jtagonizer

commit d8209428eb028a358f41c50ee3200ea5202550ca
parent 5bdbf977007e9c52b171e979f0cbfeae1ec3090d
Author: Brian Swetland <swetland@frotz.net>
Date:   Mon, 22 Sep 2014 19:27:30 -0700

add enumeration and selection support

Diffstat:
M
jtag-core.c
 | 
148
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------
M
jtag.h
 | 
25
+++++++++++++++++++++++++

2 files changed, 161 insertions(+), 12 deletions(-)
diff --git a/jtag-core.c b/jtag-core.c
@@ -18,6 +18,30 @@
 
 #include "jtag-driver.h"
 
+
+#define ZYNQID(code)	((0x1B<<21)|(0x9<<17)|((code)<<12)|(0x49<<1)|1)
+#define ZYNQMASK	0x0FFFFFFF
+
+static JTAG_INFO LIBRARY[] = {
+	{ 0x4ba00477, 0xFFFFFFFF, 4, "Cortex A9" },
+	{ ZYNQID(0x02), ZYNQMASK, 6, "xc7x010" },
+	{ ZYNQID(0x1b), ZYNQMASK, 6, "xc7x015" },
+	{ ZYNQID(0x07), ZYNQMASK, 6, "xc7x020" },
+	{ ZYNQID(0x0c), ZYNQMASK, 6, "xc7x030" },
+	{ ZYNQID(0x11), ZYNQMASK, 6, "xc7x045" },
+	{ 0x13631093, 0xFFFFFFFF, 6, "xc7a100t" },
+};
+
+JTAG_INFO *jtag_lookup_device(unsigned idcode) {
+	int n;
+	for (n = 0; n < (sizeof(LIBRARY)/sizeof(LIBRARY[0])); n++) {
+		if ((idcode & LIBRARY[n].idmask) == LIBRARY[n].idcode) {
+			return LIBRARY + n;
+		}
+	}
+	return NULL;
+}
+
 #define TRACE_STATEMACHINE 0
 
 // configuration and state or IR or DR
@@ -30,6 +54,8 @@ typedef struct JREG {
 	u32 idlestate;
 } JREG;
 
+#define DEVMAX 32
+
 // configuration and state of JTAG
 struct JTAG {
 	JDRV *drv;
@@ -39,6 +65,9 @@ struct JTAG {
 	JREG dr;
 
 	u32 state;
+
+	int devcount;
+	JTAG_INFO devinfo[DEVMAX];
 };
 
 #define _setspeed(khz) \
@@ -52,8 +81,22 @@ struct JTAG {
 #define _close() \
 	jtag->vt->close(jtag->drv)
 
-static u8 ZEROS[32];
-static u8 ONES[32];
+static u8 ONES[1024];
+
+void jtag_clear_state(JTAG *jtag) {
+	jtag->ir.idlestate = JTAG_IDLE;
+	jtag->ir.scanstate = JTAG_IRSHIFT;
+	jtag->dr.idlestate = JTAG_IDLE;
+	jtag->dr.scanstate = JTAG_DRSHIFT;
+	jtag->ir.prebits = 0;
+	jtag->ir.precount = 0;
+	jtag->ir.postbits = 0;
+	jtag->ir.postcount = 0;
+	jtag->dr.prebits = 0;
+	jtag->dr.precount = 0;
+	jtag->dr.postbits = 0;
+	jtag->dr.postcount = 0;
+}
 
 int jtag_init(JTAG **_jtag, JDRV *drv, JDVT *vt) {
 	JTAG *jtag;
@@ -63,13 +106,9 @@ int jtag_init(JTAG **_jtag, JDRV *drv, JDVT *vt) {
 	memset(jtag, 0, sizeof(JTAG));
 	jtag->drv = drv;
 	jtag->vt = vt;
-	jtag->ir.idlestate = JTAG_IDLE;
-	jtag->ir.scanstate = JTAG_IRSHIFT;
-	jtag->dr.idlestate = JTAG_IDLE;
-	jtag->dr.scanstate = JTAG_DRSHIFT;
+	jtag_clear_state(jtag);
 	*_jtag = jtag;
-	memset(ZEROS, 0x00, 32);
-	memset(ONES, 0xFF, 32);
+	memset(ONES, 0xFF, sizeof(ONES));
 	return 0;
 }
 
@@ -91,19 +130,19 @@ void jtag_set_dr_idle(JTAG *jtag, unsigned state) {
 }
 
 void jtag_set_ir_prefix(JTAG *jtag, unsigned count, const void *bits) {
-	jtag->ir.prebits = (u8*) bits;
+	jtag->ir.prebits = count ? (u8*) bits : 0;
 	jtag->ir.precount = count;
 }
 void jtag_set_ir_postfix(JTAG *jtag, unsigned count, const void *bits) {
-	jtag->ir.postbits = (u8*) bits;
+	jtag->ir.postbits = count ? (u8*) bits : 0;
 	jtag->ir.postcount = count;
 }
 void jtag_set_dr_prefix(JTAG *jtag, unsigned count, const void *bits) {
-	jtag->dr.prebits = (u8*) bits;
+	jtag->dr.prebits = count ? (u8*) bits : 0;
 	jtag->dr.precount = count;
 }
 void jtag_set_dr_postfix(JTAG *jtag, unsigned count, const void *bits) {
-	jtag->dr.postbits = (u8*) bits;
+	jtag->dr.postbits = count ? (u8*) bits : 0;
 	jtag->dr.postcount = count;
 }
 
