dummyflasher: Wire variable size feature via opaque infra

Wire "variable size" feature in dummy programmer via opaque infra.
This patch fixes the broken build with CONFIG_DUMMY=no.

Dummyflasher registers opaque master for the case when it is
initialised with EMULATE_VARIABLE_SIZE. Dummy opaque master emulates
read/write/erase as simple memory operations over
`data->flashchip_contents`.

The feature works via "Opaque flash chip" in flashchips.c which has
one block eraser at the moment. If this changes in future, each block
eraser needs to be updated in `probe_variable_size`.

Fixes: https://ticket.coreboot.org/issues/365

TEST=the following scenarious run successfully

Testing build

$ make clean && make CONFIG_DUMMY=no
$ flashrom -h : dummy is not in the list
$ make clean && make CONFIG_EVERYTHING=yes
$ flashrom -h : dummy is in the list

Testing "variable size" feature

$ flashrom -p dummy:size=8388608,emulate=VARIABLE_SIZE -V
$ flashrom -p dummy:size=8388608,emulate=VARIABLE_SIZE
  -r /tmp/dump.bin -V
$ head -c 8388608 </dev/urandom >/tmp/image.bin
$ flashrom
  -p dummy:image=/tmp/image.bin,size=8388608,emulate=VARIABLE_SIZE
  -w /tmp/dump.bin -V

also same as above with erase_to_zero=yes

Testing standard flow

$ flashrom -p dummy:emulate=W25Q128FV -V
$ flashrom -p dummy:emulate=W25Q128FV -r /tmp/dump.bin -V
$ head -c 16777216 </dev/urandom >/tmp/image.bin
$ flashrom -p dummy:image=/tmp/image.bin,emulate=W25Q128FV
  -w /tmp/dump.bin -V

Testing invalid combination of programmer params (`init_data` fails
and prints error message which is WAI)

$ flashrom -p dummy:size=8388608 -V
-> init_data: size parameter is only valid for VARIABLE_SIZE chip.
$ flashrom -p dummy:emulate=VARIABLE_SIZE -V
-> init_data: the size parameter is not given.
$ flashrom -p dummy:emulate=W25Q128FV,erase_to_zero=yes -V
-> init_data: erase_to_zero parameter is not valid for real chip.

Change-Id: I76402bfdf8b1a75489e4509fec92c9a777d0cf58
Signed-off-by: Anastasia Klimchuk <aklm@chromium.org>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/64488
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>

dummyflasher.c

@@ -119,6 +119,72 @@ static int dummy_spi_write_256(struct flashctx *flash, const uint8_t *buf, unsig
 				 emu_data->spi_write_256_chunksize);
 }
 
+static int probe_variable_size(struct flashctx *flash)
+{
+	const struct emu_data *emu_data = flash->mst->opaque.data;
+
+	/* Skip the probing if we don't emulate "variable size" chip. */
+	if (!emu_data || emu_data->emu_chip != EMULATE_VARIABLE_SIZE)
+		return 0;
+
+	flash->chip->total_size = emu_data->emu_chip_size / 1024;
+	msg_cdbg("%s: set flash->total_size to %dK bytes.\n", __func__,
+	         flash->chip->total_size);
+
+	flash->chip->tested = TEST_OK_PREW;
+
+	if (emu_data->erase_to_zero)
+		flash->chip->feature_bits |= FEATURE_ERASED_ZERO;
+
+	/*
+	 * Update the first count of the block_eraser.
+	 * Opaque flash chip entry in flashchips.c has only one block eraser.
+	 *
+	 * If this changes in future, the code below needs to be adjusted
+	 * to update all block erasers.
+	 */
+	struct block_eraser *eraser = &flash->chip->block_erasers[0];
+	if (!eraser->block_erase)
+		return 1;
+
+	eraser->eraseblocks[0].count = 1;
+	eraser->eraseblocks[0].size = emu_data->emu_chip_size;
+	msg_cdbg("%s: eraser.size=%d, .count=%d\n",
+		 __func__, eraser->eraseblocks[0].size,
+		 eraser->eraseblocks[0].count);
+
+	return 1;
+}
+
+static int dummy_opaque_read(struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len)
+{
+	const struct emu_data *emu_data = flash->mst->opaque.data;
+
+	memcpy(buf, emu_data->flashchip_contents + start, len);
+
+	return 0;
+}
+
+static int dummy_opaque_write(struct flashctx *flash, const uint8_t *buf, unsigned int start, unsigned int len)
+{
+	struct emu_data *emu_data = flash->mst->opaque.data;
+
+	memcpy(emu_data->flashchip_contents + start, buf, len);
+	emu_data->emu_modified = 1;
+
+	return 0;
+}
+
+static int dummy_opaque_erase(struct flashctx *flash, unsigned int blockaddr, unsigned int blocklen)
+{
+	struct emu_data *emu_data = flash->mst->opaque.data;
+
+	memset(emu_data->flashchip_contents + blockaddr, emu_data->erase_to_zero ? 0x00 : 0xff, blocklen);
+	emu_data->emu_modified = 1;
+
+	return 0;
+}
+
 static void dummy_chip_writeb(const struct flashctx *flash, uint8_t val, chipaddr addr)
 {
 	msg_pspew("%s: addr=0x%" PRIxPTR ", val=0x%02x\n", __func__, addr, val);
@@ -270,7 +336,7 @@ static int erase_flash_data(struct emu_data *data, uint32_t start, uint32_t len)
 		return 1;
 	}
 
