- 根目录:
- drivers
- mtd
- lpddr
- lpddr2_nvm.c
/*
* 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)
{
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) {
.dev = { .parent = &pdev->dev },
.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@gmail.com>");
MODULE_DESCRIPTION("MTD driver for LPDDR2-NVM PCM memories");