linux/sound
Maciej S. Szmigiero 04f8773a3e ALSA: emu10k1: add a IOMMU workaround
The Audigy 2 CA0102 chip (but most likely others from the emu10k1 family,
too) has a problem that from time to time it likes to do few DMA reads a
bit beyond its normal allocation and gets very confused if these reads get
blocked by a IOMMU.

For the first (reserved) page this happens multiple times at every
playback, for various synth pages it happens randomly, rarely for PCM
playback buffers and the page table memory itself.
All these reads seem to follow a similar pattern, observed read offsets
beyond the allocation end were 0x00, 0x40, 0x80 and 0xc0 (PCI cache line
multiples), so it looks like the device tries to accesses up to 256 extra
bytes.

As a workaround let's widen these DMA allocations by an extra page if we
detect that the device is behind a non-passthrough IOMMU (the DMA memory
should be relatively plenty on IOMMU systems).

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-02-14 07:46:55 +01:00
..
ac97 ALSA: ac97: kconfig: Remove select of undefined symbol AC97 2018-02-12 08:16:39 +01:00
aoa License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
arm Merge remote-tracking branches 'asoc/topic/ac97', 'asoc/topic/ac97-mfd', 'asoc/topic/amd' and 'asoc/topic/arizona-mfd' into asoc-next 2017-11-10 21:31:02 +00:00
atmel ASoC: Updates for v4.14 2017-09-04 14:50:49 +02:00
core vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
drivers Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-29 16:50:58 -08:00
firewire vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
hda ALSA: hda: Copying sync power state helper to core 2018-02-12 13:59:39 +01:00
i2c ASoC: Updates for v4.15 2017-11-13 15:45:57 +01:00
isa ALSA: gus: Delete an error message for a failed memory allocation in snd_gf1_dma_transfer_block() 2017-11-29 09:29:36 +01:00
mips ALSA: sgio2audio: Improve a size determination in snd_sgio2audio_create() 2017-11-29 09:29:31 +01:00
oss vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
parisc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci ALSA: emu10k1: add a IOMMU workaround 2018-02-14 07:46:55 +01:00
pcmcia ALSA: pcmcia: constify snd_pcm_ops structures 2017-08-19 11:02:21 +02:00
ppc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sh ALSA: sh: aica: Convert timers to use timer_setup() 2017-10-05 08:20:17 +02:00
soc ASoC: Updates for v4.16 2018-02-07 12:11:09 -08:00
sparc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
spi License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
synth ASoC: Updates for v4.15 2017-11-13 15:45:57 +01:00
usb Merge branch 'topic/fixes' into for-linus 2018-02-12 09:36:26 +01:00
x86 main drm pull for v4.13 2017-07-09 18:48:37 -07:00
ac97_bus.c
Kconfig ASoC: Updates for v4.15 2017-11-13 15:45:57 +01:00
last.c
Makefile ASoC: Updates for v4.15 2017-11-13 15:45:57 +01:00
sound_core.c sound: Remove leftover msnd init declarations 2018-01-11 17:10:34 +01:00