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

Rafael J. Wysocki
2008-02-09T13:48:03Z

On Saturday, 9 of February 2008, H. Peter Anvin wrote:
> Rafael J. Wysocki wrote:
> >
> > Consolidated patch is appended. I'll test it tomorrow on x86-64.
> >
> > I'd like to add the cleaned up beeping code to it and perhaps try to push it
> > for -mm testing without any further changes. We can still do more cleanups in
> > followup patches.
> >
>
> The other thing to figure out is to what extent we can clean up the
> conditionals in the video mode code by refactoring. All they really do
> here is save space by removing functionality not needed for wakeup,
> because I didn't know how much space was realistic.

OK, I have an idea.

For now, below is a patch that adds your beeping code to wakemain.c (on top of
the previous one). ;-)

Rafael

---
arch/x86/kernel/acpi/realmode/wakemain.c | 69 ++++++++++++++++++++++++++++---
1 file changed, 63 insertions(+), 6 deletions(-)

Index: linux-2.6/arch/x86/kernel/acpi/realmode/wakemain.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/acpi/realmode/wakemain.c
+++ linux-2.6/arch/x86/kernel/acpi/realmode/wakemain.c
@@ -3,20 +3,77 @@

extern volatile struct wakeup_header wakeup_header;

+static void udelay(int loops)
+{
+ while (loops--)
+ io_delay(); /* Approximately 1 us */
+}
+
+static void beep(unsigned int hz)
+{
+ u8 enable;
+
+ if (!hz) {
+ enable = 0x00; /* Turn off speaker */
+ } else {
+ u16 div = 1193181/hz;
+
+ outb(0xb6, 0x43); /* Ctr 2, squarewave, load, binary */
+ io_delay();
+ outb(div, 0x42); /* LSB of counter */
+ io_delay();
+ outb(div >> 8, 0x42); /* MSB of counter */
+ io_delay();
+
+ enable = 0x03; /* Turn on speaker */
+ }
+ inb(0x61); /* Dummy read of System Control Port B */
+ io_delay();
+ outb(enable, 0x61); /* Enable timer 2 output to speaker */
+ io_delay();
+}
+
+#define DOT_HZ 880
+#define DASH_HZ 587
+#define US_PER_DOT 125000
+
+/* Okay, this is totally silly, but it's kind of fun. */
+static void send_morse(const char *pattern)
+{
+ char s;
+
+ while ((s = *pattern++)) {
+ switch (s) {
+ case '.':
+ beep(DOT_HZ);
+ udelay(US_PER_DOT);
+ beep(0);
+ udelay(US_PER_DOT);
+ break;
+ case '-':
+ beep(DASH_HZ);
+ udelay(US_PER_DOT * 3);
+ beep(0);
+ udelay(US_PER_DOT);
+ break;
+ default: /* Assume it's a space */
+ udelay(US_PER_DOT * 3);
+ break;
+ }
+ }
+}
+
void main(void)
{
/* Kill machine if structures are wrong */
if (wakeup_header.real_magic != 0x12345678)
while(1);

- if (wakeup_header.realmode_flags & 4) {
- asm volatile("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");
- }
+ if (wakeup_header.realmode_flags & 4)
+ send_morse("...-");

- if (wakeup_header.realmode_flags & 1) {
+ if (wakeup_header.realmode_flags & 1)
asm volatile("lcallw $0xc000,$3");
-// ("movw %cs, %ax; movw %ax, %ds; movw %ax, %es; movw %ax, %ss");
- }

if (wakeup_header.realmode_flags & 2) {
/* Need to call BIOS */