linux_dsm_epyc7002/drivers/mtd/nand/raw/nand_legacy.c
Mathieu Malaterre 5b15f8650b mtd: rawnand: Annotate implicit fall through in nand_command/nand_command_lp
There is a plan to build the kernel with -Wimplicit-fallthrough and
these places in the code produced warnings (W=1).

This commit removes the following warnings:

  drivers/mtd/nand/raw/nand_legacy.c:332:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
  drivers/mtd/nand/raw/nand_legacy.c:483:3: warning: this statement may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2019-02-05 16:56:10 +01:00

641 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
* 2002-2006 Thomas Gleixner (tglx@linutronix.de)
*
* Credits:
* David Woodhouse for adding multichip support
*
* Aleph One Ltd. and Toby Churchill Ltd. for supporting the
* rework for 2K page size chips
*
* This file contains all legacy helpers/code that should be removed
* at some point.
*/
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/nmi.h>
#include "internals.h"
/**
* nand_read_byte - [DEFAULT] read one byte from the chip
* @chip: NAND chip object
*
* Default read function for 8bit buswidth
*/
static uint8_t nand_read_byte(struct nand_chip *chip)
{
return readb(chip->legacy.IO_ADDR_R);
}
/**
* nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
* @chip: NAND chip object
*
* Default read function for 16bit buswidth with endianness conversion.
*
*/
static uint8_t nand_read_byte16(struct nand_chip *chip)
{
return (uint8_t) cpu_to_le16(readw(chip->legacy.IO_ADDR_R));
}
/**
* nand_select_chip - [DEFAULT] control CE line
* @chip: NAND chip object
* @chipnr: chipnumber to select, -1 for deselect
*
* Default select function for 1 chip devices.
*/
static void nand_select_chip(struct nand_chip *chip, int chipnr)
{
switch (chipnr) {
case -1:
chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
0 | NAND_CTRL_CHANGE);
break;
case 0:
break;
default:
BUG();
}
}
/**
* nand_write_byte - [DEFAULT] write single byte to chip
* @chip: NAND chip object
* @byte: value to write
*
* Default function to write a byte to I/O[7:0]
*/
static void nand_write_byte(struct nand_chip *chip, uint8_t byte)
{
chip->legacy.write_buf(chip, &byte, 1);
}
/**
* nand_write_byte16 - [DEFAULT] write single byte to a chip with width 16
* @chip: NAND chip object
* @byte: value to write
*
* Default function to write a byte to I/O[7:0] on a 16-bit wide chip.
*/
static void nand_write_byte16(struct nand_chip *chip, uint8_t byte)
{
uint16_t word = byte;
/*
* It's not entirely clear what should happen to I/O[15:8] when writing
* a byte. The ONFi spec (Revision 3.1; 2012-09-19, Section 2.16) reads:
*
* When the host supports a 16-bit bus width, only data is
* transferred at the 16-bit width. All address and command line
* transfers shall use only the lower 8-bits of the data bus. During
* command transfers, the host may place any value on the upper
* 8-bits of the data bus. During address transfers, the host shall
* set the upper 8-bits of the data bus to 00h.
*
* One user of the write_byte callback is nand_set_features. The
* four parameters are specified to be written to I/O[7:0], but this is
* neither an address nor a command transfer. Let's assume a 0 on the
* upper I/O lines is OK.
*/
chip->legacy.write_buf(chip, (uint8_t *)&word, 2);
}
/**
* nand_write_buf - [DEFAULT] write buffer to chip
* @chip: NAND chip object
* @buf: data buffer
* @len: number of bytes to write
*
* Default write function for 8bit buswidth.
*/
static void nand_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
{
iowrite8_rep(chip->legacy.IO_ADDR_W, buf, len);
}
/**
* nand_read_buf - [DEFAULT] read chip data into buffer
* @chip: NAND chip object
* @buf: buffer to store date
* @len: number of bytes to read
*
* Default read function for 8bit buswidth.
*/
static void nand_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
{
ioread8_rep(chip->legacy.IO_ADDR_R, buf, len);
}
/**
* nand_write_buf16 - [DEFAULT] write buffer to chip
* @chip: NAND chip object
* @buf: data buffer
* @len: number of bytes to write
*
* Default write function for 16bit buswidth.
*/
static void nand_write_buf16(struct nand_chip *chip, const uint8_t *buf,
int len)
{
u16 *p = (u16 *) buf;
iowrite16_rep(chip->legacy.IO_ADDR_W, p, len >> 1);
}
/**
* nand_read_buf16 - [DEFAULT] read chip data into buffer
* @chip: NAND chip object
* @buf: buffer to store date
* @len: number of bytes to read
*
* Default read function for 16bit buswidth.
