some switch work

Makefile

@@ -22,7 +22,7 @@ all: new_fp fp2bit bit2fp draw_svg_tiles \
 
 autotest: autotest.o $(MODEL_OBJ) floorplan.o control.o helper.o model.h
 
-autotest.c: model.h floorplan.h control.h
+autotest.o: model.h floorplan.h control.h
 
 new_fp: new_fp.o $(MODEL_OBJ) floorplan.o helper.o control.o
 

README

@@ -4,15 +4,22 @@ Design Principles
 - plain C, no C++
 - simple Makefiles
 - text-based file formats
-- no documentation - please read the sources
 - automatic test suite
+- public domain software
+
+Introduction
+ todo
+
+FAQ
+ todo
 
 Libraries
 
-- libfpga-test       test harness for model, control and design
+- libfpga-test       autotest suite
-- libfpga-model      memory-only representation of an FPGA
+- libfpga-cores      reusable cores
-- libfpga-control    programmatic access to libfpga-model
 - libfpga-design     larger design elements on top of libfpga-control
+- libfpga-control    programmatic access to libfpga-model
+- libfpga-model      memory-only representation of an FPGA
 - libfpga-floorplan  reads and writes .fp floorplan files
 - libfpga-bit        reads and writes .bit bitstream files
 
@@ -40,13 +47,14 @@ TODO (as of 2012-08, expected time to delivery: months to years
 * smarter autotester that can remember and verify groups of tests,
   automatically oversee test execution, etc.
 * 3 Debian packages: libfpga, libfpga-doc, fpgatools
-* correct auto-crc calculation in .bit file
+* auto-crc calculation in .bit file
 * many more cases in logic block configuration
 * configuration of bram and macc blocks, bram initialization data
 * routing switches
 * many more cases in model of switches and inter-tile connections
 * write standard design elements for libfpga-design library
 * support lm32 or openrisc core, either via libfpga or iverilog backend
+* ipv6 or vnc in hardware?
 * iverilog fpga backend
 
 ChangeLog

autotest.c

@@ -108,18 +108,16 @@ static const char* s_spaces = "                                              ";
 static int printf_switchtree(struct fpga_model* model, int y, int x,
 	const char* start, int indent)
 {
-	int i, idx, conn_to_y, conn_to_x, rc;
+	int i, idx, conn_to_y, conn_to_x, num_dests, connpt_dests_o, rc;
 	const char* to_str;
 
 	printf("%.*sy%02i x%02i %s\n", indent, s_spaces, y, x, start);
-	for (i = 0;; i++) {
+	num_dests = fpga_connpt_lookup(model, y, x, start, &connpt_dests_o);
-		idx = fpga_conn_dest(model, y, x, start, i);
+	for (i = 0; i < num_dests; i++) {
-		if (idx == NO_CONN)
-			break;
 		if (!i)
 			printf("%.*s| connects to:\n", indent, s_spaces);
-		to_str = fpga_conn_to(model, y, x,
+		to_str = fpga_conn_dest(model, y, x,
-			idx, &conn_to_y, &conn_to_x);
+			connpt_dests_o + i, &conn_to_y, &conn_to_x);
 		printf("%.*s  y%02i x%02i %s\n", indent, s_spaces,
 			conn_to_y, conn_to_x, to_str);
 	}
@@ -151,16 +149,16 @@ static int printf_switchtree(struct fpga_model* model, int y, int x,
 fail:
 	return rc;
 }
+
 int main(int argc, char** argv)
 {
 	struct fpga_model model;
 	struct fpga_device* P46_dev, *P48_dev, *logic_dev;
-	int P46_y, P46_x, P46_idx, P48_y, P48_x, P48_idx, i, sw_idx, rc;
+	int P46_y, P46_x, P46_idx, P48_y, P48_x, P48_idx, rc;
-	const char* str;
-	char tmp_str[128];
 	struct test_state tstate;
-	const char* conn_to_str;
+	struct sw_chain chain;
-	int conn_idx, conn_to_y, conn_to_x;
+	struct swchain_conns conns;
+	char tmp_str[128];
 
