diff options
Diffstat (limited to 'roms/skiboot/libflash/blocklevel.c')
-rw-r--r-- | roms/skiboot/libflash/blocklevel.c | 741 |
1 files changed, 741 insertions, 0 deletions
diff --git a/roms/skiboot/libflash/blocklevel.c b/roms/skiboot/libflash/blocklevel.c new file mode 100644 index 000000000..f11f337f4 --- /dev/null +++ b/roms/skiboot/libflash/blocklevel.c @@ -0,0 +1,741 @@ +// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later +/* Copyright 2013-2018 IBM Corp. */ + +#include <stdlib.h> +#include <unistd.h> +#include <stdio.h> +#include <stdbool.h> +#include <errno.h> +#include <string.h> +#include <inttypes.h> + +#include <libflash/libflash.h> +#include <libflash/errors.h> + +#include "blocklevel.h" +#include "ecc.h" + +#define PROT_REALLOC_NUM 25 + +/* This function returns tristate values. + * 1 - The region is ECC protected + * 0 - The region is not ECC protected + * -1 - Partially protected + */ +static int ecc_protected(struct blocklevel_device *bl, uint64_t pos, uint64_t len, uint64_t *start) +{ + int i; + + /* Length of 0 is nonsensical so add 1 */ + if (len == 0) + len = 1; + + for (i = 0; i < bl->ecc_prot.n_prot; i++) { + /* Fits entirely within the range */ + if (bl->ecc_prot.prot[i].start <= pos && + bl->ecc_prot.prot[i].start + bl->ecc_prot.prot[i].len >= pos + len) { + if (start) + *start = bl->ecc_prot.prot[i].start; + return 1; + } + + /* + * Even if ranges are merged we can't currently guarantee two + * contiguous regions are sanely ECC protected so a partial fit + * is no good. + */ + if ((bl->ecc_prot.prot[i].start >= pos && bl->ecc_prot.prot[i].start < pos + len) || + (bl->ecc_prot.prot[i].start <= pos && + bl->ecc_prot.prot[i].start + bl->ecc_prot.prot[i].len > pos)) { + if (start) + *start = bl->ecc_prot.prot[i].start; + return -1; + } + } + return 0; +} + +static uint64_t with_ecc_pos(uint64_t ecc_start, uint64_t pos) +{ + return pos + ((pos - ecc_start) / (BYTES_PER_ECC)); +} + +static int reacquire(struct blocklevel_device *bl) +{ + if (!bl->keep_alive && bl->reacquire) + return bl->reacquire(bl); + return 0; +} + +static int release(struct blocklevel_device *bl) +{ + int rc = 0; + if (!bl->keep_alive && bl->release) { + /* This is the error return path a lot, preserve errno */ + int err = errno; + rc = bl->release(bl); + errno = err; + } + return rc; +} + +int blocklevel_raw_read(struct blocklevel_device *bl, uint64_t pos, void *buf, uint64_t len) +{ + int rc; + + FL_DBG("%s: 0x%" PRIx64 "\t%p\t0x%" PRIx64 "\n", __func__, pos, buf, len); + if (!bl || !bl->read || !buf) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + rc = reacquire(bl); + if (rc) + return rc; + + rc = bl->read(bl, pos, buf, len); + + release(bl); + + return rc; +} + +int blocklevel_read(struct blocklevel_device *bl, uint64_t pos, void *buf, uint64_t len) +{ + int rc, ecc_protection; + struct ecc64 *buffer; + uint64_t ecc_pos, ecc_start, ecc_diff, ecc_len; + + FL_DBG("%s: 0x%" PRIx64 "\t%p\t0x%" PRIx64 "\n", __func__, pos, buf, len); + if (!bl || !buf) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + ecc_protection = ecc_protected(bl, pos, len, &ecc_start); + + FL_DBG("%s: 0x%" PRIx64 " for 0x%" PRIx64 " ecc=%s\n", + __func__, pos, len, ecc_protection ? + (ecc_protection == -1 ? "partial" : "yes") : "no"); + + if (!ecc_protection) + return blocklevel_raw_read(bl, pos, buf, len); + + /* + * The region we're reading to has both ecc protection and not. + * Perhaps one day in the future blocklevel can cope with this. + */ + if (ecc_protection == -1) { + FL_ERR("%s: Can't cope with partial ecc\n", __func__); + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + pos = with_ecc_pos(ecc_start, pos); + + ecc_pos = ecc_buffer_align(ecc_start, pos); + ecc_diff = pos - ecc_pos; + ecc_len = ecc_buffer_size(len + ecc_diff); + + FL_DBG("%s: adjusted_pos: 0x%" PRIx64 ", ecc_pos: 0x%" PRIx64 + ", ecc_diff: 0x%" PRIx64 ", ecc_len: 0x%" PRIx64 "\n", + __func__, pos, ecc_pos, ecc_diff, ecc_len); + buffer = malloc(ecc_len); + if (!buffer) { + errno = ENOMEM; + rc = FLASH_ERR_MALLOC_FAILED; + goto out; + } + + rc = blocklevel_raw_read(bl, ecc_pos, buffer, ecc_len); + if (rc) + goto out; + + /* + * Could optimise and simply call memcpy_from_ecc() if ecc_diff + * == 0 but _unaligned checks and bascially does that for us + */ + if (memcpy_from_ecc_unaligned(buf, buffer, len, ecc_diff)) { + errno = EBADF; + rc = FLASH_ERR_ECC_INVALID; + } + +out: + free(buffer); + return rc; +} + +int blocklevel_raw_write(struct blocklevel_device *bl, uint64_t pos, + const void *buf, uint64_t len) +{ + int rc; + + FL_DBG("%s: 0x%" PRIx64 "\t%p\t0x%" PRIx64 "\n", __func__, pos, buf, len); + if (!bl || !bl->write || !buf) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + rc = reacquire(bl); + if (rc) + return rc; + + rc = bl->write(bl, pos, buf, len); + + release(bl); + + return rc; +} + +int blocklevel_write(struct blocklevel_device *bl, uint64_t pos, const void *buf, + uint64_t len) +{ + int rc, ecc_protection; + struct ecc64 *buffer; + uint64_t ecc_len; + uint64_t ecc_start, ecc_pos, ecc_diff; + + FL_DBG("%s: 0x%" PRIx64 "\t%p\t0x%" PRIx64 "\n", __func__, pos, buf, len); + if (!bl || !buf) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + ecc_protection = ecc_protected(bl, pos, len, &ecc_start); + + FL_DBG("%s: 0x%" PRIx64 " for 0x%" PRIx64 " ecc=%s\n", + __func__, pos, len, ecc_protection ? + (ecc_protection == -1 ? "partial" : "yes") : "no"); + + if (!ecc_protection) + return blocklevel_raw_write(bl, pos, buf, len); + + /* + * The region we're writing to has both ecc protection and not. + * Perhaps one day in the future blocklevel can cope with this. + */ + if (ecc_protection == -1) { + FL_ERR("%s: Can't cope with partial ecc\n", __func__); + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + pos = with_ecc_pos(ecc_start, pos); + + ecc_pos = ecc_buffer_align(ecc_start, pos); + ecc_diff = pos - ecc_pos; + ecc_len = ecc_buffer_size(len + ecc_diff); + + FL_DBG("%s: adjusted_pos: 0x%" PRIx64 ", ecc_pos: 0x%" PRIx64 + ", ecc_diff: 0x%" PRIx64 ", ecc_len: 0x%" PRIx64 "\n", + __func__, pos, ecc_pos, ecc_diff, ecc_len); + + buffer = malloc(ecc_len); + if (!buffer) { + errno = ENOMEM; + rc = FLASH_ERR_MALLOC_FAILED; + goto out; + } + + if (ecc_diff) { + uint64_t start_chunk = ecc_diff; + uint64_t end_chunk = BYTES_PER_ECC - ecc_diff; + uint64_t end_len = ecc_len - end_chunk; + + /* + * Read the start bytes that memcpy_to_ecc_unaligned() will need + * to calculate the first ecc byte + */ + rc = blocklevel_raw_read(bl, ecc_pos, buffer, start_chunk); + if (rc) { + errno = EBADF; + rc = FLASH_ERR_ECC_INVALID; + goto out; + } + + /* + * Read the end bytes that memcpy_to_ecc_unaligned() will need + * to calculate the last ecc byte + */ + rc = blocklevel_raw_read(bl, ecc_pos + end_len, ((char *)buffer) + end_len, + end_chunk); + if (rc) { + errno = EBADF; + rc = FLASH_ERR_ECC_INVALID; + goto out; + } + + if (memcpy_to_ecc_unaligned(buffer, buf, len, ecc_diff)) { + errno = EBADF; + rc = FLASH_ERR_ECC_INVALID; + goto out; + } + } else { + if (memcpy_to_ecc(buffer, buf, len)) { + errno = EBADF; + rc = FLASH_ERR_ECC_INVALID; + goto out; + } + } + rc = blocklevel_raw_write(bl, pos, buffer, ecc_len); + +out: + free(buffer); + return rc; +} + +int blocklevel_erase(struct blocklevel_device *bl, uint64_t pos, uint64_t len) +{ + int rc; + if (!bl || !bl->erase) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + FL_DBG("%s: 0x%" PRIx64 "\t0x%" PRIx64 "\n", __func__, pos, len); + + /* Programmer may be making a horrible mistake without knowing it */ + if (pos & bl->erase_mask) { + FL_ERR("blocklevel_erase: pos (0x%"PRIx64") is not erase block (0x%08x) aligned\n", + pos, bl->erase_mask + 1); + return FLASH_ERR_ERASE_BOUNDARY; + } + + if (len & bl->erase_mask) { + FL_ERR("blocklevel_erase: len (0x%"PRIx64") is not erase block (0x%08x) aligned\n", + len, bl->erase_mask + 1); + return FLASH_ERR_ERASE_BOUNDARY; + } + + rc = reacquire(bl); + if (rc) + return rc; + + rc = bl->erase(bl, pos, len); + + release(bl); + + return rc; +} + +int blocklevel_get_info(struct blocklevel_device *bl, const char **name, uint64_t *total_size, + uint32_t *erase_granule) +{ + int rc; + + if (!bl || !bl->get_info) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + rc = reacquire(bl); + if (rc) + return rc; + + rc = bl->get_info(bl, name, total_size, erase_granule); + + /* Check the validity of what we are being told */ + if (erase_granule && *erase_granule != bl->erase_mask + 1) + FL_ERR("blocklevel_get_info: WARNING: erase_granule (0x%08x) and erase_mask" + " (0x%08x) don't match\n", *erase_granule, bl->erase_mask + 1); + + release(bl); + + return rc; +} + +/* + * Compare flash and memory to determine if: + * a) Erase must happen before write + * b) Flash and memory are identical + * c) Flash can simply be written to + * + * returns -1 for a + * returns 0 for b + * returns 1 for c + */ +static int blocklevel_flashcmp(const void *flash_buf, const void *mem_buf, uint64_t len) +{ + uint64_t i; + int same = true; + const uint8_t *f_buf, *m_buf; + + f_buf = flash_buf; + m_buf = mem_buf; + + for (i = 0; i < len; i++) { + if (m_buf[i] & ~f_buf[i]) + return -1; + if (same && (m_buf[i] != f_buf[i])) + same = false; + } + + return same ? 0 : 1; +} + +int blocklevel_smart_erase(struct blocklevel_device *bl, uint64_t pos, uint64_t len) +{ + uint64_t block_size; + void *erase_buf; + int rc; + + if (!bl) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + FL_DBG("%s: 0x%" PRIx64 "\t0x%" PRIx64 "\n", __func__, pos, len); + + /* Nothing smart needs to be done, pos and len are aligned */ + if ((pos & bl->erase_mask) == 0 && (len & bl->erase_mask) == 0) { + FL_DBG("%s: Skipping smarts everything is aligned 0x%" PRIx64 " 0x%" PRIx64 + "to 0x%08x\n", __func__, pos, len, bl->erase_mask); + return blocklevel_erase(bl, pos, len); + } + block_size = bl->erase_mask + 1; + erase_buf = malloc(block_size); + if (!erase_buf) { + errno = ENOMEM; + return FLASH_ERR_MALLOC_FAILED; + } + + rc = reacquire(bl); + if (rc) { + free(erase_buf); + return rc; + } + + if (pos & bl->erase_mask) { + /* + * base_pos and base_len are the values in the first erase + * block that we need to preserve: the region up to pos. + */ + uint64_t base_pos = pos & ~(bl->erase_mask); + uint64_t base_len = pos - base_pos; + + FL_DBG("%s: preserving 0x%" PRIx64 "..0x%" PRIx64 "\n", + __func__, base_pos, base_pos + base_len); + + /* + * Read the entire block in case this is the ONLY block we're + * modifying, we may need the end chunk of it later + */ + rc = bl->read(bl, base_pos, erase_buf, block_size); + if (rc) + goto out; + + rc = bl->erase(bl, base_pos, block_size); + if (rc) + goto out; + + rc = bl->write(bl, base_pos, erase_buf, base_len); + if (rc) + goto out; + + /* + * The requested erase fits entirely into this erase block and + * so we need to write back the chunk at the end of the block + */ + if (base_pos + base_len + len < base_pos + block_size) { + rc = bl->write(bl, pos + len, erase_buf + base_len + len, + block_size - base_len - len); + FL_DBG("%s: Early exit, everything was in one erase block\n", + __func__); + goto out; + } + + pos += block_size - base_len; + len -= block_size - base_len; + } + + /* Now we should be aligned, best to double check */ + if (pos & bl->erase_mask) { + FL_DBG("%s:pos 0x%" PRIx64 " isn't erase_mask 0x%08x aligned\n", + __func__, pos, bl->erase_mask); + rc = FLASH_ERR_PARM_ERROR; + goto out; + } + + if (len & ~(bl->erase_mask)) { + rc = bl->erase(bl, pos, len & ~(bl->erase_mask)); + if (rc) + goto out; + + pos += len & ~(bl->erase_mask); + len -= len & ~(bl->erase_mask); + } + + /* Length should be less than a block now */ + if (len > block_size) { + FL_DBG("%s: len 0x%" PRIx64 " is still exceeds block_size 0x%" PRIx64 "\n", + __func__, len, block_size); + rc = FLASH_ERR_PARM_ERROR; + goto out; + } + + if (len & bl->erase_mask) { + /* + * top_pos is the first byte that must be preserved and + * top_len is the length from top_pos to the end of the erase + * block: the region that must be preserved + */ + uint64_t top_pos = pos + len; + uint64_t top_len = block_size - len; + + FL_DBG("%s: preserving 0x%" PRIx64 "..0x%" PRIx64 "\n", + __func__, top_pos, top_pos + top_len); + + rc = bl->read(bl, top_pos, erase_buf, top_len); + if (rc) + goto out; + + rc = bl->erase(bl, pos, block_size); + if (rc) + goto out; + + rc = bl->write(bl, top_pos, erase_buf, top_len); + if (rc) + goto out; + } + +out: + free(erase_buf); + release(bl); + return rc; +} + +int blocklevel_smart_write(struct blocklevel_device *bl, uint64_t pos, const void *buf, uint64_t len) +{ + void *ecc_buf = NULL; + uint64_t ecc_start; + int ecc_protection; + + void *erase_buf = NULL; + uint32_t erase_size; + + const void *write_buf; + uint64_t write_len; + uint64_t write_pos; + + int rc = 0; + + if (!buf || !bl) { + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + FL_DBG("%s: 0x%" PRIx64 "\t0x%" PRIx64 "\n", __func__, pos, len); + + if (!(bl->flags & WRITE_NEED_ERASE)) { + FL_DBG("%s: backend doesn't need erase\n", __func__); + return blocklevel_write(bl, pos, buf, len); + } + + rc = blocklevel_get_info(bl, NULL, NULL, &erase_size); + if (rc) + return rc; + + ecc_protection = ecc_protected(bl, pos, len, &ecc_start); + if (ecc_protection == -1) { + FL_ERR("%s: Can't cope with partial ecc\n", __func__); + errno = EINVAL; + return FLASH_ERR_PARM_ERROR; + } + + if (ecc_protection) { + uint64_t ecc_pos, ecc_align, ecc_diff, ecc_len; + + FL_DBG("%s: region has ECC\n", __func__); + + ecc_pos = with_ecc_pos(ecc_start, pos); + ecc_align = ecc_buffer_align(ecc_start, ecc_pos); + ecc_diff = ecc_pos - ecc_align; + ecc_len = ecc_buffer_size(len + ecc_diff); + + ecc_buf = malloc(ecc_len); + if (!ecc_buf) { + errno = ENOMEM; + return FLASH_ERR_MALLOC_FAILED; + } + + if (ecc_diff) { + rc = blocklevel_read(bl, ecc_align, ecc_buf, ecc_diff); + if (rc) { + errno = EBADF; + rc = FLASH_ERR_ECC_INVALID; + goto out; + } + } + + rc = memcpy_to_ecc_unaligned(ecc_buf, buf, len, ecc_diff); + if (rc) { + free(ecc_buf); + errno = EBADF; + return FLASH_ERR_ECC_INVALID; + } + + write_buf = ecc_buf; + write_len = ecc_len; + write_pos = ecc_pos; + } else { + write_buf = buf; + write_len = len; + write_pos = pos; + } + + erase_buf = malloc(erase_size); + if (!erase_buf) { + errno = ENOMEM; + rc = FLASH_ERR_MALLOC_FAILED; + goto out_free; + } + + rc = reacquire(bl); + if (rc) + goto out_free; + + while (write_len > 0) { + uint32_t erase_block = write_pos & ~(erase_size - 1); + uint32_t block_offset = write_pos & (erase_size - 1); + uint32_t chunk_size = erase_size > write_len ? + write_len : erase_size; + int cmp; + + /* Write crosses an erase boundary, shrink the write to the boundary */ + if (erase_size < block_offset + chunk_size) { + chunk_size = erase_size - block_offset; + } + + rc = bl->read(bl, erase_block, erase_buf, erase_size); + if (rc) + goto out; + + cmp = blocklevel_flashcmp(erase_buf + block_offset, write_buf, + chunk_size); + FL_DBG("%s: region 0x%08x..0x%08x ", __func__, + erase_block, erase_size); + if (cmp != 0) { + FL_DBG("needs "); + if (cmp == -1) { + FL_DBG("erase and "); + bl->erase(bl, erase_block, erase_size); + } + FL_DBG("write\n"); + memcpy(erase_buf + block_offset, write_buf, chunk_size); + rc = bl->write(bl, erase_block, erase_buf, erase_size); + if (rc) + goto out; + } else { + FL_DBG("clean\n"); + } + + write_len -= chunk_size; + write_pos += chunk_size; + write_buf += chunk_size; + } + +out: + release(bl); +out_free: + free(ecc_buf); + free(erase_buf); + return rc; +} + +static bool insert_bl_prot_range(struct blocklevel_range *ranges, struct bl_prot_range range) +{ + int i; + uint32_t pos, len; + struct bl_prot_range *prot = ranges->prot; + + pos = range.start; + len = range.len; + + if (len == 0) + return true; + + /* Check for overflow */ + if (pos + len < len) + return false; + + for (i = 0; i < ranges->n_prot && len > 0; i++) { + if (prot[i].start <= pos && prot[i].start + prot[i].len >= pos + len) { + len = 0; + break; /* Might as well, the next two conditions can't be true */ + } + + /* Can easily extend this down just by adjusting start */ + if (pos <= prot[i].start && pos + len >= prot[i].start) { + FL_DBG("%s: extending start down\n", __func__); + prot[i].len += prot[i].start - pos; + prot[i].start = pos; + pos += prot[i].len; + if (prot[i].len >= len) + len = 0; + else + len -= prot[i].len; + } + + /* + * Jump over this range but the new range might be so big that + * theres a chunk after + */ + if (pos >= prot[i].start && pos < prot[i].start + prot[i].len) { + FL_DBG("%s: fits within current range ", __func__); + if (prot[i].start + prot[i].len - pos > len) { + FL_DBG("but there is some extra at the end\n"); + len -= prot[i].start + prot[i].len - pos; + pos = prot[i].start + prot[i].len; + } else { + FL_DBG("\n"); + len = 0; + } + } + /* + * This condition will be true if the range is smaller than + * the current range, therefore it should go here! + */ + if (pos < prot[i].start && pos + len <= prot[i].start) + break; + } + + if (len) { + int insert_pos = i; + struct bl_prot_range *new_ranges = ranges->prot; + + FL_DBG("%s: adding 0x%08x..0x%08x\n", __func__, pos, pos + len); + + if (ranges->n_prot == ranges->total_prot) { + new_ranges = realloc(ranges->prot, + sizeof(range) * ((ranges->n_prot) + PROT_REALLOC_NUM)); + if (!new_ranges) + return false; + ranges->total_prot += PROT_REALLOC_NUM; + } + if (insert_pos != ranges->n_prot) + for (i = ranges->n_prot; i > insert_pos; i--) + memcpy(&new_ranges[i], &new_ranges[i - 1], sizeof(range)); + range.start = pos; + range.len = len; + memcpy(&new_ranges[insert_pos], &range, sizeof(range)); + ranges->prot = new_ranges; + ranges->n_prot++; + prot = new_ranges; + } + + return true; +} + +int blocklevel_ecc_protect(struct blocklevel_device *bl, uint32_t start, uint32_t len) +{ + /* + * Could implement this at hardware level by having an accessor to the + * backend in struct blocklevel_device and as a result do nothing at + * this level (although probably not for ecc!) + */ + struct bl_prot_range range = { .start = start, .len = len }; + + if (len < BYTES_PER_ECC) + return -1; + return !insert_bl_prot_range(&bl->ecc_prot, range); +} |