[PATCH 4.4 031/117] ALSA: hda - disable dynamic clock gating on Broxton before reset

From: Greg Kroah-Hartman
Date: Sun Feb 14 2016 - 19:42:30 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Libin Yang <libin.yang@xxxxxxxxxxxxxxx>

commit 6639484ddaf6707b41082c9fa9ca9af342df6402 upstream.

On Broxton, to make sure the reset controller works properly,
MISCBDCGE bit (bit 6) in CGCTL (0x48) of PCI configuration space
need be cleared before reset and set back to 1 after reset.
Otherwise, it may prevent the CORB/RIRB logic from being reset.

Signed-off-by: Libin Yang <libin.yang@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/pci/hda/hda_intel.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -90,6 +90,8 @@ enum {
#define NVIDIA_HDA_ENABLE_COHBIT 0x01

/* Defines for Intel SCH HDA snoop control */
+#define INTEL_HDA_CGCTL 0x48
+#define INTEL_HDA_CGCTL_MISCBDCGE (0x1 << 6)
#define INTEL_SCH_HDA_DEVC 0x78
#define INTEL_SCH_HDA_DEVC_NOSNOOP (0x1<<11)

@@ -528,10 +530,21 @@ static void hda_intel_init_chip(struct a
{
struct hdac_bus *bus = azx_bus(chip);
struct pci_dev *pci = chip->pci;
+ u32 val;

if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
snd_hdac_set_codec_wakeup(bus, true);
+ if (IS_BROXTON(pci)) {
+ pci_read_config_dword(pci, INTEL_HDA_CGCTL, &val);
+ val = val & ~INTEL_HDA_CGCTL_MISCBDCGE;
+ pci_write_config_dword(pci, INTEL_HDA_CGCTL, val);
+ }
azx_init_chip(chip, full_reset);
+ if (IS_BROXTON(pci)) {
+ pci_read_config_dword(pci, INTEL_HDA_CGCTL, &val);
+ val = val | INTEL_HDA_CGCTL_MISCBDCGE;
+ pci_write_config_dword(pci, INTEL_HDA_CGCTL, val);
+ }
if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
snd_hdac_set_codec_wakeup(bus, false);