mtd: lpddr: add driver for LPDDR2-NVM PCM memories
Linux-MTD Mailing List
linux-mtd at lists.infradead.org
Tue Jun 10 23:59:08 PDT 2014
Gitweb: http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=96ba9dd65788a0bd2a7d1e57ec78b7642f0ccc25
Commit: 96ba9dd65788a0bd2a7d1e57ec78b7642f0ccc25
Parent: 5a4c4c5eb1939fff1a95d0812d01731cdda3694a
Author: Vincenzo Aliberti <vincenzo.aliberti at gmail.com>
AuthorDate: Thu May 15 23:19:32 2014 +0200
Committer: Brian Norris <computersforpeace at gmail.com>
CommitDate: Tue May 20 17:45:17 2014 -0700
mtd: lpddr: add driver for LPDDR2-NVM PCM memories
Signed-off-by: Vincenzo Aliberti <vincenzo.aliberti at gmail.com>
Signed-off-by: Brian Norris <computersforpeace at gmail.com>
---
drivers/mtd/lpddr/Kconfig | 12 +-
drivers/mtd/lpddr/Makefile | 1 +
drivers/mtd/lpddr/lpddr2_nvm.c | 507 +++++++++++++++++++++++++++++++++++++++++
include/uapi/mtd/mtd-abi.h | 1 +
4 files changed, 519 insertions(+), 2 deletions(-)
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..063cec4
--- /dev/null
+++ b/drivers/mtd/lpddr/lpddr2_nvm.c
@@ -0,0 +1,507 @@
+/*
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
+
+#include <linux/init.h>
+#include <linux/io.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/err.h>
+
+/* Parameters */
+#define ERASE_BLOCKSIZE (0x00020000/2) /* in Word */
+#define WRITE_BUFFSIZE (0x00000400/2) /* in Word */
+#define OW_BASE_ADDRESS 0x00000000 /* OW offset */
+#define BUS_WIDTH 0x00000020 /* x32 devices */
+
+/* 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
+
+/* LPDDR2-NVM Registers offset */
+#define LPDDR2_MODE_REG_DATA 0x0040
+#define LPDDR2_MODE_REG_CFG 0x0050
+
+/*
+ * 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 *ctl_regs;
+ int bus_width;
+};
+
+static DEFINE_MUTEX(lpdd2_nvm_mutex);
+
+/*
+ * Build a map_word starting from an u_long
+ */
+static inline map_word build_map_word(u_long myword)
+{
+ map_word val = { {0} };
+ val.x[0] = myword;
+ return val;
+}
+
+/*
+ * Build Mode Register Configuration DataMask based on device bus-width
+ */
+static inline u_int build_mr_cfgmask(u_int bus_width)
+{
+ u_int val = MR_CFGMASK;
+
+ if (bus_width == 0x0004) /* x32 device */
+ val = val << 16;
+
+ return val;
+}
+
+/*
+ * Build Status Register OK DataMask based on device bus-width
+ */
+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;
+}
+
+/*
+ * Evaluates Overlay Window Control Registers address
+ */
+static inline u_long ow_reg_add(struct map_info *map, u_long offset)
+{
+ u_long val = 0;
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+
+ val = map->pfow_base + offset*pcm_data->bus_width;
+
+ return val;
+}
+
+/*
+ * Enable lpddr2-nvm Overlay Window
+ * Overlay Window is a memory mapped area containing all LPDDR2-NVM registers
+ * used by device commands as well as uservisible resources like Device Status
+ * Register, Device ID, etc
+ */
+static inline void ow_enable(struct map_info *map)
+{
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+
+ writel_relaxed(build_mr_cfgmask(pcm_data->bus_width) | 0x18,
+ pcm_data->ctl_regs + LPDDR2_MODE_REG_CFG);
+ writel_relaxed(0x01, pcm_data->ctl_regs + LPDDR2_MODE_REG_DATA);
+}
+
+/*
+ * Disable lpddr2-nvm Overlay Window
+ * Overlay Window is a memory mapped area containing all LPDDR2-NVM registers
+ * used by device commands as well as uservisible resources like Device Status
+ * Register, Device ID, etc
+ */
+static inline void ow_disable(struct map_info *map)
+{
+ struct pcm_int_data *pcm_data = map->fldrv_priv;
+
+ writel_relaxed(build_mr_cfgmask(pcm_data->bus_width) | 0x18,
+ pcm_data->ctl_regs + LPDDR2_MODE_REG_CFG);
+ writel_relaxed(0x02, pcm_data->ctl_regs + LPDDR2_MODE_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, ow_reg_add(map, CMD_CODE_OFS));
+ map_write(map, data_l, ow_reg_add(map, CMD_DATA_OFS));
+ map_write(map, add_l, ow_reg_add(map, CMD_ADD_L_OFS));
+ map_write(map, add_h, ow_reg_add(map, CMD_ADD_H_OFS));
+ map_write(map, mpr_l, ow_reg_add(map, MPR_L_OFS));
+ map_write(map, mpr_h, ow_reg_add(map, MPR_H_OFS));
+ if (pcm_data->bus_width == 0x0004) { /* 2x16 devices stacked */
+ map_write(map, cmd, ow_reg_add(map, CMD_CODE_OFS) + 2);
+ map_write(map, data_h, ow_reg_add(map, CMD_DATA_OFS) + 2);
+ map_write(map, add_l, ow_reg_add(map, CMD_ADD_L_OFS) + 2);
+ map_write(map, add_h, ow_reg_add(map, CMD_ADD_H_OFS) + 2);
