From aa79432946f4c217b5e6517190f0a4f15702e708 Mon Sep 17 00:00:00 2001
From: aramya <22577625+thamugadi@users.noreply.github.com>
Date: Sat, 1 Jul 2023 03:52:59 +0100
Subject: [PATCH] OFW client interface

---
 Makefile        |   4 +-
 entry/boot.c    | 162 ++++++++++--------------------------------------
 entry/boot.h    |  28 +--------
 entry/start.s   |   5 +-
 loader/def.fth  |   3 +-
 loader/load.fth |   3 -
 6 files changed, 40 insertions(+), 165 deletions(-)

diff --git a/Makefile b/Makefile
index 4c5c7dd..a306c3c 100644
--- a/Makefile
+++ b/Makefile
@@ -19,8 +19,8 @@ bootinfo.txt: loader/load.fth loader/def.fth
 	cat loader/load.fth >> bootinfo.txt
 	echo "</boot-script></chrp-boot>" >> bootinfo.txt
 kernel.elf: start.elf boot.elf 
-	$(PPC)-ld -Ttext=0x200000 start.elf boot.elf -o kernel.elf
-boot.elf: entry/boot.c 
+	$(PPC)-ld -Ttext=0x200000 -Tdata=0x300000 start.elf boot.elf -o kernel.elf
+boot.elf: entry/boot.c entry/boot.h 
 	$(PPC)-gcc -c entry/boot.c -o boot.elf
 start.elf: entry/start.s
 	$(PPC)-as -c entry/start.s -o start.elf
diff --git a/entry/boot.c b/entry/boot.c
index d70e43d..7574ac1 100644
--- a/entry/boot.c
+++ b/entry/boot.c
@@ -1,141 +1,45 @@
 #include "boot.h"
-void __stack_chk_fail_local(void){}
-void __eabi(void){} 
-void get_io_type(void)
+void __stack_chk_fail_local(void)
 {
-        if (*(unsigned char*)__VRAM__BEIGE == beige) IO_TYPE = beige;
-	else if (*(unsigned char*)__VRAM__MAC99 == mac99) IO_TYPE = mac99;
-	if (IO_TYPE == beige)
-	{
-		screen_width = (*(unsigned int*)(__VRAM__BEIGE+4));
-                screen_height = (*(unsigned int*)(__VRAM__BEIGE+8)); 
-
-	}
-	else if (IO_TYPE == mac99)
-	{
-		screen_width = (*(unsigned int*)(__VRAM__MAC99+4));
-                screen_height = (*(unsigned int*)(__VRAM__MAC99+8));
-	}
 }
-void init(void)
+void __eabi(void)
 {
-	if (IO_TYPE == beige)
+}
+
+int test(const char* name)
+{
+	struct
 	{
-		p_vram = __VRAM__BEIGE;
-		p_bios = __BIOS__BEIGE;
-		p_timer= __TIMR__BEIGE;
-	}
-	else if (IO_TYPE == mac99)
-	{
-		p_vram = __VRAM__MAC99;
-		p_bios = __BIOS__MAC99;
-		p_timer= __TIMR__MAC99;
-	}
+		char* service;
+		int n_args;
+		int n_rets;
+		char* arg;
+		int ret;
+	} ofw_arg;
+
+	const char _service[5] = "test";
+	ofw_arg.service = _service;
+
+	ofw_arg.n_args = 1;
+	ofw_arg.n_rets = 1;
+	ofw_arg.arg = name;
+
+	ofw(&ofw_arg);
+
+	return ofw_arg.ret;
 }
 
