main: draw images on framebuffer

.gitignore

@@ -12,4 +12,6 @@ __pycache__
 *.cmd
 *.order
 *.mod.c
-*.out
+*.out
+*.rgb565.inc
+main

Makefile

@@ -1,2 +1,8 @@
 %.csv: %.ods
 	libreoffice --headless --convert-to csv:"Text - txt - csv (StarCalc)":44,34,76,,,,true --outdir $(dir $@) $<
+
+%.rgb565.inc: %.rgb565
+	python gen/rgb_txt.py $< > $@
+
+main: main.c bear.rgb565.inc panda.rgb565.inc
+	gcc -g -Og -std=c23 $< -o $@

gen/rgb_txt.py

@@ -0,0 +1,9 @@
+import struct
+import sys
+
+with open(sys.argv[1], 'rb') as f:
+    buf = f.read()
+
+for i in range(len(buf) // 2):
+    value, = struct.unpack('<H', buf[i*2:i*2+2])
+    print(f"{value},")

main.c

@@ -17,7 +17,7 @@ static inline bool _wait_graphics_busy(voodoo2_reg * voodoo2)
 {
   int cnt = 0;
   for (int i = 0; i < 4096; i++) {
-    if (voodoo2->status & STATUS__GRAPHICS_BUSY) {
+    if (voodoo2->status & STATUS__CHUCK_BUSY) {
       cnt = 0;
     } else {
       cnt += 1;
@@ -183,11 +183,10 @@ int main()
   ////////////////////////////////////////////////////////////////////////
   // reset
   ////////////////////////////////////////////////////////////////////////
-
   init_enable
     = INIT_ENABLE__ENABLE_WRITES_TO_HARDWARE_REGISTERS;
   write_fd_u32(config_fd, PCI__CONFIG__INIT_ENABLE, init_enable);
-  //wait_graphics_busy(voodoo2);
+  wait_graphics_busy(voodoo2);
 
   voodoo2->fbiInit0
     = FBIINIT0__CHUCK_GRAPHICS_RESET
@@ -208,6 +207,7 @@ int main()
   // DAC initialization
   ////////////////////////////////////////////////////////////////////////
 
+  // enable fbiInit2/dacRead remap
   init_enable
     = INIT_ENABLE__ENABLE_WRITES_TO_HARDWARE_REGISTERS
     | INIT_ENABLE__REMAP_FBIINIT2_FBIINIT3_TO_DACREAD_VIDEOCHECKSUM;
@@ -243,6 +243,150 @@ int main()
   printf("dac read: DAC__PLL_PARAMETER__PLL_CONTROL: m: %02x\n",
          pll_control_res.m);
 
