Move implicit erase out of chip drivers

Flashrom had an implicit erase-on-write for most flash chip and
programmer drivers, but it was not entirely consistent.

Some drivers had their own hand-rolled partial update functionality
which made handling partial updates from generic code impossible.

Move implicit erase out of chip drivers, and kill some dead erase
functions at the same time. A full chip erase is now performed in the
generic code for all flash chips on write, and after that the whole chip
is written.

Corresponding to flashrom svn r1206.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>

1 files changed, 17 insertions, 9 deletions

diff --git a/flashrom.c b/flashrom.c
index e5e334c..2cf8075 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -1509,6 +1509,7 @@ int main(int argc, char *argv[])
 
 /* This function signature is horrible. We need to design a better interface,
  * but right now it allows us to split off the CLI code.
+ * Besides that, the function itself is a textbook example of abysmal code flow.
  */
 int doit(struct flashchip *flash, int force, char *filename, int read_it, int write_it, int erase_it, int verify_it)
 {
@@ -1563,12 +1564,7 @@ int doit(struct flashchip *flash, int force, char *filename, int read_it, int wr
 			programmer_shutdown();
 			return 1;
 		}
-	} else {
-		struct stat image_stat;
-
-		if (flash->unlock)
-			flash->unlock(flash);
-
+	} else if (write_it) {
 		if (flash->tested & TEST_BAD_ERASE) {
 			msg_cerr("Erase is not working on this chip "
 				"and erase is needed for write. ");
@@ -1590,6 +1586,18 @@ int doit(struct flashchip *flash, int force, char *filename, int read_it, int wr
 				msg_cerr("Continuing anyway.\n");
 			}
 		}
+		if (!flash->write) {
+			msg_cerr("Error: flashrom has no write function for this flash chip.\n");
+			programmer_shutdown();
+			return 1;
+		}
+		if (flash->unlock)
+			flash->unlock(flash);
+
+	}
+	if (write_it || verify_it) {
+		struct stat image_stat;
+
 		if ((image = fopen(filename, "rb")) == NULL) {
 			perror(filename);
 			programmer_shutdown();
@@ -1625,12 +1633,12 @@ int doit(struct flashchip *flash, int force, char *filename, int read_it, int wr
 	// ////////////////////////////////////////////////////////////
 
 	if (write_it) {
-		msg_cinfo("Writing flash chip... ");
-		if (!flash->write) {
-			msg_cerr("Error: flashrom has no write function for this flash chip.\n");
+		if (erase_flash(flash)) {
+			emergency_help_message();
 			programmer_shutdown();
 			return 1;
 		}
+		msg_cinfo("Writing flash chip... ");
 		ret = flash->write(flash, buf);
 		if (ret) {
 			msg_cerr("FAILED!\n");