// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2017 Free Electrons
* Copyright (C) 2017 NextThing Co
*
* Author: Boris Brezillon <boris.brezillon@free-electrons.com>
*/
#include <linux/sizes.h>
#include <linux/slab.h>
#include "internals.h"
#define NAND_HYNIX_CMD_SET_PARAMS 0x36
#define NAND_HYNIX_CMD_APPLY_PARAMS 0x16
#define NAND_HYNIX_1XNM_RR_REPEAT 8
/**
* struct hynix_read_retry - read-retry data
* @nregs: number of register to set when applying a new read-retry mode
* @regs: register offsets (NAND chip dependent)
* @values: array of values to set in registers. The array size is equal to
* (nregs * nmodes)
*/
struct hynix_read_retry {
int nregs;
const u8 *regs;
u8 values[0];
};
/**
* struct hynix_nand - private Hynix NAND struct
* @nand_technology: manufacturing process expressed in picometer
* @read_retry: read-retry information
*/
struct hynix_nand {
const struct hynix_read_retry *read_retry;
};
/**
* struct hynix_read_retry_otp - structure describing how the read-retry OTP
* area
* @nregs: number of hynix private registers to set before reading the reading
* the OTP area
* @regs: registers that should be configured
* @values: values that should be set in regs
* @page: the address to pass to the READ_PAGE command. Depends on the NAND
* chip
* @size: size of the read-retry OTP section
*/
struct hynix_read_retry_otp {
int nregs;
const u8 *regs;
const u8 *values;
int page;
int size;
};
static bool hynix_nand_has_valid_jedecid(struct nand_chip *chip)
{
u8 jedecid[5] = { };
int ret;
ret = nand_readid_op(chip, 0x40, jedecid, sizeof(jedecid));
if (ret)
return false;
return !strncmp("JEDEC", jedecid, sizeof(jedecid));
}
static int hynix_nand_cmd_op(struct nand_chip *chip, u8 cmd)
{
if (nand_has_exec_op(chip)) {
struct nand_op_instr instrs[] = {
NAND_OP_CMD(cmd, 0),
};
struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
return nand_exec_op(chip, &op);
}
chip->legacy.cmdfunc(chip, cmd, -1, -1);
return 0;
}
static int hynix_nand_reg_write_op(struct nand_chip *chip, u8 addr, u8 val)
{
u16 column = ((u16)addr << 8) | addr;
if (nand_has_exec_op(chip)) {
struct nand_op_instr instrs[] = {
NAND_OP_ADDR(1, &addr, 0),
NAND_OP_8BIT_DATA_OUT(1, &val, 0),
};
struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs);
return nand_exec_op(chip, &op);
}
chip->legacy.cmdfunc(chip, NAND_CMD_NONE, column, -1);
chip->legacy.write_byte(chip, val);
return 0;
}
static int hynix_nand_setup_read_retry(struct nand_chip *chip, int retry_mode)
{
struct hynix_nand *hynix = nand_get_manufacturer_data(chip);
const u8 *values;
int i, ret;
values = hynix->read_retry->values +
(retry_mode * hynix->read_retry->nregs);
/* Enter 'Set Hynix Parameters' mode */
ret = hynix_nand_cmd_op(chip, NAND_HYNIX_CMD_SET_PARAMS);
if (ret)
return ret;
/*
* Configure the NAND in the requested read-retry mode.
* This is done by setting pre-defined values in internal NAND
* registers.
*
* The set of registers is NAND specific, and the values are either
* predefined or extracted from an OTP area on the NAND (values are
* probably tweaked at production in this case).
*/
for (i = 0; i < hynix->read_retry->nregs; i++) {
ret = hynix_nand_reg_write_op(chip, hynix->read_retry->regs[i],
values[i]);
if (ret)
return ret;
}
/* Apply the new settings. */
return hynix_nand_cmd_op(chip, NAND_HYNIX_CMD_APPLY_PARAMS);
}
/**
* hynix_get_majority - get the value that is occurring the most in a given
* set of values
* @in: the array of values to test
* @repeat: the size of the in array
* @out: pointer used to store the output value
*
* This function implements the 'majority check' logic that is supposed to
* overcome the unreliability of MLC NANDs when reading the OTP area storing
* the read-retry parameters.
