Add continuation ID support to jedec.c

The continuation ID code does not go further than checking for IDs of
the type 0x7fXX, but does this for vendor and product ID. The current
published JEDEC spec has a list where the largest vendor ID is 7 bytes
long, but all leading bytes are 0x7f. The list will grow in the future,
and using a 64bit variable will not be enough anymore.
Besides that, it seems that the location of the ID byte after the first
continuation ID byte is very vendor specific, so we may have to revisit
that code some time in the future.

(Suggestion for a new encoding:
Use a two-byte data type for the ID, the lower byte contains the only
non-0x7f byte, the upper byte contains the number of 0x7f bytes used as
prefix, which is the bank number minus 1 the vendor ID appears in.)

Add support for EON EN29F002AT.

Corresponding to flashrom svn r171 and coreboot v2 svn r3030.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Corey Osgood <corey.osgood@gmail.com>

4 files changed, 126 insertions, 5 deletions

diff --git a/en29f002a.c b/en29f002a.c
new file mode 100644
index 0000000..e2b4f9b
--- /dev/null
+++ b/en29f002a.c
@@ -0,0 +1,85 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2007 Carl-Daniel Hailfinger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+/*
+   EN29F512 has 1C,21
+   EN29F010 has 1C,20
+   EN29F040A has 1C,04
+   EN29LV010 has 1C,6E and uses short F0 reset sequence
+   EN29LV040(A) has 1C,4F and uses short F0 reset sequence
+ */
+int probe_en29f512(struct flashchip *flash)
+{
+	volatile uint8_t *bios = flash->virtual_memory;
+	uint8_t id1, id2;
+
+	*(volatile uint8_t *)(bios + 0x555) = 0xAA;
+	*(volatile uint8_t *)(bios + 0x2AA) = 0x55;
+	*(volatile uint8_t *)(bios + 0x555) = 0x90;
+
+	myusec_delay(10);
+
+	id1 = *(volatile uint8_t *)(bios + 0x100);
+	id2 = *(volatile uint8_t *)(bios + 0x101);
+
+	/* exit by writing F0 anywhere? or the code below */
+	*(volatile uint8_t *)(bios + 0x555) = 0xAA;
+	*(volatile uint8_t *)(bios + 0x2AA) = 0x55;
+	*(volatile uint8_t *)(bios + 0x555) = 0xF0;
+
+	printf_debug("%s: id1 0x%x, id2 0x%x\n", __FUNCTION__, id1, id2);
+
+	if (id1 == flash->manufacture_id && id2 == flash->model_id)
+		return 1;
+
+	return 0;
+}
+
+/*
+   EN29F002AT has 1C,92
+   EN29F002AB has 1C,97
+ */
+int probe_en29f002a(struct flashchip *flash)
+{
+	volatile uint8_t *bios = flash->virtual_memory;
+	uint8_t id1, id2;
+
+	*(volatile uint8_t *)(bios + 0x555) = 0xAA;
+	*(volatile uint8_t *)(bios + 0xAAA) = 0x55;
+	*(volatile uint8_t *)(bios + 0x555) = 0x90;
+
+	myusec_delay(10);
+
+	id1 = *(volatile uint8_t *)(bios + 0x100);
+	id2 = *(volatile uint8_t *)(bios + 0x101);
+
+	/* exit by writing F0 anywhere? or the code below */
+	*(volatile uint8_t *)(bios + 0x555) = 0xAA;
+	*(volatile uint8_t *)(bios + 0xAAA) = 0x55;
+	*(volatile uint8_t *)(bios + 0x555) = 0xF0;
+
+	printf_debug("%s: id1 0x%x, id2 0x%x\n", __FUNCTION__, id1, id2);
+
+	if (id1 == flash->manufacture_id && id2 == flash->model_id)
+		return 1;
+
+	return 0;
+}
+
diff --git a/flash.h b/flash.h
index d8a86dd..d7c6597 100644
--- a/flash.h
+++ b/flash.h
@@ -32,8 +32,12 @@
 
 struct flashchip {
 	const char *name;
-	int manufacture_id;
-	int model_id;
+	/* With 32bit manufacture_id and model_id we can cover IDs up to
+	 * (including) the 4th bank of JEDEC JEP106W Standard Manufacturer's
+	 * Identification code.
+	 */
+	uint32_t manufacture_id;
+	uint32_t model_id;
 
 	int total_size;
 	int page_size;
@@ -85,8 +89,14 @@ extern struct flashchip flashchips[];
 /*
  * EN25 chips are SPI, first byte of device ID is memory type,
  * second byte of device ID is log(bitsize)-9.
+ * Vendor and device ID of EN29 series are both prefixed with 0x7F, which
+ * is the continuation code for IDs in bank 2.
+ * Vendor ID of EN25 series is NOT prefixed with 0x7F, this results in
+ * a collision with Mitsubishi. Mitsubishi once manufactured flash chips.
+ * Let's hope they are not manufacturing SPI flash chips as well.
  */
-#define EON_ID			0x1C	/* EON Silicon Devices */
+#define EON_ID			0x7F1C	/* EON Silicon Devices */
+#define EON_ID_NOPREFIX		0x1C	/* EON, missing 0x7F prefix */
 #define EN_25B05		0x2010	/* 2^19 kbit or 2^16 kByte */
 #define EN_25B10		0x2011
 #define EN_25B20		0x2012
@@ -94,6 +104,13 @@ extern struct flashchip flashchips[];
 #define EN_25B80		0x2014
 #define EN_25B16		0x2015
 #define EN_25B32		0x2016
+#define EN_29F512		0x7F21
+#define EN_29F010		0x7F20
+#define EN_29F040A		0x7F04
+#define EN_29LV010		0x7F6E
+#define EN_29LV040A		0x7F4F	/* EN_29LV040(A) */
+#define EN_29F002AT		0x7F92
+#define EN_29F002AB		0x7F97
 
 #define FUJITSU_ID		0x04	/* Fujitsu */
 /* MBM29F400TC_STRANGE has a value not mentioned in the data sheet and we
diff --git a/flashchips.c b/flashchips.c
index 2bd039d..71f2d8e 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -42,6 +42,9 @@ struct flashchip flashchips[] = {
 	 probe_jedec,	erase_chip_jedec, write_jedec},
 	{"At49F002(N)T",ATMEL_ID,	AT_49F002NT,	256, 256,
 	 probe_jedec,	erase_chip_jedec, write_jedec},
+	/* The EN29F002AT can do byte program at arbitrary boundaries. */
+	{"EN29F002AT",	EON_ID,		EN_29F002AT,	256, 256,
+	 probe_jedec,	erase_chip_jedec, write_jedec},
 	{"MBM29F400TC",	FUJITSU_ID,	MBM29F400TC_STRANGE,	512, 64 * 1024,
 	 probe_m29f400bt, erase_m29f400bt, write_linuxbios_m29f400bt},
 	{"MX29F002",	MX_ID,		MX_29F002,	256, 64 * 1024,
diff --git a/jedec.c b/jedec.c
index 30d0cda..9588751 100644
--- a/jedec.c
+++ b/jedec.c
@@ -4,6 +4,7 @@
  * Copyright (C) 2000 Silicon Integrated System Corporation
  * Copyright (C) 2006 Giampiero Giancipoli <gianci@email.it>
  * Copyright (C) 2006 coresystems GmbH <info@coresystems.de>
+ * Copyright (C) 2007 Carl-Daniel Hailfinger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -82,6 +83,7 @@ int probe_jedec(struct flashchip *flash)
 {
 	volatile uint8_t *bios = flash->virtual_memory;
 	uint8_t id1, id2;
+	uint32_t largeid1, largeid2;
 
 	/* Issue JEDEC Product ID Entry command */
 	*(volatile uint8_t *)(bios + 0x5555) = 0xAA;
@@ -98,6 +100,20 @@ int probe_jedec(struct flashchip *flash)
 	/* Read product ID */
 	id1 = *(volatile uint8_t *)bios;
 	id2 = *(volatile uint8_t *)(bios + 0x01);
+	largeid1 = id1;
+	largeid2 = id2;
+
+	/* Check if it is a continuation ID, this should be a while loop. */
+	if (id1 == 0x7F) {
+		largeid1 <<= 8;
+		id1 = *(volatile uint8_t *)(bios + 0x100);
+		largeid1 |= id1;
+	}
+	if (id2 == 0x7F) {
+		largeid2 <<= 8;
+		id2 = *(volatile uint8_t *)(bios + 0x101);
+		largeid2 |= id2;
+	}
 
 	/* Issue JEDEC Product ID Exit command */
 	*(volatile uint8_t *)(bios + 0x5555) = 0xAA;
@@ -107,8 +123,8 @@ int probe_jedec(struct flashchip *flash)
 	*(volatile uint8_t *)(bios + 0x5555) = 0xF0;
 	myusec_delay(40);
 
-	printf_debug("%s: id1 0x%x, id2 0x%x\n", __FUNCTION__, id1, id2);
-	if (id1 == flash->manufacture_id && id2 == flash->model_id)
+	printf_debug("%s: id1 0x%x, id2 0x%x\n", __FUNCTION__, largeid1, largeid2);
+	if (largeid1 == flash->manufacture_id && largeid2 == flash->model_id)
 		return 1;
 
 	return 0;