diff --git a/flashchips.c b/flashchips.c
index 76e32b5..9fb3914 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -8299,13 +8299,13 @@
 
 	{
 		.vendor		= "GigaDevice",
-		.name		= "GD25Q256D/GD25Q256E",
+		.name		= "GD25Q256D/GD25B256D",
 		.bustype	= BUS_SPI,
 		.manufacture_id	= GIGADEVICE_ID,
 		.model_id	= GIGADEVICE_GD25Q256D,
 		.total_size	= 32768,
 		.page_size	= 256,
-		.feature_bits	= FEATURE_WRSR_WREN | FEATURE_OTP | FEATURE_4BA |
+		.feature_bits	= FEATURE_WRSR_EITHER | FEATURE_OTP | FEATURE_4BA |
 				  FEATURE_WRSR_EXT2 | FEATURE_WRSR2 | FEATURE_WRSR3 |
 				  FEATURE_QIO,
 		.tested		= TEST_OK_PREWB,
@@ -8339,14 +8339,14 @@
 				.block_erase = spi_block_erase_c7,
 			}
 		},
-		.printlock	= spi_prettyprint_status_register_bp3_srwd,
-		.unlock		= spi_disable_blockprotect,
+		.printlock	= spi_prettyprint_status_register_bp4_srwd,
+		.unlock		= spi_disable_blockprotect_bp4_srwd,
 		.write		= spi_chip_write_256,
 		.read		= spi_chip_read,
 		.voltage	= {2700, 3600},
 		.reg_bits	=
 		{
-			.qe	= {STATUS2, 1, RW},
+			.qe	= {STATUS2, 1, RW}, /* GD25B256D: Fixed QE=1 */
 			.srp    = {STATUS1, 7, RW},
 			.srl    = {STATUS2, 6, RW},
 			.bp     = {{STATUS1, 2, RW}, {STATUS1, 3, RW}, {STATUS1, 4, RW}, {STATUS1, 5, RW}},
@@ -8362,6 +8362,132 @@
 
 	{
 		.vendor		= "GigaDevice",
+		.name		= "GD25Q257D/GD25B257D",
+		.bustype	= BUS_SPI,
+		.manufacture_id	= GIGADEVICE_ID,
+		.model_id	= GIGADEVICE_GD25Q256D,
+		.total_size	= 32768,
+		.page_size	= 256,
+		.feature_bits	= FEATURE_WRSR_EITHER | FEATURE_WRSR_EXT2 | FEATURE_WRSR2 | FEATURE_WRSR3 |
+				  FEATURE_OTP | FEATURE_4BA | FEATURE_QIO,
+		.tested		= TEST_UNTESTED,
+		.probe		= probe_spi_rdid,
+		.probe_timing	= TIMING_ZERO,
+		.block_erasers	=
+		{
+			{
+				.eraseblocks = { {4 * 1024, 8192} },
+				.block_erase = spi_block_erase_21,
+			}, {
+				.eraseblocks = { {4 * 1024, 8192} },
+				.block_erase = spi_block_erase_20,
+			}, {
+				.eraseblocks = { {32 * 1024, 1024} },
+				.block_erase = spi_block_erase_5c,
+			}, {
+				.eraseblocks = { {32 * 1024, 1024} },
+				.block_erase = spi_block_erase_52,
+			}, {
+				.eraseblocks = { {64 * 1024, 512} },
+				.block_erase = spi_block_erase_dc,
+			}, {
+				.eraseblocks = { {64 * 1024, 512} },
+				.block_erase = spi_block_erase_d8,
+			}, {
+				.eraseblocks = { {32 * 1024 * 1024, 1} },
+				.block_erase = spi_block_erase_60,
+			}, {
+				.eraseblocks = { {32 * 1024 * 1024, 1} },
+				.block_erase = spi_block_erase_c7,
+			}
+		},
+		.printlock	= spi_prettyprint_status_register_bp4_srwd,
+		.unlock		= spi_disable_blockprotect_bp4_srwd,
+		.write		= spi_chip_write_256,
+		.read		= spi_chip_read,