*
* It's based on a pretty simple assumption: if we repeat the same value
* several times and then take the one that is occurring the most, we should
* find the correct value.
* Let's hope this dummy algorithm prevents us from losing the read-retry
* parameters.
*/
static int hynix_get_majority(const u8 *in, int repeat, u8 *out)
{
int i, j, half = repeat / 2;
/*
* We only test the first half of the in array because we must ensure
* that the value is at least occurring repeat / 2 times.
*
* This loop is suboptimal since we may count the occurrences of the
* same value several time, but we are doing that on small sets, which
* makes it acceptable.
*/
for (i = 0; i < half; i++) {
int cnt = 0;
u8 val = in[i];
/* Count all values that are matching the one at index i. */
for (j = i + 1; j < repeat; j++) {
if (in[j] == val)
cnt++;
}
/* We found a value occurring more than repeat / 2. */
if (cnt > half) {
*out = val;
return 0;
}
}
return -EIO;
}
static int hynix_read_rr_otp(struct nand_chip *chip,
const struct hynix_read_retry_otp *info,
void *buf)
{
int i, ret;
ret = nand_reset_op(chip);
if (ret)
return ret;
ret = hynix_nand_cmd_op(chip, NAND_HYNIX_CMD_SET_PARAMS);
if (ret)
return ret;
for (i = 0; i < info->nregs; i++) {
ret = hynix_nand_reg_write_op(chip, info->regs[i],
info->values[i]);
if (ret)
return ret;
}
ret = hynix_nand_cmd_op(chip, NAND_HYNIX_CMD_APPLY_PARAMS);
if (ret)
return ret;
/* Sequence to enter OTP mode? */
ret = hynix_nand_cmd_op(chip, 0x17);
if (ret)
return ret;
ret = hynix_nand_cmd_op(chip, 0x4);
if (ret)
return ret;
ret = hynix_nand_cmd_op(chip, 0x19);
if (ret)
return ret;
/* Now read the page */
ret = nand_read_page_op(chip, info->page, 0, buf, info->size);
if (ret)
return ret;
/* Put everything back to normal */
ret = nand_reset_op(chip);
if (ret)
return ret;
ret = hynix_nand_cmd_op(chip, NAND_HYNIX_CMD_SET_PARAMS);
if (ret)
return ret;
ret = hynix_nand_reg_write_op(chip, 0x38, 0);
if (ret)
return ret;
ret = hynix_nand_cmd_op(chip, NAND_HYNIX_CMD_APPLY_PARAMS);
if (ret)
return ret;
return nand_read_page_op(chip, 0, 0, NULL, 0);
}
#define NAND_HYNIX_1XNM_RR_COUNT_OFFS 0
#define NAND_HYNIX_1XNM_RR_REG_COUNT_OFFS 8
#define NAND_HYNIX_1XNM_RR_SET_OFFS(x, setsize, inv) \
(16 + ((((x) * 2) + ((inv) ? 1 : 0)) * (setsize)))
static int hynix_mlc_1xnm_rr_value(const u8 *buf, int nmodes, int nregs,
int mode, int reg, bool inv, u8 *val)
{
u8 tmp[NAND_HYNIX_1XNM_RR_REPEAT];
int val_offs = (mode * nregs) + reg;
int set_size = nmodes * nregs;
int i, ret;
for (i = 0; i < NAND_HYNIX_1XNM_RR_REPEAT; i++) {
int set_offs = NAND_HYNIX_1XNM_RR_SET_OFFS(i, set_size, inv);
tmp[i] = buf[val_offs + set_offs];
}
ret = hynix_get_majority(tmp, NAND_HYNIX_1XNM_RR_REPEAT, val);
if (ret)
return ret;
if (inv)
*val = ~*val;
return 0;
}
static u8 hynix_1xnm_mlc_read_retry_regs[] = {
0xcc, 0xbf, 0xaa, 0xab, 0xcd, 0xad, 0xae, 0xaf
};
static int hynix_mlc_1xnm_rr_init(struct nand_chip *chip,