*/
static void nand_read_buf16(struct nand_chip *chip, uint8_t *buf, int len)
{
u16 *p = (u16 *) buf;
ioread16_rep(chip->legacy.IO_ADDR_R, p, len >> 1);
}
/**
* panic_nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
* @chip: NAND chip object
* @timeo: Timeout
*
* Helper function for nand_wait_ready used when needing to wait in interrupt
* context.
*/
static void panic_nand_wait_ready(struct nand_chip *chip, unsigned long timeo)
{
int i;
/* Wait for the device to get ready */
for (i = 0; i < timeo; i++) {
if (chip->legacy.dev_ready(chip))
break;
touch_softlockup_watchdog();
mdelay(1);
}
}
/**
* nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
* @chip: NAND chip object
*
* Wait for the ready pin after a command, and warn if a timeout occurs.
*/
void nand_wait_ready(struct nand_chip *chip)
{
unsigned long timeo = 400;
if (in_interrupt() || oops_in_progress)
return panic_nand_wait_ready(chip, timeo);
/* Wait until command is processed or timeout occurs */
timeo = jiffies + msecs_to_jiffies(timeo);
do {
if (chip->legacy.dev_ready(chip))
return;
cond_resched();
} while (time_before(jiffies, timeo));
if (!chip->legacy.dev_ready(chip))
pr_warn_ratelimited("timeout while waiting for chip to become ready\n");
}
EXPORT_SYMBOL_GPL(nand_wait_ready);
/**
* nand_wait_status_ready - [GENERIC] Wait for the ready status after commands.
* @chip: NAND chip object
* @timeo: Timeout in ms
*
* Wait for status ready (i.e. command done) or timeout.
*/
static void nand_wait_status_ready(struct nand_chip *chip, unsigned long timeo)
{
int ret;
timeo = jiffies + msecs_to_jiffies(timeo);
do {
u8 status;
ret = nand_read_data_op(chip, &status, sizeof(status), true);
if (ret)
return;
if (status & NAND_STATUS_READY)
break;
touch_softlockup_watchdog();
} while (time_before(jiffies, timeo));
};
/**
* nand_command - [DEFAULT] Send command to NAND device
* @chip: NAND chip object
* @command: the command to be sent
* @column: the column address for this command, -1 if none
* @page_addr: the page address for this command, -1 if none
*
* Send command to NAND device. This function is used for small page devices
* (512 Bytes per page).
*/
static void nand_command(struct nand_chip *chip, unsigned int command,
int column, int page_addr)
{
struct mtd_info *mtd = nand_to_mtd(chip);
int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
/* Write out the command to the device */
if (command == NAND_CMD_SEQIN) {
int readcmd;
if (column >= mtd->writesize) {
/* OOB area */
column -= mtd->writesize;
readcmd = NAND_CMD_READOOB;
} else if (column < 256) {
/* First 256 bytes --> READ0 */
readcmd = NAND_CMD_READ0;
} else {
column -= 256;
readcmd = NAND_CMD_READ1;
}
chip->legacy.cmd_ctrl(chip, readcmd, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
}
if (command != NAND_CMD_NONE)
chip->legacy.cmd_ctrl(chip, command, ctrl);
/* Address cycle, when necessary */
ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
/* Serially input address */
if (column != -1) {
/* Adjust columns for 16 bit buswidth */
if (chip->options & NAND_BUSWIDTH_16 &&
!nand_opcode_8bits(command))
column >>= 1;
chip->legacy.cmd_ctrl(chip, column, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
}
if (page_addr != -1) {
chip->legacy.cmd_ctrl(chip, page_addr, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
chip->legacy.cmd_ctrl(chip, page_addr >> 8, ctrl);
if (chip->options & NAND_ROW_ADDR_3)
chip->legacy.cmd_ctrl(chip, page_addr >> 16, ctrl);
}
chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
/*
* Program and erase have their own busy handlers status and sequential
* in needs no delay
*/
switch (command) {
case NAND_CMD_NONE:
case NAND_CMD_PAGEPROG:
case NAND_CMD_ERASE1:
case NAND_CMD_ERASE2:
case NAND_CMD_SEQIN:
case NAND_CMD_STATUS:
case NAND_CMD_READID:
case NAND_CMD_SET_FEATURES:
return;
case NAND_CMD_RESET:
if (chip->legacy.dev_ready)
break;
udelay(chip->legacy.chip_delay);
chip->legacy.cmd_ctrl(chip, NAND_CMD_STATUS,
NAND_CTRL_CLE | NAND_CTRL_CHANGE);
chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
/* EZ-NAND can take upto 250ms as per ONFi v4.0 */
nand_wait_status_ready(chip, 250);
return;
/* This applies to read commands */
case NAND_CMD_READ0:
/*
* READ0 is sometimes used to exit GET STATUS mode. When this
* is the case no address cycles are requested, and we can use
* this information to detect that we should not wait for the
* device to be ready.
*/
if (column == -1 && page_addr == -1)
return;
/* fall through */
default:
/*
* If we don't have access to the busy pin, we apply the given
* command delay
*/
if (!chip->legacy.dev_ready) {
udelay(chip->legacy.chip_delay);
return;
}
}
/*
* Apply this short delay always to ensure that we do wait tWB in
* any case on any machine.
*/
ndelay(100);
nand_wait_ready(chip);
}
static void nand_ccs_delay(struct nand_chip *chip)
{
/*
* The controller already takes care of waiting for tCCS when the RNDIN
* or RNDOUT command is sent, return directly.
*/
if (!(chip->options & NAND_WAIT_TCCS))
return;
/*
* Wait tCCS_min if it is correctly defined, otherwise wait 500ns
* (which should be safe for all NANDs).
*/
if (nand_has_setup_data_iface(chip))
ndelay(chip->data_interface.timings.sdr.tCCS_min / 1000);
else
ndelay(500);
}
/**
* nand_command_lp - [DEFAULT] Send command to NAND large page device
* @chip: NAND chip object
* @command: the command to be sent
* @column: the column address for this command, -1 if none
* @page_addr: the page address for this command, -1 if none
*
* Send command to NAND device. This is the version for the new large page
* devices. We don't have the separate regions as we have in the small page
* devices. We must emulate NAND_CMD_READOOB to keep the code compatible.
*/
static void nand_command_lp(struct nand_chip *chip, unsigned int command,
int column, int page_addr)
{
struct mtd_info *mtd = nand_to_mtd(chip);
/* Emulate NAND_CMD_READOOB */
if (command == NAND_CMD_READOOB) {
column += mtd->writesize;
command = NAND_CMD_READ0;
}
/* Command latch cycle */
if (command != NAND_CMD_NONE)
chip->legacy.cmd_ctrl(chip, command,
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
if (column != -1 || page_addr != -1) {
int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
/* Serially input address */
if (column != -1) {
/* Adjust columns for 16 bit buswidth */
if (chip->options & NAND_BUSWIDTH_16 &&
!nand_opcode_8bits(command))
column >>= 1;
chip->legacy.cmd_ctrl(chip, column, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
/* Only output a single addr cycle for 8bits opcodes. */
if (!nand_opcode_8bits(command))
chip->legacy.cmd_ctrl(chip, column >> 8, ctrl);
}
if (page_addr != -1) {
chip->legacy.cmd_ctrl(chip, page_addr, ctrl);
chip->legacy.cmd_ctrl(chip, page_addr >> 8,
NAND_NCE | NAND_ALE);
if (chip->options & NAND_ROW_ADDR_3)
chip->legacy.cmd_ctrl(chip, page_addr >> 16,
NAND_NCE | NAND_ALE);
}
}
chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
/*
* Program and erase have their own busy handlers status, sequential
* in and status need no delay.
*/
switch (command) {
case NAND_CMD_NONE:
case NAND_CMD_CACHEDPROG:
case NAND_CMD_PAGEPROG:
case NAND_CMD_ERASE1:
case NAND_CMD_ERASE2:
case NAND_CMD_SEQIN:
case NAND_CMD_STATUS:
case NAND_CMD_READID:
case NAND_CMD_SET_FEATURES:
return;
case NAND_CMD_RNDIN:
nand_ccs_delay(chip);
return;
case NAND_CMD_RESET:
if (chip->legacy.dev_ready)
break;
udelay(chip->legacy.chip_delay);
chip->legacy.cmd_ctrl(chip, NAND_CMD_STATUS,
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
/* EZ-NAND can take upto 250ms as per ONFi v4.0 */
nand_wait_status_ready(chip, 250);
return;
case NAND_CMD_RNDOUT:
/* No ready / busy check necessary */
chip->legacy.cmd_ctrl(chip, NAND_CMD_RNDOUTSTART,
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
nand_ccs_delay(chip);
return;
case NAND_CMD_READ0:
/*
* READ0 is sometimes used to exit GET STATUS mode. When this
* is the case no address cycles are requested, and we can use
* this information to detect that READSTART should not be
* issued.
