Enable CR4.VME to improve the performance of vm86 emulation.

Setting this bit eliminates the calls to the vm86 monitor to handle
interrupts and exceptions that occur while executing programs in vm86
mode.

Signed-off-by: Asit Mallick <asit.k.mallick@intel.com>
Signed-off-by: Arun Sharma <arun.sharma@intel.com>

diff --git a/tools/firmware/vmxassist/Makefile b/tools/firmware/vmxassist/Makefile
index 17ef50b76b1e90be35315723327ce5145991db67..e5560a946342ac43f30f94fd0501078a801f8adb 100644 (file)
--- a/tools/firmware/vmxassist/Makefile
+++ b/tools/firmware/vmxassist/Makefile
@@ -24,7 +24,7 @@ include $(XEN_ROOT)/tools/Rules.mk
 # The emulator code lives in ROM space
 TEXTADDR=0x000D0000
 
-DEFINES=-DDEBUG -DTEXTADDR=${TEXTADDR} -D_ACPI_
+DEFINES=-DDEBUG -DENABLE_VME -DTEXTADDR=${TEXTADDR}
 XENINC=-I$(XEN_ROOT)/xen/include -I$(XEN_ROOT)/tools/libxc
 #DEFINES=-DDEBUG -DTEST -DTEXTADDR=${TEXTADDR}
 #XENINC=-I/home/leendert/xen/xeno-unstable.bk/xen/include

diff --git a/tools/firmware/vmxassist/machine.h b/tools/firmware/vmxassist/machine.h
index 5d448ef13b203f7f0a49ea17d6efc33cb83ae79d..fd5779af6f88f8a77d4946dbe6b9259e835caad4 100644 (file)
--- a/tools/firmware/vmxassist/machine.h
+++ b/tools/firmware/vmxassist/machine.h
@@ -40,7 +40,8 @@
 #define EFLAGS_TF      (1 << 8)
 #define EFLAGS_IF      (1 << 9)
 #define EFLAGS_DF      (1 << 10)
-#define EFLAGS_VM      (1 << 17)
+#define EFLAGS_IOPL (3 << 12)
+#define EFLAGS_VM      ((1 << 17) | EFLAGS_IOPL)
 #define EFLAGS_VIF     (1 << 19)
 #define EFLAGS_VIP     (1 << 20)
 
@@ -109,6 +110,9 @@ struct tss {
        unsigned short  _5;
        unsigned short  _6;
        unsigned short  iomap_base;
+#ifdef ENABLE_VME
+       unsigned long   int_redir[8];
+#endif
        unsigned char   iomap[8192];
 };
 
@@ -177,7 +181,6 @@ get_cr4(void)
         return rv;
 }
 
-#ifdef TEST
 static inline void
 set_cr3(unsigned addr)
 {
@@ -190,6 +193,7 @@ set_cr4(unsigned value)
        __asm__ __volatile__("movl %0, %%cr4" : /* no outputs */ : "r"(value));
 }
 
+#ifdef TEST
 static inline void
 breakpoint(void)
 {

diff --git a/tools/firmware/vmxassist/setup.c b/tools/firmware/vmxassist/setup.c
index f572ae1698653e32091e285f6d24eb6e69b9aaa7..19324d1d5c95fe38c90e95cd454fe81352df22d1 100644 (file)
--- a/tools/firmware/vmxassist/setup.c
+++ b/tools/firmware/vmxassist/setup.c
@@ -121,7 +121,7 @@ void
 setup_gdt(void)
 {
        /* setup task state segment */
-       memset(&tss, 0, sizeof(0));
+       memset(&tss, 0, sizeof(tss));
        tss.ss0 = DATA_SELECTOR;
        tss.esp0 = (unsigned) stack_top - 4*4;
        tss.iomap_base = offsetof(struct tss, iomap);
@@ -353,6 +353,9 @@ main()
 #endif
        setup_gdt();
        setup_idt();
+#ifdef ENABLE_VME
+       set_cr4(get_cr4() | CR4_VME); 
+#endif
        setup_ctx();
        setup_pic();
        start_bios();