Re: [stable] Suspend regression in stable kernel 2.6.27.4 on Mac mini Core Duo

Rafael J. Wysocki
2008-11-13T22:13:33Z

On Thursday, 13 of November 2008, Tino Keitel wrote:
> On Wed, Nov 12, 2008 at 22:41:08 +0100, Rafael J. Wysocki wrote:
> > On Wednesday, 12 of November 2008, Tino Keitel wrote:
> > > On Wed, Nov 12, 2008 at 01:03:54 +0100, Rafael J. Wysocki wrote:
> > >
> > > [...]
> > >
> > > > Also, can you check this patch on top of 2.6.27.4 and see what happens?
> > >
> > > With that patch, resume works (although I used 2.6.27.5 and not
> > > 2.6.27.5, if that matters).
> >
> > It shouldn't really matter.
> >
> > Thanks for testing and please send me the output of dmidecode.
> > It seems that blacklisting may be the only way to handle your box. :-(
>
> Attached.

Please try the appended patch on top of the Linus' tree.

Thanks,
Rafael

---
drivers/acpi/sleep/main.c | 40 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 39 insertions(+), 1 deletion(-)

Index: linux-2.6/drivers/acpi/sleep/main.c
===================================================================
--- linux-2.6.orig/drivers/acpi/sleep/main.c
+++ linux-2.6/drivers/acpi/sleep/main.c
@@ -104,6 +104,18 @@ void __init acpi_s4_no_nvs(void)
s4_no_nvs = true;
}

+/*
+ * According to the ACPI specification the BIOS should make sure that ACPI is
+ * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states. Still,
+ * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
+ * on such systems during resume. Unfortunately that doesn't help in
+ * particularly pathological cases in which SCI_EN has to be set directly on
+ * resume, although the specification states very clearly that this flag is
+ * owned by the hardware. The set_sci_en_on_resume variable will be set in such
+ * cases.
+ */
+static bool set_sci_en_on_resume;
+
/**
* acpi_pm_disable_gpes - Disable the GPEs.
*/
@@ -249,7 +261,11 @@ static int acpi_suspend_enter(suspend_st
}

/* If ACPI is not enabled by the BIOS, we need to enable it here. */
- acpi_enable();
+ if (set_sci_en_on_resume)
+ acpi_set_register(ACPI_BITREG_SCI_ENABLE, 1);
+ else
+ acpi_enable();
+
/* Reprogram control registers and execute _BFS */
acpi_leave_sleep_state_prep(acpi_state);

@@ -337,6 +353,12 @@ static int __init init_old_suspend_order
return 0;
}

+static int __init init_set_sci_en_on_resume(const struct dmi_system_id *d)
+{
+ set_sci_en_on_resume = true;
+ return 0;
+}
+
static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
{
.callback = init_old_suspend_ordering,
@@ -354,6 +376,22 @@ static struct dmi_system_id __initdata a
DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
},
},
+ {
+ .callback = init_set_sci_en_on_resume,
+ .ident = "Apple MacBook 1,1",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBook1,1"),
+ },
+ },
+ {
+ .callback = init_set_sci_en_on_resume,
+ .ident = "Apple MacMini 1,1",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Macmini1,1"),
+ },
+ },
{},
};
#endif /* CONFIG_SUSPEND */