buid/sim: add vga framebuffer with SDL

litex/boards/platforms/sim.py

@@ -30,6 +30,14 @@ _io = [
         Subsignal("sink_ready", SimPins(1)),
         Subsignal("sink_data", SimPins(8)),
     ),
+    ("vga", 0,
+        Subsignal("de", SimPins(1)),
+        Subsignal("hsync", SimPins(1)),
+        Subsignal("vsync", SimPins(1)),
+        Subsignal("r", SimPins(8)),
+        Subsignal("g", SimPins(8)),
+        Subsignal("b", SimPins(8)),
+    ),
 ]
 
 

litex/build/sim/dut_tb.cpp

@@ -17,6 +17,8 @@
 #include <linux/if.h>
 #include <linux/if_tun.h>
 
+#include <SDL/SDL.h>
+
 /* ios */
 
 #ifdef SERIAL_SOURCE_VALID
@@ -27,6 +29,10 @@
 #define WITH_ETH
 #endif
 
+#ifdef VGA_DE
+#define WITH_VGA
+#endif
+
 #define MAX(a,b) (((a)>(b))?(a):(b))
 #define MIN(a,b) (((a)<(b))?(a):(b))
 
@@ -38,6 +44,9 @@ double sc_time_stamp()
 	return main_time;
 }
 
+Vdut* dut;
+VerilatedVcdC* tfp;
+
 /* Sim struct */
 struct sim {
 	bool run;
@@ -180,8 +189,78 @@ int eth_read(struct sim *s, unsigned char *buf)
 }
 #endif
 
-Vdut* dut;
-VerilatedVcdC* tfp;
+/* VGA functions */
+#ifdef WITH_VGA
+
+SDL_Surface *screen;
+SDL_Event event;
+
+void vga_set_pixel(SDL_Surface *screen, int x, int y, char r, char g, char b)
+{
+	unsigned int *pixmem32;
+	unsigned int color;
+
+	color = SDL_MapRGB(screen->format, r, g, b);
+	pixmem32 = (unsigned int*) screen->pixels  + y*640 + x;
+	*pixmem32 = color;
+}
+
+int vga_init(struct sim *s) {
+	if(SDL_Init(SDL_INIT_VIDEO) < 0) return 1;
+	if(!(screen = SDL_SetVideoMode(640, 480, 32, SDL_HWSURFACE))) {
+		SDL_Quit();
+		return 1;
+	}
+	return 0;
+}
+
+int x;
+int y;
+int hsync_needs_de = 1;
+int vsync_needs_de = 1;
+
+void vga_service(struct sim *s) {
+	if(VGA_HSYNC == 1 && hsync_needs_de == 0) {
+		x = 0;
+		y++;
+		hsync_needs_de = 1;
+	}
+	if(VGA_VSYNC == 1 && vsync_needs_de == 0) {
+		y = 0;
+		vsync_needs_de = 1;
+		if(SDL_MUSTLOCK(screen))
+			SDL_UnlockSurface(screen);
+		SDL_Flip(screen);
+		if(SDL_MUSTLOCK(screen))
+			SDL_LockSurface(screen);
+	}
+	if(VGA_DE == 1) {
+		hsync_needs_de = 0;
+		vsync_needs_de = 0;
+		vga_set_pixel(screen, x, y, VGA_R, VGA_G, VGA_B);
+		x++;
+	}
+
+	if(s->tick%1000 == 0) {
+		while(SDL_PollEvent(&event)) {
+			switch (event.type) {
+				case SDL_QUIT:
+					s->run = false;
+					break;
+				case SDL_KEYDOWN:
+					s->run = false;
+					break;
+			}
+		}
+	}
+}
+
+int vga_close(struct sim *s) {
+	SDL_Quit();
+}
+
+#endif
+
 
 #ifndef WITH_SERIAL_PTY
 int console_service(struct sim *s)
@@ -366,6 +445,10 @@ int main(int argc, char **argv, char **env)
 	eth_open(&s);
 #endif
 
+#ifdef WITH_VGA
+	if(vga_init(&s)) return 1;
+#endif
+
 	s.run = true;
 	while(s.run) {
 		sim_tick(&s);
@@ -376,6 +459,9 @@ int main(int argc, char **argv, char **env)
 #endif
 #ifdef WITH_ETH
 			ethernet_service(&s);
+#endif
+#ifdef WITH_VGA
+			vga_service(&s);
 #endif
 		}
 	}
@@ -387,13 +473,15 @@ int main(int argc, char **argv, char **env)
 
 	tfp->close();
 
-
 #ifdef WITH_SERIAL_PTY
 	console_close(&s);
 #endif
 #ifdef WITH_ETH
 	eth_close(&s);
 #endif
+#ifdef WITH_VGA
+	vga_close(&s);
+#endif
 
 	exit(0);
 }

litex/build/sim/verilator.py

@@ -1,4 +1,4 @@
-# This file is Copyright (c) 2015 Florent Kermarrec <florent@enjoy-digital.fr>
+# This file is Copyright (c) 2015-2016 Florent Kermarrec <florent@enjoy-digital.fr>
 # License: BSD
 
 import os
@@ -71,6 +71,25 @@ def _build_tb(platform, vns, serial, template):
     except:
         pass
 
+    try:
+        ios += """
+#define VGA_DE dut->{vga_de}
+#define VGA_HSYNC dut->{vga_hsync}
+#define VGA_VSYNC dut->{vga_vsync}
+#define VGA_R dut->{vga_r}
+#define VGA_G dut->{vga_g}
+#define VGA_B dut->{vga_b}
+""".format(
+    vga_de=io_name("vga", "de"),
+    vga_hsync=io_name("vga", "hsync"),
+    vga_vsync=io_name("vga", "vsync"),
+    vga_r=io_name("vga", "r"),
+    vga_g=io_name("vga", "g"),
+    vga_b=io_name("vga", "b"),
+    )
+    except:
+        pass
+
     content = ""
     f = open(template, "r")
     done = False
@@ -91,7 +110,7 @@ def _build_sim(platform, vns, build_name, include_paths, serial, verbose):
 
     build_script_contents = """# Autogenerated by LiteX
     rm -rf obj_dir/
-verilator {disable_warnings} -O3 --cc dut.v --exe dut_tb.cpp -LDFLAGS "-lpthread" -trace {include}
+verilator {disable_warnings} -O3 --cc dut.v --exe dut_tb.cpp -LDFLAGS "-lpthread -lSDL" -trace {include}
 make -j -C obj_dir/ -f Vdut.mk Vdut
 
 """.format(
@@ -126,7 +145,7 @@ def _run_sim(build_name):
 
 class SimVerilatorToolchain:
     def build(self, platform, fragment, build_dir="build", build_name="top",
-            toolchain_path=None, serial="console", run=True, verbose=False):
+            toolchain_path=None, serial="console", run=True, verbose=True):
         tools.mkdir_noerror(build_dir)
         os.chdir(build_dir)