const struct hynix_read_retry_otp *info)
{
struct hynix_nand *hynix = nand_get_manufacturer_data(chip);
struct hynix_read_retry *rr = NULL;
int ret, i, j;
u8 nregs, nmodes;
u8 *buf;
buf = kmalloc(info->size, GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = hynix_read_rr_otp(chip, info, buf);
if (ret)
goto out;
ret = hynix_get_majority(buf, NAND_HYNIX_1XNM_RR_REPEAT,
&nmodes);
if (ret)
goto out;
ret = hynix_get_majority(buf + NAND_HYNIX_1XNM_RR_REPEAT,
NAND_HYNIX_1XNM_RR_REPEAT,
&nregs);
if (ret)
goto out;
rr = kzalloc(sizeof(*rr) + (nregs * nmodes), GFP_KERNEL);
if (!rr) {
ret = -ENOMEM;
goto out;
}
for (i = 0; i < nmodes; i++) {
for (j = 0; j < nregs; j++) {
u8 *val = rr->values + (i * nregs);
ret = hynix_mlc_1xnm_rr_value(buf, nmodes, nregs, i, j,
false, val);
if (!ret)
continue;
ret = hynix_mlc_1xnm_rr_value(buf, nmodes, nregs, i, j,
true, val);
if (ret)
goto out;
}
}
rr->nregs = nregs;
rr->regs = hynix_1xnm_mlc_read_retry_regs;
hynix->read_retry = rr;
chip->setup_read_retry = hynix_nand_setup_read_retry;
chip->read_retries = nmodes;
out:
kfree(buf);
if (ret)
kfree(rr);
return ret;
}
static const u8 hynix_mlc_1xnm_rr_otp_regs[] = { 0x38 };
static const u8 hynix_mlc_1xnm_rr_otp_values[] = { 0x52 };
static const struct hynix_read_retry_otp hynix_mlc_1xnm_rr_otps[] = {
{
.nregs = ARRAY_SIZE(hynix_mlc_1xnm_rr_otp_regs),
.regs = hynix_mlc_1xnm_rr_otp_regs,
.values = hynix_mlc_1xnm_rr_otp_values,
.page = 0x21f,
.size = 784
},
{
.nregs = ARRAY_SIZE(hynix_mlc_1xnm_rr_otp_regs),
.regs = hynix_mlc_1xnm_rr_otp_regs,
.values = hynix_mlc_1xnm_rr_otp_values,
.page = 0x200,
.size = 528,
},
};
static int hynix_nand_rr_init(struct nand_chip *chip)
{
int i, ret = 0;
bool valid_jedecid;
valid_jedecid = hynix_nand_has_valid_jedecid(chip);
/*
* We only support read-retry for 1xnm NANDs, and those NANDs all
* expose a valid JEDEC ID.
*/
if (valid_jedecid) {
u8 nand_tech = chip->id.data[5] >> 4;
/* 1xnm technology */
if (nand_tech == 4) {
for (i = 0; i < ARRAY_SIZE(hynix_mlc_1xnm_rr_otps);
i++) {
/*
* FIXME: Hynix recommend to copy the
* read-retry OTP area into a normal page.
*/
ret = hynix_mlc_1xnm_rr_init(chip,
hynix_mlc_1xnm_rr_otps);
if (!ret)
break;
}
}
}
if (ret)
pr_warn("failed to initialize read-retry infrastructure");
return 0;
}
static void hynix_nand_extract_oobsize(struct nand_chip *chip,
bool valid_jedecid)
{
struct mtd_info *mtd = nand_to_mtd(chip);
struct nand_memory_organization *memorg;
u8 oobsize;
memorg = nanddev_get_memorg(&chip->base);
oobsize = ((chip->id.data[3] >> 2) & 0x3) |
((chip->id.data[3] >> 4) & 0x4);
if (valid_jedecid) {
switch (oobsize) {
case 0:
memorg->oobsize = 2048;
break;
case 1:
memorg->oobsize = 1664;
break;
case 2:
memorg->oobsize = 1024;
break;
case 3:
memorg->oobsize = 640;
break;
default:
/*
* We should never reach this case, but if that
* happens, this probably means Hynix decided to use
* a different extended ID format, and we should find
* a way to support it.
