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Diffstat (limited to 'arch/x86/lib/realmode.c')
-rw-r--r--arch/x86/lib/realmode.c20
1 files changed, 8 insertions, 12 deletions
diff --git a/arch/x86/lib/realmode.c b/arch/x86/lib/realmode.c
index 6aa0f23..5a525ee 100644
--- a/arch/x86/lib/realmode.c
+++ b/arch/x86/lib/realmode.c
@@ -26,11 +26,7 @@
#include <asm/ptrace.h>
#include <asm/realmode.h>
-#define REALMODE_MAILBOX ((char*)0xe00)
-
-extern ulong __realmode_start;
-extern ulong __realmode_size;
-extern char realmode_enter;
+#define REALMODE_MAILBOX ((char *)0xe00)
int realmode_setup(void)
{
@@ -63,15 +59,14 @@ int enter_realmode(u16 seg, u16 off, struct pt_regs *in, struct pt_regs *out)
in->eip = off;
in->xcs = seg;
- if (3>(in->esp & 0xffff)) {
+ if ((in->esp & 0xffff) < 4)
printf("Warning: entering realmode with sp < 4 will fail\n");
- }
memcpy(REALMODE_MAILBOX, in, sizeof(struct pt_regs));
asm("wbinvd\n");
__asm__ volatile (
- "lcall $0x20,%0\n" : : "i" (&realmode_enter) );
+ "lcall $0x20,%0\n" : : "i" (&realmode_enter));
asm("wbinvd\n");
memcpy(out, REALMODE_MAILBOX, sizeof(struct pt_regs));
@@ -79,9 +74,10 @@ int enter_realmode(u16 seg, u16 off, struct pt_regs *in, struct pt_regs *out)
return out->eax;
}
-
-/* This code is supposed to access a realmode interrupt
- * it does currently not work for me */
+/*
+ * 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 */
@@ -92,5 +88,5 @@ int enter_realmode_int(u8 lvl, struct pt_regs *in, struct pt_regs *out)
enter_realmode(0x00, 0x700, in, out);
- return out->eflags&1;
+ return out->eflags & 0x00000001;
}