From: Robin Krens <robin@robinkrens.nl>
Date: Wed, 8 Jun 2022 22:03:11 +0000 (+0200)
Subject: out call to ports with inline asm + c variables
X-Git-Url: https://robinkrens.nl/gitweb/?a=commitdiff_plain;h=64ce7b85586b85f39e009bb294c6c4c4782d1753;p=swan-dev

out call to ports with inline asm + c variables

squash of:
commit 0b368932d654cdbd81d682d36897c74fa1106485
commit a58ede133445902c0a13da0392cac600e72538bf
---

diff --git a/Makefile b/Makefile
index f949274..5ee33f7 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,9 @@ ADIR = objs
 SDIR = src
 INC = -Iinc
 
-CFLAGS = -march=v30 -ffreestanding # use NEC v30 chip
+CFLAGS = -march=v30# use NEC v30 chip
+CFLAGS += -ffreestanding# no stdlib
+CFLAGS += -fno-pic# for use of inline asm
 
 _OBJS = entry.o main.o # todo: make sure entry is forced as entry point for linker
 
diff --git a/src/entry.S b/src/entry.S
index e1393e5..e5fae8b 100644
--- a/src/entry.S
+++ b/src/entry.S
@@ -22,7 +22,7 @@ _start:
 	mov %ax,%bx
 	mov %ax,%bp
 	mov %ax,%ss
-	
+
 	# set stack pointer for wonderswan
 	# color
 	mov $0xFE00 - 2,%ax
diff --git a/src/main.c b/src/main.c
index 502d63c..dc651f1 100644
--- a/src/main.c
+++ b/src/main.c
@@ -18,13 +18,27 @@ unsigned char bgtile_pal[] = {
 unsigned char lol[5] = { 0xAA, 0x2, 0x3, 0x4, 0x5};
 unsigned char lol2[5] = { 0x1, 0x2, 0x3, 0x4, 0x5};
 unsigned char lol3[5] = { 0x1, 0x2, 0x3, 0x4, 0x5};
-#define PALETTE (*(volatile unsigned *)0xFE00)
 #define PALETTE_T (volatile unsigned *)0xFE00
 #define SPRITE_T (volatile unsigned *)0x4000
 
 /* bss */
 static unsigned char blaat[100];
 
+void outport(unsigned char portnr, unsigned char val)
+{
+	__asm__(
+		"mov %1, %%dl\n\t"
+		"out %0, (%%dx)"
+		:
+		:"r"(val), "r"(portnr)
+		:);
+}
+
+void init_video(void)
+{
+
+}
+
 int main(void)
 {
 	lol[0] = 0xDD;
@@ -33,6 +47,10 @@ int main(void)
 	blaat[0] = 0xEE;
 	blaat[1] = 0xEE;
 	blaat[32] = 0xEE;
+
+	init_video();
+	outport(0x15, 0xEE);
+	while(1);
 	
 	unsigned char * ptr = PALETTE_T;
 	for (int i = 0; i < sizeof(bgtile_pal); ++i) {