-	/* FIXME: take data->erase_to_zero into account. */
+	/* FIXME: Maybe use ERASED_VALUE(flash) instead of 0xff ? */
 	memset(data->flashchip_contents + start, 0xff, len);
 	data->emu_modified = 1;
 	return 0;
@@ -814,6 +880,13 @@ static const struct par_master par_master_dummyflasher = {
 		.chip_writen		= dummy_chip_writen,
 };
 
+static const struct opaque_master opaque_master_dummyflasher = {
+	.probe          = probe_variable_size,
+	.read           = dummy_opaque_read,
+	.write          = dummy_opaque_write,
+	.erase          = dummy_opaque_erase,
+};
+
 static int init_data(struct emu_data *data, enum chipbustype *dummy_buses_supported)
 {
 
@@ -827,7 +900,7 @@ static int init_data(struct emu_data *data, enum chipbustype *dummy_buses_suppor
 	bustext = extract_programmer_param("bus");
 	msg_pdbg("Requested buses are: %s\n", bustext ? bustext : "default");
 	if (!bustext)
-		bustext = strdup("parallel+lpc+fwh+spi");
+		bustext = strdup("parallel+lpc+fwh+spi+prog");
 	/* Convert the parameters to lowercase. */
 	tolower_string(bustext);
 
@@ -848,6 +921,10 @@ static int init_data(struct emu_data *data, enum chipbustype *dummy_buses_suppor
 		*dummy_buses_supported |= BUS_SPI;
 		msg_pdbg("Enabling support for %s flash.\n", "SPI");
 	}
+	if (strstr(bustext, "prog")) {
+		*dummy_buses_supported |= BUS_PROG;
+		msg_pdbg("Enabling support for %s flash.\n", "PROG");
+	}
 	if (*dummy_buses_supported == BUS_NONE)
 		msg_pdbg("Support for all flash bus types disabled.\n");
 	free(bustext);
@@ -1010,6 +1087,10 @@ static int init_data(struct emu_data *data, enum chipbustype *dummy_buses_suppor
 
 	tmp = extract_programmer_param("emulate");
 	if (!tmp) {
+		if (size != -1) {
+			msg_perr("%s: size parameter is only valid for VARIABLE_SIZE chip.\n", __func__);
+			return 1;
+		}
 		msg_pdbg("Not emulating any flash chip.\n");
 		/* Nothing else to do. */
 		return 0;
@@ -1107,6 +1188,10 @@ static int init_data(struct emu_data *data, enum chipbustype *dummy_buses_suppor
 		data->emu_jedec_ce_c7_size = data->emu_chip_size;
 		msg_pdbg("Emulating generic SPI flash chip (size=%d bytes)\n",
 		         data->emu_chip_size);
+	} else if (size != -1) {
+		msg_perr("%s: size parameter is only valid for VARIABLE_SIZE chip.\n", __func__);
+		free(tmp);
+		return 1;
 	}
 
