diff --git a/source/drivers/spi_flash.c b/source/drivers/spi_flash.c
index 64a20dd..36a9e7b 100644
--- a/source/drivers/spi_flash.c
+++ b/source/drivers/spi_flash.c
@@ -120,6 +120,59 @@ err_disable_write:
 	return 0;
 }
 
+static char *size_to_str(size_t size)
+{
+	char *s;
+	int ret;
+
+	if (size == 0) {
+		ret = asprintf(&s, "0");
+#if defined(TIB)
+	} else if (size % TIB == 0) {
+		ret = asprintf(&s, "%u TiB", size / TIB);
+#endif
+	} else if (size % GIB == 0) {
+		ret = asprintf(&s, "%u GiB", size / GIB);
+	} else if (size % MIB == 0) {
+		ret = asprintf(&s, "%u MiB", size / MIB);
+	} else if (size % KIB == 0) {
+		ret = asprintf(&s, "%u KiB", size / KIB);
+	} else {
+		ret = asprintf(&s, "%u B", size);
+	}
+
+	if (ret < 0)
+		return NULL;
+
+	return s;
+}
+
+static int flash_detect(struct flash_dev *dev)
+{
+	char cmd[1] = { SPI_FLASH_JEDEC_ID };
+	uint8_t data[4];
+	struct spi_dev *spi_dev = dev->priv;
+	char *s;
+	size_t size;
+
+	spi_set_cs_level(spi_dev, 0);
+	spi_tx_rx(spi_dev, data, cmd, sizeof cmd);
+	spi_tx_rx(spi_dev, data, NULL, sizeof data);
+	spi_set_cs_level(spi_dev, 1);
+
+	printf("JEDEC ID: %02x%02x%02x%02x\n",
+		data[0], data[1], data[2], data[3]);
+
+	size = SPI_FLASH_SIZE(data[2]);
+	s = size_to_str(size);
+
+	printf("Capacity: %u blocks (%s)\n",
+		size / (4 * KIB), s);
+	free(s);
+
+	return 0;
+}
+
 struct flash_dev *flash_probe(void)
 {
 	struct flash_dev *dev;
@@ -132,6 +185,8 @@ struct flash_dev *flash_probe(void)
 
 	dev->ops = &spi_flash_ops;
 
+	flash_detect(dev);
+
 	return dev;
 
 err_free_dev: