From cab072d239d772d1c3445612d2599da36b087b25 Mon Sep 17 00:00:00 2001
From: John Tsiombikas <nuclear@member.fsf.org>
Date: Wed, 25 Jul 2018 19:44:52 +0300
Subject: [PATCH] testing stuff

---
 Makefile.amiga            |   17 ++++++++-
 src/amiga/copper.c        |   77 ++++++++++++++++++++++++++++++++++++++
 src/amiga/copper.h        |   39 ++++++++++++++++++++
 src/amiga/gfx.c           |   26 +++++++++++++
 src/amiga/gfx.h           |   25 +++++++++++++
 src/amiga/libc/libc_asm.s |   24 ++++++++++++
 src/amiga/libc/stdlib.h   |    6 +++
 src/amiga/libc/string.h   |    9 +++++
 src/amiga/main.c          |   45 ++++++++++++++++++-----
 src/data_test.h           |   38 +++++++++++++++++++
 src/game.c                |   90 +++++++++++++++++++++++++++++++++++++++++++++
 src/game.h                |    7 ++++
 12 files changed, 392 insertions(+), 11 deletions(-)
 create mode 100644 src/amiga/copper.c
 create mode 100644 src/amiga/copper.h
 create mode 100644 src/amiga/gfx.c
 create mode 100644 src/amiga/gfx.h
 create mode 100644 src/amiga/libc/libc_asm.s
 create mode 100644 src/amiga/libc/stdlib.h
 create mode 100644 src/amiga/libc/string.h
 create mode 100644 src/data_test.h
 create mode 100644 src/game.c
 create mode 100644 src/game.h

diff --git a/Makefile.amiga b/Makefile.amiga
index 38fe12d..89a02c3 100644
--- a/Makefile.amiga
+++ b/Makefile.amiga
@@ -1,7 +1,9 @@
 src = $(wildcard src/*.c) \
 	  $(wildcard src/amiga/*.c)
-asrc = $(wildcard src/amiga/*.s)
+asrc = $(wildcard src/amiga/*.s) \
+	   $(wildcard src/amiga/libc/*.s)
 obj = $(src:.c=.o) $(asrc:.s=.o) 
+dep = $(src:.c=.d)
 
 name = retrocrawl
 elf = $(name).elf
@@ -16,8 +18,10 @@ AS = $(tool_prefix)as
 LD = $(tool_prefix)ld
 OBJCOPY = $(tool_prefix)objcopy
 
+inc = -Isrc -Isrc/amiga -Isrc/amiga/libc
+
 ASFLAGS = -m68000
-CFLAGS = -m68000 -ffreestanding -pedantic -Wall -Os
+CFLAGS = -m68000 -ffreestanding -pedantic -Wall -Os $(inc)
 LDFLAGS = -T amiga.ld -print-gc-sections \
 		  -L/usr/lib/gcc-cross/m68k-linux-gnu/6 -lgcc
 
@@ -33,10 +37,19 @@ $(elf): $(obj)
 $(bootblock): src/amiga/boot/boot.o
 	$(OBJCOPY) -O binary $< $@
 
+-include $(dep)
+
+%.d: %.c
+	@$(CPP) $(CFLAGS) $< -MM -MT $(@:.d=.o) >$@
+
 .PHONY: clean
 clean:
 	rm -f $(obj) src/amiga/boot/boot.o $(bin) $(elf)
 