+  // disable fbiInit2/dacRead remap
+  init_enable
+    = INIT_ENABLE__ENABLE_WRITES_TO_HARDWARE_REGISTERS;
+  write_fd_u32(config_fd, PCI__CONFIG__INIT_ENABLE, init_enable);
+  wait_graphics_busy(voodoo2);
+
+  ////////////////////////////////////////////////////////////////////////
+  // framebuffer initialization
+  ////////////////////////////////////////////////////////////////////////
+  voodoo2->fbiInit0
+    = FBIINIT0__VGA_PASSTHROUGH // disable VGA passthrough
+    | FBIINIT0__STALL_PCI_ENABLE_FOR_HIGH_WATER_MARK
+    | FBIINIT0__PCI_FIFO_EMPTY_ENTRIES_LOW_WATER_MARK(0x10)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  int x_tiles = 832 / 32;
+  int x_tiles_0 = (x_tiles >> 0) & 0b1;
+  int x_tiles_4_1 = (x_tiles >> 1) & 0b1111;
+  int x_tiles_5 = (x_tiles >> 5) & 0b1;
+
+  voodoo2->fbiInit1
+    = FBIINIT1__ENABLE_LINEAR_FRAME_BUFFER_READS
+    | FBIINIT1__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION_4_1(x_tiles_4_1)
+    | FBIINIT1__DRIVE_VIDEO_TIMING_DATA_OUTPUTS
+    | FBIINIT1__DRIVE_VIDEO_TIMING_BLANK_OUTPUTS
+    | FBIINIT1__DRIVE_VIDEO_TIMING_HSYNC_VSYNC_OUTPUTS
+    | FBIINIT1__DRIVE_VIDEO_TIMING_DCLK_OUTPUT
+    | FBIINIT1__VIDEO_TIMING_VCLK_INPUT_SELECT(0)
+    | FBIINIT1__VIDEO_TIMING_VCLK_SOURCE_SELECT__VID_CLK_2X_SEL
+    | FBIINIT1__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION_5(x_tiles_5)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->fbiInit2
+    = FBIINIT2__DRAM_BANKING_CONFIGURATION
+    | FBIINIT2__ENABLE_FAST_RAS_READ_CYCLES
+    | FBIINIT2__ENABLE_GENERATED_DRAM_OE_SIGNAL
+    | FBIINIT2__VIDEO_BUFFER_OFFSET(247)
+    | FBIINIT2__ENABLE_DRAM_READ_AHEAD_FIFO
+    | FBIINIT2__REFRESH_ENABLE
+    | FBIINIT2__REFRESH_LOAD_VALUE(0x30)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->fbiInit3
+    = FBIINIT3__DISABLE_TEXTURE_MAPPING
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->fbiInit4
+    = FBIINIT4__ENABLE_READ_AHEAD_LOGIC_FOR_LINEAR_FRAME_BUFFER_READS
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->fbiInit5
+    = FBIINIT5__INVERT_DAC_HSYNC_OUTPUT_TO_DAC
+    | FBIINIT5__INVERT_DAC_VSYNC_OUTPUT_TO_DAC
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->fbiInit6
+    = FBIINIT6__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION_0(x_tiles_0)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  ////////////////////////////////////////////////////////////////////////
+  // video timing initialization
+  ////////////////////////////////////////////////////////////////////////
+
+  int y_height = 600;
+  int x_width = 800;
+
+  int v_back_porch = 628 - 605;
+  int h_back_porch = 1056 - 968;
+
+  int v_sync_on = 605 - 601;
+  int h_sync_on = 968 - 840;
+
+  int v_sync_off = 628 - v_sync_on;
+  int h_sync_off = 1056 - h_sync_on;
+
+  voodoo2->hSync
+    = HSYNC__H_SYNC_ON(h_sync_on - 1)
+    | HSYNC__H_SYNC_OFF(h_sync_off)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->vSync
+    = VSYNC__V_SYNC_ON(v_sync_on)
+    | VSYNC__V_SYNC_OFF(v_sync_off)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->backPorch
+    = BACKPORCH__H_BACK_PORCH(h_back_porch - 2)
+    | BACKPORCH__V_BACK_PORCH(v_back_porch)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  voodoo2->videoDimensions
+    = VIDEODIMENSIONS__X_WIDTH(x_width - 1)
+    | VIDEODIMENSIONS__Y_HEIGHT(y_height)
+    ;
+  wait_graphics_busy(voodoo2);
+
+  ////////////////////////////////////////////////////////////////////////
+  // panda
+  ////////////////////////////////////////////////////////////////////////
+
+  init_enable
+    = INIT_ENABLE__ENABLE_WRITES_TO_PCI_FIFO;
+  write_fd_u32(config_fd, PCI__CONFIG__INIT_ENABLE, init_enable);
+  wait_graphics_busy(voodoo2);
+
+  static const uint16_t panda[] __attribute__((aligned(4))) = {
+    #include "panda.rgb565.inc"
+  };
+  static const uint16_t bear[] __attribute__((aligned(4))) = {
+    #include "bear.rgb565.inc"
+  };
+
+  while (true) {
+    volatile uint16_t * framebuffer
+      = (volatile uint16_t * )(((ptrdiff_t)resource0_base) + 0x0400000);
+
+    printf("panda\n");
+    for (int y = 0; y < 600; y++) {
+      for (int x = 0; x < 800; x++) {
+        framebuffer[y * 1024 + x] = panda[y * 800 + x];
+        wait_graphics_busy(voodoo2);
+      }
+    }
+    sleep(1);
+    printf("bear\n");
+    for (int y = 0; y < 600; y++) {
+      for (int x = 0; x < 800; x++) {
+        framebuffer[y * 1024 + x] = bear[y * 800 + x];
+        wait_graphics_busy(voodoo2);
+      }
+    }
+    sleep(1);
+  }
+
   ////////////////////////////////////////////////////////////////////////
   // cleanup
   ////////////////////////////////////////////////////////////////////////

voodoo2_bits.h

@@ -233,6 +233,9 @@
 #define VIDEODIMENSIONS__X_WIDTH(n) (((n) & 0x7ff) << 0)
 #define VIDEODIMENSIONS__Y_HEIGHT(n) (((n) & 0x7ff) << 16)
 