+		.voltage	= {2700, 3600},
+		.reg_bits	=
+		{
+			.qe	= {STATUS2, 1, RW}, /* GD25B257D: Fixed QE=1 */
+			.srp	= {STATUS1, 7, RW},
+			.bp	= {{STATUS1, 2, RW}, {STATUS1, 3, RW}, {STATUS1, 4, RW}, {STATUS1, 5, RW}},
+			.tb	= {STATUS1, 6, RW},
+		},
+		.wp_write_cfg	= spi_wp_write_cfg,
+		.wp_read_cfg	= spi_wp_read_cfg,
+		.wp_get_ranges	= spi_wp_get_available_ranges,
+		.decode_range	= decode_range_spi25,
+		.prepare_access	= spi_prepare_io,
+		.finish_access	= spi_finish_io,
+	},
+
+	{
+		.vendor		= "GigaDevice",
+		.name		= "GD25Q256E/GD25B256E/GD25R256E",
+		.bustype	= BUS_SPI,
+		.manufacture_id	= GIGADEVICE_ID,
+		.model_id	= GIGADEVICE_GD25Q256D,
+		.total_size	= 32768,
+		.page_size	= 256,
+		/* Supports full QIO but has non-volatile DC bits. */
+		.feature_bits	= FEATURE_WRSR_EITHER | FEATURE_WRSR2 | FEATURE_WRSR3 |
+				  FEATURE_OTP | FEATURE_4BA | FEATURE_FAST_READ |
+				  FEATURE_FAST_READ_DOUT | FEATURE_FAST_READ_QOUT,
+		.tested		= TEST_UNTESTED,
+		.probe		= probe_spi_rdid,
+		.probe_timing	= TIMING_ZERO,
+		.block_erasers	=
+		{
+			{
+				.eraseblocks = { {4 * 1024, 8192} },
+				.block_erase = spi_block_erase_21,
+			}, {
+				.eraseblocks = { {4 * 1024, 8192} },
+				.block_erase = spi_block_erase_20,
+			}, {
+				.eraseblocks = { {32 * 1024, 1024} },
+				.block_erase = spi_block_erase_5c,
+			}, {
+				.eraseblocks = { {32 * 1024, 1024} },
+				.block_erase = spi_block_erase_52,
+			}, {
+				.eraseblocks = { {64 * 1024, 512} },
+				.block_erase = spi_block_erase_dc,
+			}, {
+				.eraseblocks = { {64 * 1024, 512} },
+				.block_erase = spi_block_erase_d8,
+			}, {
+				.eraseblocks = { {32 * 1024 * 1024, 1} },
+				.block_erase = spi_block_erase_60,
+			}, {
+				.eraseblocks = { {32 * 1024 * 1024, 1} },
+				.block_erase = spi_block_erase_c7,
+			}
+		},
+		.printlock	= spi_prettyprint_status_register_bp4_srwd,
+		.unlock		= spi_disable_blockprotect_bp4_srwd,
+		.write		= spi_chip_write_256,
+		.read		= spi_chip_read,
+		.voltage	= {2700, 3600},
+		.reg_bits	=
+		{
+			.qe	= {STATUS2, 1, RW}, /* GD25B/R: Fixed QE=1 */
+			.dc	= {{STATUS3, 0, RW}, {STATUS3, 1, RW}},
+			.srp	= {STATUS1, 7, RW},
+			.srl	= {STATUS2, 6, RW},
+			.bp	= {{STATUS1, 2, RW}, {STATUS1, 3, RW}, {STATUS1, 4, RW}, {STATUS1, 5, RW}},
+			.tb	= {STATUS1, 6, RW},
+		},
+		.wp_write_cfg	= spi_wp_write_cfg,
+		.wp_read_cfg	= spi_wp_read_cfg,
+		.wp_get_ranges	= spi_wp_get_available_ranges,
+		.decode_range	= decode_range_spi25,
+		.prepare_access	= spi_prepare_io,
+		.finish_access	= spi_finish_io,
+	},
+
+	{
+		.vendor		= "GigaDevice",
 		.name		= "GD25Q32(B)",
 		.bustype	= BUS_SPI,
 		.manufacture_id	= GIGADEVICE_ID,