+.PHONY: cleandep
+cleandep:
+	rm -f $(dep)
+
 .PHONY: run
 run:
 	fs-uae
diff --git a/src/amiga/copper.c b/src/amiga/copper.c
new file mode 100644
index 0000000..2c22d8a
--- /dev/null
+++ b/src/amiga/copper.c
@@ -0,0 +1,77 @@
+#include "copper.h"
+#include "hwregs.h"
+
+uint32_t *copperlist, *copperlist_end;
+static uint32_t *copmem, *curlist;
+static int mode, copmem_size;
+
+extern uint32_t **_mem_start;
+
+int init_copper(int maxlist, int nlists)
+{
+	/* allocate and set new copper lists */
+	if(maxlist <= 0) maxlist = 256;
+	mode = nlists >= COPPER_DOUBLE ? COPPER_DOUBLE : COPPER_SINGLE;
+
+	copmem_size = maxlist * 4 * mode;
+	copmem = *_mem_start;
+
+	curlist = copperlist = copmem;
+	*curlist = COPPER_END;
+
+	if(mode == COPPER_DOUBLE) {
+		copperlist = curlist + maxlist;
+		*copperlist = COPPER_END;
+	}
+	copperlist_end = copperlist;
+
+	REG32_COP1LC = (uint32_t)curlist;
+	REG_COPJMP1 = 0;	/* causes copper to read COP1LC */
+	return 0;
+}
+
+void cleanup_copper(void)
+{
+}
+
+void enable_copper(void)
+{
+	REG_DMACON = SETBITS(DMA_COPPER);
+}
+
+void disable_copper(void)
+{
+	REG_DMACON = CLRBITS(DMA_COPPER);
+}
+
+void clear_copper(void)
+{
+	copperlist_end = copperlist;
+	*copperlist_end = COPPER_END;
+}
+
+void add_copper(uint32_t cmd)
+{
+	*copperlist_end++ = cmd;
+}
+
+void sort_copper(void)
+{
+	/* TODO */
+}
+
+void swap_copper(void)
+{
+	if(mode == COPPER_DOUBLE) {
+		uint32_t *tmpptr;
+		tmpptr = curlist;
+		curlist = copperlist;
+		copperlist = copperlist_end = tmpptr;
+
+		REG32_COP1LC = (uint32_t)curlist;
+		REG_COPJMP1 = 0;
+	} else {
+		copperlist_end = curlist;
+	}
+	*copperlist_end = COPPER_END;
+}
diff --git a/src/amiga/copper.h b/src/amiga/copper.h
new file mode 100644
index 0000000..3e64315
--- /dev/null
+++ b/src/amiga/copper.h
@@ -0,0 +1,39 @@
+#ifndef COPPER_H_
+#define COPPER_H_
+
+#include "inttypes.h"
+
+#define COPPER_MOVE(reg, data)	(((uint32_t)(reg) << 16) | ((uint32_t)(data) & 0xffff))
+#define COPPER_WAIT(x, y) \
+	(0x0001fffe | ((uint32_t)((x) + 0x81) << 16) | ((uint32_t)((y) + 0x2c) << 24))
+#define COPPER_WAIT_OVERSCAN(x, y) \
+	(0x0001fffe | ((uint32_t)(x) << 16) | ((uint32_t)(y) << 24))
+#define COPPER_VWAIT(s)			(0x0001ff00 | ((uint32_t)((s) + 0x2c) << 24))
+#define COPPER_VWAIT_OVERSCAN(s) \
+	(0x0001ff00 | ((uint32_t)(s) << 24))
+#define COPPER_OVERFLOW			0xffdffffe
+#define COPPER_END				0xfffffffe
+
+extern uint32_t *copperlist, *copperlist_end;
+
+enum {
+	COPPER_SINGLE = 1,
+	COPPER_DOUBLE = 2
+};
+
+int init_copper(int maxlist, int nlists);
+void cleanup_copper(void);
+
+/* enables copper DMA */
+void enable_copper(void);
+/* disables copper DMA */
+void disable_copper(void);
+
+void clear_copper(void);
+void add_copper(uint32_t cmd);
+void sort_copper(void);	/* TODO */
+
+void swap_copper(void);
+
+
+#endif	/* COPPER_H_ */
diff --git a/src/amiga/gfx.c b/src/amiga/gfx.c
new file mode 100644
index 0000000..b18e027
--- /dev/null
+++ b/src/amiga/gfx.c
@@ -0,0 +1,26 @@
+#include "gfx.h"
+#include "hwregs.h"
+
+int init_gfx(void)
+{
+	int i;
+
+	REG_BPLCON0 = BPLCON0_COUNT(NBPL) | BPLCON0_COLOR;
+	REG_BPLCON1 = 0;
+	REG_DIWSTART = 0x2c81;
+	REG_DIWSTOP = 0x2cc1;
+	REG_DDFSTART = 0x38;
+	REG_DDFSTOP = 0xd0;
+
+	for(i=0; i<NBPL; i++) {
+		bplptr[i] = framebuf + SCANSZ * i;
+	}
+	REG_BPL1MOD = SCANSZ * (NBPL - 1);
+	REG_BPL2MOD = SCANSZ * (NBPL - 1);
+
+	for(i=0; i<32; i++) {
+		REG_COLOR_PTR[i] = 0xf0f;
+	}
+
+	return 0;
+}
diff --git a/src/amiga/gfx.h b/src/amiga/gfx.h
new file mode 100644
index 0000000..f3352fd
--- /dev/null
+++ b/src/amiga/gfx.h
@@ -0,0 +1,25 @@
+#ifndef GFX_H_
+#define GFX_H_
+
+#define SCR_W	320
+#define SCR_H	256
+#define SCANSZ	(SCR_W / 8)
+#define BPLSZ	(SCANSZ * SCR_H)
+#define NBPL	5
+
+#define wait_vpos(x) \
+	asm volatile ( \
+		"0: move.l 0xdff004, %%d0\n\t" \
+		"and.l #0x1ff00, %%d0\n\t" \
+		"cmp.l %0, %%d0\n\t" \
+		"bne 0b\n\t" \
+		:: "i"((x) << 8) : "%d0")
+
+#define wait_vblank() wait_vpos(300)
+
+unsigned char framebuf[BPLSZ * NBPL];
+unsigned char *bplptr[NBPL];
+
+int init_gfx(void);
+
+#endif	/* GFX_H_ */
diff --git a/src/amiga/libc/libc_asm.s b/src/amiga/libc/libc_asm.s
new file mode 100644
index 0000000..095c8df
--- /dev/null
+++ b/src/amiga/libc/libc_asm.s
@@ -0,0 +1,24 @@
+| vi:filetype=gas68k:
+	.text
+
+	| optimize: transfer words at a time
+	.global memcpy
+memcpy:
+	move.l 4(%sp), %a0
+	move.l 8(%sp), %a1
+	move.l 12(%sp), %d0
+	sub.l #1, %d0
+0:	move.b (%a1)+, (%a0)+
+	dbra %d0, 0b
+	rts
+
+	| optimize: same as above
+	.global memset
+memset:
+	move.l 4(%sp), %a0
+	move.l 8(%sp), %d1
+	move.l 12(%sp), %d0
+	sub.l #1, %d0
+0:	move.b %d1, (%a0)+
+	dbra %d0, 0b
+	rts
diff --git a/src/amiga/libc/stdlib.h b/src/amiga/libc/stdlib.h
new file mode 100644
index 0000000..e0a11dc
--- /dev/null
+++ b/src/amiga/libc/stdlib.h
@@ -0,0 +1,6 @@
+#ifndef AMIGA_LIBC_STDLIB_H_
+#define AMIGA_LIBC_STDLIB_H_
+
+typedef long size_t;
+
+#endif	/* AMIGA_LIBC_STDLIB_H_ */
diff --git a/src/amiga/libc/string.h b/src/amiga/libc/string.h
new file mode 100644
index 0000000..a2e4c74
--- /dev/null
+++ b/src/amiga/libc/string.h
@@ -0,0 +1,9 @@
+#ifndef AMIGA_LIBC_STRING_H_
+#define AMIGA_LIBC_STRING_H_
+
+#include <stdlib.h>
+
+void memcpy(void *dest, const void *src, size_t n);
+void memset(void *dest, int c, size_t n);
+
+#endif	/* AMIGA_LIBC_STRING_H_ */
diff --git a/src/amiga/main.c b/src/amiga/main.c
index e3cfcd5..83d86d9 100644
--- a/src/amiga/main.c
+++ b/src/amiga/main.c
@@ -1,19 +1,46 @@
+#include <string.h>
 #include "hwregs.h"
+#include "copper.h"
+#include "gfx.h"
+#include "game.h"
+
+static uint32_t coplist[32];
 
