From: Matthias Kruk <m@m10k.eu>
Date: Wed, 6 May 2020 04:00:45 +0000 (+0900)
Subject: Add VGA system process
X-Git-Url: https://git.corax.cc/?a=commitdiff_plain;h=b58a04e159e5663cb63f467d63f470ac28806c56;p=corax

Add VGA system process
---

diff --git a/config.h b/config.h
index 341b667..7cad81f 100644
--- a/config.h
+++ b/config.h
@@ -63,7 +63,7 @@
 #define CONFIG_ELF 0
 
 #define CONFIG_KBD 1
-#define CONFIG_VGA 0
+#define CONFIG_VGA 1
 
 /* klibc configuration */
 #define CONFIG_SNPRINTF_FLAG_MINUS 0
diff --git a/sys/Makefile b/sys/Makefile
index 1170973..61c8ab7 100644
--- a/sys/Makefile
+++ b/sys/Makefile
@@ -1,4 +1,4 @@
-DEPS = kbd
+DEPS = kbd vga
 PHONY = $(DEPS) clean
 OUTPUT = initfs.a
 INCLUDES = -I.. -I../include
@@ -9,7 +9,9 @@ all: $(OUTPUT)
 
 kbd.ko: kbd
 
-$(OUTPUT): initfs.o kbd.ko
+vga.ko: vga
+
+$(OUTPUT): initfs.o kbd.ko vga.ko
 	ar -rc $@ $^
 
 updateinitfs:
diff --git a/sys/vga/Makefile b/sys/vga/Makefile
new file mode 100644
index 0000000..8e4552b
--- /dev/null
+++ b/sys/vga/Makefile
@@ -0,0 +1,26 @@
+OBJECTS = main.o
+OUTPUT = vga
+MODULE = vga.ko
+
+INCLUDES = -I../../include -I../..
+CFLAGS = -m32 -Wall -nostdlib -nodefaultlibs -nostartfiles -ffreestanding \
+	 -nostdinc -fno-builtin -fno-builtin-memcpy
+LIBS = ../../libc/libc.a
+CFLAGS += $(INCLUDES)
+
+ASFLAGS = $(CFLAGS)
+PHONY = clean
+
+all: $(MODULE)
+
+$(MODULE): $(OUTPUT)
+	ld -r --oformat=elf32-i386 -m elf_i386 -b binary -o $@ $<
+	cp $@ ../
+
+$(OUTPUT): $(OBJECTS)
+	gcc -static $(CFLAGS) -o $@ $^ $(LIBS)
+
+clean:
+	rm -f $(OBJECTS) $(OUTPUT)
+
+.PHONY: $(PHONY)
diff --git a/sys/vga/main.c b/sys/vga/main.c
new file mode 100644
index 0000000..8f52c7c
--- /dev/null
+++ b/sys/vga/main.c
@@ -0,0 +1,120 @@
+#include <sys/mman.h>
+#include <corax/ipc.h>
+#include <crxstd.h>
+#include <string.h>
+#include <stdio.h>
+
+enum vgacolor {
+	BLACK = 0,
+	BLUE,
+	GREEN,
+	CYAN,
+	RED,
+	MAGENTA,
+	BROWN,
+	LGRAY,
+	GRAY,
+	LBLUE,
+	LGREEN,
+	LCYAN,
+	LRED,
+	LMAGENTA,
+	YELLOW,
+	WHITE
+};
+
+#define FG(c)            ((unsigned short)(((c) & 0xf) << 8))
+#define BG(c)            ((unsigned short)(((c) & 0xf) << 12))
+
+#define VGA_BUFFER_ADDR   ((void*)0xb8000)
+#define VGA_BUFFER_COLS   80
+#define VGA_BUFFER_ROWS   24
+#define VGA_ROW_BYTES     (VGA_BUFFER_COLS << 1)
+#define VGA_SCROLL_SIZE   (VGA_BUFFER_COLS * (VGA_BUFFER_ROWS - 1))
+#define VGA_SCROLL_BYTES  (VGA_BUFFER_SIZE << 1)
+#define VGA_BUFFER_SIZE   (VGA_BUFFER_COLS * VGA_BUFFER_ROWS)
+#define VGA_BUFFER_BYTES  (VGA_BUFFER_SIZE << 1)
+
+struct context {
+	unsigned short *buffer;
+	long offset;
+	unsigned short attrs;
+};
+
+static void _putchar(struct context *ctx, int c)
+{
+	if(c == '\n') {
+		ctx->offset += VGA_BUFFER_COLS -
+			(ctx->offset % VGA_BUFFER_COLS);
+	} else {
+		if(ctx->offset >= VGA_BUFFER_SIZE) {
+			ctx->offset = VGA_SCROLL_SIZE;
+			memcpy((void*)ctx->buffer,
+			       (void*)ctx->buffer + VGA_ROW_BYTES,
+			       VGA_SCROLL_BYTES);
+			memset((void*)ctx->buffer + VGA_SCROLL_BYTES,
+			       0, VGA_ROW_BYTES);
+		}
+
+		ctx->buffer[ctx->offset++] = ctx->attrs | (c & 0xff);
+	}
+
+	return;
+}
+
+static int _puts(struct context *ctx, const char *s)
+{
+	int i;
+
+	for(i = 0; s[i]; i++) {
+		_putchar(ctx, s[i]);
+	}
+
+	return(i);
+}
+
+int main(int argc, char *argv[])
+{
+	struct context ctx;
+	char line[80];
+
+	ctx.buffer = mmap(VGA_BUFFER_ADDR, 0x1000, PROT_READ | PROT_WRITE,
+			  MAP_PHYS, 0, 0);
+
+	if(!ctx.buffer) {
+		/* nothing to do if we can't get access to the VGA buffer */
+		return(1);
+	}
+
+	ctx.offset = VGA_BUFFER_SIZE;
+	ctx.attrs = FG(LGRAY) | BG(BLACK);
+	memset(ctx.buffer, 0, VGA_BUFFER_SIZE);
+
+	snprintf(line, sizeof(line), "VGA video memory mapped at %p\n",
+		 ctx.buffer);
+
+	_puts(&ctx, line);
+
+	while(1) {
+		struct cxmsg msg;
+		int err;
+
+		memset(&msg, 0, sizeof(msg));
+
+		err = cxrecv(PID_ANY, &msg);
+
+		/* FIXME: Validate message */
+		/* FIXME: Only accept messages from IO process */
+
+		if(!err) {
+			err = _puts(&ctx, (const char*)msg.cm_data);
+		}
+
+		msg.cm_retval = err;
+		cxsend(msg.cm_src, &msg);
+	}
+
+	munmap(ctx.buffer, 0x1000);
+
+	return(0);
+}