 	printf("\n");
 	printf("O fpgatools automatic test suite. Be welcome and be "
@@ -219,46 +217,74 @@ int main(int argc, char** argv)
 	if (rc) goto fail;
 
 	printf("P46 I pinw %s\n", P46_dev->iob.pinw_out_I);
-	sw_idx = fpga_switch_first(&model, P46_y, P46_x,
+	conns.model = &model;
-		P46_dev->iob.pinw_out_I, SW_FROM);
+	conns.y = P46_y;
-	while (sw_idx != NO_SWITCH) {
+	conns.x = P46_x;
-		str = fpga_switch_str(&model, P46_y, P46_x, sw_idx, SW_TO);
+	conns.start_switch = P46_dev->iob.pinw_out_I;
-		if (!str) FAIL(EINVAL);
+	while (fpga_switch_conns_enum(&conns) != NO_CONN) {
-		strcpy(tmp_str, str); // ringbuffer too small for long use
+
-		printf(" from %s to %s\n", P46_dev->iob.pinw_out_I, tmp_str);
+		if (is_aty(Y_TOP_INNER_IO|Y_BOT_INNER_IO, &model, conns.dest_y)) {
-		for (i = 0;; i++) {
+			struct swchain_conns conns2;
-			conn_idx = fpga_conn_dest(&model, P46_y, P46_x, tmp_str, i);
+
-			if (conn_idx == NO_CONN)
+			printf("conn chain_size %i connpt_o %i num_dests %i i %i y %i x %i str %s\n",
-				break;
+				conns.chain.chain_size, conns.connpt_dest_start,
-			conn_to_str = fpga_conn_to(&model, P46_y, P46_x,
+				conns.num_dests, conns.dest_i, conns.dest_y, conns.dest_x, conns.dest_str);
-				conn_idx, &conn_to_y, &conn_to_x);
+
-			printf("  %s goes to y%02i x%02i %s\n",
+			strcpy(tmp_str, conns.dest_str);
-				tmp_str, conn_to_y, conn_to_x, conn_to_str);
+			conns2.model = &model;
-			if (is_aty(Y_TOP_INNER_IO|Y_BOT_INNER_IO, &model, conn_to_y)) {
+			conns2.y = conns.dest_y;
-				rc = printf_switchtree(&model, conn_to_y,
+			conns2.x = conns.dest_x;
-					conn_to_x, conn_to_str, /*indent*/ 3);
+			conns2.start_switch = tmp_str;
-				if (rc) FAIL(rc);
+			while (fpga_switch_conns_enum(&conns2) != NO_CONN) {
+				if (is_atyx(YX_ROUTING_TILE, &model, conns2.dest_y, conns2.dest_x)) {
+					struct swchain_conns conns3;
+
+					printf("conn2 chain_size %i connpt_o %i num_dests %i i %i y %i x %i str %s\n",
+						conns2.chain.chain_size, conns2.connpt_dest_start,
+						conns2.num_dests, conns2.dest_i, conns2.dest_y, conns2.dest_x, conns2.dest_str);
+
+#if 0
+					rc = printf_switchtree(&model, conns2.dest_y,
+						conns2.dest_x, conns2.dest_str, /*indent*/ 3);
+					if (rc) FAIL(rc);
+#endif
+
+					strcpy(tmp_str, conns2.dest_str);
+					conns3.model = &model;
+					conns3.y = conns2.dest_y;
+					conns3.x = conns2.dest_x;
+					conns3.start_switch = tmp_str;
+					while (fpga_switch_conns_enum(&conns3) != NO_CONN) {
+						printf("conn3 chain_size %i connpt_o %i num_dests %i i %i y %i x %i str %s\n",
+							conns3.chain.chain_size, conns3.connpt_dest_start,
+							conns3.num_dests, conns3.dest_i, conns3.dest_y, conns3.dest_x, conns3.dest_str);
+					}
+					break;
+				}
+			}
+			break;
+#if 0
+			rc = printf_switchtree(&model, conns.dest_y,
+				conns.dest_x, conns.dest_str, /*indent*/ 3);
+			if (rc) FAIL(rc);
 
