Issue #18: Check error memory entries at safety ram init

stm-firmware/safety/safety-memory.c

@@ -239,6 +239,35 @@ int safety_memory_set_boot_status(const struct safety_memory_boot_status *status
 	return 0;
 }
 
+static int safety_memory_check_error_entries()
+{
+	struct safety_memory_header header;
+	uint32_t addr;
+	uint32_t data;
+	int ret = 0;
+	int res;
+
+	if (safety_memory_get_header(&header) != SAFETY_MEMORY_INIT_VALID_MEMORY) {
+		return -2000;
+	}
+
+	for (addr = header.err_memory_offset; addr < header.err_memory_end; addr++) {
+		res = backup_ram_get_data(addr, &data, 1UL);
+		if (res)
+			return -100;
+
+		/* Valid flag entry */
+		if ((data & 0xFF) == 0x51)
+			continue;
+		if (data == SAFETY_MEMORY_NOP_ENTRY)
+			continue;
+
+		ret--;
+	}
+
+	return ret;
+}
+
 int safety_memory_get_error_entry_count(uint32_t *count);
 
 int safety_memory_check(void)
@@ -246,6 +275,10 @@ int safety_memory_check(void)
 	int res;
 
 	res = safety_memory_check_crc();
+	if (!res) {
+		res |= safety_memory_check_error_entries();
+	}
+
 	return -!!res;
 }