 int main(void)
 {
-	REG_INTENA = SETBITS(INTEN_VERTB | INTEN_MASTER);
+	int i;
 
+	REG_INTENA = SETBITS(INTEN_VERTB | INTEN_MASTER);
 	REG_DMACON = CLRBITS(DMA_ALL);
-	REG_BPLCON0 = BPLCON0_COLOR;
-	REG_BPLCON1 = 0;
-	REG_DIWSTART = 0x2c81;
-	REG_DIWSTOP = 0x2cc1;
-	REG_DDFSTART = 0x38;
-	REG_DDFSTOP = 0xd0;
 
-	REG_COLOR0 = 0x237;
+	init_gfx();
+
+	REG_COLOR0 = 0x111;
+	REG_COLOR1 = 0x23c;
+	REG_COLOR2 = 0xc32;
+	REG_COLOR3 = 0x22c;
+	REG_COLOR4 = 0xcc2;
+
+	wait_vblank();
+
+	uint32_t *copptr = coplist;
+	for(i=0; i<NBPL; i++) {
+		uint32_t addr = (intptr_t)bplptr[i];
+		int reg = REGN_BPL1PTH + i * 4;
+		*copptr++ = COPPER_MOVE(reg, addr >> 16);
+		*copptr++ = COPPER_MOVE(reg + 2, addr);
+	}
+	*copptr = COPPER_END;
+	REG32_COP1LC = (uint32_t)coplist;
+	REG_COPJMP1 = 0;
+
+	REG_DMACON = SETBITS(DMA_BPL | DMA_COPPER | DMA_MASTER);
+
+	game_init();
 