 // go through whole tree of what is reachable from that
 // switch, look for outside connections that reach to a routing tile
-				{ swidx_t idx;
+			chain.model = &model;
-				swidx_t* parents; int num_parents;
+			chain.y = conns.dest_y;
-
+			chain.x = conns.dest_x;
-				idx = fpga_switch_tree(&model, conn_to_y, conn_to_x,
+			chain.start_switch = conns.dest_str;
-					conn_to_str, SW_FROM, &parents, &num_parents);
+			chain.from_to = SW_FROM;
-				while (idx != NO_SWITCH) {
+			while (fpga_switch_chain_enum(&chain) != NO_SWITCH) {
-					printf("idx %i num_parents %i from %s to %s\n",
+				printf("idx %i chain_size %i from %s to %s\n",
-						idx, num_parents,
+					chain.chain[chain.chain_size-1], chain.chain_size-1,
-						fpga_switch_str(&model, conn_to_y, conn_to_x, idx, SW_FROM),
+					fpga_switch_str(&model, chain.y, chain.x, chain.chain[chain.chain_size-1], SW_FROM),
-						fpga_switch_str(&model, conn_to_y, conn_to_x, idx, SW_TO));
+					fpga_switch_str(&model, chain.y, chain.x, chain.chain[chain.chain_size-1], SW_TO));
-					idx = fpga_switch_tree(&model, conn_to_y, conn_to_x,
-						SW_TREE_NEXT, SW_FROM, &parents, &num_parents);
-				}
-				}
 			}
+#endif
 		}
-		sw_idx = fpga_switch_next(&model, P46_y, P46_x, sw_idx, SW_FROM);
 	}
+
 	printf("P48 O pinw %s\n", P48_dev->iob.pinw_in_O);
 
 	printf("\n");

control.c

@@ -262,11 +262,11 @@ int fpga_set_lut(struct fpga_model* model, struct fpga_device* dev,
 	return 0;
 }
 
-int fpga_conn_dest(struct fpga_model* model, int y, int x,
+int fpga_connpt_lookup(struct fpga_model* model, int y, int x,
-	const char* name, int dest_idx)
+	const char* name, int* connpt_dests_o)
 {
 	struct fpga_tile* tile;
-	int i, rc, connpt_i, num_dests, conn_point_dests_o;
+	int i, rc, connpt_i, num_dests;
 
 	rc = strarray_find(&model->str, name, &connpt_i);
 	if (rc) FAIL(rc);
@@ -278,22 +278,20 @@ int fpga_conn_dest(struct fpga_model* model, int y, int x,
 	if (i >= tile->num_conn_point_names)
 		FAIL(EINVAL);
 
-	conn_point_dests_o = tile->conn_point_names[i*2];
+	*connpt_dests_o = tile->conn_point_names[i*2];
 	if (i < tile->num_conn_point_names-1)
-		num_dests = tile->conn_point_names[(i+1)*2] - conn_point_dests_o;
+		num_dests = tile->conn_point_names[(i+1)*2] - *connpt_dests_o;
 	else
-		num_dests = tile->num_conn_point_dests - conn_point_dests_o;
+		num_dests = tile->num_conn_point_dests - *connpt_dests_o;
-	if (dest_idx >= num_dests)
+	return num_dests;
-		return NO_CONN;
-	return conn_point_dests_o + dest_idx;
 fail:
-	return NO_CONN;
+	return 0;
 }
 
 #define NUM_CONN_DEST_BUFS	16
 #define CONN_DEST_BUF_SIZE	128
 
-const char* fpga_conn_to(struct fpga_model* model, int y, int x,
+const char* fpga_conn_dest(struct fpga_model* model, int y, int x,
 	int connpt_dest_idx, int* dest_y, int* dest_x)
 {
 	static char conn_dest_buf[NUM_CONN_DEST_BUFS][CONN_DEST_BUF_SIZE];
@@ -346,7 +344,8 @@ fail:
 	return NO_SWITCH;
 }
 
