Add a sample to read the partition table

README.md

@@ -102,6 +102,7 @@ App|Description
 [xip_stream](flash/xip_stream) | Stream data using the XIP stream hardware, which allows data to be DMA'd in the background whilst executing code from flash.
 [ssi_dma](flash/ssi_dma) | DMA directly from the flash interface (continuous SCK clocking) for maximum bulk read performance.
 [runtime_flash_permissions](flash/runtime_flash_permissions) | Demonstrates adding partitions at runtime to change the flash permissions
+[partition_info](flash/partition_info) | Extract and enumerate partition information (address ranges, permissions, IDs, and names) from the partition table.
 
 ### FreeRTOS
 

flash/CMakeLists.txt

@@ -5,6 +5,7 @@ if (TARGET hardware_flash)
     add_subdirectory_exclude_platforms(ssi_dma "rp2350.*")
     add_subdirectory_exclude_platforms(xip_stream)
     add_subdirectory_exclude_platforms(runtime_flash_permissions rp2040)
+    add_subdirectory_exclude_platforms(partition_info rp2040)
 else()
     message("Skipping flash examples as hardware_flash is unavailable on this platform")
-endif()
+endif()

flash/partition_info/CMakeLists.txt

@@ -0,0 +1,15 @@
+add_executable(partition_info partition_info.c)
+
+target_link_libraries(partition_info PRIVATE
+        pico_stdlib
+        pico_bootrom
+        )
+
+# add a partition table
+pico_embed_pt_in_binary(partition_info ${CMAKE_CURRENT_LIST_DIR}/pt.json)
+
+# create map/bin/hex/uf2 file etc.
+pico_add_extra_outputs(partition_info)
+
+# add url via pico_set_program_url
+example_auto_set_url(partition_info)

