Storage: add QSPIFReadPartitions example sketch

Former-commit-id: ae9a544

Author: pennam

libraries/Storage/examples/QSPIFReadPartitions/QSPIFReadPartitions.ino

@@ -0,0 +1,136 @@
+/*
+  Portenta C33 - QSPI Read partitions
+
+  The sketch reads the partition table of QSPI flash and prints the
+  results on the  serial monitor
+
+  This example code is in the public domain.
+*/
+
+#include <BlockDevice.h>
+
+struct __attribute__((packed)) mbrEntry {
+    uint8_t status;
+    uint8_t chsStart[3];
+    uint8_t type;
+    uint8_t chsStop[3];
+    uint32_t lbaOffset;
+    uint32_t lbaSize;
+};
+
+struct __attribute__((packed)) mbrTable {
+    mbrEntry entries[4];
+    uint8_t signature[2];
+};
+
+unsigned long allocatedSpace {};
+
+void setup()
+{
+    Serial.begin(9600);
+    for (const auto timeout = millis() + 2500; !Serial && millis() < timeout; delay(250))
+        ;
+
+    auto bd = BlockDevice::get_default_instance();
+    auto ret = bd->init();
+    if (ret) {
+        Serial.println("ERROR! Unable to read the Block Device.");
+        while (true)
+            ;
+    }
+
+    // Allocate smallest buffer necessary to write MBR
+    auto buffer_size = std::max<uint32_t>(bd->get_program_size(), sizeof(mbrTable));
+
+    // Prevent alignment issues
+    if (buffer_size % bd->get_program_size() != 0) {
+        buffer_size += bd->get_program_size() - (buffer_size % bd->get_program_size());
+    }
+
+    auto buffer = new uint8_t[buffer_size];
+
+    // Check for existing MBR
+    ret = bd->read(buffer, 512 - buffer_size, buffer_size);
+    if (ret) {
+        Serial.println("ERROR! Unable to read the Master Boot Record");
+
+        delete[] buffer;
+        while (true)
+            ;
+    }
+
+    auto table_start_offset = buffer_size - sizeof(mbrTable);
+    auto table = reinterpret_cast<mbrTable*>(&buffer[table_start_offset]);
+
+    Serial.println();
+    Serial.print("Looking for Partitions on the Flash Memory... ");
+
+    if (table->signature[0] != 0x55 || table->signature[1] != 0xAA) {
+        Serial.println("MBR Not Found");
+        Serial.println("Flash Memory doesn't have partitions.");
+    } else {
+
+        Serial.println("MBR Found");
+        Serial.print("Boot Signature: 0x");
+        Serial.print(table->signature[0], HEX);
+        Serial.println(table->signature[1], HEX);
+
+        Serial.println();
+        Serial.println("Printing Partitions Table and Info...");
+
+        auto part { 1u };
+        for (auto const& entry : table->entries) {
+            Serial.println("================================");
+            Serial.print("Partition: ");
+            Serial.println(part++);
+
+            Serial.print("Bootable: ");
+            Serial.println(entry.status == 0 ? "No" : "Yes");
+
+            Serial.print("Type: 0x");
+            if (entry.type < 0x10)
+                Serial.print(0);
+            Serial.println(entry.type, HEX);
+
+            if (entry.type == 0x00)
+                continue;
+
+            Serial.print("Size [KBytes]: ");
+            Serial.println((entry.lbaSize * 4096) >> 10);
+
+            allocatedSpace += entry.lbaSize * 4096;
+
+            Serial.print("Start [C/H/S]: ");
+            Serial.print(entry.chsStart[0]);
+            Serial.print("/");
+            Serial.print(entry.chsStart[1]);
+            Serial.print("/");
+            Serial.println(entry.chsStart[2]);
+
+            Serial.print("Stop [C/H/S]: ");
+            Serial.print(entry.chsStop[0]);
+            Serial.print("/");
+            Serial.print(entry.chsStop[1]);
+            Serial.print("/");
+            Serial.println(entry.chsStop[2]);
+
+            Serial.println();
+        }
+
+        Serial.println();
+        Serial.println("No more partitions are present.");
+    }
+
+    Serial.println();
+    Serial.print("Total Space [KBytes]:         ");
+    Serial.println(bd->size() >> 10);
+    Serial.print("Allocated Space [KBytes]:     ");
+    Serial.println(allocatedSpace >> 10);
+    Serial.print("Unallocated Space [KBytes]:   ");
+    Serial.println((bd->size() - allocatedSpace) >> 10);
+}
+
+void loop()
+{
+    delay(10000);
+}