Merge branch 'bugfix/existing_mmap_region_offset_v5.3' into 'release/v5.3'

fix(esp_mm): for existing mmap region, consider new offset for virtual addr (v5.3)

See merge request espressif/esp-idf!32112

Author: AdityaHPatwardhan

components/esp_mm/esp_mmu_map.c

@@ -509,7 +509,15 @@ esp_err_t esp_mmu_map(esp_paddr_t paddr_start, size_t size, mmu_target_t target,
 
     if (is_enclosed) {
         ESP_LOGW(TAG, "paddr block is mapped already, vaddr_start: %p, size: 0x%x", (void *)mem_block->vaddr_start, mem_block->size);
-        *out_ptr = (void *)mem_block->vaddr_start;
+        /*
+         * This condition is triggered when `s_is_enclosed` is true and hence
+         * we are sure that `paddr_start` >= `mem_block->paddr_start`.
+         *
+         * Add the offset of new physical address while returning the virtual
+         * address.
+         */
+        const uint32_t new_paddr_offset = paddr_start - mem_block->paddr_start;
+        *out_ptr = (void *)mem_block->vaddr_start + new_paddr_offset;
         return ESP_ERR_INVALID_STATE;
     }
 

components/esp_mm/include/esp_mmu_map.h

@@ -75,7 +75,7 @@ typedef uint32_t esp_paddr_t;
  *        - ESP_ERR_NOT_SUPPORTED: Only on ESP32, PSRAM is not a supported physical memory target
  *        - ESP_ERR_NOT_FOUND:     No enough size free block to use
  *        - ESP_ERR_NO_MEM:        Out of memory, this API will allocate some heap memory for internal usage
- *        - ESP_ERR_INVALID_STATE: Paddr is mapped already, this API will return corresponding vaddr_start of the previously mapped block.
+ *        - ESP_ERR_INVALID_STATE: Paddr is mapped already, this API will return corresponding `vaddr_start + new_block_offset` as per the previously mapped block.
  *                                 Only to-be-mapped paddr block is totally enclosed by a previously mapped block will lead to this error. (Identical scenario will behave similarly)
  *                                 new_block_start               new_block_end
  *                                              |-------- New Block --------|

components/spi_flash/test_apps/flash_mmap/main/test_flash_mmap.c

@@ -101,6 +101,33 @@ static void setup_mmap_tests(void)
     }
 }
 
+TEST_CASE("Can get correct data in existing mapped region", "[spi_flash][mmap]")
+{
+    setup_mmap_tests();
+
+    printf("Mapping %"PRIx32" (+%"PRIx32")\n", start, end - start);
+    const void *ptr1;
+    TEST_ESP_OK( spi_flash_mmap(start, end - start, SPI_FLASH_MMAP_DATA, &ptr1, &handle1) );
+    printf("mmap_res: handle=%"PRIx32" ptr=%p\n", (uint32_t)handle1, ptr1);
+
+    /* Remap in the previously mapped region itself */
+    uint32_t new_start = start + CONFIG_MMU_PAGE_SIZE;
+    printf("Mapping %"PRIx32" (+%"PRIx32")\n", new_start, end - new_start);
+    const void *ptr2;
+    TEST_ESP_OK( spi_flash_mmap(new_start, end - new_start, SPI_FLASH_MMAP_DATA, &ptr2, &handle2) );
+    printf("mmap_res: handle=%"PRIx32" ptr=%p\n", (uint32_t)handle2, ptr2);
+
+    const void *src1 = (void *) ((uint32_t) ptr1 + CONFIG_MMU_PAGE_SIZE);
+    const void *src2 = ptr2;
+    /* Memory contents should be identical - as the region is same */
+    TEST_ASSERT_EQUAL(0, memcmp(src1, src2, end - new_start));
+
+    spi_flash_munmap(handle1);
+    handle1 = 0;
+    spi_flash_munmap(handle2);
+    handle2 = 0;
+    TEST_ASSERT_EQUAL_PTR(NULL, spi_flash_phys2cache(start, SPI_FLASH_MMAP_DATA));
+}
 
 TEST_CASE("Can mmap into data address space", "[spi_flash][mmap]")
 {