W (0x0006/2) /* in Word */
+
+/* OW registers address */
+#define CMD_CODE_OFS (0x0080/2) /* in Word */
+#define CMD_DATA_OFS (0x0084/2) /* in Word */
+#define CMD_ADD_L_OFS (0x0088/2) /* in Word */
+#define CMD_ADD_H_OFS (0x008A/2) /* in Word */
+#define MPR_L_OFS (0x0090/2) /* in Word */
+#define MPR_H_OFS (0x0092/2) /* in Word */
+#define CMD_EXEC_OFS (0x00C0/2) /* in Word */
+#define STATUS_REG_OFS (0x00CC/2) /* in Word */
+#define PRG_BUFFER_OFS (0x0010/2) /* in Word */
+
+/* Datamask */
+#define MR_CFGMASK 0x8000
+#define SR_OK_DATAMASK 0x0080
+
+/* LPDDR2-NVM Commands */
+#define LPDDR2_NVM_LOCK 0x0061
+#define LPDDR2_NVM_UNLOCK 0x0062
+#define LPDDR2_NVM_SW_PROGRAM 0x0041
+#define LPDDR2_NVM_SW_OVERWRITE 0x0042
+#define LPDDR2_NVM_BUF_PROGRAM 0x00E9
+#define LPDDR2_NVM_BUF_OVERWRITE 0x00EA
+#define LPDDR2_NVM_ERASE 0x0020
+
+/*
+ * Internal Type Definitions
+ * pcm_int_data contains memory controller details:
+ * @reg_data : LPDDR2_MODE_REG_DATA register address after remapping
+ * @reg_cfg : LPDDR2_MODE_REG_CFG register address after remapping
+ * &bus_width: memory bus-width (eg: x16 2 Bytes, x32 4 Bytes)
+ */
+struct pcm_int_data {
+ void __iomem *reg_data;
+ void __iomem *reg_cfg;
+ int bus_width;
+};
+
+static DEFINE_MUTEX(lpdd2_nvm_mutex);
+
+static inline map_word build_map_word(u_long myword)
+{
+ map_word val = { {0} };
+ val.x[0] = myword;
+ return val;
+}
+
+static inline u_int build_mr_cfgmaks(u_int bus_width)
+{
+ u_int val = MR_CFGMASK;
+
+ if (bus_width == 0x0004) /* x32 device */
+ val = val<<16;
+
+ return val;
+}
+
+static inline u_int build_sr_ok_datamask(u_int bus_width)
+{
+ u_int val = SR_OK_DATAMASK;
+
+ if (bus_width == 0x0004) /* x32 device */
+ val = (val<<16)+val;
+
+ return val;
+}
+
+/*
+ * Enable lpddr2-nvm Overlay Window
+ */
+static inline void ow_enable(struct map_info *map)
+{
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+
+ writel_relaxed(build_mr_cfgmaks(pcm_data->bus_width) | 0x18,
+ pcm_data->reg_cfg);
+ writel_relaxed(0x01, pcm_data->reg_data);
+}
+
+/*
+ * Disable lpddr2-nvm Overlay Window
+ */
+static inline void ow_disable(struct map_info *map)
+{
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+
+ writel_relaxed(build_mr_cfgmaks(pcm_data->bus_width) | 0x18,
+ pcm_data->reg_cfg);
+ writel_relaxed(0x02, pcm_data->reg_data);
+}
+
+/*
+ * Execute lpddr2-nvm operations
+ */
+static int lpddr2_nvm_do_op(struct map_info *map, u_long cmd_code,
+ u_long cmd_data, u_long cmd_add, u_long cmd_mpr, u_char *buf)
+{
+ map_word add_l = { {0} }, add_h = { {0} }, mpr_l = { {0} },
+ mpr_h = { {0} }, data_l = { {0} }, cmd = { {0} },
+ exec_cmd = { {0} }, sr;
+ map_word data_h = { {0} }; /* only for 2x x16 devices stacked */
+ u_long i, status_reg, prg_buff_ofs;
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+ u_int sr_ok_datamask = build_sr_ok_datamask(pcm_data->bus_width);
+
+ /* Builds low and high words for OW Control Registers */
+ add_l.x[0] = cmd_add&0x0000FFFF;
+ add_h.x[0] = (cmd_add>>16)&0x0000FFFF;
+ mpr_l.x[0] = cmd_mpr&0x0000FFFF;
+ mpr_h.x[0] = (cmd_mpr>>16)&0x0000FFFF;
+ cmd.x[0] = cmd_code&0x0000FFFF;
+ exec_cmd.x[0] = 0x0001;
+ data_l.x[0] = cmd_data&0x0000FFFF;
+ data_h.x[0] = (cmd_data>>16)&0x0000FFFF; /* only for 2x x16 */
+
+ /* Set Overlay Window Control Registers */
+ map_write(map, cmd, map->pfow_base+CMD_CODE_OFS*pcm_data->bus_width);
+ map_write(map, data_l, map->pfow_base+CMD_DATA_OFS*pcm_data->bus_width);
+ map_write(map, add_l, map->pfow_base+CMD_ADD_L_OFS*pcm_data->bus_width);
+ map_write(map, add_h, map->pfow_base+CMD_ADD_H_OFS*pcm_data->bus_width);
+ map_write(map, mpr_l, map->pfow_base+MPR_L_OFS*pcm_data->bus_width);
+ map_write(map, mpr_h, map->pfow_base+MPR_H_OFS*pcm_data->bus_width);
+ if (pcm_data->bus_width == 0x0004) { /* 2x16 devices stacked */
+ map_write(map, cmd, map->pfow_base +
+ CMD_CODE_OFS*pcm_data->bus_width + 2);
+ map_write(map, data_h, map->pfow_base +
+ CMD_DATA_OFS*pcm_data->bus_width + 2);
+ map_write(map, add_l, map->pfow_base +
+ CMD_ADD_L_OFS*pcm_data->bus_width + 2);
+ map_write(map, add_h, map->pfow_base +
+ CMD_ADD_H_OFS*pcm_data->bus_width + 2);
+ map_write(map, mpr_l, map->pfow_base +
+ MPR_L_OFS*pcm_data->bus_width + 2);
+ map_write(map, mpr_h, map->pfow_base +
+ MPR_H_OFS*pcm_data->bus_width + 2);
+ }
+
+ /* Fill Program Buffer */
+ if ((cmd_code == LPDDR2_NVM_BUF_PROGRAM) ||
+ (cmd_code == LPDDR2_NVM_BUF_OVERWRITE)) {
+ prg_buff_ofs = (map_read(map, map->pfow_base +
+ PRG_BUFFER_OFS*pcm_data->bus_width)).x[0];
+ for (i = 0; i < cmd_mpr; i++) {
+ map_write(map, build_map_word(buf[i]), map->pfow_base +
+ prg_buff_ofs + i);
+ }
+ }
+
+ /* Command Execute */
+ map_write(map, exec_cmd, map->pfow_base+CMD_EXEC_OFS*
+ pcm_data->bus_width);
+ if (pcm_data->bus_width == 0x0004) /* 2x16 devices stacked */
+ map_write(map, exec_cmd, map->pfow_base +
+ CMD_EXEC_OFS*pcm_data->bus_width + 2);
+
+ /* Status Register Check */
+ do {
+ sr = map_read(map, map->pfow_base +
+ STATUS_REG_OFS*pcm_data->bus_width);
+ status_reg = sr.x[0];
+ if (pcm_data->bus_width == 0x0004) {/* 2x16 devices stacked */
+ sr = map_read(map, map->pfow_base +
+ STATUS_REG_OFS*pcm_data->bus_width + 2);
+ status_reg += sr.x[0]<<16;
+ }
+ } while ((status_reg&sr_ok_datamask) != sr_ok_datamask);
+
+ return (((status_reg&sr_ok_datamask) == sr_ok_datamask) ? 0 : -EIO);
+}
+
+/*
+ * Execute lpddr2-nvm operations @ block level
+ */
+static int lpddr2_nvm_do_block_op(struct mtd_info *mtd, loff_t start_add,
+ uint64_t len, u_char block_op)
+{
+ struct map_info *map = mtd->priv;
+ u_long add, end_add;
+ int ret = 0;
+
+ mutex_lock(&lpdd2_nvm_mutex);
+
+ ow_enable(map);
+
+ add = start_add;
+ end_add = add + len;
+
+ if ((add > mtd->size) || (end_add > mtd->size)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ do {
+ ret = lpddr2_nvm_do_op(map, block_op, 0x00, add, add, NULL);
+ if (ret)
+ goto out;
+ add += mtd->erasesize;
+ } while (add < end_add);
+
+out:
+ ow_disable(map);
+ mutex_unlock(&lpdd2_nvm_mutex);
+ return ret;
+}
+
+/*
+ * verify presence of PFOW string
+ */
+static int lpddr2_nvm_pfow_present(struct map_info *map)
+{
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+ map_word pfow_val[4];
+ unsigned int found = 1;
+
+ mutex_lock(&lpdd2_nvm_mutex);
+
+ ow_enable(map);
+
+ /* Load string from array */
+ pfow_val[0] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_P *
+ pcm_data->bus_width);
+ pfow_val[1] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_F *
+ pcm_data->bus_width);
+ pfow_val[2] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_O *
+ pcm_data->bus_width);
+ pfow_val[3] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_W *
+ pcm_data->bus_width);
+
+ /* Verify the string loaded vs expected */
+ if (!map_word_equal(map, build_map_word('P'), pfow_val[0]))
+ found = 0;
+ if (!map_word_equal(map, build_map_word('F'), pfow_val[1]))
+ found = 0;
+ if (!map_word_equal(map, build_map_word('O'), pfow_val[2]))
+ found = 0;
+ if (!map_word_equal(map, build_map_word('W'), pfow_val[3]))
+ found = 0;
+
+ ow_disable(map);
+
+ mutex_unlock(&lpdd2_nvm_mutex);
+
+ return found;
+}
+
+/*
+ * lpddr2_nvm driver read method
+ */
+static int lpddr2_nvm_read(struct mtd_info *mtd, loff_t start_add,
+ size_t len, size_t *retlen, u_char *buf)
+{
+ struct map_info *map = mtd->priv;
+ int ret = 0;
+
+ mutex_lock(&lpdd2_nvm_mutex);
+
+ *retlen = len;
+
+ if ((start_add + len) > mtd->size) {
+ pr_alert("lpddr2_nvm: read out of memory range\n");
+ *retlen = 0;
+ ret = -EINVAL;
+ goto out;
+ }
+
+ map_copy_from(map, buf, start_add, *retlen);
+
+out:
+ mutex_unlock(&lpdd2_nvm_mutex);
+ return ret;
+}
+
+/*
+ * lpddr2_nvm driver write method
+ */
+static int lpddr2_nvm_write(struct mtd_info *mtd, loff_t start_add,
+ size_t len, size_t *retlen, const u_char *buf)
+{
+ struct map_info *map = mtd->priv;
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+ u_long add, current_len, tot_len, target_len, my_data;
+ u_char *write_buf = (u_char *)buf;
+ int ret = 0;
+
+ mutex_lock(&lpdd2_nvm_mutex);
+
+ ow_enable(map);
+
+ /* Set start value for the variables */
+ add = start_add;
+ target_len = len;
+ tot_len = 0;
+
+ if ((start_add + len) > mtd->size) {
+ pr_alert("lpddr2_nvm: write out of memory range\n");
+ *retlen = 0;
+ ret = -EINVAL;
+ goto out;
+ }
+
+ while (tot_len < target_len) {
+ if (!(IS_ALIGNED(add, mtd->writesize))) { /* do sw program */
+ my_data = write_buf[tot_len];
+ my_data += (write_buf[tot_len+1])<<8;
+ if (pcm_data->bus_width == 0x0004) {/* 2x16 devices */
+ my_data += (write_buf[tot_len+2])<<16;
+ my_data += (write_buf[tot_len+3])<<24;
+ }
+ ret = lpddr2_nvm_do_op(map, LPDDR2_NVM_SW_OVERWRITE,
+ my_data, add, 0x00, NULL);
+ if (ret)
+ goto out;
+
+ add += pcm_data->bus_width;
+ tot_len += pcm_data->bus_width;
+ } else { /* do buffer program */
+ current_len = min(target_len - tot_len,
+ (u_long) mtd->writesize);
+ ret = lpddr2_nvm_do_op(map, LPDDR2_NVM_BUF_OVERWRITE,
+ 0x00, add, current_len, write_buf + tot_len);
+ if (ret)
+ goto out;
+
+ add += current_len;
+ tot_len += current_len;
+ }
+ }
+
+out:
+ *retlen = tot_len;
+ ow_disable(map);
+ mutex_unlock(&lpdd2_nvm_mutex);
+ return ret;
+}
+
+/*
+ * lpddr2_nvm driver erase method
+ */
+static int lpddr2_nvm_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+ int ret = lpddr2_nvm_do_block_op(mtd, instr->addr, instr->len,
+ LPDDR2_NVM_ERASE);
+ if (!ret) {
+ instr->state = MTD_ERASE_DONE;
+ mtd_erase_callback(instr);
+ }
+
+ return ret;
+}
+
+/*
+ * lpddr2_nvm driver unlock method
+ */
+static int lpddr2_nvm_unlock(struct mtd_info *mtd, loff_t start_add,
+ uint64_t len)
+{
+ return lpddr2_nvm_do_block_op(mtd, start_add, len, LPDDR2_NVM_UNLOCK);
+}
+
+/*
+ * lpddr2_nvm driver lock method
+ */
+static int lpddr2_nvm_lock(struct mtd_info *mtd, loff_t start_add,
+ uint64_t len)
+{
+ return lpddr2_nvm_do_block_op(mtd, start_add, len, LPDDR2_NVM_LOCK);
+}
+
+/*
+ * lpddr2_nvm driver probe method
+ */
+static int lpddr2_nvm_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct map_info *lpddr2_nvm_map;
+ struct mtd_info *lpddr2_nvm_mtd;
+ struct resource *address_range = platform_get_resource(pdev,
+ IORESOURCE_MEM, 0);
+ struct resource *control_regs = platform_get_resource(pdev,
+ IORESOURCE_MEM, 1);
+ struct resource *buswidth = platform_get_resource(pdev,
+ IORESOURCE_BUS, 0);
+ struct pcm_int_data *pcm_data;
+
+ /* Allocate memory control_regs data structures */
+ pcm_data = kzalloc(sizeof(*pcm_data), GFP_KERNEL);
+ if (!control_regs) {
+ pr_alert("lpddr2_nvm_probe: Failed to allocate memory for int_data\n");
+ ret = 1;
+ goto out;
+ }
+ pcm_data->reg_data = (void *) control_regs->start;
+ pcm_data->reg_cfg = (void *) control_regs->end;
+ pcm_data->bus_width = (int) buswidth->start;
+
+ /* Allocate memory for map_info & mtd_info data structures */
+ lpddr2_nvm_map = kzalloc(sizeof(*lpddr2_nvm_map), GFP_KERNEL);
+ if (!lpddr2_nvm_map) {
+ pr_alert("lpddr2_nvm_probe: Failed to allocate memory for map\n");
+ ret = 1;
+ goto out;
+ }
+
+ lpddr2_nvm_mtd = kzalloc(sizeof(*lpddr2_nvm_mtd), GFP_KERNEL);
+ if (!lpddr2_nvm_mtd) {
+ pr_alert("lpddr2_nvm_probe: Failed to allocate memory for mtd\n");
+ ret = 1;
+ goto out;
+ }
+
+ /* Reserve lpddr2_nvm address range */
+ if (request_mem_region(address_range->start, (address_range->end -
+ address_range->start + 1), "lpddr2_nvm") == NULL) {
+ pr_alert("lpddr2_nvm_probe: Unable to reserve memory address %#010x\n",
+ address_range->start);
+ ret = -EBUSY;
+ goto out;
+ }
+
+ /* Populate map_info data structure */
+ *lpddr2_nvm_map = (struct map_info) {
+ .virt = ioremap_nocache(address_range->start,
+ (address_range->end-address_range->start+1)),
+ .name = pdev->dev.init_name,
+ .phys = address_range->start,
+ .size = address_range->end - address_range->start + 1,
+ .bankwidth = pcm_data->bus_width/2,
+ .pfow_base = OW_BASE_ADDRESS,
+ .fldrv_priv = pcm_data,
+ };
+
+ simple_map_init(lpddr2_nvm_map); /* fill with default methods */
+
+ /* Populate mtd_info data structure */
+ *lpddr2_nvm_mtd = (struct mtd_info) {
+ .name = pdev->dev.init_name,
+ .type = MTD_RAM,
+ .priv = lpddr2_nvm_map,
+ .size = address_range->end - address_range->start + 1,
+ .erasesize = ERASE_BLOCKSIZE * pcm_data->bus_width,
+ .writesize = 1,
+ .writebufsize = WRITE_BUFFSIZE * pcm_data->bus_width,
+ .flags = (MTD_CAP_PCM | MTD_POWERUP_LOCK),
+ ._read = lpddr2_nvm_read,
+ ._read_oob = NULL,
+ ._write = lpddr2_nvm_write,
+ ._write_oob = NULL,
+ ._erase = lpddr2_nvm_erase,
+ ._unlock = lpddr2_nvm_unlock,
+ ._lock = lpddr2_nvm_lock,
+ ._sync = NULL,
+ ._suspend = NULL,
+ ._resume = NULL,
+ ._block_isbad = NULL,
+ ._block_markbad = NULL,
+ };
+
+ /* Verify the presence of the device looking for PFOW string */
+ if (lpddr2_nvm_pfow_present(lpddr2_nvm_map)) {
+ pr_alert("lpddr2_nvm_probe: device recognized\n");
+ /* Register the mtd_partition structure */
+ if (mtd_add_partition(lpddr2_nvm_mtd, "my_pcm", 0x10000000,
+ 0x00)){
+ pr_alert("lpddr2_nvm_probe: Failed to add mtd partition\n");
+ ret = 1;
+ goto out;
+ }
+ ret = 0;
+ } else {
+ pr_alert("%s: PFOW string not found at address %#010lx\n",
+ lpddr2_nvm_map->name, lpddr2_nvm_map->pfow_base);
+ ret = 1;
+ }
+
+out:
+ return ret;
+}
+
+/* Initialize platform_driver data structure for lpddr2_nvm */
+static struct platform_driver lpddr2_nvm_drv = {
+ .driver = {
+ .name = "lpddr2_nvm",
+ },
+ .probe = lpddr2_nvm_probe,
+ .remove = NULL,
+ .suspend = NULL,
+ .resume = NULL,
+};
+
+module_platform_driver(lpddr2_nvm_drv);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Vincenzo Aliberti <vincenzo.aliberti at gmail.com>");
+MODULE_DESCRIPTION("MTD driver for LPDDR2-NVM PCM memories");
+
diff --git a/include/uapi/mtd/mtd-abi.h b/include/uapi/mtd/mtd-abi.h
index 36eace0..33f3036 100644
--- a/include/uapi/mtd/mtd-abi.h
+++ b/include/uapi/mtd/mtd-abi.h
@@ -109,6 +109,7 @@ struct mtd_write_req {
#define MTD_CAP_RAM (MTD_WRITEABLE | MTD_BIT_WRITEABLE | MTD_NO_ERASE)
#define MTD_CAP_NORFLASH (MTD_WRITEABLE | MTD_BIT_WRITEABLE)
#define MTD_CAP_NANDFLASH (MTD_WRITEABLE)
+#define MTD_CAP_PCM (MTD_WRITEABLE | MTD_BIT_WRITEABLE | MTD_NO_ERASE)
/* Obsolete ECC byte placement modes (used with obsolete MEMGETOOBSEL) */
#define MTD_NANDECC_OFF 0 // Switch off ECC (Not recommended)
--
1.7.9.5
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