qdl: add support for dry run execution

This mode assists in validating the `rawprogram_.xml` and `patch_.xml`
files, as well as the Firehose commands that are expected to be sent
to the Firehose programmer.

Dry run implementation is also expected to be extended for
the Digests Table generation required for Firehose Validated Image
Programming (VIP).

Example of usage:
$ qdl --dry-run --serial=0AA94EFD --debug prog_firehose_ddr.elf rawprogram*.xml patch*.xml
qdl version v2.1-24-g30ac3a8-dirty
This is a dry-run execution of QDL. No actual flashing has been performed
waiting for programmer...
FIREHOSE WRITE: <?xml version="1.0"?>
<data><configure MemoryName="ufs" MaxPayloadSizeToTargetInBytes="1048576"
verbose="0" ZLPAwareHost="1" SkipStorageInit="0"/></data>

FIREHOSE WRITE: <?xml version="1.0"?>
<data><configure MemoryName="ufs" MaxPayloadSizeToTargetInBytes="0"
verbose="0" ZLPAwareHost="1" SkipStorageInit="0"/></data>

accepted max payload size: 0
FIREHOSE WRITE: <?xml version="1.0"?>
<data><program SECTOR_SIZE_IN_BYTES="4096" num_partition_sectors="131072"
physical_partition_number="0" start_sector="6" filename="efi.bin"/></data>

Signed-off-by: Igor Opaniuk <igor.opaniuk@oss.qualcomm.com>

Makefile

@@ -6,10 +6,10 @@ CFLAGS += -O2 -Wall -g `pkg-config --cflags libxml-2.0 libusb-1.0`
 LDFLAGS += `pkg-config --libs libxml-2.0 libusb-1.0`
 prefix := /usr/local
 
-QDL_SRCS := firehose.c io.c qdl.c sahara.c util.c patch.c program.c read.c ufs.c usb.c ux.c oscompat.c
+QDL_SRCS := firehose.c io.c qdl.c sahara.c util.c patch.c program.c read.c sim.c ufs.c usb.c ux.c oscompat.c
 QDL_OBJS := $(QDL_SRCS:.c=.o)
 
-RAMDUMP_SRCS := ramdump.c sahara.c io.c usb.c util.c ux.c oscompat.c
+RAMDUMP_SRCS := ramdump.c sahara.c io.c sim.c usb.c util.c ux.c oscompat.c
 RAMDUMP_OBJS := $(RAMDUMP_SRCS:.c=.o)
 
 KS_OUT := ks

firehose.c

@@ -146,6 +146,10 @@ static int firehose_read(struct qdl_device *qdl, int timeout_ms,
 	gettimeofday(&now, NULL);
 	timeradd(&now, &delta, &timeout);
 
+	/* In simulation mode we don't expent to read and parse any responses */
+	if (qdl->dev_type == QDL_DEVICE_SIM)
+		return 0;
+
 	do {
 		n = qdl_read(qdl, buf, sizeof(buf), 100);
 		if (n <= 0) {
@@ -298,7 +302,12 @@ static int firehose_configure(struct qdl_device *qdl, bool skip_storage_init, co
 			return -1;
 		}
 
-		max_payload_size = size;
+		/*
+		 * Simulated target doesn't provide any valid payload size, so
+		 * for QDL_DEVICE_SIM dev type we keep old max_payload_size value
+		 */
+		if (qdl->dev_type != QDL_DEVICE_SIM)
+			max_payload_size = size;
 	}
 
 	ux_debug("accepted max payload size: %zu\n", max_payload_size);

io.c

@@ -36,6 +36,9 @@ struct qdl_device *qdl_init(enum QDL_DEVICE_TYPE type)
 	if (type == QDL_DEVICE_USB)
 		return usb_init();
 
