build/sim: add jtagremote module (thanks LamdaConcept)

litex/build/sim/core/modules/jtagremote/Makefile

@@ -0,0 +1,5 @@
+include ../variables.mak
+
+all: $(OBJ_DIR)/jtagremote.so
+
+include ../rules.mak

litex/build/sim/core/modules/jtagremote/jtagremote.c

@@ -0,0 +1,263 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "error.h"
+#include <unistd.h>
+#include <event2/listener.h>
+#include <event2/util.h>
+#include <event2/event.h>
+
+#include <json-c/json.h>
+#include "modules.h"
+
+struct session_s {
+	char *tdi;
+	char *tdo;
+	char *tck;
+	char *tms;
+	char *sys_clk;
+	struct event *ev;
+	char databuf[2048];
+	int data_start;
+	int datalen;
+	int cntticks;
+	int fd;
+};
+
+struct event_base *base;
+
+int litex_sim_module_get_args( char *args, char *arg, char **val)
+{
+  int ret = RC_OK;
+  json_object *jsobj = NULL;
+  json_object *obj = NULL;
+  char *value = NULL;
+  int r;
+
+  jsobj = json_tokener_parse(args);
+  if(NULL==jsobj) {
+    fprintf(stderr, "Error parsing json arg: %s \n", args);
+    ret=RC_JSERROR;
+    goto out;
+  }
+  if(!json_object_is_type(jsobj, json_type_object)) {
+    fprintf(stderr, "Arg must be type object! : %s \n", args);
+    ret=RC_JSERROR;
+    goto out;
+  }
+  obj=NULL;
+  r = json_object_object_get_ex(jsobj, arg, &obj);
+  if(!r) {
+    fprintf(stderr, "Could not find object: \"%s\" (%s)\n", arg, args);
+    ret=RC_JSERROR;
+    goto out;
+  }
+  value=strdup(json_object_get_string(obj));
+
+out:
+  *val = value;
+  return ret;
+}
+
+static int litex_sim_module_pads_get( struct pad_s *pads, char *name, void **signal)
+{
+  int ret;
+  void *sig = NULL;
+  int i;
+
+  if(!pads || !name || !signal) {
+    ret = RC_INVARG;
+    goto out;
+  }
+
+  i = 0;
+  while(pads[i].name) {
+    if(!strcmp(pads[i].name, name)) {
+      sig = (void*)pads[i].signal;
+      break;
+    }
+    i++;
+  }
+
+out:
+  *signal = sig;
+  return ret;
+}
+
+static int jtagremote_start(void *b)
+{
+  base = (struct event_base *)b;
+  printf("[jtagremote] loaded (%p)\n", base);
+  return RC_OK;
+}
+
+void read_handler(int fd, short event, void *arg)
+{
+  struct session_s *s = (struct session_s*)arg;
+  char buffer[1024];
+  ssize_t read_len;
+
+  int i;
+
+  read_len = read(fd, buffer, 1024);
+  for(i = 0; i < read_len; i++)
+  {
+    s->databuf[(s->data_start +  s->datalen ) % 2048] = buffer[i];
+    s->datalen++;
+  }
+}
+
+static void event_handler(int fd, short event, void *arg)
+{
+  if (event & EV_READ)
+    read_handler(fd, event, arg);
+}
+
+static void accept_conn_cb(struct evconnlistener *listener, evutil_socket_t fd, struct sockaddr *address, int socklen,  void *ctx)
+{
+  struct session_s *s = (struct session_s*)ctx;
+  struct timeval tv = {1, 0};
+
+  s->fd = fd;
+  s->ev = event_new(base, fd, EV_READ | EV_PERSIST , event_handler, s);
+  event_add(s->ev, &tv);
+}
+
+static void
+accept_error_cb(struct evconnlistener *listener, void *ctx)
+{
+  struct event_base *base = evconnlistener_get_base(listener);
+  eprintf("ERRROR\n");
