ASoC: bcm2835-i2s: Set the PERIOD_BYTES min to 256 #6386
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Commit [1] set the minimum PERIOD_BYTES value to the product of the DMA burst size and 8. For the I2S interface on BCM2835 that equates to 16 where it used to be 256. ffmpeg uses the minimum value as its preferred value, leading to many, many very small periods, which affects performance and leads to complaints about DTS timestamps. Restore the previous behaviour and performance by making the bcm2835-i2s driver set a minimum PERIOD_BYTES value of 256. Link: raspberrypi#5709 [1] 300689f ("ASoC: soc-generic-dmaengine-pcm: set period_bytes_min based on maxburst") Signed-off-by: Phil Elwell <phil@raspberrypi.com>
popcornmix
added a commit
to raspberrypi/firmware
that referenced
this pull request
Sep 26, 2024
See: raspberrypi/linux#6368 kernel: tty/serial: pl011: Also unregister pl011_axi_platform_driver See: raspberrypi/linux#6380 kernel: overlays: wm8960-soundcard: Fix clock declaration See: raspberrypi/linux#6387 kernel: Fix speaker disabling issue after closing microphone app See: raspberrypi/linux#6383 kernel: ASoC: bcm2835-i2s: Set the PERIOD_BYTES min to 256 See: raspberrypi/linux#6386 kernel: drivers: media: imx500: Simplify the vblank control init See: raspberrypi/linux#6388
popcornmix
added a commit
to raspberrypi/rpi-firmware
that referenced
this pull request
Sep 26, 2024
See: raspberrypi/linux#6368 kernel: tty/serial: pl011: Also unregister pl011_axi_platform_driver See: raspberrypi/linux#6380 kernel: overlays: wm8960-soundcard: Fix clock declaration See: raspberrypi/linux#6387 kernel: Fix speaker disabling issue after closing microphone app See: raspberrypi/linux#6383 kernel: ASoC: bcm2835-i2s: Set the PERIOD_BYTES min to 256 See: raspberrypi/linux#6386 kernel: drivers: media: imx500: Simplify the vblank control init See: raspberrypi/linux#6388
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Commit [1] set the minimum PERIOD_BYTES value to the product of the DMA burst size and 8. For the I2S interface on BCM2835 that equates to 16 where it used to be 256. ffmpeg uses the minimum value as its preferred value, leading to many, many very small periods, which affects performance and leads to complaints about DTS timestamps.
Restore the previous behaviour and performance by making the bcm2835-i2s driver set a minimum PERIOD_BYTES value of 256.
Link: #5709
[1] 300689f ("ASoC: soc-generic-dmaengine-pcm: set period_bytes_min based on maxburst")