 	if (data->emu_chip == EMULATE_NONE) {
@@ -1119,6 +1204,11 @@ static int init_data(struct emu_data *data, enum chipbustype *dummy_buses_suppor
 	/* Should emulated flash erase to zero (yes/no)? */
 	tmp = extract_programmer_param("erase_to_zero");
 	if (tmp) {
+		if (data->emu_chip != EMULATE_VARIABLE_SIZE) {
+			msg_perr("%s: erase_to_zero parameter is not valid for real chip.\n", __func__);
+			free(tmp);
+			return 1;
+		}
 		if (!strcmp(tmp, "yes")) {
 			msg_pdbg("Emulated chip will erase to 0x00\n");
 			data->erase_to_zero = 1;
@@ -1241,6 +1331,9 @@ dummy_init_out:
 		free(data);
 		return 1;
 	}
+
+	if (dummy_buses_supported & BUS_PROG)
+		register_opaque_master(&opaque_master_dummyflasher, data);
 	if (dummy_buses_supported & BUS_NONSPI)
 		register_par_master(&par_master_dummyflasher,
 				    dummy_buses_supported & BUS_NONSPI,
@@ -1251,49 +1344,6 @@ dummy_init_out:
 	return 0;
 }
 
-int probe_variable_size(struct flashctx *flash)
-{
-	unsigned int i;
-	const struct emu_data *emu_data = flash->mst->spi.data;
-
-	/* Skip the probing if we don't emulate this chip. */
-	if (!emu_data || emu_data->emu_chip != EMULATE_VARIABLE_SIZE)
-		return 0;
-
-	/*
-	 * This will break if one day flashctx becomes read-only.
-	 * Once that happens, we need to have special hacks in functions:
-	 *
-	 *     erase_and_write_flash() in flashrom.c
-	 *     do_read()
-	 *     handle_romentries()
-	 *     ...
-	 *
-	 * Search "total_size * 1024" in code.
-	 */
-	flash->chip->total_size = emu_data->emu_chip_size / 1024;
-	msg_cdbg("%s: set flash->total_size to %dK bytes.\n", __func__,
-	         flash->chip->total_size);
-
-	if (emu_data->erase_to_zero)
-		flash->chip->feature_bits |= FEATURE_ERASED_ZERO;
-
-	/* Update the first count of each of the block_erasers. */
-	for (i = 0; i < NUM_ERASEFUNCTIONS; i++) {
-		struct block_eraser *eraser = &flash->chip->block_erasers[i];
-		if (!eraser->block_erase)
-			break;
-
-		eraser->eraseblocks[0].count = 1;
-		eraser->eraseblocks[0].size = emu_data->emu_chip_size;
-		msg_cdbg("%s: eraser.size=%d, .count=%d\n",
-		         __func__, eraser->eraseblocks[0].size,
-		         eraser->eraseblocks[0].count);
-	}
-
-	return 1;
-}
-
 const struct programmer_entry programmer_dummy = {
 	.name			= "dummy",
 	.type			= OTHER,

flashchips.c

@@ -19962,28 +19962,6 @@ const struct flashchip flashchips[] = {
 		.read		= NULL,
 	},
 
-	{
-		.vendor		= "Generic",
-		.name		= "Variable Size SPI chip",
-		.bustype	= BUS_SPI,
-		.manufacture_id	= PROGMANUF_ID,
-		.model_id	= PROGDEV_ID,
-		.total_size	= 64,  /* This size is set temporarily */
-		.page_size	= 256,
-		.feature_bits	= FEATURE_4BA_READ | FEATURE_4BA_WRITE,
-		.tested		= TEST_OK_PREW,
-		.probe		= probe_variable_size,
-		.block_erasers	=
-		{
-			{
-				.eraseblocks = { {64 * 1024, 1} },
-				.block_erase = spi_block_erase_c7,
-			}
-		},
-		.write		= spi_chip_write_256,
-		.read		= spi_chip_read,
-	},
-
 	{
 		.vendor		= "Generic",
 		.name		= "unknown SPI chip (RDID)",

include/chipdrivers.h

@@ -201,9 +201,6 @@ int erase_sector_stm50(struct flashctx *flash, unsigned int block, unsigned int
 int probe_en29lv640b(struct flashctx *flash);
 int write_en29lv640b(struct flashctx *flash, const uint8_t *buf, unsigned int start, unsigned int len);
 
-/* dummyflasher.c */
-int probe_variable_size(struct flashctx *flash);
-
 /* edi.c */
 int edi_chip_block_erase(struct flashctx *flash, unsigned int page, unsigned int size);
 int edi_chip_write(struct flashctx *flash, const uint8_t *buf, unsigned int start, unsigned int len);