+
+  event_base_loopexit(base, NULL);
+}
+
+static int jtagremote_new(void **sess, char *args)
+{
+  int ret = RC_OK;
+  struct session_s *s = NULL;
+  char *cport = NULL;
+  int port;
+  struct evconnlistener *listener;
+  struct sockaddr_in sin;
+
+  if(!sess) {
+    ret = RC_INVARG;
+    goto out;
+  }
+
+  ret = litex_sim_module_get_args(args, "port", &cport);
+  if(RC_OK != ret)
+    goto out;
+
+  printf("Found port %s\n", cport);
+  sscanf(cport, "%d", &port);
+  free(cport);
+  if(!port) {
+    ret = RC_ERROR;
+    fprintf(stderr, "Invalid port selected!\n");
+    goto out;
+  }
+
+  s=(struct session_s*)malloc(sizeof(struct session_s));
+  if(!s) {
+    ret = RC_NOENMEM;
+    goto out;
+  }
+  memset(s, 0, sizeof(struct session_s));
+
+  memset(&sin, 0, sizeof(sin));
+  sin.sin_family = AF_INET;
+  sin.sin_addr.s_addr = htonl(0);
+  sin.sin_port = htons(port);
+  listener = evconnlistener_new_bind(base, accept_conn_cb, s,  LEV_OPT_CLOSE_ON_FREE|LEV_OPT_REUSEABLE, -1, (struct sockaddr*)&sin, sizeof(sin));
+  if (!listener) {
+    ret=RC_ERROR;
+    eprintf("Can't bind port %d\n!\n", port);
+    goto out;
+  }
+  evconnlistener_set_error_cb(listener, accept_error_cb);
+
+out:
+  *sess=(void*)s;
+  return ret;
+}
+
+static int jtagremote_add_pads(void *sess, struct pad_list_s *plist)
+{
+  int ret=RC_OK;
+  struct session_s *s=(struct session_s*)sess;
+  struct pad_s *pads;
+  if(!sess || !plist) {
+    ret = RC_INVARG;
+    goto out;
+  }
+  pads = plist->pads;
+  printf("plist name: %s\n", plist->name);
+  if(!strcmp(plist->name, "jtag")) {
+    litex_sim_module_pads_get(pads, "tck", (void**)&s->tck);
+    litex_sim_module_pads_get(pads, "tdi", (void**)&s->tdi);
+    litex_sim_module_pads_get(pads, "tdo", (void**)&s->tdo);
+    litex_sim_module_pads_get(pads, "tms", (void**)&s->tms);
+  }
+
+  if(!strcmp(plist->name, "sys_clk"))
+    litex_sim_module_pads_get(pads, "sys_clk", (void**)&s->sys_clk);
+
+out:
+  return ret;
+
+}
+static int jtagremote_tick(void *sess)
+{
+	char c, val;
+	int ret = RC_OK;
+
+  struct session_s *s = (struct session_s*)sess;
+  if(*s->sys_clk == 0)
+    return RC_OK;
+
+  s->cntticks++;
+  if(s->cntticks % 10)
+	  return RC_OK;
+
+  if(s->datalen)
+  {
+	  c = s->databuf[s->data_start];
+
+	  if((c >= '0') && (c <= '7')){
+		  *s->tck = ((c - '0') >> 2) & 1;
+		  *s->tms = ((c - '0') >> 1) & 1;
+		  *s->tdi = (c - '0')  & 1;
+	  }
+	  if(c == 'R'){
+		  val = *s->tdo + '0';
+		  if(-1 == write(s->fd, &val, 1)) {
+			  eprintf("Error writing on socket\n");
+			  ret = RC_ERROR;
+			  goto out;
+		  }
+	  }
+	  s->data_start = (s->data_start + 1) % 2048;
+	  s->datalen--;
+  }
+
+out:
+  return ret;
+}
+
+static struct ext_module_s ext_mod = {
+  "jtagremote",
+  jtagremote_start,
+  jtagremote_new,
+  jtagremote_add_pads,
+  NULL,
+  jtagremote_tick
+};
+
+int litex_sim_ext_module_init(int (*register_module)(struct ext_module_s *))
+{
+  int ret = RC_OK;
+  ret = register_module(&ext_mod);
+  return ret;
+}