esp-idf/components/spi_flash/flash_mmap.c

215 lines
7.4 KiB
C

// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
//
// 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 <stdlib.h>
#include <assert.h>
#include <string.h>
#include <stdio.h>
#include <freertos/FreeRTOS.h>
#include <freertos/task.h>
#include <freertos/semphr.h>
#include <rom/spi_flash.h>
#include <rom/cache.h>
#include <soc/soc.h>
#include <soc/dport_reg.h>
#include "sdkconfig.h"
#include "esp_ipc.h"
#include "esp_attr.h"
#include "esp_spi_flash.h"
#include "esp_log.h"
#include "cache_utils.h"
#ifndef NDEBUG
// Enable built-in checks in queue.h in debug builds
#define INVARIANTS
#endif
#include "rom/queue.h"
#define REGIONS_COUNT 4
#define PAGES_PER_REGION 64
#define FLASH_PAGE_SIZE 0x10000
#define INVALID_ENTRY_VAL 0x100
#define VADDR0_START_ADDR 0x3F400000
#define VADDR1_START_ADDR 0x40000000
#define VADDR1_FIRST_USABLE_ADDR 0x400D0000
#define PRO_IRAM0_FIRST_USABLE_PAGE ((VADDR1_FIRST_USABLE_ADDR - VADDR1_START_ADDR) / FLASH_PAGE_SIZE + 64)
typedef struct mmap_entry_{
uint32_t handle;
int page;
int count;
LIST_ENTRY(mmap_entry_) entries;
} mmap_entry_t;
static LIST_HEAD(mmap_entries_head, mmap_entry_) s_mmap_entries_head =
LIST_HEAD_INITIALIZER(s_mmap_entries_head);
static uint8_t s_mmap_page_refcnt[REGIONS_COUNT * PAGES_PER_REGION] = {0};
static uint32_t s_mmap_last_handle = 0;
static void IRAM_ATTR spi_flash_mmap_init()
{
for (int i = 0; i < REGIONS_COUNT * PAGES_PER_REGION; ++i) {
uint32_t entry_pro = DPORT_PRO_FLASH_MMU_TABLE[i];
uint32_t entry_app = DPORT_APP_FLASH_MMU_TABLE[i];
if (entry_pro != entry_app) {
// clean up entries used by boot loader
entry_pro = 0;
DPORT_PRO_FLASH_MMU_TABLE[i] = 0;
}
if ((entry_pro & 0x100) == 0 && (i == 0 || i == PRO_IRAM0_FIRST_USABLE_PAGE || entry_pro != 0)) {
s_mmap_page_refcnt[i] = 1;
}
}
}
esp_err_t IRAM_ATTR spi_flash_mmap(uint32_t src_addr, size_t size, spi_flash_mmap_memory_t memory,
const void** out_ptr, spi_flash_mmap_handle_t* out_handle)
{
esp_err_t ret;
mmap_entry_t* new_entry = (mmap_entry_t*) malloc(sizeof(mmap_entry_t));
if (new_entry == 0) {
return ESP_ERR_NO_MEM;
}
if (src_addr & 0xffff) {
return ESP_ERR_INVALID_ARG;
}
if (src_addr + size > g_rom_flashchip.chip_size) {
return ESP_ERR_INVALID_ARG;
}
spi_flash_disable_interrupts_caches_and_other_cpu();
if (s_mmap_page_refcnt[0] == 0) {
spi_flash_mmap_init();
}
// figure out the memory region where we should look for pages
int region_begin; // first page to check
int region_size; // number of pages to check
uint32_t region_addr; // base address of memory region
if (memory == SPI_FLASH_MMAP_DATA) {
// Vaddr0
region_begin = 0;
region_size = 64;
region_addr = VADDR0_START_ADDR;
} else {
// only part of VAddr1 is usable, so adjust for that
region_begin = VADDR1_FIRST_USABLE_ADDR;
region_size = 3 * 64 - region_begin;
region_addr = VADDR1_FIRST_USABLE_ADDR;
}
// region which should be mapped
int phys_page = src_addr / FLASH_PAGE_SIZE;
int page_count = (size + FLASH_PAGE_SIZE - 1) / FLASH_PAGE_SIZE;
// The following part searches for a range of MMU entries which can be used.