-	for(;;);
+	for(;;) {
+		wait_vblank();
+		game_draw();
+	}
 	return 0;
 }
diff --git a/src/data_test.h b/src/data_test.h
new file mode 100644
index 0000000..a00cb47
--- /dev/null
+++ b/src/data_test.h
@@ -0,0 +1,38 @@
+const char test_tiles_cpix[][16][32] = {
+	{
+		"...............#x...............",
+		".............###xxx.............",
+		"...........x####xxxx#...........",
+		".........xxx####xxxx###.........",
+		".......x####xxxx####xxxx#.......",
+		".....xxx####xxxx####xxxx###.....",
+		"...#xxxx####xxxx####xxxx####x...",
+		".###xxxx####xxxx####xxxx####xxx.",
+		".xxx####xxxx####xxxx####xxxx###.",
+		"...x####xxxx####xxxx####xxxx#...",
+		".....###xxxx####xxxx####xxx.....",
+		".......#xxxx####xxxx####x.......",
+		".........###xxxx####xxx.........",
+		"...........#xxxx####x...........",
+		".............xxx###.............",
+		"...............x#..............."
+	},
+	{
+		"...............@o...............",
+		".............@@@ooo.............",
+		"...........o@@@@oooo@...........",
+		".........ooo@@@@oooo@@@.........",
+		".......o@@@@oooo@@@@oooo@.......",
+		".....ooo@@@@oooo@@@@oooo@@@.....",
+		"...@oooo@@@@oooo@@@@oooo@@@@o...",
+		".@@@oooo@@@@oooo@@@@oooo@@@@ooo.",
+		".ooo@@@@oooo@@@@oooo@@@@oooo@@@.",
+		"...o@@@@oooo@@@@oooo@@@@oooo@...",
+		".....@@@oooo@@@@oooo@@@@ooo.....",
+		".......@oooo@@@@oooo@@@@o.......",
+		".........@@@oooo@@@@ooo.........",
+		"...........@oooo@@@@o...........",
+		".............ooo@@@.............",
+		"...............o@..............."
+	}
+};
diff --git a/src/game.c b/src/game.c
new file mode 100644
index 0000000..b4baeca
--- /dev/null
+++ b/src/game.c
@@ -0,0 +1,90 @@
+#include <string.h>
+#include "game.h"
+#include "data_test.h"
+#include "gfx.h"
+
+#define TILE_W	32
+#define TILE_H	16
+
+void draw_tile(int tid, int x, int y, int light);
+void convert_tile_data(unsigned char *dest, const char *src);
+
+static unsigned char test_tiles[2][TILE_W * TILE_H / 8 * NBPL];
+
+int game_init(void)
+{
+	int i;
+
+	for(i=0; i<2; i++) {
+		convert_tile_data(test_tiles[i], test_tiles_cpix[i][0]);
+	}
+	return 0;
+}
+
+void game_draw(void)
+{
+	draw_tile(0, 32, 16, 0);
+}
+
+
+void draw_tile(int tid, int x, int y, int light)
+{
+	int i;
+
+	unsigned char *dest = bplptr[0] + (y * SCANSZ * NBPL) + x / 8;
+	unsigned char *src = test_tiles[tid];
+
+	for(i=0; i<TILE_H * NBPL; i++) {
+		memcpy(dest, src, TILE_W / 8);
+		dest += SCANSZ;
+		src += TILE_W / 8;
+	}
+}
+
+static inline int charpix_color(char c)
+{
+	switch(c) {
+	case '#':
+		return 1;
+	case 'x':
+		return 2;
+	case '@':
+		return 3;
+	case 'o':
+		return 4;
+	default:
+	case '.':
+		break;
+	}
+	return 0;
+}
+
+#define TILE_SCANSZ	(TILE_W / 8)
+void convert_tile_data(unsigned char *dest, const char *src)
+{
+	int i, j, k;
+	unsigned char *bptr[NBPL];
+
+	for(i=0; i<NBPL; i++) {
+		bptr[i] = dest + TILE_SCANSZ * i;
+	}
+
+	for(i=0; i<TILE_H; i++) {
+		for(j=0; j<TILE_W; j++) {
+			int col = charpix_color(*src++);
+
+			for(k=0; k<NBPL; k++) {
+				*bptr[k] = (*bptr[k] << 1) | (col & 1);
+				col >>= 1;
+
+				if((j & 7) == 7) {
+					bptr[k]++;
+				}
+			}
+		}
+
+		for(j=0; j<NBPL; j++) {
+			bptr[j] += TILE_SCANSZ * (NBPL - 1);
+		}
+	}
+}
diff --git a/src/game.h b/src/game.h
new file mode 100644
index 0000000..69c14e8
--- /dev/null
+++ b/src/game.h
@@ -0,0 +1,7 @@
+#ifndef GAME_H_
+#define GAME_H_
+
+int game_init(void);
+void game_draw(void);
+
+#endif	/* GAME_H_ */
-- 
1.7.10.4