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| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-01-18 08:04:23 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-01-18 08:18:16 +0100 |
| commit | 2da80b57c69a2a5ae0e16dead8cdbfab46f970bc (patch) | |
| tree | 402529def53a1b32066493f5581c3e1810d11a1d /sound/pci/hda/hda_intel.c | |
| parent | drm/i915: Pass the dma_addr_t array as const to rotate_pages() (diff) | |
| parent | Merge tag 'drm-intel-next-fixes-2016-01-14' of git://anongit.freedesktop.org/... (diff) | |
| download | linux-2da80b57c69a2a5ae0e16dead8cdbfab46f970bc.tar.xz linux-2da80b57c69a2a5ae0e16dead8cdbfab46f970bc.zip | |
Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next-queued
Pull in Dave's drm-next pull request to have a clean base for 4.6.
Also, we need the various atomic state extensions Maarten recently
created.
Conflicts are just adjacent changes that all resolve to nothing in git
diff.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'sound/pci/hda/hda_intel.c')
| -rw-r--r-- | sound/pci/hda/hda_intel.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 963f82430938..bff5c8b329d1 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -355,6 +355,8 @@ enum { ((pci)->device == 0x0d0c) || \ ((pci)->device == 0x160c)) +#define IS_BROXTON(pci) ((pci)->device == 0x5a98) + static char *driver_short_names[] = { [AZX_DRIVER_ICH] = "HDA Intel", [AZX_DRIVER_PCH] = "HDA Intel PCH", @@ -506,15 +508,36 @@ static void azx_init_pci(struct azx *chip) } } +/* + * In BXT-P A0, HD-Audio DMA requests is later than expected, + * and makes an audio stream sensitive to system latencies when + * 24/32 bits are playing. + * Adjusting threshold of DMA fifo to force the DMA request + * sooner to improve latency tolerance at the expense of power. + */ +static void bxt_reduce_dma_latency(struct azx *chip) +{ + u32 val; + + val = azx_readl(chip, SKL_EM4L); + val &= (0x3 << 20); + azx_writel(chip, SKL_EM4L, val); +} + static void hda_intel_init_chip(struct azx *chip, bool full_reset) { struct hdac_bus *bus = azx_bus(chip); + struct pci_dev *pci = chip->pci; if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) snd_hdac_set_codec_wakeup(bus, true); azx_init_chip(chip, full_reset); if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) snd_hdac_set_codec_wakeup(bus, false); + + /* reduce dma latency to avoid noise */ + if (IS_BROXTON(pci)) + bxt_reduce_dma_latency(chip); } /* calculate runtime delay from LPIB */ |