[flashrom] [PATCH] Annotate evil twins

[Carl-Daniel Hailfinger]

Evil twins are chips with identical IDs and different/incompatible
characteristics (e.g. eraseblock layout, write strategy or size).
Annotate them so flashrom can tell the user that it's not a matter of
simply picking one of the chips in a list of multiple chips found.

This patch only touches the AMIC A25L40PT and A25L40PU.
I'm fairly sure there are more evil twins, but those two were touched
recently.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006 at gmx.net>

Index: flashrom-evil_twin/flash.h
===================================================================
--- flashrom-evil_twin/flash.h	(Revision 1096)
+++ flashrom-evil_twin/flash.h	(Arbeitskopie)
@@ -180,6 +180,14 @@
 #define FEATURE_ADDR_2AA	(1 << 2)
 #define FEATURE_ADDR_AAA	(2 << 2)
 #define FEATURE_ADDR_SHIFTED	(1 << 5)
+/* Evil twins are chips with the same ID and different erase/write
+ * characteristics. The second macro discards its arguments for now and allows
+ * human readable annotation while at the same time providing a zero cost
+ * simplified machine readable annotation. The first macro is there to check
+ * quickly if the chip has any evil twins.
+ */
+#define FEATURE_EVIL_TWIN	(1 << 6)
+#define FEATURE_EVIL_TWIN_OF(a,b) (1 << 6)
 
 struct flashchip {
 	const char *vendor;
Index: flashrom-evil_twin/flashchips.c
===================================================================
--- flashrom-evil_twin/flashchips.c	(Revision 1096)
+++ flashrom-evil_twin/flashchips.c	(Arbeitskopie)
@@ -1372,6 +1372,7 @@
 		.model_id	= AMIC_A25L40PT,
 		.total_size	= 512,
 		.page_size	= 256,
+		.feature_bits	= FEATURE_EVIL_TWIN_OF("AMIC", "A25L40PU"),
 		.tested		= TEST_OK_PRW,
 		.probe		= probe_spi_rdid4,
 		.probe_timing	= TIMING_ZERO,
@@ -1404,6 +1405,7 @@
 		.model_id	= AMIC_A25L40PU,
 		.total_size	= 512,
 		.page_size	= 256,
+		.feature_bits	= FEATURE_EVIL_TWIN_OF("AMIC", "A25L40PT"),
 		.tested		= TEST_OK_PRW,
 		.probe		= probe_spi_rdid4,
 		.probe_timing	= TIMING_ZERO,
Index: flashrom-evil_twin/cli_classic.c
===================================================================
--- flashrom-evil_twin/cli_classic.c	(Revision 1096)
+++ flashrom-evil_twin/cli_classic.c	(Arbeitskopie)
@@ -399,7 +399,8 @@
 	if (flashes[1]) {
 		printf("Multiple flash chips were detected:");
 		for (i = 0; i < ARRAY_SIZE(flashes) && flashes[i]; i++)
-			printf(" %s", flashes[i]->name);
+			printf("%s %s%s", i ? "," : "", flashes[i]->name,
+			       flashes[i]->feature_bits & FEATURE_EVIL_TWIN ? " (evil twin)" : "");
 		printf("\nPlease specify which chip to use with the -c <chipname> option.\n");
 		programmer_shutdown();
 		exit(1);


-- 
http://www.hailfinger.org/