From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753131AbXLNODy (ORCPT ); Fri, 14 Dec 2007 09:03:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751871AbXLNODq (ORCPT ); Fri, 14 Dec 2007 09:03:46 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:51348 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751805AbXLNODp (ORCPT ); Fri, 14 Dec 2007 09:03:45 -0500 Date: Fri, 14 Dec 2007 15:03:17 +0100 From: Ingo Molnar To: Rene Herman Cc: "David P. Reed" , Thomas Gleixner , linux-kernel@vger.kernel.org, Ingo Molnar , "H. Peter Anvin" , Pavel Machek , Alan Cox Subject: Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc. Message-ID: <20071214140317.GA1007@elte.hu> References: <469578CD.3080609@reed.com> <1184216528.12353.203.camel@chaos> <1184218962.12353.209.camel@chaos> <46964352.7040301@reed.com> <1184253339.12353.223.camel@chaos> <469697C6.50903@reed.com> <1184274754.12353.254.camel@chaos> <4761F193.7090400@reed.com> <20071214131502.GA14359@elte.hu> <47628842.5060908@keyaccess.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47628842.5060908@keyaccess.nl> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Rene Herman wrote: > On 14-12-07 14:15, Ingo Molnar wrote: > >> wow, cool fix! (I remember that there were other systems as well that are >> affected by port 0x80 muckery - i thought we had removed port 0x80 >> accesses long ago.) >> >> how about the simpler fix below, as a first-level approach? We can >> then remove the _p in/out sequences after this. > > Your version does the same thing that the version from Pavel/David > does for 32-bit at least. well, if you carefully look at the code it's not the "same" but a similar but cleaner thing - it moves this quirk out of a common include file. I take back the "simpler" characterisation - my patch indeed ended up being almost the same as David's. >> +/* >> + * Some legacy devices need delays for IN/OUT sequences. Most are >> + * probably not needed but it's the safest to just do this short delay: >> + */ >> +void native_io_delay(void) >> +{ >> + udelay(1); >> +} > > Also note the thread(s) on LKML where 2 us was decided to be a nicely > conservative value: yep, i have updated the delay to 2 usecs. The latest patch is below, as queued up in x86.git. (not yet queued up for .24 - it's pending testing and more feedback, etc.) Ingo -----------------> Subject: x86: fix in_p/out_p crashes From: David P. Reed Do not use port 0x80, it can cause crashes, see: http://bugzilla.kernel.org/show_bug.cgi?id=6307 http://bugzilla.kernel.org/show_bug.cgi?id=9511 Replace use of outb to "unused" diagnostic port 0x80 for time delay with udelay based time delay on x86_64 architecture machines. Fix for bugs 9511 and 6307 in bugzilla, plus bugs reported in bugzilla.redhat.com. Derived from suggestion (that didn't compile) by Pavel Machek, and tested, also based on measurements of typical timings of out's collated by Rene Herman from many in the community. This patch fixes a number of bugs known to cause problems on HP Pavilion dv9000z and dv6000z laptops - in the form of solid freezes when hwclock is used to show or set the time. Also, it potentially improves bus utilization on SMP machines, by using a waiting process that doesn't tie up the ISA/LPC bus for 1 or 2 microseconds. [ mingo@elte.hu: minor restructuring, 32-bit support. ] Signed-off-by: David P. Reed Signed-off-by: Ingo Molnar --- arch/x86/boot/compressed/misc_32.c | 8 ++++---- arch/x86/boot/compressed/misc_64.c | 8 ++++---- arch/x86/kernel/quirks.c | 10 ++++++++++ include/asm-x86/io_32.h | 5 +---- include/asm-x86/io_64.h | 14 +++++--------- 5 files changed, 24 insertions(+), 21 deletions(-) Index: linux-x86.q/arch/x86/boot/compressed/misc_32.c =================================================================== --- linux-x86.q.orig/arch/x86/boot/compressed/misc_32.c +++ linux-x86.q/arch/x86/boot/compressed/misc_32.c @@ -276,10 +276,10 @@ static void putstr(const char *s) RM_SCREEN_INFO.orig_y = y; pos = (x + cols * y) * 2; /* Update cursor position */ - outb_p(14, vidport); - outb_p(0xff & (pos >> 9), vidport+1); - outb_p(15, vidport); - outb_p(0xff & (pos >> 1), vidport+1); + outb(14, vidport); + outb(0xff & (pos >> 9), vidport+1); + outb(15, vidport); + outb(0xff & (pos >> 1), vidport+1); } static void* memset(void* s, int c, unsigned n) Index: linux-x86.q/arch/x86/boot/compressed/misc_64.c =================================================================== --- linux-x86.q.orig/arch/x86/boot/compressed/misc_64.c +++ linux-x86.q/arch/x86/boot/compressed/misc_64.c @@ -269,10 +269,10 @@ static void putstr(const char *s) RM_SCREEN_INFO.orig_y = y; pos = (x + cols * y) * 2; /* Update cursor position */ - outb_p(14, vidport); - outb_p(0xff & (pos >> 9), vidport+1); - outb_p(15, vidport); - outb_p(0xff & (pos >> 1), vidport+1); + outb(14, vidport); + outb(0xff & (pos >> 9), vidport+1); + outb(15, vidport); + outb(0xff & (pos >> 1), vidport+1); } static void* memset(void* s, int c, unsigned n) Index: linux-x86.q/arch/x86/kernel/quirks.c =================================================================== --- linux-x86.q.orig/arch/x86/kernel/quirks.c +++ linux-x86.q/arch/x86/kernel/quirks.c @@ -3,9 +3,19 @@ */ #include #include +#include #include +/* + * Some legacy devices need delays for IN/OUT sequences. Most are + * probably not needed but it's the safest to just do this short delay: + */ +void native_io_delay(void) +{ + udelay(2); +} + #if defined(CONFIG_X86_IO_APIC) && defined(CONFIG_SMP) && defined(CONFIG_PCI) static void __devinit quirk_intel_irqbalance(struct pci_dev *dev) Index: linux-x86.q/include/asm-x86/io_32.h =================================================================== --- linux-x86.q.orig/include/asm-x86/io_32.h +++ linux-x86.q/include/asm-x86/io_32.h @@ -250,10 +250,7 @@ static inline void flush_write_buffers(v #endif /* __KERNEL__ */ -static inline void native_io_delay(void) -{ - asm volatile("outb %%al,$0x80" : : : "memory"); -} +extern void native_io_delay(void); #if defined(CONFIG_PARAVIRT) #include Index: linux-x86.q/include/asm-x86/io_64.h =================================================================== --- linux-x86.q.orig/include/asm-x86/io_64.h +++ linux-x86.q/include/asm-x86/io_64.h @@ -35,13 +35,7 @@ * - Arnaldo Carvalho de Melo */ -#define __SLOW_DOWN_IO "\noutb %%al,$0x80" - -#ifdef REALLY_SLOW_IO -#define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO -#else -#define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO -#endif +extern void native_io_delay(void); /* * Talk about misusing macros.. @@ -54,7 +48,8 @@ __asm__ __volatile__ ("out" #s " %" s1 " #define __OUT(s,s1,x) \ __OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \ -__OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));} \ +__OUT1(s##_p,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); \ +native_io_delay(); } \ #define __IN1(s) \ static inline RETURN_TYPE in##s(unsigned short port) { RETURN_TYPE _v; @@ -64,7 +59,8 @@ __asm__ __volatile__ ("in" #s " %" s2 "1 #define __IN(s,s1,i...) \ __IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \ -__IN1(s##_p) __IN2(s,s1,"w") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \ +__IN1(s##_p) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; \ +native_io_delay(); } \ #define __INS(s) \ static inline void ins##s(unsigned short port, void * addr, unsigned long count) \