-swidx_t fpga_switch_next(struct fpga_model* model, int y, int x, swidx_t last, int from_to)
+static swidx_t fpga_switch_search(struct fpga_model* model, int y, int x,
+	swidx_t last, swidx_t search_beg, int from_to)
 {
 	struct fpga_tile* tile;
 	int connpt_o, name_i, i;
@@ -357,7 +356,7 @@ swidx_t fpga_switch_next(struct fpga_model* model, int y, int x, swidx_t last, i
 		: SWITCH_TO(tile->switches[last]);
 	name_i = tile->conn_point_names[connpt_o*2+1];
 
-	for (i = last+1; i < tile->num_switches; i++) {
+	for (i = search_beg; i < tile->num_switches; i++) {
 		connpt_o = (from_to == SW_FROM)
 			? SWITCH_FROM(tile->switches[i])
 			: SWITCH_TO(tile->switches[i]);
@@ -367,58 +366,16 @@ swidx_t fpga_switch_next(struct fpga_model* model, int y, int x, swidx_t last, i
 	return (i >= tile->num_switches) ? NO_SWITCH : i;
 }
 
-#define MAX_SW_PARENTS 32
+swidx_t fpga_switch_next(struct fpga_model* model, int y, int x,
-
+	swidx_t last, int from_to)
-swidx_t fpga_switch_tree(struct fpga_model* model, int y, int x,
-	const char* name, int from_to, swidx_t** parents, int* num_parents)
 {
-	// the static 'parents' always contain the current
+	return fpga_switch_search(model, y, x, last, last+1, from_to);
-	// (last) member as their last element, which is
+}
-	// not reported back as a parent.
-	static swidx_t s_parents[MAX_SW_PARENTS];
-	static int s_num_parents = 0;
 
-	swidx_t idx;
+swidx_t fpga_switch_backtofirst(struct fpga_model* model, int y, int x,
-
+	swidx_t last, int from_to)
-	*parents = s_parents;
+{
-	if (name != SW_TREE_NEXT) {
+	return fpga_switch_search(model, y, x, last, /*search_beg*/ 0, from_to);
-		idx = fpga_switch_first(model, y, x, name, from_to);
-		if (idx == NO_SWITCH) return NO_SWITCH;
-		s_parents[0] = idx;
-		s_num_parents = 1;
-		*num_parents = 0;
-		return idx;
-	}
-	if (!s_num_parents) {
-		HERE();
-		return NO_SWITCH;
-	}
-	// first check whether there are children
-	idx = fpga_switch_first(model, y, x,
-		fpga_switch_str(model, y, x, s_parents[s_num_parents-1], !from_to),
-		from_to);
-	if (idx != NO_SWITCH) {
-		if (s_num_parents >= MAX_SW_PARENTS) {
-			HERE();
-			return NO_SWITCH;
-		}
-		s_parents[s_num_parents] = idx;
-		s_num_parents++;
-		*num_parents = s_num_parents - 1;
-		return idx;
-	}
-	do {
-		// then check whether there are more members at the same level
-		idx = fpga_switch_next(model, y, x, s_parents[s_num_parents-1],
-			from_to);
-		if (idx != NO_SWITCH) {
-			s_parents[s_num_parents-1] = idx;
-			*num_parents = s_num_parents - 1;
-			return idx;
-		}
-		// and finally go one level up
-	} while (s_num_parents--); // post-decrement
-	return NO_SWITCH;
 }
 
