/** * Copyright (c) 2020 Raspberry Pi (Trading) Ltd. * * SPDX-License-Identifier: BSD-3-Clause */ #include <stdio.h> #include "pico/stdlib.h" #include "pico/bootrom.h" #include "boot/picobin.h" int main() { stdio_init_all(); static uint8_t flash_buffer[0x1000] = {}; cflash_flags_t flags; flags.flags = (CFLASH_OP_VALUE_READ << CFLASH_OP_LSB) | (CFLASH_SECLEVEL_VALUE_SECURE << CFLASH_SECLEVEL_LSB); int ret; // Unpartitioned space only has bootloader permissions, so secure reads will fail printf("Attempt to read start of flash\n"); ret = rom_flash_op(flags, XIP_BASE, sizeof(flash_buffer), flash_buffer); if (ret == BOOTROM_ERROR_NOT_PERMITTED) { printf("Not permitted, as expected\n"); } else { printf("ERROR: "); if (ret) { printf("Flash OP failed with %d\n", ret); } else { printf("Flash OP succeeded, when shouldn't have been permitted"); } } // Add a runtime partition at start of flash with all permissions, to allow access to that region of flash printf("Adding partition with all permissions\n"); ret = rom_add_flash_runtime_partition(0, 0x1000, PICOBIN_PARTITION_PERMISSIONS_BITS); if (ret != 0) { printf("ERROR: Failed to add runtime partition\n"); } // Reads from that partition will now succeed printf("Attempt to read start of flash\n"); ret = rom_flash_op(flags, XIP_BASE, sizeof(flash_buffer), flash_buffer); if (ret == 0) { printf("Read successful - read first 2 words %08x %08x\n", ((uint32_t*)flash_buffer)[0], ((uint32_t*)flash_buffer)[1]); } else { printf("ERROR: Flash OP failed with %d\n", ret); } // But reads from unpartitioned space will still fail printf("Attempt to read later in flash\n"); ret = rom_flash_op(flags, XIP_BASE + 0x1000, sizeof(flash_buffer), flash_buffer); if (ret == BOOTROM_ERROR_NOT_PERMITTED) { printf("Not permitted, as expected\n"); } else { printf("ERROR: "); if (ret) { printf("Flash OP failed with %d\n", ret); } else { printf("Flash OP succeeded, when it shouldn't have been permitted - read first 2 words %08x %08x\n", ((uint32_t*)flash_buffer)[0], ((uint32_t*)flash_buffer)[1]); } } }

This firmware image was imported from the pico-examples repository. 


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