swd_scan: Add '-m' as targetid argument to swd_scan to prepare multi-drop.

In a real multi-drop setup, the device to use must be specified.

src/command.c

@@ -219,8 +219,9 @@ static bool cmd_jtag_scan(target *t, int argc, char **argv)
 bool cmd_swdp_scan(target *t, int argc, char **argv)
 {
 	(void)t;
-	(void)argc;
+	volatile uint32_t targetid = 0;
-	(void)argv;
+	if (argc > 1)
+		targetid  = strtol(argv[1], NULL, 0);
 	if (platform_target_voltage())
 		gdb_outf("Target voltage: %s\n", platform_target_voltage());
 
@@ -231,9 +232,9 @@ bool cmd_swdp_scan(target *t, int argc, char **argv)
 	volatile struct exception e;
 	TRY_CATCH (e, EXCEPTION_ALL) {
 #if PC_HOSTED == 1
-		devs = platform_adiv5_swdp_scan();
+		devs = platform_adiv5_swdp_scan(targetid);
 #else
-		devs = adiv5_swdp_scan();
+		devs = adiv5_swdp_scan(targetid);
 #endif
 		}
 	switch (e.type) {

src/include/target.h

@@ -35,10 +35,10 @@ typedef uint32_t target_addr;
 struct target_controller;
 
 #if PC_HOSTED == 1
-int platform_adiv5_swdp_scan(void);
+int platform_adiv5_swdp_scan(uint32_t targetid);
 int platform_jtag_scan(const uint8_t *lrlens);
 #endif
-int adiv5_swdp_scan(void);
+int adiv5_swdp_scan(uint32_t targetid);
 int jtag_scan(const uint8_t *lrlens);
 
 int target_foreach(void (*cb)(int i, target *t, void *context), void *context);

src/platforms/hosted/platform.c

@@ -1,7 +1,7 @@
 /*
  * This file is part of the Black Magic Debug project.
  *
- * Copyright (C) 2020 Uwe Bonnes (bon@elektron.ikp.physik.tu-darmstadt.de)
+ * Copyright (C) 2020- 2021 Uwe Bonnes (bon@elektron.ikp.physik.tu-darmstadt.de)
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -119,14 +119,16 @@ void platform_init(int argc, char **argv)
 	exit(ret);
 }
 
-int platform_adiv5_swdp_scan(void)
+int platform_adiv5_swdp_scan(uint32_t targetid)
 {
 	info.is_jtag = false;
 	platform_max_frequency_set(cl_opts.opt_max_swj_frequency);
+	if (targetid && (info.bmp_type != BMP_TYPE_BMP))
+		DEBUG_WARN("Ignoring TARGETID for now!\n");
 	switch (info.bmp_type) {
 	case BMP_TYPE_BMP:
 	case BMP_TYPE_LIBFTDI:
-		return adiv5_swdp_scan();
+		return adiv5_swdp_scan(targetid);
 		break;
 	case BMP_TYPE_STLINKV2:
 	{

src/platforms/pc/cl_utils.c

@@ -165,6 +165,7 @@ static void cl_help(char **argv)
 	DEBUG_WARN("\t-p\t\t: Supplies power to the target (where applicable)\n");
 	DEBUG_WARN("\t-R\t\t: Reset device\n");
 	DEBUG_WARN("\t-H\t\t: Do not use high level commands (BMP-Remote)\n");
+	DEBUG_WARN("\t-m <target>\t: Use (target)id for SWD multi-drop.\n");
 	DEBUG_WARN("\t-M <string>\t: Run target specific monitor commands. Quote multi\n");
 	DEBUG_WARN("\t\t\t  word strings. Run \"-M help\" for help.\n");
 	DEBUG_WARN("Flash operation modifiers options:\n");
@@ -183,7 +184,7 @@ void cl_init(BMP_CL_OPTIONS_t *opt, int argc, char **argv)
 	opt->opt_flash_size = 16 * 1024 *1024;
 	opt->opt_flash_start = 0xffffffff;
 	opt->opt_max_swj_frequency = 4000000;
-	while((c = getopt(argc, argv, "eEhHv:d:f:s:I:c:Cln:M:tVtTa:S:jpP:rR")) != -1) {
+	while((c = getopt(argc, argv, "eEhHv:d:f:s:I:c:Cln:m:M:tVtTa:S:jpP:rR")) != -1) {
 		switch(c) {
 		case 'c':
 			if (optarg)
@@ -270,6 +271,10 @@ void cl_init(BMP_CL_OPTIONS_t *opt, int argc, char **argv)
 			if (optarg)
 				opt->opt_target_dev = strtol(optarg, NULL, 0);
 			break;
+		case 'm':
+			if (optarg)
+				opt->opt_targetid = strtol(optarg, NULL, 0);
+			break;
 		case 'M':
 			opt->opt_mode = BMP_MODE_MONITOR;
 			if (optarg)
@@ -347,7 +352,7 @@ int cl_execute(BMP_CL_OPTIONS_t *opt)
 	if (opt->opt_usejtag) {
 		num_targets = platform_jtag_scan(NULL);
 	} else {
-		num_targets = platform_adiv5_swdp_scan();
+		num_targets = platform_adiv5_swdp_scan(opt->opt_targetid);
 	}
 	if (!num_targets) {
 		DEBUG_WARN("No target found\n");

src/platforms/pc/cl_utils.h

@@ -1,7 +1,7 @@
 /*
  * This file is part of the Black Magic Debug project.
  *
- * Copyright (C) 2019 - 2020  Uwe Bonnes
+ * Copyright (C) 2019 - 2021  Uwe Bonnes
  * Written by Uwe Bonnes (bon@elektron.ikp.physik.tu-darmstadt.de)
  *
  * This program is free software: you can redistribute it and/or modify
@@ -49,6 +49,7 @@ typedef struct BMP_CL_OPTIONS_s {
 	char *opt_flash_file;
 	char *opt_device;
 	char *opt_serial;
+	uint32_t opt_targetid;
 	char *opt_ident_string;
 	int  opt_position;
 	char *opt_cable;

src/target/adiv5_swdp.c

@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2011  Black Sphere Technologies Ltd.
  * Written by Gareth McMullin <gareth@blacksphere.co.nz>
+ * Copyright (C) 2020- 2021 Uwe Bonnes (bon@elektron.ikp.physik.tu-darmstadt.de)
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -33,10 +34,10 @@
 #define SWDP_ACK_WAIT  0x02
 #define SWDP_ACK_FAULT 0x04
 
-int adiv5_swdp_scan(void)
+int adiv5_swdp_scan(uint32_t targetid)
 {
 	uint32_t ack;
-
+	(void) targetid;
 	target_list_free();
 #if PC_HOSTED == 1
 	if (platform_swdptap_init()) {