linux-kernel - Re: [rft] s2ram wakeup moves to .c, could fix few machines

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20080207225121.GE6096@elf.ucw.cz>
Date:	Thu, 7 Feb 2008 23:51:21 +0100
From:	Pavel Machek <pavel@....cz>
To:	"H. Peter Anvin" <hpa@...or.com>
Cc:	"Rafael J. Wysocki" <rjw@...k.pl>,
	kernel list <linux-kernel@...r.kernel.org>,
	Linux-pm mailing list <linux-pm@...ts.osdl.org>
Subject: Re: [rft] s2ram wakeup moves to .c, could fix few machines

On Thu 2008-02-07 14:46:25, H. Peter Anvin wrote:
> Pavel Machek wrote:
>>
>> This is probably more acceptable version of beep; but there are
>> probably even better ways to clean it...
>>
>>         if (wakeup_header.realmode_flags & 4) {
>>                 inb(97);
>>                 outb(0, 0x80);
>>                 outb(3, 97);
>>                 outb(0, 0x80);
>>                 outb(-74, 67);
>>                 outb(0, 0x80);
>>                 outb(-119, 66);
>>                 outb(0, 0x80);
>>                 outb(15, 66);
>>         }
>>
>
> What is available at this point -- are BIOS calls still accessible; are 
> interrupts running?

No interrupts. BIOS calls work on some machines, but I'd like this to
work when bios does not.

Actually, matthieu's code is probably better to start from:

+/* one ISA cycle @8Mhz */
+#define PAUSE outb %al, $0x80
+#define WAIT_100MS \
+       movl $800000, %eax; \
+       2: \
+       PAUSE; \
+       dec %eax; \
+       jne 2b
+
+/* What's the PIT rate */
+#define COUNT 0xf89
 #define BEEP \
-       inb     $97, %al;       \
-       outb    %al, $0x80;     \
-       movb    $3, %al;        \
-       outb    %al, $97;       \
-       outb    %al, $0x80;     \
-       movb    $-74, %al;      \
-       outb    %al, $67;       \
-       outb    %al, $0x80;     \
-       movb    $-119, %al;     \
-       outb    %al, $66;       \
-       outb    %al, $0x80;     \
-       movb    $15, %al;       \
-       outb    %al, $66;
+       /* enable counter 2 */ \
+       inb             $0x61, %al;     \
+       PAUSE;  \
+       orb     $3, %al; \
+       outb    %al, $0x61;     \
+       PAUSE;  \
+       /* set command for counter 2, 2 byte write */ \
+       movb    $0xB6, %al;     \
+       outb    %al, $0x43;     \
+       PAUSE;  \
+       /* select desired HZ */ \
+       movb    $(COUNT & 0xff), %al; \
+       outb    %al, $0x42;     \
+       PAUSE;  \
+       movb    $(COUNT >> 8), %al;     \
+       outb    %al, $0x42; \
+       WAIT_100MS; \
+       /* disable counter 2 */ \
+       inb             $0x61, %al;     \
+       PAUSE;  \
+       andb    $0xFC, %al; \
+       outb    %al, $0x61; \
+       WAIT_100MS
+
+#define CBEEP \
+       testl   $4, realmode_flags - wakeup_code; \
+       jz      1f; \
+       BEEP; \
+1:

...because it allows user to compute number of beeps.
							Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/