*/
WARN(1, "Invalid OOB size");
break;
}
} else {
switch (oobsize) {
case 0:
memorg->oobsize = 128;
break;
case 1:
memorg->oobsize = 224;
break;
case 2:
memorg->oobsize = 448;
break;
case 3:
memorg->oobsize = 64;
break;
case 4:
memorg->oobsize = 32;
break;
case 5:
memorg->oobsize = 16;
break;
case 6:
memorg->oobsize = 640;
break;
default:
/*
* We should never reach this case, but if that
* happens, this probably means Hynix decided to use
* a different extended ID format, and we should find
* a way to support it.
*/
WARN(1, "Invalid OOB size");
break;
}
/*
* The datasheet of H27UCG8T2BTR mentions that the "Redundant
* Area Size" is encoded "per 8KB" (page size). This chip uses
* a page size of 16KiB. The datasheet mentions an OOB size of
* 1.280 bytes, but the OOB size encoded in the ID bytes (using
* the existing logic above) is 640 bytes.
* Update the OOB size for this chip by taking the value
* determined above and scaling it to the actual page size (so
* the actual OOB size for this chip is: 640 * 16k / 8k).
*/
if (chip->id.data[1] == 0xde)
memorg->oobsize *= memorg->pagesize / SZ_8K;
}
mtd->oobsize = memorg->oobsize;
}
static void hynix_nand_extract_ecc_requirements(struct nand_chip *chip,
bool valid_jedecid)
{
u8 ecc_level = (chip->id.data[4] >> 4) & 0x7;
if (valid_jedecid) {
/* Reference: H27UCG8T2E datasheet */
chip->base.eccreq.step_size = 1024;
switch (ecc_level) {
case 0:
chip->base.eccreq.step_size = 0;
chip->base.eccreq.strength = 0;
break;
case 1:
chip->base.eccreq.strength = 4;
break;
case 2:
chip->base.eccreq.strength = 24;
break;
case 3:
chip->base.eccreq.strength = 32;
break;
case 4:
chip->base.eccreq.strength = 40;
break;
case 5:
chip->base.eccreq.strength = 50;
break;
case 6:
chip->base.eccreq.strength = 60;
break;
default:
/*
* We should never reach this case, but if that
* happens, this probably means Hynix decided to use
* a different extended ID format, and we should find
* a way to support it.
*/
WARN(1, "Invalid ECC requirements");
}
} else {
/*
* The ECC requirements field meaning depends on the
* NAND technology.
*/
u8 nand_tech = chip->id.data[5] & 0x7;
if (nand_tech < 3) {
/* > 26nm, reference: H27UBG8T2A datasheet */
if (ecc_level < 5) {
chip->base.eccreq.step_size = 512;
chip->base.eccreq.strength = 1 << ecc_level;
} else if (ecc_level < 7) {
if (ecc_level == 5)
chip->base.eccreq.step_size = 2048;
else
chip->base.eccreq.step_size = 1024;
chip->base.eccreq.strength = 24;
} else {
/*
* We should never reach this case, but if that
* happens, this probably means Hynix decided
* to use a different extended ID format, and
* we should find a way to support it.