@@ -252,3 +291,88 @@ void jtag_dr_io(JTAG *jtag, unsigned count, const void *wbits, void *rbits) {
 int jtag_commit(JTAG *jtag) {
 	return _commit();
 }
+
+int jtag_enumerate(JTAG *jtag) {
+	JTAG_INFO *info;
+	u32 data[DEVMAX];
+	int n;
+
+	jtag_clear_state(jtag);
+	jtag->devcount = 0;
+
+	jtag_goto(jtag, JTAG_RESET);
+	jtag_goto(jtag, JTAG_RESET);
+	jtag_goto(jtag, JTAG_RESET);
+	jtag_dr_io(jtag, DEVMAX * 4 * 8, ONES, data);
+	if (jtag_commit(jtag)) {
+		return -1;
+	}
+	for (n = 0; n < DEVMAX; n++) {
+
+		if (data[n] == 0xffffffff) {
+			if (n == 0) {
+				fprintf(stderr, "no devices found\n");
+				return -1;
+			}
+			jtag->devcount = n;
+			return n;
+		}
+		if (!(data[n] & 1)) {
+			fprintf(stderr, "device %d has no idcode\n", n);
+			return -1;
+		}
+		if ((info = jtag_lookup_device(data[n])) == NULL) {
+			fprintf(stderr, "device %d (id %08x) unknown\n",
+				n, (unsigned) data[n]);
+			return -1;
+		}
+		memcpy(jtag->devinfo + n, info, sizeof(JTAG_INFO));
+		fprintf(stderr, "device %02d idcode %08x '%s'\n",
+			n, info->idcode, info->name);
+	}
+	fprintf(stderr, "too many devices\n");
+	return -1;
+}
+
+JTAG_INFO *jtag_get_nth_device(JTAG *jtag, int n) {
+	if ((n >= jtag->devcount) || (n < 0)) {
+		return NULL;
+	}
+	return jtag->devinfo + n;
+}
+
+int jtag_select_device_nth(JTAG *jtag, int num) {
+	u32 irpre = 0;
+	u32 irpost = 0;
+	u32 drpre = 0;
+	u32 drpost = 0;
+	int n;
+	if ((num >= jtag->devcount) || (num < 0)) {
+		return -1;
+	}
+	for (n = 0; n < jtag->devcount; n++) {
+		if (n < num) {
+			irpre += jtag->devinfo[n].irsize;
+			drpre += 1;
+		} else if (n > num) {
+			irpost += jtag->devinfo[n].irsize;
+			drpost += 1;
+		}
+	}
+	jtag_set_ir_prefix(jtag, irpre, ONES);
+	jtag_set_ir_postfix(jtag, irpost, ONES);
+	jtag_set_dr_prefix(jtag, drpre, ONES);
+	jtag_set_dr_postfix(jtag, drpost, ONES);
+	return 0;
+}
+
+int jtag_select_device(JTAG *jtag, unsigned idcode) {
+	int n;
+	for (n = 0; n < jtag->devcount; n++) {
+		if (jtag->devinfo[n].idcode == idcode) {
+			return jtag_select_device_nth(jtag, n);
+		}
+	}
+	return -1;
+}
+
diff --git a/jtag.h b/jtag.h
@@ -52,6 +52,10 @@ void jtag_set_ir_postfix(JTAG *jtag, unsigned count, const void *bits);
 void jtag_set_dr_prefix(JTAG *jtag, unsigned count, const void *bits);
 void jtag_set_dr_postfix(JTAG *jtag, unsigned count, const void *bits);
 
+// clear all prefix/postfix patterns and return to default
+// idle states
+void jtag_clear_state(JTAG *jtag);
+
 // Move jtag state machine from current state to new state.
 // Moving to JTAG_RESET will work even if current state
 // is out of sync.
@@ -69,4 +73,25 @@ void jtag_dr_io(JTAG *jtag, unsigned count, const void *wbits, void *rbits);
 
 int jtag_commit(JTAG *jtag);
 
+typedef struct {
+	unsigned idcode;
+	unsigned idmask;
+	unsigned irsize;
+	const char *name;
+} JTAG_INFO;
+
+// reset the bus and probe it
+// returns number of devices detected, negative on error
+int jtag_enumerate(JTAG *jtag);
+
+// get information about the nth device on the chain
+JTAG_INFO *jtag_get_nth_device(JTAG *jtag, int n);
+
+// configure for communication with a single device
+// will setup ir/dr prefix and postfix
+int jtag_select_device(JTAG *jtag, unsigned idcode);
+
+// select by position in scan chain
+int jtag_select_device_nth(JTAG *jtag, int n);
+
 #endif