 void main(void)
 {
-	get_io_type();
-	init();
-	game_of_life();
-}
-
-void fillscreen(unsigned int* addr, unsigned char a, unsigned char b, unsigned char c, int n)
-{
-	unsigned char* ptr = addr;
-	for (unsigned int i = 0; i<n; i++)
+	asm volatile("stw 5, %0" : "=m"(ofw));
+	if (test("open"))
 	{
-		//24-bit VGA
-		*ptr = a;
-		ptr++;
-		*ptr = b;
-		ptr++;
-		*ptr = c;
-		ptr++;
-		*ptr = 0;
-		ptr++;
-	}
-}
-
-void memcpy(unsigned char* dest, unsigned char* src, int n)
-{
-	unsigned char* destination = dest;
-	unsigned char* source = src;
-	for (int i = 0; i<n; i++)
-	{
-		*destination = *source;
-		destination++; source++;
-	}
-}
-
-void game_of_life(void)
-{
-	int N = screen_width;
-	int i,j,ip1,jp1,nei;
-	unsigned int random;
-	unsigned char universe[N][N];
-	unsigned char universe2[N][N];
-	unsigned char* junk_beige = 0x81040000;
-	for (i = 0; i < N; i++) for (j = 0; j < N; j++)
-        {
-		if (IO_TYPE == mac99)
-		{
-			random = (*p_timer + *p_bios);
-                	if (!(random%7)) universe[i][j] = 1;
-        		else universe[i][j] = 0;
-			p_bios++;
-		}
-		else if (IO_TYPE == beige)
-		{
-			random = (*junk_beige);
-                        if (!(random%3)) universe[i][j] = 1;
-                        else universe[i][j] = 0;
-			junk_beige++;
-		}
-        }
-	for(;;)	
-	{
-		init();
-		memcpy(p_vram, p_vram+255, 400000);
-
-		p_vram += 400000;
-		for (i = 0; i < N; i++) for (j = 0; j < N; j++)
-		{
-			if (universe[i][j]) fillscreen(p_vram, 255,255,255,1);
-			else fillscreen(p_vram,200 ,210,5,1);
-			p_vram+=4;
-		}
-		for (i = 0; i < N; i++) for (j = 0; j < N; j++) universe2[i][j] = universe[i][j];
-		for (i = 0; i < N; i++) for (j = 0; j < N; j++)
-		{
-			nei = 0;
-			ip1 = i + 1;
-			jp1 = j + 1;
-			if (i == N) ip1=0;
-			if (j == N) jp1=0;
-			if (!i) ip1=N;
-			if (!j) jp1=N;
-			if (universe[i][jp1]) nei++;
-			if (universe[ip1][j]) nei++;
-			if (universe[i][j-1]) nei++;
-			if (universe[i-1][j]) nei++;
-			if (universe[ip1][jp1]) nei++;
-			if (universe[ip1][j-1]) nei++;
-			if (universe[i-1][jp1]) nei++;
-			if (universe[i-1][j-1]) nei++;
-
-			if (universe[i][j])
-         	       	{
-                	        if (nei == 2 || nei == 3) universe2[i][j] = universe[i][j];
-                        	else universe2[i][j] = 0;
-                	}
-                	else
-                	{
-                        	if (nei == 3) universe2[i][j] = 1;
-                        	else universe2[i][j] = universe[i][j];
-                	}
-
-		}
-                for (i = 0; i < N; i++) for (j = 0; j < N; j++) universe[i][j] = universe2[i][j];
+		asm("mr 27, 28");
+		asm("b $");
+	}
+	else
+	{
+		asm("mr 30, 31");
+		asm("b $");
 	}
 }
diff --git a/entry/boot.h b/entry/boot.h
index c0130b3..90bb3ec 100644
--- a/entry/boot.h
+++ b/entry/boot.h
@@ -1,26 +1,2 @@
-#define beige                   0xBE
-#define mac99                   0x5A
-
-#define __VRAM__BEIGE           0x80000000
-#define __BIOS__BEIGE           0xFFC00000
-#define __TIMR__BEIGE           0 //
-#define __VRAM__MAC99           0x81000000
-#define __BIOS__MAC99           0xFFF00000
-#define __TIMR__MAC99           0x80080038
-void __stack_chk_fail_local();
-
-unsigned char  IO_TYPE;
-unsigned int   screen_width;
-unsigned int   screen_height;
-
-unsigned char* p_vram;
-unsigned char* p_bios;
-unsigned char* p_timer;
-unsigned char u8_extract_bit(unsigned char n, unsigned char bit);
-void get_io_type(void);
-void init(void);
-void fillscreen(unsigned int* addr, unsigned char a, unsigned char b, unsigned char c, int n);
-void memcpy(unsigned char* dest, unsigned char* src, int n);
-unsigned char u8_extract_bit(unsigned char n, unsigned char bit);
-unsigned char u32_extract_bit(unsigned int n, unsigned char bit);
-
+void (*ofw)();
+void __eabi();
diff --git a/entry/start.s b/entry/start.s
index bb1d8b6..86c22ad 100644
--- a/entry/start.s
+++ b/entry/start.s
@@ -1,5 +1,4 @@
 .globl _start
+.globl ofw
 _start:
-stwu 1, -0x7fff(1)
-
-b main 
+b main
diff --git a/loader/def.fth b/loader/def.fth
index 84f57f5..7d2fc2c 100644
--- a/loader/def.fth
+++ b/loader/def.fth
@@ -1,5 +1,4 @@
-: initmsg ." powerpc-ofw-boot : Booting through OpenFirmware..." cr ;
-: startmsg ." Running Game of Life..." cr ;
+: initmsg ." powerpc-ofw-boot" cr ;
 : sup - dup abs = ;
 : inf dup sup 1 + ; 
 : diff = if 0 else -1 then ;
diff --git a/loader/load.fth b/loader/load.fth
index ed1fcfe..5af7f50 100644
--- a/loader/load.fth
+++ b/loader/load.fth
@@ -5,11 +5,8 @@ fba beige-vram = if screen-width  4 beige-vram + l! then
 fba beige-vram = if screen-height 8 beige-vram + l! then
 fba mac99-vram = if screen-width  4 mac99-vram + l! then
 fba mac99-vram = if screen-height 8 mac99-vram + l! then
-." informations stored :" cr
-fba a dump
 variable run
 -1 run !
 fba beige-vram diff fba mac99-vram diff and if hardware-error 0 run ! then
 run @ 0 = if 1 0 do 0 +loop then
-startmsg
 boot hd:,\boot\kernel.elf