pebble/src/fw/drivers/flash/cd_flash_driver.c
2025-01-27 11:38:16 -08:00

100 lines
3.2 KiB
C

/*
* Copyright 2024 Google LLC
*
* 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.
*/
#include <inttypes.h>
#include "drivers/flash.h"
#include "drivers/flash/flash_impl.h"
#include "drivers/watchdog.h"
#include "flash_region/flash_region.h"
#include "kernel/util/delay.h"
#include "kernel/core_dump_private.h"
//! We have our own flash driver for coredump support because it must not use
//! any FreeRTOS constructs & we want to keep it as simple as possible. In
//! addition we want the flexibility to be able to reset the flash driver to
//! get it into a working state
void cd_flash_init(void) {
// Reset & (re)initialize the flash HW
flash_impl_init(true /* coredump_mode */);
// Protect the PRF region from writes
flash_impl_write_protect(
FLASH_REGION_SAFE_FIRMWARE_BEGIN,
(FLASH_REGION_SAFE_FIRMWARE_END - SECTOR_SIZE_BYTES));
}
void cd_flash_erase_region(uint32_t start_addr, uint32_t total_bytes) {
CD_ASSERTN(((start_addr & SUBSECTOR_ADDR_MASK) == start_addr) &&
((total_bytes & SUBSECTOR_ADDR_MASK) == total_bytes));
while (total_bytes > 0) {
watchdog_feed();
uint32_t erase_size = 0;
if (((start_addr & SECTOR_ADDR_MASK) == start_addr) &&
(total_bytes >= SECTOR_SIZE_BYTES)) {
erase_size = SECTOR_SIZE_BYTES;
flash_impl_erase_sector_begin(start_addr);
} else if ((start_addr & SUBSECTOR_ADDR_MASK) == start_addr &&
(total_bytes >= SUBSECTOR_SIZE_BYTES)) {
erase_size = SUBSECTOR_SIZE_BYTES;
flash_impl_erase_subsector_begin(start_addr);
} else {
// Unaligned start address or unaligned erase size
CD_ASSERTN(0);
}
status_t status;
while ((status = flash_impl_get_erase_status()) == E_BUSY) delay_us(100);
CD_ASSERTN(status == S_SUCCESS);
total_bytes -= erase_size;
start_addr += erase_size;
}
watchdog_feed();
}
uint32_t cd_flash_write_bytes(const void *buffer_ptr, uint32_t start_addr,
const uint32_t buffer_size) {
CD_ASSERTN(((start_addr + buffer_size) <= CORE_DUMP_FLASH_END) &&
(int)start_addr >= CORE_DUMP_FLASH_START);
const uint8_t *buffer = buffer_ptr;
uint32_t remaining = buffer_size;
while (remaining) {
int written = flash_impl_write_page_begin(buffer, start_addr, remaining);
CD_ASSERTN(PASSED(written));
status_t status;
while ((status = flash_impl_get_write_status()) == E_BUSY) {
delay_us(10);
}
CD_ASSERTN(PASSED(status));
buffer += written;
start_addr += written;
remaining -= written;
}
return buffer_size;
}
void cd_flash_read_bytes(void* buffer_ptr, uint32_t start_addr,
uint32_t buffer_size) {
flash_impl_read_sync(buffer_ptr, start_addr, buffer_size);
}