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]

Date:	Fri, 8 Feb 2008 00:09:04 +0100
From:	"Rafael J. Wysocki" <rjw@...k.pl>
To:	Pavel Machek <pavel@....cz>
Cc:	"H. Peter Anvin" <hpa@...or.com>,
	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 Thursday, 7 of February 2008, Pavel Machek wrote:
> 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.

Hm, it seems we can convert it at least partially to C.

Rafael
--
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/