blob: 240c66060174b9e62e8367b3dc88fe8451bcfa0c [file] [log] [blame]
/*
* Mailbox Daemon Flash Helpers
*
* Copyright 2016 IBM
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#define _GNU_SOURCE
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <limits.h>
#include <poll.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/timerfd.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#include <inttypes.h>
#include <mtd/mtd-abi.h>
#include "mbox.h"
#include "common.h"
#include "mboxd_flash.h"
int init_flash_dev(struct mbox_context *context)
{
char *filename = get_dev_mtd();
int fd, rc = 0;
if (!filename) {
MSG_ERR("Couldn't find the PNOR /dev/mtd partition\n");
return -1;
}
MSG_DBG("Opening %s\n", filename);
/* Open Flash Device */
fd = open(filename, O_RDWR);
if (fd < 0) {
MSG_ERR("Couldn't open %s with flags O_RDWR: %s\n",
filename, strerror(errno));
rc = -errno;
goto out;
}
context->fds[MTD_FD].fd = fd;
/* Read the Flash Info */
if (ioctl(fd, MEMGETINFO, &context->mtd_info) == -1) {
MSG_ERR("Couldn't get information about MTD: %s\n",
strerror(errno));
rc = -1;
goto out;
}
if (context->flash_size == 0) {
/*
* PNOR images for current OpenPOWER systems are at most 64MB
* despite the PNOR itself sometimes being as big as 128MB. To
* ensure the image read from the PNOR is exposed in the LPC
* address space at the location expected by the host firmware,
* it is required that the image size be used for
* context->flash_size, and not the size of the flash device.
*
* However, the test cases specify the flash size via special
* test APIs (controlling flash behaviour) which don't have
* access to the mbox context. Rather than requiring
* error-prone assignments in every test case, we instead rely
* on context->flash_size being set to the size reported by the
* MEMINFO ioctl().
*
* As this case should never be hit in production (i.e. outside
* the test environment), log an error. As a consequence, this
* error is expected in the test case output.
*/
MSG_ERR("Flash size MUST be supplied on the commandline. However, continuing by assuming flash is %u bytes\n",
context->mtd_info.size);
context->flash_size = context->mtd_info.size;
}
/* We know the erase size so we can allocate the flash_erased bytemap */
context->erase_size_shift = log_2(context->mtd_info.erasesize);
context->flash_bmap = calloc(context->flash_size >>
context->erase_size_shift,
sizeof(*context->flash_bmap));
MSG_DBG("Flash erase size: 0x%.8x\n", context->mtd_info.erasesize);
out:
free(filename);
return rc;
}
void free_flash_dev(struct mbox_context *context)
{
free(context->flash_bmap);
close(context->fds[MTD_FD].fd);
}
/* Flash Functions */
/*
* flash_is_erased() - Check if an offset into flash is erased
* @context: The mbox context pointer
* @offset: The flash offset to check (bytes)
*
* Return: true if erased otherwise false
*/
static inline bool flash_is_erased(struct mbox_context *context,
uint32_t offset)
{
return context->flash_bmap[offset >> context->erase_size_shift]
== FLASH_ERASED;
}
/*
* set_flash_bytemap() - Set the flash erased bytemap
* @context: The mbox context pointer
* @offset: The flash offset to set (bytes)
* @count: Number of bytes to set
* @val: Value to set the bytemap to
*
* The flash bytemap only tracks the erased status at the erase block level so
* this will update the erased state for an (or many) erase blocks
*
* Return: 0 if success otherwise negative error code
*/
int set_flash_bytemap(struct mbox_context *context, uint32_t offset,
uint32_t count, uint8_t val)
{
if ((offset + count) > context->flash_size) {
return -MBOX_R_PARAM_ERROR;
}
MSG_DBG("Set flash bytemap @ 0x%.8x for 0x%.8x to %s\n",
offset, count, val ? "ERASED" : "DIRTY");
memset(context->flash_bmap + (offset >> context->erase_size_shift),
val,
align_up(count, 1 << context->erase_size_shift) >>
context->erase_size_shift);
return 0;
}
/*
* erase_flash() - Erase the flash
* @context: The mbox context pointer
* @offset: The flash offset to erase (bytes)
* @size: The number of bytes to erase
*
* Return: 0 on success otherwise negative error code
*/
int erase_flash(struct mbox_context *context, uint32_t offset, uint32_t count)
{
const uint32_t erase_size = 1 << context->erase_size_shift;
struct erase_info_user erase_info = { 0 };
int rc;
MSG_DBG("Erase flash @ 0x%.8x for 0x%.8x\n", offset, count);
/*
* We have an erased_bytemap for the flash so we want to avoid erasing
* blocks which we already know to be erased. Look for runs of blocks
* which aren't erased and erase the entire run at once to avoid how
* often we have to call the erase ioctl. If the block is already
* erased then there's nothing we need to do.
*/
while (count) {
if (!flash_is_erased(context, offset)) { /* Need to erase */
if (!erase_info.length) { /* Start of not-erased run */
erase_info.start = offset;
}
erase_info.length += erase_size;
} else if (erase_info.length) { /* Already erased|end of run? */
/* Erase the previous run which just ended */
MSG_DBG("Erase flash @ 0x%.8x for 0x%.8x\n",
erase_info.start, erase_info.length);
rc = ioctl(context->fds[MTD_FD].fd, MEMERASE,
&erase_info);
if (rc < 0) {
MSG_ERR("Couldn't erase flash at 0x%.8x\n",
erase_info.start);
return -MBOX_R_SYSTEM_ERROR;
}
/* Mark ERASED where we just erased */
set_flash_bytemap(context, erase_info.start,
erase_info.length, FLASH_ERASED);
erase_info.start = 0;
erase_info.length = 0;
}
offset += erase_size;
count -= erase_size;
}
if (erase_info.length) {
MSG_DBG("Erase flash @ 0x%.8x for 0x%.8x\n",
erase_info.start, erase_info.length);
rc = ioctl(context->fds[MTD_FD].fd, MEMERASE, &erase_info);
if (rc < 0) {
MSG_ERR("Couldn't erase flash at 0x%.8x\n",
erase_info.start);
return -MBOX_R_SYSTEM_ERROR;
}
/* Mark ERASED where we just erased */
set_flash_bytemap(context, erase_info.start, erase_info.length,
FLASH_ERASED);
}
return 0;
}
/*
* write_flash() - Write the flash from a provided buffer
* @context: The mbox context pointer
* @offset: The flash offset to write to (bytes)
* @buf: The buffer to write from (must be of atleast size)
* @size: The number of bytes to write
*
* Return: 0 on success otherwise negative error code
*/
int write_flash(struct mbox_context *context, uint32_t offset, void *buf,
uint32_t count)
{
uint32_t buf_offset = 0;
int rc;
MSG_DBG("Write flash @ 0x%.8x for 0x%.8x from %p\n", offset, count, buf);
if (lseek(context->fds[MTD_FD].fd, offset, SEEK_SET) != offset) {
MSG_ERR("Couldn't seek flash at pos: %u %s\n", offset,
strerror(errno));
return -MBOX_R_SYSTEM_ERROR;
}
while (count) {
rc = write(context->fds[MTD_FD].fd, buf + buf_offset, count);
if (rc < 0) {
MSG_ERR("Couldn't write to flash, write lost: %s\n",
strerror(errno));
return -MBOX_R_WRITE_ERROR;
}
/* Mark *NOT* erased where we just wrote */
set_flash_bytemap(context, offset + buf_offset, rc,
FLASH_DIRTY);
count -= rc;
buf_offset += rc;
}
return 0;
}