 #define NUM_CONNPT_BUFS	16
@@ -476,3 +433,122 @@ void fpga_switch_disable(struct fpga_model* model, int y, int x,
 {
 	YX_TILE(model, y, x)->switches[swidx] &= ~SWITCH_ON;
 }
+
+int fpga_switch_chain_enum(struct sw_chain* chain)
+{
+	swidx_t idx;
+
+	if (chain->start_switch != SW_CHAIN_NEXT) {
+		idx = fpga_switch_first(chain->model, chain->y, chain->x,
+			chain->start_switch, chain->from_to);
+		chain->start_switch = SW_CHAIN_NEXT;
+		if (idx == NO_SWITCH) {
+			chain->chain_size = 0;
+			return NO_SWITCH;
+		}
+		chain->chain[0] = idx;
+		chain->chain_size = 1;
+
+		// at every level, the first round returns all members
+		// at that level, then the second round tries to go
+		// one level down for each member. This sorts the
+		// returned switches in a nice way.
+		chain->first_round = 1;
+		return 0;
+	}
+	if (!chain->chain_size) {
+		HERE(); goto internal_error;
+	}
+	if (chain->first_round) {
+		// first go through all members are present level
+		idx = fpga_switch_next(chain->model, chain->y, chain->x,
+			chain->chain[chain->chain_size-1], chain->from_to);
+		if (idx != NO_SWITCH) {
+			chain->chain[chain->chain_size-1] = idx;
+			return 0;
+		}
+		// if there are no more, initiate the second round
+		// looking for children
+		chain->first_round = 0;
+		idx = fpga_switch_backtofirst(chain->model, chain->y, chain->x,
+			chain->chain[chain->chain_size-1], chain->from_to);
+		if (idx == NO_SWITCH) {
+			HERE(); goto internal_error;
+		}
+		chain->chain[chain->chain_size-1] = idx;
+	}
+	// look for children
+	while (1) {
+		idx = fpga_switch_first(chain->model, chain->y, chain->x,
+			fpga_switch_str(chain->model, chain->y, chain->x,
+			chain->chain[chain->chain_size-1], !chain->from_to),
+			chain->from_to);
+		chain->chain[chain->chain_size-1] = fpga_switch_next(
+			chain->model, chain->y, chain->x,
+			chain->chain[chain->chain_size-1], chain->from_to);
+		if (idx != NO_SWITCH) {
+			if (chain->chain_size >= MAX_SW_CHAIN_SIZE) {
+				HERE(); goto internal_error;
+			}
+			chain->first_round = 1; // back to first round at new level
+			chain->chain[chain->chain_size] = idx;
+			chain->chain_size++;
+			return 0;
+		}
+		while (chain->chain[chain->chain_size-1] == NO_SWITCH) {
+			if (chain->chain_size <= 1) {
+				chain->chain_size = 0;
+				return NO_SWITCH;
+			}
+			chain->chain_size--;
+		}
+	}
+internal_error:
+	chain->chain_size = 0;
+	return NO_SWITCH;
+}
+
+int fpga_switch_conns_enum(struct swchain_conns* conns)
+{
+	const char* end_of_chain_str;
+
+	if (conns->start_switch != SW_CHAIN_NEXT) {
+		conns->chain.model = conns->model;
+		conns->chain.y = conns->y;
+		conns->chain.x = conns->x;
+		conns->chain.start_switch = conns->start_switch;
+		conns->chain.from_to = SW_FROM;
+
+		conns->start_switch = SW_CHAIN_NEXT;
+		conns->num_dests = 0;
+		conns->dest_i = 0;
+	}
+	else if (!conns->chain.chain_size) { HERE(); goto internal_error; }
+
+	while (conns->dest_i >= conns->num_dests) {
+		fpga_switch_chain_enum(&conns->chain);
+		if (conns->chain.chain_size == 0)
+			return NO_CONN;
+		end_of_chain_str = fpga_switch_str(conns->model,
+			conns->y, conns->x,
+			conns->chain.chain[conns->chain.chain_size-1],
+			SW_TO);
+		if (!end_of_chain_str) { HERE(); goto internal_error; }
+		conns->dest_i = 0;
+		conns->num_dests = fpga_connpt_lookup(conns->model,
+			conns->y, conns->x, end_of_chain_str,
+			&conns->connpt_dest_start);
+		if (conns->num_dests)
+			break;
+	}
+	conns->dest_str = fpga_conn_dest(conns->model, conns->y, conns->x,
+		conns->connpt_dest_start + conns->dest_i,
+		&conns->dest_y, &conns->dest_x);
+	if (!conns->dest_str) { HERE(); goto internal_error; }
+	conns->dest_i++;
+	return 0;
+		
+internal_error:
+	conns->chain.chain_size = 0;
+	return NO_CONN;
+}