*/
WARN(1, "Invalid ECC requirements");
}
} else {
/* <= 26nm, reference: H27UBG8T2B datasheet */
if (!ecc_level) {
chip->base.eccreq.step_size = 0;
chip->base.eccreq.strength = 0;
} else if (ecc_level < 5) {
chip->base.eccreq.step_size = 512;
chip->base.eccreq.strength = 1 << (ecc_level - 1);
} else {
chip->base.eccreq.step_size = 1024;
chip->base.eccreq.strength = 24 +
(8 * (ecc_level - 5));
}
}
}
}
static void hynix_nand_extract_scrambling_requirements(struct nand_chip *chip,
bool valid_jedecid)
{
u8 nand_tech;
/* We need scrambling on all TLC NANDs*/
if (nanddev_bits_per_cell(&chip->base) > 2)
chip->options |= NAND_NEED_SCRAMBLING;
/* And on MLC NANDs with sub-3xnm process */
if (valid_jedecid) {
nand_tech = chip->id.data[5] >> 4;
/* < 3xnm */
if (nand_tech > 0)
chip->options |= NAND_NEED_SCRAMBLING;
} else {
nand_tech = chip->id.data[5] & 0x7;
/* < 32nm */
if (nand_tech > 2)
chip->options |= NAND_NEED_SCRAMBLING;
}
}
static void hynix_nand_decode_id(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
struct nand_memory_organization *memorg;
bool valid_jedecid;
u8 tmp;
memorg = nanddev_get_memorg(&chip->base);
/*
* Exclude all SLC NANDs from this advanced detection scheme.
* According to the ranges defined in several datasheets, it might
* appear that even SLC NANDs could fall in this extended ID scheme.
* If that the case rework the test to let SLC NANDs go through the
* detection process.
*/
if (chip->id.len < 6 || nand_is_slc(chip)) {
nand_decode_ext_id(chip);
return;
}
/* Extract pagesize */
memorg->pagesize = 2048 << (chip->id.data[3] & 0x03);
mtd->writesize = memorg->pagesize;
tmp = (chip->id.data[3] >> 4) & 0x3;
/*
* When bit7 is set that means we start counting at 1MiB, otherwise
* we start counting at 128KiB and shift this value the content of
* ID[3][4:5].
* The only exception is when ID[3][4:5] == 3 and ID[3][7] == 0, in
* this case the erasesize is set to 768KiB.
*/
if (chip->id.data[3] & 0x80) {
memorg->pages_per_eraseblock = (SZ_1M << tmp) /
memorg->pagesize;
mtd->erasesize = SZ_1M << tmp;
} else if (tmp == 3) {
memorg->pages_per_eraseblock = (SZ_512K + SZ_256K) /
memorg->pagesize;
mtd->erasesize = SZ_512K + SZ_256K;
} else {
memorg->pages_per_eraseblock = (SZ_128K << tmp) /
memorg->pagesize;
mtd->erasesize = SZ_128K << tmp;
}
/*
* Modern Toggle DDR NANDs have a valid JEDECID even though they are
* not exposing a valid JEDEC parameter table.
* These NANDs use a different NAND ID scheme.
*/
valid_jedecid = hynix_nand_has_valid_jedecid(chip);
hynix_nand_extract_oobsize(chip, valid_jedecid);
hynix_nand_extract_ecc_requirements(chip, valid_jedecid);
hynix_nand_extract_scrambling_requirements(chip, valid_jedecid);
}
static void hynix_nand_cleanup(struct nand_chip *chip)
{
struct hynix_nand *hynix = nand_get_manufacturer_data(chip);
if (!hynix)
return;
kfree(hynix->read_retry);
kfree(hynix);
nand_set_manufacturer_data(chip, NULL);
}
static int hynix_nand_init(struct nand_chip *chip)
{
struct hynix_nand *hynix;
int ret;
if (!nand_is_slc(chip))
chip->options |= NAND_BBM_LASTPAGE;
else
chip->options |= NAND_BBM_FIRSTPAGE | NAND_BBM_SECONDPAGE;
hynix = kzalloc(sizeof(*hynix), GFP_KERNEL);
if (!hynix)
return -ENOMEM;
nand_set_manufacturer_data(chip, hynix);
ret = hynix_nand_rr_init(chip);
if (ret)
hynix_nand_cleanup(chip);
return ret;
}
const struct nand_manufacturer_ops hynix_nand_manuf_ops = {
.detect = hynix_nand_decode_id,
.init = hynix_nand_init,
.cleanup = hynix_nand_cleanup,
};