+#define BACKPORCH__H_BACK_PORCH(n) (((n) & 0x1ff) << 0)
+#define BACKPORCH__V_BACK_PORCH(n) (((n) & 0x1ff) << 16)
+
 #define MAXRGBDELTA__BLUE(n) (((n) & 0xff) << 0)
 #define MAXRGBDELTA__GREEN(n) (((n) & 0xff) << 8)
 #define MAXRGBDELTA__RED(n) (((n) & 0xff) << 16)
@@ -262,7 +265,7 @@
 #define FBIINIT1__PCI_DEVICE_FUNCTION_NUMBER (1 << 0)
 #define FBIINIT1__WAIT_STATE_CYCLES_FOR_PCI_WRITE_ACCESSES (1 << 1)
 #define FBIINIT1__ENABLE_LINEAR_FRAME_BUFFER_READS (1 << 3)
-#define FBIINIT1__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION(n) (((n) & 0xf) << 4)
+#define FBIINIT1__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION_4_1(n) (((n) & 0xf) << 4)
 #define FBIINIT1__VIDEO_TIMING_RESET (1 << 8)
 #define FBIINIT1__SOFTWARE_OVERRIDE_OF_HSYNC_VSYNC (1 << 9)
 #define FBIINIT1__SOFTWARE_OVERRIDE_HSYNC_VALUE (1 << 10)
@@ -272,7 +275,7 @@
 #define FBIINIT1__DRIVE_VIDEO_TIMING_BLANK_OUTPUTS (1 << 14)
 #define FBIINIT1__DRIVE_VIDEO_TIMING_HSYNC_VSYNC_OUTPUTS (1 << 15)
 #define FBIINIT1__DRIVE_VIDEO_TIMING_DCLK_OUTPUT (1 << 16)
-#define FBIINIT1__VIDEO_TIMING_VCLK_INPUT_SELECT (1 << 17)
+#define FBIINIT1__VIDEO_TIMING_VCLK_INPUT_SELECT(n) (((n) & 1) << 17)
 #define FBIINIT1__VID_CLK_2X_DELAY_SELECT__NO_DELAY (0 << 18)
 #define FBIINIT1__VID_CLK_2X_DELAY_SELECT__4NS (1 << 18)
 #define FBIINIT1__VID_CLK_2X_DELAY_SELECT__6NS (2 << 18)
@@ -282,7 +285,7 @@
 #define FBIINIT1__VIDEO_TIMING_VCLK_SOURCE_SELECT__VID_CLK_2X_SEL (2 << 20)
 #define FBIINIT1__ENABLE_24_BITS_PER_PIXEL_VIDEO_OUTPUT (1 << 22)
 #define FBIINIT1__ENABLE_SCAN_LINE_INTERLEAVING (1 << 23)
-#define FBIINIT1__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION_5 (1 << 24)
+#define FBIINIT1__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION_5(n) (((n) & 1) << 24)
 #define FBIINIT1__ENABLE_VIDEO_EDGE_DETECTION_FILTERING (1 << 25)
 #define FBIINIT1__INVERT_VID_CLK_2X (1 << 26)
 #define FBIINIT1__VID_CLK_2X_SEL_DELAY_SELECT__NO_DELAY (0 << 27)
@@ -368,7 +371,7 @@
 #define FBIINIT6__DAC_WR_OUTPUT_VALUE(n) (((n) & 0x3) << 19)
 #define FBIINIT6__PCI_FIFO_EMPTY_ENTRIES_LOW_WATER_MARK(n) (((n) & 0x7f) << 21)
 #define FBIINIT6__VGA_PASS_N_OUTPUT_VALUE(n) (((n) & 0x3) << 28)
-#define FBIINIT6__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION (1 << 30)
+#define FBIINIT6__NUMBER_OF_32X32_VIDEO_TILES_IN_HORIZONTAL_DIMENSION_0(n) (((n) & 1) << 30)
 
 #define FBIINIT7__CMDFIFO_ENABLE (1 << 8)
 #define FBIINIT7__CMDFIFO_OFFSCREEN_MEMORY_STORE (1 << 9)