*/
if (column == -1 && page_addr == -1)
return;
chip->legacy.cmd_ctrl(chip, NAND_CMD_READSTART,
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
/* fall through - This applies to read commands */
default:
/*
* If we don't have access to the busy pin, we apply the given
* command delay.
*/
if (!chip->legacy.dev_ready) {
udelay(chip->legacy.chip_delay);
return;
}
}
/*
* Apply this short delay always to ensure that we do wait tWB in
* any case on any machine.
*/
ndelay(100);
nand_wait_ready(chip);
}
/**
* nand_get_set_features_notsupp - set/get features stub returning -ENOTSUPP
* @chip: nand chip info structure
* @addr: feature address.
* @subfeature_param: the subfeature parameters, a four bytes array.
*
* Should be used by NAND controller drivers that do not support the SET/GET
* FEATURES operations.
*/
int nand_get_set_features_notsupp(struct nand_chip *chip, int addr,
u8 *subfeature_param)
{
return -ENOTSUPP;
}
EXPORT_SYMBOL(nand_get_set_features_notsupp);
/**
* nand_wait - [DEFAULT] wait until the command is done
* @chip: NAND chip structure
*
* Wait for command done. This applies to erase and program only.
*/
static int nand_wait(struct nand_chip *chip)
{
unsigned long timeo = 400;
u8 status;
int ret;
/*
* Apply this short delay always to ensure that we do wait tWB in any
* case on any machine.
*/
ndelay(100);
ret = nand_status_op(chip, NULL);
if (ret)
return ret;
if (in_interrupt() || oops_in_progress)
panic_nand_wait(chip, timeo);
else {
timeo = jiffies + msecs_to_jiffies(timeo);
do {
if (chip->legacy.dev_ready) {
if (chip->legacy.dev_ready(chip))
break;
} else {
ret = nand_read_data_op(chip, &status,
sizeof(status), true);
if (ret)
return ret;
if (status & NAND_STATUS_READY)
break;
}
cond_resched();
} while (time_before(jiffies, timeo));
}
ret = nand_read_data_op(chip, &status, sizeof(status), true);
if (ret)
return ret;
/* This can happen if in case of timeout or buggy dev_ready */
WARN_ON(!(status & NAND_STATUS_READY));
return status;
}
void nand_legacy_set_defaults(struct nand_chip *chip)
{
unsigned int busw = chip->options & NAND_BUSWIDTH_16;
if (nand_has_exec_op(chip))
return;
/* check for proper chip_delay setup, set 20us if not */
if (!chip->legacy.chip_delay)
chip->legacy.chip_delay = 20;
/* check, if a user supplied command function given */
if (!chip->legacy.cmdfunc)
chip->legacy.cmdfunc = nand_command;
/* check, if a user supplied wait function given */
if (chip->legacy.waitfunc == NULL)
chip->legacy.waitfunc = nand_wait;
if (!chip->legacy.select_chip)
chip->legacy.select_chip = nand_select_chip;
/* If called twice, pointers that depend on busw may need to be reset */
if (!chip->legacy.read_byte || chip->legacy.read_byte == nand_read_byte)
chip->legacy.read_byte = busw ? nand_read_byte16 : nand_read_byte;
if (!chip->legacy.write_buf || chip->legacy.write_buf == nand_write_buf)
chip->legacy.write_buf = busw ? nand_write_buf16 : nand_write_buf;
if (!chip->legacy.write_byte || chip->legacy.write_byte == nand_write_byte)
chip->legacy.write_byte = busw ? nand_write_byte16 : nand_write_byte;
if (!chip->legacy.read_buf || chip->legacy.read_buf == nand_read_buf)
chip->legacy.read_buf = busw ? nand_read_buf16 : nand_read_buf;
}
void nand_legacy_adjust_cmdfunc(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
/* Do not replace user supplied command function! */
if (mtd->writesize > 512 && chip->legacy.cmdfunc == nand_command)
chip->legacy.cmdfunc = nand_command_lp;
}
int nand_legacy_check_hooks(struct nand_chip *chip)
{
/*
* ->legacy.cmdfunc() is legacy and will only be used if ->exec_op() is
* not populated.
*/
if (nand_has_exec_op(chip))
return 0;
/*
* Default functions assigned for ->legacy.cmdfunc() and
* ->legacy.select_chip() both expect ->legacy.cmd_ctrl() to be
* populated.
*/
if ((!chip->legacy.cmdfunc || !chip->legacy.select_chip) &&
!chip->legacy.cmd_ctrl) {
pr_err("->legacy.cmd_ctrl() should be provided\n");
return -EINVAL;
}
return 0;
}