diff options
Diffstat (limited to 'drivers/mtd/lpddr/lpddr2_nvm.c')
| -rw-r--r-- | drivers/mtd/lpddr/lpddr2_nvm.c | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/drivers/mtd/lpddr/lpddr2_nvm.c b/drivers/mtd/lpddr/lpddr2_nvm.c new file mode 100644 index 000000000..90e6cb64d --- /dev/null +++ b/drivers/mtd/lpddr/lpddr2_nvm.c @@ -0,0 +1,505 @@ +/* + * 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@gmail.com> + * Domenico Manna <domenico.manna@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) +{ + return lpddr2_nvm_do_block_op(mtd, instr->addr, instr->len, + LPDDR2_NVM_ERASE); +} + +/* + * 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); +} + +static const struct mtd_info lpddr2_nvm_mtd_info = { + .type = MTD_RAM, + .writesize = 1, + .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, +}; + +/* + * 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 = lpddr2_nvm_mtd_info; + mtd->dev.parent = &pdev->dev; + mtd->name = pdev->dev.init_name; + mtd->priv = map; + mtd->size = resource_size(add_range); + mtd->erasesize = ERASE_BLOCKSIZE * pcm_data->bus_width; + mtd->writebufsize = WRITE_BUFFSIZE * pcm_data->bus_width; + + /* 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_register(mtd, 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@gmail.com>"); +MODULE_DESCRIPTION("MTD driver for LPDDR2-NVM PCM memories"); 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