// Algorithm is essentially naïve strstr algorithm, except that unused MMU
// entries are treated as wildcards.
int start;
int end = region_begin + region_size - page_count;
for (start = region_begin; start < end; ++start) {
int page = phys_page;
int pos;
for (pos = start; pos < start + page_count; ++pos, ++page) {
int table_val = (int) DPORT_PRO_FLASH_MMU_TABLE[pos];
uint8_t refcnt = s_mmap_page_refcnt[pos];
if (refcnt != 0 && table_val != page) {
break;
}
}
// whole mapping range matched, bail out
if (pos - start == page_count) {
break;
}
}
// checked all the region(s) and haven't found anything?
if (start == end) {
*out_handle = 0;
*out_ptr = NULL;
ret = ESP_ERR_NO_MEM;
} else {
// set up mapping using pages [start, start + page_count)
uint32_t entry_val = (uint32_t) phys_page;
for (int i = start; i != start + page_count; ++i, ++entry_val) {
// sanity check: we won't reconfigure entries with non-zero reference count
assert(s_mmap_page_refcnt[i] == 0 ||
(DPORT_PRO_FLASH_MMU_TABLE[i] == entry_val &&
DPORT_APP_FLASH_MMU_TABLE[i] == entry_val));
if (s_mmap_page_refcnt[i] == 0) {
DPORT_PRO_FLASH_MMU_TABLE[i] = entry_val;
DPORT_APP_FLASH_MMU_TABLE[i] = entry_val;
}
++s_mmap_page_refcnt[i];
}
LIST_INSERT_HEAD(&s_mmap_entries_head, new_entry, entries);
new_entry->page = start;
new_entry->count = page_count;
new_entry->handle = ++s_mmap_last_handle;
*out_handle = new_entry->handle;
*out_ptr = (void*) (region_addr + start * FLASH_PAGE_SIZE);
ret = ESP_OK;
}
spi_flash_enable_interrupts_caches_and_other_cpu();
if (*out_ptr == NULL) {
free(new_entry);
}
return ret;
}
void IRAM_ATTR spi_flash_munmap(spi_flash_mmap_handle_t handle)
{
spi_flash_disable_interrupts_caches_and_other_cpu();
mmap_entry_t* it;
// look for handle in linked list
for (it = LIST_FIRST(&s_mmap_entries_head); it != NULL; it = LIST_NEXT(it, entries)) {
if (it->handle == handle) {
// for each page, decrement reference counter
// if reference count is zero, disable MMU table entry to
// facilitate debugging of use-after-free conditions
for (int i = it->page; i < it->page + it->count; ++i) {
assert(s_mmap_page_refcnt[i] > 0);
if (--s_mmap_page_refcnt[i] == 0) {
DPORT_PRO_FLASH_MMU_TABLE[i] = INVALID_ENTRY_VAL;
DPORT_APP_FLASH_MMU_TABLE[i] = INVALID_ENTRY_VAL;
}
}
LIST_REMOVE(it, entries);
break;
}
}
spi_flash_enable_interrupts_caches_and_other_cpu();
if (it == NULL) {
assert(0 && "invalid handle, or handle already unmapped");
}
free(it);
}
void spi_flash_mmap_dump()
{
if (s_mmap_page_refcnt[0] == 0) {
spi_flash_mmap_init();
}
mmap_entry_t* it;
for (it = LIST_FIRST(&s_mmap_entries_head); it != NULL; it = LIST_NEXT(it, entries)) {
printf("handle=%d page=%d count=%d\n", it->handle, it->page, it->count);
}
for (int i = 0; i < REGIONS_COUNT * PAGES_PER_REGION; ++i) {
if (s_mmap_page_refcnt[i] != 0) {
printf("page %d: refcnt=%d paddr=%d\n",
i, (int) s_mmap_page_refcnt[i], DPORT_PRO_FLASH_MMU_TABLE[i]);
}
}
}