-----Original Message----- From: Takashi Iwai [mailto:tiwai@suse.de] Sent: Thursday, December 17, 2015 3:44 PM To: Zhang, Xiong Y Cc: alsa-devel@alsa-project.org; Yang, Libin; Lu, Han Subject: Re: [alsa-devel] [PATCH] ALSA: hda - Set intel hda controller power at freeze() and thaw()
On Thu, 17 Dec 2015 07:58:44 +0100, Xiong Zhang wrote:
It takes three minutes to enter into hibernation on some OEM SKL machines and we see many codec spurious response after thaw()
opertion.
This is because HDA is still in D0 state after freeze() call and pci_pm_freeze/pci_pm_freeze_noirq() don't set D3 hot in pci_bus
driver.
It seems bios still access HDA when system enter into freeze state, HDA will receive codec response interrupt immediately after thaw() call. Because of this unexpected interrupt, HDA enter into a abnormal state and slow down the system enter into hibernation.
In this patch, we put HDA into D3 hot state in azx_freeze_noirq() and put HDA into D0 state in azx_thaw_noirq().
A slight concern is whether this would cause any impact on older chipsets. I don't believe it would, but BIOSen are often crazy sensitive about such a detail.
Maybe safer to limit this to SKL+? I guess Broxton should be covered as well?
As the issue fixed by the patch is only found on SKL, I agree to limit it to SKL+. And apply it to other old platforms later if necessary.
BTW: We have tested it on BDW and SKL. It works on both platforms.
[Zhang, Xiong Y] Ok, I will apply the fix to SKL+. But how could I identify the HDA is SKL+ 1) HDA device ID or define macro IS_SKL_PLUS with DID, this means hard code 2) use AZX_DCAPS_I915_POWERWELL, this means applying it to HSW+ 3) add a new AZX_DCAPS_xxxx bit, but the bit for pci->driver_date is valuable and hda_intel driver has used most of the bit. Only bit 11, 22 and 31 are left.
thanks