+ map_write(map, mpr_l, ow_reg_add(map, MPR_L_OFS) + 2);
+ map_write(map, mpr_h, ow_reg_add(map, MPR_H_OFS) + 2);
+ }
+
+ /* Fill Program Buffer */
+ if ((cmd_code == LPDDR2_NVM_BUF_PROGRAM) ||
+ (cmd_code == LPDDR2_NVM_BUF_OVERWRITE)) {
+ prg_buff_ofs = (map_read(map,
+ ow_reg_add(map, PRG_BUFFER_OFS))).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, ow_reg_add(map, CMD_EXEC_OFS));
+ if (pcm_data->bus_width == 0x0004) /* 2x16 devices stacked */
+ map_write(map, exec_cmd, ow_reg_add(map, CMD_EXEC_OFS) + 2);
+
+ /* Status Register Check */
+ do {
+ sr = map_read(map, ow_reg_add(map, STATUS_REG_OFS));
+ status_reg = sr.x[0];
+ if (pcm_data->bus_width == 0x0004) {/* 2x16 devices stacked */
+ sr = map_read(map, ow_reg_add(map,
+ STATUS_REG_OFS) + 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;
+
+ 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)
+{
+ 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, ow_reg_add(map, PFOW_QUERY_STRING_P));
+ pfow_val[1] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_F));
+ pfow_val[2] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_O));
+ pfow_val[3] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_W));
+
+ /* 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;
+
+ mutex_lock(&lpdd2_nvm_mutex);
+
+ *retlen = len;
+
+ map_copy_from(map, buf, start_add, *retlen);
+
+ mutex_unlock(&lpdd2_nvm_mutex);
+ return 0;
+}
+
+/*
+ * 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;
+
+ 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)
+{
+ struct map_info *map;
+ struct mtd_info *mtd;
+ struct resource *add_range;
+ struct resource *control_regs;
+ struct pcm_int_data *pcm_data;
+
+ /* Allocate memory control_regs data structures */
+ pcm_data = devm_kzalloc(&pdev->dev, sizeof(*pcm_data), GFP_KERNEL);
+ if (!pcm_data)
+ return -ENOMEM;
+
+ pcm_data->bus_width = BUS_WIDTH;
+
+ /* Allocate memory for map_info & mtd_info data structures */
+ map = devm_kzalloc(&pdev->dev, sizeof(*map), GFP_KERNEL);
+ if (!map)
+ return -ENOMEM;
+
+ mtd = devm_kzalloc(&pdev->dev, sizeof(*mtd), GFP_KERNEL);
+ if (!mtd)
+ return -ENOMEM;
+
+ /* lpddr2_nvm address range */
+ add_range = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ /* Populate map_info data structure */
+ *map = (struct map_info) {
+ .virt = devm_ioremap_resource(&pdev->dev, add_range),
+ .name = pdev->dev.init_name,
+ .phys = add_range->start,
+ .size = resource_size(add_range),
+ .bankwidth = pcm_data->bus_width / 2,
+ .pfow_base = OW_BASE_ADDRESS,
+ .fldrv_priv = pcm_data,
+ };
+ if (IS_ERR(map->virt))
+ return PTR_ERR(map->virt);
+
+ simple_map_init(map); /* fill with default methods */
+
+ control_regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ pcm_data->ctl_regs = devm_ioremap_resource(&pdev->dev, control_regs);
+ if (IS_ERR(pcm_data->ctl_regs))
+ return PTR_ERR(pcm_data->ctl_regs);
+
+ /* Populate mtd_info data structure */
+ *mtd = (struct mtd_info) {
+ .name = pdev->dev.init_name,
+ .type = MTD_RAM,
+ .priv = map,
+ .size = resource_size(add_range),
+ .erasesize = ERASE_BLOCKSIZE * pcm_data->bus_width,
+ .writesize = 1,
+ .writebufsize = WRITE_BUFFSIZE * pcm_data->bus_width,
+ .flags = (MTD_CAP_NVRAM | MTD_POWERUP_LOCK),
+ ._read = lpddr2_nvm_read,
+ ._write = lpddr2_nvm_write,
+ ._erase = lpddr2_nvm_erase,
+ ._unlock = lpddr2_nvm_unlock,
+ ._lock = lpddr2_nvm_lock,
+ };
+
+ /* Verify the presence of the device looking for PFOW string */
+ if (!lpddr2_nvm_pfow_present(map)) {
+ pr_err("device not recognized\n");
+ return -EINVAL;
+ }
+ /* Parse partitions and register the MTD device */
+ return mtd_device_parse_register(mtd, NULL, NULL, NULL, 0);
+}
+
+/*
+ * lpddr2_nvm driver remove method
+ */
+static int lpddr2_nvm_remove(struct platform_device *pdev)
+{
+ return mtd_device_unregister(dev_get_drvdata(&pdev->dev));
+}
+
+/* Initialize platform_driver data structure for lpddr2_nvm */
+static struct platform_driver lpddr2_nvm_drv = {
+ .driver = {
+ .name = "lpddr2_nvm",
+ },
+ .probe = lpddr2_nvm_probe,
+ .remove = lpddr2_nvm_remove,
+};
+
+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 e272ea0..763bb69 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_NVRAM (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)
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