flash/partition_info/partition_info.c

@@ -0,0 +1,161 @@
+/**
+ * Copyright (c) 2023 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"
+
+
+#define PART_LOC_FIRST(x) ( ((x) & PICOBIN_PARTITION_LOCATION_FIRST_SECTOR_BITS) >> PICOBIN_PARTITION_LOCATION_FIRST_SECTOR_LSB )
+#define PART_LOC_LAST(x)  ( ((x) & PICOBIN_PARTITION_LOCATION_LAST_SECTOR_BITS)  >> PICOBIN_PARTITION_LOCATION_LAST_SECTOR_LSB )
+
+#define PARTITION_LOCATION_AND_FLAGS_SIZE  2
+#define PARTITION_ID_SIZE                  2
+#define PARTITION_NAME_MAX                 127
+#define PARTITION_TABLE_FIXED_INFO_SIZE    (4 + PARTITION_TABLE_MAX_PARTITIONS * (PARTITION_LOCATION_AND_FLAGS_SIZE + PARTITION_ID_SIZE))
+
+/*
+ * Stores partition table information and data read status
+ */
+typedef struct {
+    uint32_t table[PARTITION_TABLE_FIXED_INFO_SIZE];
+    uint32_t fields;
+    int partition_count;
+    uint32_t unpartitioned_space_first_sector;
+    uint32_t unpartitioned_space_last_sector;
+    uint32_t flags_and_permissions;
+    int current_partition;
+    size_t idx;
+    int status;
+} pico_partition_table_t;
+
+/*
+ * Stores information on each partition
+ */
+typedef struct {
+    uint32_t first_sector;
+    uint32_t last_sector;
+    uint32_t flags_and_permissions;
+    uint64_t partition_id;
+    char name[PARTITION_NAME_MAX + 1];  // name length is indicated by 7 bits
+} pico_partition_t;
+
+
+/*
+ * Read the partition table information.
+ *
+ * See the RP2350 datasheet 5.1.2, 5.4.8.16 for flags and structures that can be specified.
+ */
+int pico_partitions_open(pico_partition_table_t *pt) {
+    // Reads a fixed size fields
+    int rc = rom_get_partition_table_info(pt->table, sizeof(pt->table),
+                                          (PT_INFO_PT_INFO |
+                                           PT_INFO_PARTITION_LOCATION_AND_FLAGS |
+                                           PT_INFO_PARTITION_ID));
+    if (rc < 0) {
+        pt->status = rc;
+        return rc;
+    }
+
+    size_t pos = 0;
+    pt->fields = pt->table[pos++];
+    pt->partition_count = pt->table[pos++] & 0x000000FF;
+    uint32_t location = pt->table[pos++];
+    pt->unpartitioned_space_first_sector = PART_LOC_FIRST(location);
+    pt->unpartitioned_space_last_sector = PART_LOC_LAST(location);
+    pt->flags_and_permissions = pt->table[pos++];
+    pt->current_partition = 0;
+    pt->idx = pos;
+    pt->status = 0;
+
+    return 0;
+}
+
+/*
+ * Extract each partition information
+ */
+bool pico_partitions_next(pico_partition_table_t *pt, pico_partition_t *p) {
+    if (pt->current_partition >= pt->partition_count) {
+        return false;
+    }
+
+    size_t idx = pt->idx;
+    uint32_t location = pt->table[idx++];
+    p->first_sector = PART_LOC_FIRST(location);
+    p->last_sector = PART_LOC_LAST(location);
+    p->flags_and_permissions = pt->table[idx++];
+
+    if (p->flags_and_permissions & PICOBIN_PARTITION_FLAGS_HAS_ID_BITS) {
+        uint32_t id_low  = pt->table[idx++];
+        uint32_t id_high = pt->table[idx++];
+        p->partition_id = ((uint64_t)id_high << 32) | id_low;
+    } else {
+        p->partition_id = 0;
+    }
+    pt->idx = idx;
+
+    if (p->flags_and_permissions & PICOBIN_PARTITION_FLAGS_HAS_NAME_BITS) {
+        // Read variable length fields
+        uint32_t name_buf[(PARTITION_NAME_MAX + 1) / sizeof(uint32_t)] = {0};
+        int rc = rom_get_partition_table_info(name_buf, sizeof(name_buf),
+                                              (pt->current_partition << 24 |
+                                               PT_INFO_SINGLE_PARTITION |
+                                               PT_INFO_PARTITION_NAME));
+        if (rc < 0) {
+            pt->status = rc;
+            return false;
+        }
+        uint32_t __attribute__((unused)) fields = name_buf[0];
+        uint8_t *name_buf_u8 = (uint8_t *)&name_buf[1];
+        uint8_t name_length = *name_buf_u8++;
+        memcpy(p->name, name_buf_u8, name_length);
+        p->name[name_length] = '\0';
+    } else {
+        p->name[0] = '\0';
+    }
+
+    pt->current_partition++;
+    return true;
+}
+
+int main() {
+    stdio_init_all();
+
+    pico_partition_table_t pt;
+    pico_partitions_open(&pt);
+    printf("un-partitioned_space: S(%s%s) NSBOOT(%s%s) NS(%s%s)\n",
+           (pt.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_S_R_BITS ? "r" : ""),
+           (pt.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_S_W_BITS ? "w" : ""),
+           (pt.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NSBOOT_R_BITS ? "r" : ""),
+           (pt.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NSBOOT_W_BITS ? "w" : ""),
+           (pt.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NS_R_BITS ? "r" : ""),
+           (pt.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NS_W_BITS ? "w" : ""));
+    printf("partitions:\n");
+    pico_partition_t p;
+    while (pico_partitions_next(&pt, &p)) {
+        printf("%3d:", pt.current_partition - 1);
+        printf("    %08x->%08x S(%s%s) NSBOOT(%s%s) NS(%s%s)",
+               p.first_sector * 4096, (p.last_sector + 1) * 4096,
+               (p.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_S_R_BITS ? "r" : ""),
+               (p.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_S_W_BITS ? "w" : ""),
+               (p.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NSBOOT_R_BITS ? "r" : ""),
+               (p.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NSBOOT_W_BITS ? "w" : ""),
+               (p.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NS_R_BITS ? "r" : ""),
+               (p.flags_and_permissions & PICOBIN_PARTITION_PERMISSION_NS_W_BITS ? "w" : ""));
+        if (p.flags_and_permissions & PICOBIN_PARTITION_FLAGS_HAS_ID_BITS) {
+            printf(", id=%016llx", p.partition_id);
+        }
+        if (p.flags_and_permissions & PICOBIN_PARTITION_FLAGS_HAS_NAME_BITS) {
+            printf(", \"%s\"", p.name);
+        }
+        printf("\n");
+    }
+    if (pt.status != 0) {
+        panic("rom_get_partition_table_info returned %d", pt.status);
+    }
+
+    return 0;
+}

flash/partition_info/pt.json

@@ -0,0 +1,47 @@
+{
+  "version": [1, 0],
+  "unpartitioned": {
+    "families": ["absolute"],
+    "permissions": {
+      "secure": "rw",
+      "nonsecure": "rw",
+      "bootloader": "rw"
+    }
+  },
+  "partitions": [
+    {
+      "name": "Firmware",
+      "id": 1,
+      "start": 0,
+      "size": "512K",
+      "families": ["rp2350-arm-ns", "rp2350-arm-s", "rp2350-riscv"],
+      "permissions": {
+        "secure": "rw",
+        "nonsecure": "rw",
+        "bootloader": "rw"
+      }
+    },
+    {
+      "name": "Data",
+      "id": 2,
+      "size": "512K",
+      "families": ["data"],
+      "permissions": {
+        "secure": "rw",
+        "nonsecure": "rw",
+        "bootloader": "rw"
+      }
+    },
+    {
+      "name": "Read only Data",
+      "id": 3,
+      "size": "512K",
+      "families": ["data"],
+      "permissions": {
+        "secure": "r",
+        "nonsecure": "r",
+        "bootloader": "r"
+      }
+    }
+  ]
+}