[flashrom] [PATCH] Improve error messages, protect the user

[Carl-Daniel Hailfinger]

Disallow erase/write for known bad chips so people won't try without a
clear understanding. If we want them to test, we can tell them to
patch/edit flashchips.c.

If write/erase failed, warn the user to get help and not shutdown/reboot
the computer.

Warn that the result of a forced read is often garbage. Too many users
believed that a forced read meant that everything was fine.

Signed-off-by: Carl-Daniel Hailfinger

Index: flashrom-errormessages/flashrom.c
===================================================================
--- flashrom-errormessages/flashrom.c	(Revision 676)
+++ flashrom-errormessages/flashrom.c	(Arbeitskopie)
@@ -221,6 +221,7 @@
 {
    size_t size = flash->total_size * 1024;
    /* Flash registers live 4 MByte below the flash. */
+	/* FIXME: This is incorrect for nonstandard flashbase. */
    flash->virtual_registers = (chipaddr)programmer_map_flash_region("flash chip registers", (0xFFFFFFFF - 0x400000 - size + 1), size);
 }

@@ -475,6 +476,15 @@
    return 0;
 }

+void emergency_help_message()
+{
+	fprintf(stderr, "Your flash chip is in an unknown state.\n"
+		"Get help on IRC at irc.freenode.net channel #flashrom or\n"
+		"mail [e-mail]\n"
+		"------------------------------------------------------------\n"
+		"DO NOT REBOOT OR POWEROFF!\n");
+}
+
 void usage(const char *name)
 {
    printf("usage: %s [-VfLzhR] [-E|-r file|-w file|-v file] [-c chipname]\n"
@@ -743,6 +753,7 @@
    			printf("Run flashrom -L to view the hardware supported in this flashrom version.\n");
    			exit(1);
    		}
+			printf("Please note that forced reads most likely contain garbage.\n");
    		return read_flash(flashes[0], filename);
    	}
    	// FIXME: flash writes stay enabled!
@@ -808,14 +819,31 @@
    buf = (uint8_t *) calloc(size, sizeof(char));

if (erase_it) {
-		if (erase_flash(flash))
+		if (flash->tested & TEST_BAD_ERASE) {
+			fprintf(stderr, "Erase is not working on this chip. "
+				"Aborting.\n");
    		return 1;
+		}
+		if (erase_flash(flash)) {
+			emergency_help_message();
+			return 1;
+		}
    } else if (read_it) {
    	if (read_flash(flash, filename))
    		return 1;
    } else {
    	struct stat image_stat;

+		if (flash->tested & TEST_BAD_ERASE) {
+			fprintf(stderr, "Erase is not working on this chip "
+				"and erase is needed for write. Aborting.\n");
+			return 1;
+		}
+		if (flash->tested & TEST_BAD_WRITE) {
+			fprintf(stderr, "Write is not working on this chip. "
+				"Aborting.\n");
+			return 1;
+		}
    	if ((image = fopen(filename, "r")) == NULL) {
    		perror(filename);
    		exit(1);
@@ -854,14 +882,18 @@
    	ret = flash->write(flash, buf);
    	if (ret) {
    		fprintf(stderr, "FAILED!\n");
+			emergency_help_message();
    		return 1;
    	} else {
    		printf("COMPLETE.\n");
    	}
    }

-	if (verify_it)
+	if (verify_it) {
    	ret = verify_flash(flash, buf);
+		if (ret)
+			emergency_help_message();
+	}

programmer_shutdown();