control.h

@@ -31,10 +31,13 @@ enum { A6_LUT, B6_LUT, C6_LUT, D6_LUT };
 int fpga_set_lut(struct fpga_model* model, struct fpga_device* dev,
 	int which_lut, const char* lut_str, int lut_len);
 
-// returns a connpt dest index, or -1 (NO_CONN) if no connection was found
+// returns the number of outgoing connections for the
-int fpga_conn_dest(struct fpga_model* model, int y, int x,
+// connection point given with 'name', and the connection
-	const char* name, int dest_idx);
+// point's first dest offset in connpt_dests_o.
-const char* fpga_conn_to(struct fpga_model* model, int y, int x,
+int fpga_connpt_lookup(struct fpga_model* model, int y, int x,
+	const char* name, int* connpt_dests_o);
+
+const char* fpga_conn_dest(struct fpga_model* model, int y, int x,
 	int connpt_dest_idx, int* dest_y, int* dest_x);
 
 typedef int swidx_t;
@@ -48,11 +51,8 @@ swidx_t fpga_switch_first(struct fpga_model* model, int y, int x,
 	const char* name, int from_to);
 swidx_t fpga_switch_next(struct fpga_model* model, int y, int x,
 	swidx_t last, int from_to);
-
+swidx_t fpga_switch_backtofirst(struct fpga_model* model, int y, int x,
-#define SW_TREE_NEXT	0 // use for name
+	swidx_t last, int from_to);
-// returns -1 (NO_SWITCH) when there are no more switches in the tree
-swidx_t fpga_switch_tree(struct fpga_model* model, int y, int x,
-	const char* name, int from_to, swidx_t** parents, int* num_parents);
 
 const char* fpga_switch_str(struct fpga_model* model, int y, int x,
 	swidx_t swidx, int from_to);
@@ -64,3 +64,52 @@ void fpga_switch_enable(struct fpga_model* model, int y, int x,
 	swidx_t swidx);
 void fpga_switch_disable(struct fpga_model* model, int y, int x,
 	swidx_t swidx);
+
+#define SW_CHAIN_NEXT		0 // use for name
+#define MAX_SW_CHAIN_SIZE	32
+
+struct sw_chain
+{
+	// start and recurring values:
+	struct fpga_model* model;
+	int y;
+	int x;
+	// start_switch will be set to SW_CHAIN_NEXT (0) after the first call
+	const char* start_switch;
+	int from_to;
+
+	// return values:
+	swidx_t chain[MAX_SW_CHAIN_SIZE];
+	int chain_size;
+
+	// internal:
+	int first_round;	
+};
+
+// Returns 0 if another switch is returned in chain, or
+// NO_SWITCH (-1) if there is no other switch.
+// chain_size set to 0 when there are no more switches in the tree
+int fpga_switch_chain_enum(struct sw_chain* chain);
+
+struct swchain_conns
+{
+	// start and recurring values:
+   	struct fpga_model* model;
+	int y;
+	int x;
+	// start_switch will be set to SW_CHAIN_NEXT (0) after first call
+	const char* start_switch;
+
+	// return values:
+	struct sw_chain chain;
+	int connpt_dest_start;
+	int num_dests;
+	int dest_i;
+	int dest_y;
+	int dest_x;
+	const char* dest_str;
+};
+
+// Returns 0 if another connection is returned in conns, or
+// NO_CONN (-1) if there is no other connection.
+int fpga_switch_conns_enum(struct swchain_conns* conns);