+	if (type == QDL_DEVICE_SIM)
+		return sim_init();
+
 	return NULL;
 }
 

qdl.c

@@ -107,7 +107,7 @@ static void print_usage(void)
 {
 	extern const char *__progname;
 	fprintf(stderr,
-		"%s [--debug] [--version] [--allow-missing] [--storage <emmc|nand|ufs>] [--finalize-provisioning] [--include <PATH>] [--serial <NUM>] [--out-chunk-size <SIZE>] <prog.mbn> [<program> <patch> ...]\n",
+		"%s [--debug] [--dry-run] [--version] [--allow-missing] [--storage <emmc|nand|ufs>] [--finalize-provisioning] [--include <PATH>] [--serial <NUM>] [--out-chunk-size <SIZE>] <prog.mbn> [<program> <patch> ...]\n",
 		__progname);
 }
 
@@ -140,6 +140,7 @@ int main(int argc, char **argv)
 		{"storage", required_argument, 0, 's'},
 		{"allow-missing", no_argument, 0, 'f'},
 		{"allow-fusing", no_argument, 0, 'c'},
+		{"dry-run", no_argument, 0, 'n'},
 		{0, 0, 0, 0}
 	};
 
@@ -148,6 +149,9 @@ int main(int argc, char **argv)
 		case 'd':
 			qdl_debug = true;
 			break;
+		case 'n':
+			qdl_dev_type = QDL_DEVICE_SIM;
+			break;
 		case 'v':
 			print_version();
 			return 0;

qdl.h

@@ -13,6 +13,7 @@
 enum QDL_DEVICE_TYPE
 {
 	QDL_DEVICE_USB,
+        QDL_DEVICE_SIM,
 };
 
 struct qdl_device
@@ -40,6 +41,7 @@ int qdl_write(struct qdl_device *qdl, const void *buf, size_t len);
 void qdl_set_out_chunk_size(struct qdl_device *qdl, long size);
 
 struct qdl_device *usb_init(void);
+struct qdl_device *sim_init(void);
 
 int firehose_run(struct qdl_device *qdl, const char *incdir, const char *storage, bool allow_missing);
 int sahara_run(struct qdl_device *qdl, char *img_arr[], bool single_image,

sahara.c

@@ -469,6 +469,13 @@ int sahara_run(struct qdl_device *qdl, char *img_arr[], bool single_image,
 	bool done = false;
 	int n;
 
+	/*
+	 * Don't need to do anything in simulation mode with Sahara,
+	 * we care only about Firehose protocol
+	 */
+	if (qdl->dev_type == QDL_DEVICE_SIM)
+		return 0;
+
 	while (!done) {
 		n = qdl_read(qdl, buf, sizeof(buf), 1000);
 		if (n < 0)

sim.c

@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2025, Qualcomm Innovation Center, Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its contributors
+ * may be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <stdlib.h>
+#include <string.h>
+
+#include "qdl.h"
+
+struct qdl_device_sim
+{
+	struct qdl_device base;
+};
+
+static int sim_open(struct qdl_device *qdl, const char *serial)
+{
+	ux_info("This is a dry-run execution of QDL. No actual flashing has been performed\n");
+
+	return 0;
+}
+
+static void sim_close(struct qdl_device *qdl)
+{
+	return;
+}
+
+static int sim_read(struct qdl_device *qdl, void *buf, size_t len, unsigned int timeout)
+{
+	return len;
+}
+
+static int sim_write(struct qdl_device *qdl, const void *buf, size_t len)
+{
+	return len;
+}
+
+static void sim_set_out_chunk_size(struct qdl_device *qdl, long size)
+{
+	return;
+}
+
+struct qdl_device *sim_init(void)
+{
+	struct qdl_device *qdl = malloc(sizeof(struct qdl_device_sim));
+	if (!qdl)
+		return NULL;
+
+	memset(qdl, 0, sizeof(struct qdl_device_sim));
+
+	qdl->dev_type = QDL_DEVICE_SIM;
+	qdl->open = sim_open;
+	qdl->read = sim_read;
+	qdl->write = sim_write;
+	qdl->close = sim_close;
+	qdl->set_out_chunk_size = sim_set_out_chunk_size;
+
+	return qdl;
+}