Messages in this thread |  | | | Date | Tue, 10 Oct 2006 12:39:10 +0200 | | From | Pavel Machek <> | | Subject | Re: 2.6.18 suspend regression on Intel Macs |
| |
Hi!
> Well, I'm not sure it qualifies as a regression, because AFAIK no > official kernels can s2ram/resume Intel Macs correctly out of the box. ...
> There has already been some discussion about the SCI_EN ACPI control bit > not being set when the Mactel boxes come out of suspend to ram. > http://marc.theaimsgroup.com/?l=linux-acpi&m=114957637501557&w=2 > http://marc.theaimsgroup.com/?l=linux-kernel&m=115005083610700&w=2 > http://bugme.osdl.org/show_bug.cgi?id=6670 > > The symptom is: > irq 9: nobody cared (try booting with the "irqpoll" option) > Disabling IRQ #9 > when the system comes out of sleep, making ACPI non-functional. > > Two days after having released 2.6.17, Linus commited a fix for this > issue in his tree (commit 5603509137940f4cbc577281cee62110d4097b1b):
If fix was in 2.6.18-gitX, yes, that probably counts as a regression.
> I since then used lightly patched 2.6.17 kernels on my MacMini without a > problem. With the release of 2.6.18, I decided to switch to a vanilla > kernel but I realized that the above issue reappeared. > > I tracked it down to the ACPI merge that took place on July 1st. More > precisely the commit 967440e3be1af06ad4dc7bb18d2e3c16130fe067 (ACPI: > ACPICA 20060623) contains the following hunk: > > @@ -635,6 +663,25 @@ acpi_status acpi_hw_register_write(u8 us > > case ACPI_REGISTER_PM1_CONTROL: /* 16-bit access */ > > + /* > + * Perform a read first to preserve certain bits (per ACPI spec) > + * > + * Note: This includes SCI_EN, we never want to change this bit > + */ > + status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK, > + ACPI_REGISTER_PM1_CONTROL, > + &read_value); > + if (ACPI_FAILURE(status)) { > + goto unlock_and_exit; > + } > + > + /* Insert the bits to be preserved */ > + > + ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS, > + read_value); > + > + /* Now we can write the data */ > + > status = > acpi_hw_low_level_write(16, value, > &acpi_gbl_FADT->xpm1a_cnt_blk); > > > which makes Linus' fix a no-op, because it disallows setting the SCI_EN > bit.
Okay, just submit a (tested) patch. (And add massive comments why it is neccessary on mac mini). 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@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |