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Subject[PATCH 6/6] cpuid neatening.
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Roll all the cpuid asm into one __cpuid call.  It's a little neater,
and also means only one place to patch for paravirtualization.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Index: working-2.6.18-rc2-hg-paravirt/include/asm-i386/processor.h
===================================================================
--- working-2.6.18-rc2-hg-paravirt.orig/include/asm-i386/processor.h 2006-07-21 20:27:59.000000000 +1000
+++ working-2.6.18-rc2-hg-paravirt/include/asm-i386/processor.h 2006-07-21 21:50:49.000000000 +1000
@@ -143,6 +143,18 @@
#define X86_EFLAGS_VIP 0x00100000 /* Virtual Interrupt Pending */
#define X86_EFLAGS_ID 0x00200000 /* CPUID detection flag */

+static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
+ unsigned int *ecx, unsigned int *edx)
+{
+ /* ecx is often an input as well as an output. */
+ __asm__("cpuid"
+ : "=a" (*eax),
+ "=b" (*ebx),
+ "=c" (*ecx),
+ "=d" (*edx)
+ : "0" (*eax), "2" (*ecx));
+}
+
/*
* Generic CPUID function
* clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
@@ -150,24 +162,18 @@
*/
static inline void cpuid(unsigned int op, unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx)
{
- __asm__("cpuid"
- : "=a" (*eax),
- "=b" (*ebx),
- "=c" (*ecx),
- "=d" (*edx)
- : "0" (op), "c"(0));
+ *eax = op;
+ *ecx = 0;
+ __cpuid(eax, ebx, ecx, edx);
}

/* Some CPUID calls want 'count' to be placed in ecx */
static inline void cpuid_count(int op, int count, int *eax, int *ebx, int *ecx,
- int *edx)
+ int *edx)
{
- __asm__("cpuid"
- : "=a" (*eax),
- "=b" (*ebx),
- "=c" (*ecx),
- "=d" (*edx)
- : "0" (op), "c" (count));
+ *eax = op;
+ *ecx = count;
+ __cpuid(eax, ebx, ecx, edx);
}

/*
@@ -175,42 +181,30 @@
*/
static inline unsigned int cpuid_eax(unsigned int op)
{
- unsigned int eax;
+ unsigned int eax, ebx, ecx, edx;

- __asm__("cpuid"
- : "=a" (eax)
- : "0" (op)
- : "bx", "cx", "dx");
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return eax;
}
static inline unsigned int cpuid_ebx(unsigned int op)
{
- unsigned int eax, ebx;
+ unsigned int eax, ebx, ecx, edx;

- __asm__("cpuid"
- : "=a" (eax), "=b" (ebx)
- : "0" (op)
- : "cx", "dx" );
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return ebx;
}
static inline unsigned int cpuid_ecx(unsigned int op)
{
- unsigned int eax, ecx;
+ unsigned int eax, ebx, ecx, edx;

- __asm__("cpuid"
- : "=a" (eax), "=c" (ecx)
- : "0" (op)
- : "bx", "dx" );
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return ecx;
}
static inline unsigned int cpuid_edx(unsigned int op)
{
- unsigned int eax, edx;
+ unsigned int eax, ebx, ecx, edx;

- __asm__("cpuid"
- : "=a" (eax), "=d" (edx)
- : "0" (op)
- : "bx", "cx");
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return edx;
}

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