Flashrom support for Winbond W25Q256 (0x4019)

W25Q256.patch

Index: flashchips.c
===================================================================
--- flashchips.c	(revision 1846)
+++ flashchips.c	(working copy)
@@ -13137,7 +13137,40 @@
 		.read		= spi_chip_read,
 		.voltage	= {2700, 3600},
 	},
+	{
+		.vendor		= "Winbond",
+		.name		= "W25Q256.V",
+		.bustype	= BUS_SPI,
+		.manufacture_id	= WINBOND_NEX_ID,
+		.model_id	= WINBOND_NEX_W25Q256_V,
+		.total_size	= 32678,
+		.page_size	= 256,
+		/* supports SFDP */
+		/* OTP: 1024B total, 256B reserved; read 0x48; write 0x42, erase 0x44, read ID 0x4B */
+		.feature_bits	= FEATURE_WRSR_WREN | FEATURE_OTP,
+		.tested		= TEST_OK_PREW,
+		.probe		= probe_spi_rdid,
+		.probe_timing	= TIMING_ZERO,
+		.block_erasers	=
+		{
+			{
+				.eraseblocks = { {64 * 1024 - 180, 512} },
+				.block_erase = spi_block_erase_52,
+			}, {
+				.eraseblocks = { {32 * 1024 * 1024 - 92160, 1} },
+				.block_erase = spi_block_erase_60,
+			}, {
+				.eraseblocks = { {32 * 1024 * 1024 - 92160, 1} },
+				.block_erase = spi_block_erase_c7,
+			}
+		},

+		.printlock	= spi_prettyprint_status_register_plain, /* TODO: improve */
+		.unlock		= spi_disable_blockprotect,
+		.write		= spi_chip_write_256,
+		.read		= spi_chip_read,
+		.voltage	= {1700, 1950}, /* Fast read (0x0B) and multi I/O supported */
+	},
 	{
 		.vendor		= "Winbond",
 		.name		= "W25Q20.W",
Index: spi.c
===================================================================
--- spi.c	(revision 1846)
+++ spi.c	(working copy)
@@ -103,18 +103,18 @@
 int spi_chip_read(struct flashctx *flash, uint8_t *buf, unsigned int start,
 		  unsigned int len)
 {
-	unsigned int addrbase = 0;
+	unsigned long long addrbase = 0;

 	/* Check if the chip fits between lowest valid and highest possible
 	 * address. Highest possible address with the current SPI implementation
-	 * means 0xffffff, the highest unsigned 24bit number.
+	 * means 0xffffffff, the highest unsigned 24bit number.
 	 */
 	addrbase = spi_get_valid_read_addr(flash);
-	if (addrbase + flash->chip->total_size * 1024 > (1 << 24)) {
+	if (addrbase + flash->chip->total_size * 1024 > (1ULL << 32)) {
 		msg_perr("Flash chip size exceeds the allowed access window. ");
 		msg_perr("Read will probably fail.\n");
 		/* Try to get the best alignment subject to constraints. */
-		addrbase = (1 << 24) - flash->chip->total_size * 1024;
+		addrbase = (1ULL << 32) - flash->chip->total_size * 1024;
 	}
 	/* Check if alignment is native (at least the largest power of two which
 	 * is a factor of the mapped size of the chip).

spi.c fix is courtesy of https://gist.github.com/devicenull/8735650