commit 89569d60e3aeeec651496b2e7a2e6064d782ab3b
author Nico Huber <nico.h@gmx.de> Thu Jan 12 23:31:40 2023 +0100
committer Nico Huber <nico.h@gmx.de> Sat Mar 09 10:30:24 2024 +0000
tree bf0c3951886de60086d32ff6e1a850adad926da6
parent 929d2e1b17a448d3352dbecb6a620ee0c1e65a58

memory_mapped: Reduce `decode_sizes` to a single `max_rom_decode`

We used to store the maximum decode size, i.e. the maximum memory-mapped
range of the flash chip, per bus type (Parallel, LPC, FWH, SPI). There
was no programmer in the tree that really made use of it, though:
* The chipset drivers usually focus on a single bus type. And even if
  they advertise the whole default set (PAR, LPC, FWH), they only pro-
  vide a maximum decode size for one of them. The latter is probably
  wrong, should really more than one bus type be supported.
* PCI and external programmers all support only a single bus type, with
  the exception of `serprog` which doesn't set a maximum decode size.

What made the distinction even less useful is that for some chips that
support multiple bus types, i.e. LPC+FWH, we can't even detect which
type it is. The existing code around this also only tried to provide
the best possible warning message at the expense of breaking the pro-
grammer abstraction.

Hence, unify the set of sizes into a single `max_rom_decode` property.
We store it inside the `registered_master` struct right away, to avoid
any more use of globals.

Change-Id: I2aaea18d5b4255eb843a625b016ee74bb145ed85
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.sourcearcade.org/c/flashprog/+/72531

cli_classic.c

diff --git a/cli_classic.c b/cli_classic.c
index 79159c3..fede2ca 100644
--- a/cli_classic.c
+++ b/cli_classic.c
@@ -189,48 +189,16 @@
 	return ret;
 }
 
-/* Returns the number of buses commonly supported by the current programmer and flash chip where the latter
- * can not be completely accessed due to size/address limits of the programmer. */
-static unsigned int count_max_decode_exceedings(const struct flashctx *flash,
-		const struct decode_sizes *max_rom_decode_)
+/* Returns true if the flash chip cannot be completely accessed due to size/address limits of the programmer. */
+static bool max_decode_exceeded(const struct registered_master *const mst, const struct flashctx *const flash)
 {
-	unsigned int limitexceeded = 0;
-	uint32_t size = flash->chip->total_size * 1024;
-	enum chipbustype buses = flash->mst->buses_supported & flash->chip->bustype;
+	if (flashprog_flash_getsize(flash) <= mst->max_rom_decode)
+		return false;
 
-	if ((buses & BUS_PARALLEL) && (max_rom_decode_->parallel < size)) {
-		limitexceeded++;
-		msg_pdbg("Chip size %u kB is bigger than supported "
-			 "size %u kB of chipset/board/programmer "
-			 "for %s interface, "
-			 "probe/read/erase/write may fail. ", size / 1024,
-			 max_rom_decode_->parallel / 1024, "Parallel");
-	}
-	if ((buses & BUS_LPC) && (max_rom_decode_->lpc < size)) {
-		limitexceeded++;
-		msg_pdbg("Chip size %u kB is bigger than supported "
-			 "size %u kB of chipset/board/programmer "
-			 "for %s interface, "
-			 "probe/read/erase/write may fail. ", size / 1024,
-			 max_rom_decode_->lpc / 1024, "LPC");
-	}
-	if ((buses & BUS_FWH) && (max_rom_decode_->fwh < size)) {
-		limitexceeded++;
-		msg_pdbg("Chip size %u kB is bigger than supported "
-			 "size %u kB of chipset/board/programmer "
-			 "for %s interface, "
-			 "probe/read/erase/write may fail. ", size / 1024,
-			 max_rom_decode_->fwh / 1024, "FWH");
-	}
-	if ((buses & BUS_SPI) && (max_rom_decode_->spi < size)) {
-		limitexceeded++;
-		msg_pdbg("Chip size %u kB is bigger than supported "
-			 "size %u kB of chipset/board/programmer "
-			 "for %s interface, "
-			 "probe/read/erase/write may fail. ", size / 1024,
-			 max_rom_decode_->spi / 1024, "SPI");
-	}
-	return limitexceeded;
+	msg_pdbg("Chip size %u kB is bigger than supported size %zu kB of\n"
+		 "chipset/board/programmer for memory-mapped interface, probe/read/erase/write\n"
+		 "may fail.\n", flash->chip->total_size, mst->max_rom_decode / KiB);
+	return true;
 }
 
 int main(int argc, char *argv[])
@@ -604,12 +572,15 @@
 	msg_pdbg("The following protocols are supported: %s.\n", tempstr);
 	free(tempstr);
 
+	struct registered_master *matched_master = NULL;
 	for (j = 0; j < registered_master_count; j++) {
 		startchip = 0;
 		while (chipcount < (int)ARRAY_SIZE(flashes)) {
 			startchip = probe_flash(&registered_masters[j], startchip, &flashes[chipcount], 0);
 			if (startchip == -1)
 				break;
+			if (chipcount == 0)
+				matched_master = &registered_masters[j];
 			chipcount++;
 			startchip++;
 		}
@@ -680,16 +651,7 @@
 
 	print_chip_support_status(fill_flash->chip);
 
-	unsigned int limitexceeded = count_max_decode_exceedings(fill_flash, &max_rom_decode);
-	if (limitexceeded > 0 && !force) {
-		enum chipbustype commonbuses = fill_flash->mst->buses_supported & fill_flash->chip->bustype;
-
-		/* Sometimes chip and programmer have more than one bus in common,
-		 * and the limit is not exceeded on all buses. Tell the user. */
-		if ((bitcount(commonbuses) > limitexceeded)) {
-			msg_pdbg("There is at least one interface available which could support the size of\n"
-				 "the selected flash chip.\n");
-		}
+	if (max_decode_exceeded(matched_master, fill_flash) && !force) {
 		msg_cerr("This flash chip is too big for this programmer (--verbose/-V gives details).\n"
 			 "Use --force/-f to override at your own risk.\n");
 		ret = 1;