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

From: Rafael J. Wysocki
Date: Thu Feb 07 2008 - 18:10:56 EST


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
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