X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;ds=sidebyside;f=lib_i386%2Frealmode.c;h=6cf273885b838ed55d1c2d02710a722ee4bc0f98;hb=b4983e16d150ab7d039704c310aacbd2f4dc1e0f;hp=372147cf246afee0adbdb05021ce0140792bcb4b;hpb=2262cfeef91458b01a1bfe3812ccbbfdf8b82807;p=u-boot

diff --git a/lib_i386/realmode.c b/lib_i386/realmode.c
index 372147cf24..6cf273885b 100644
--- a/lib_i386/realmode.c
+++ b/lib_i386/realmode.c
@@ -1,7 +1,7 @@
 /*
  * (C) Copyright 2002
  * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
- * 
+ *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
@@ -24,6 +24,7 @@
 #include <common.h>
 #include <asm/io.h>
 #include <asm/ptrace.h>
+#include <asm/realmode.h>
 
 
 #define REALMODE_BASE    ((char*)0x7c0)
@@ -32,38 +33,63 @@
 
 extern char realmode_enter;
 
+int realmode_setup(void)
+{
+	/* copy the realmode switch code */
+	if (i386boot_realmode_size > (REALMODE_MAILBOX-REALMODE_BASE)) {
+		printf("realmode switch too large (%ld bytes, max is %d)\n",
+		       i386boot_realmode_size, (REALMODE_MAILBOX-REALMODE_BASE));
+		return -1;
+	}
+
+	memcpy(REALMODE_BASE, (void*)i386boot_realmode, i386boot_realmode_size);
+	asm("wbinvd\n");
+
+	return 0;
+}
 
 int enter_realmode(u16 seg, u16 off, struct pt_regs *in, struct pt_regs *out)
 {
-	
+
 	/* setup out thin bios emulation */
 	if (bios_setup()) {
 		return -1;
 	}
-		
-	/* copy the realmode switch code */
-	if (i386boot_realmode_size > (REALMODE_MAILBOX-REALMODE_BASE)) {
-		printf("realmode switch too large (%ld bytes, max is %d)\n", 
-		       i386boot_realmode_size, (REALMODE_MAILBOX-REALMODE_BASE));
+
+	if (realmode_setup()) {
 		return -1;
 	}
-	
-	memcpy(REALMODE_BASE, i386boot_realmode, i386boot_realmode_size);
-		
-	
+
 	in->eip = off;
 	in->xcs = seg;
-	if (3>in->esp & 0xffff) {
+	if (3>(in->esp & 0xffff)) {
 		printf("Warning: entering realmode with sp < 4 will fail\n");
 	}
-	
+
 	memcpy(REALMODE_MAILBOX, in, sizeof(struct pt_regs));
-	
-	__asm__ volatile ( 
+	asm("wbinvd\n");
+
+	__asm__ volatile (
 		 "lcall $0x20,%0\n"  : :  "i" (&realmode_enter) );
 
+	asm("wbinvd\n");
 	memcpy(out, REALMODE_MAILBOX, sizeof(struct pt_regs));
 
 	return out->eax;
 }
 
+
+/* This code is supposed to access a realmode interrupt
+ * it does currently not work for me */
+int enter_realmode_int(u8 lvl, struct pt_regs *in, struct pt_regs *out)
+{
+	/* place two instructions at 0x700 */
+	writeb(0xcd, 0x700);  /* int $lvl */
+	writeb(lvl, 0x701);
+	writeb(0xcb, 0x702);  /* lret */
+	asm("wbinvd\n");
+
+	enter_realmode(0x00, 0x700, in, out);
+
+	return out->eflags&1;
+}