From: mpi <mpi@openbsd.org>
Date: Mon, 27 Apr 2015 07:20:57 +0000 (+0000)
Subject: Correctly write the 64bits of the HID 1, 4 and 5 registers.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=462c954b1417812430caf64326665a1fa34ca46c;p=openbsd

Correctly write the 64bits of the HID 1, 4 and 5 registers.

This makes the secondary cpu of my PowerMac as fast as the primary one,
and divide the build time by 3 with a GENERIC.MP kernel on MP G5s

Found thanks to MP kernel profiling.

ok dlg@, miod@
---

diff --git a/sys/arch/powerpc/powerpc/cpu_subr.c b/sys/arch/powerpc/powerpc/cpu_subr.c
index 5f8235270c6..54c8bde0161 100644
--- a/sys/arch/powerpc/powerpc/cpu_subr.c
+++ b/sys/arch/powerpc/powerpc/cpu_subr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu_subr.c,v 1.7 2015/03/31 16:00:38 mpi Exp $	*/
+/*	$OpenBSD: cpu_subr.c,v 1.8 2015/04/27 07:20:57 mpi Exp $	*/
 
 /*
  * Copyright (c) 2013 Martin Pieuchot
@@ -215,7 +215,8 @@ ppc64_mfhid1(void)
 void
 ppc64_mthid1(u_int64_t val)
 {
-	__asm volatile ("mtspr 1009,%0; mtspr 1009,%0; isync;" :: "r" (val));
+	__asm volatile ("sldi %0,%0,32; or %0,%0,%0+1;"
+	    "mtspr 1009,%0; mtspr 1009,%0; isync;" :: "r" (val));
 }
 
 u_int64_t
@@ -231,7 +232,8 @@ ppc64_mfhid4(void)
 void
 ppc64_mthid4(u_int64_t val)
 {
-	__asm volatile ("sync; mtspr 1012,%0; isync;" :: "r" (val));
+	__asm volatile ("sldi %0,%0,32; or %0,%0,%0+1;"
+	    "sync; mtspr 1012,%0; isync;" :: "r" (val));
 }
 
 u_int64_t
@@ -247,5 +249,6 @@ ppc64_mfhid5(void)
 void
 ppc64_mthid5(u_int64_t val)
 {
-	__asm volatile ("sync; mtspr 1014,%0; isync;" :: "r" (val));
+	__asm volatile ("sldi %0,%0,32; or %0,%0,%0+1;"
+	    "sync; mtspr 1014,%0; isync;" :: "r" (val));
 }