[PATCH RFC v1 0/2] ASoC: meson: aiu: two fixes
Hello Jerome,
in this series I am proposing two fixes for the "aiu" driver, used on Amlogic Meson8, Meson8b, Meson8m2, GXBB, GXL and GXM SoCs.
The first patch is the result of me trying to understand the way how we get the DMA buffer and address for the audio data. I'm not an expert in terms of DMA. From what I understand we need to inform DMA core about the limitations of the hardware. In case of AIU it's DMA address registers only take 32 bits, so DMA core should be aware of this.
The second patch is what I could come up with to fix the infamous I2S buffer underrun issue, also called the "machine gun noise" (MGN) bug. After a lot of testing, debugging and comparing vendor code with the upstream "aiu" driver I have come up with this fix. I have written down my thoughts in the description of that patch. To be clear: these are my thoughts, unfortunately I have no way of proving this other than asking other people to test this patch (off-list I have already received positive feedback along with confirmation that both 2-ch and 6-ch audio are still working fine. Even with Kodi's menu - which is an easy way to reproduce the MGN bug - sound output is fine with this patch).
Please let me know what you think about these patches and especially the patch descriptions.
Martin Blumenstingl (2): ASoC: meson: aiu: fifo: Add missing dma_coerce_mask_and_coherent() ASoC: meson: aiu: Move AIU_I2S_MISC hold setting to aiu-fifo-i2s
sound/soc/meson/aiu-encoder-i2s.c | 33 ------------------------------- sound/soc/meson/aiu-fifo-i2s.c | 12 +++++++++++ sound/soc/meson/aiu-fifo.c | 6 ++++++ 3 files changed, 18 insertions(+), 33 deletions(-)
The FIFO registers which take an DMA-able address are only 32-bit wide on AIU. Add dma_coerce_mask_and_coherent() to make the DMA core aware of this limitation.
Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support") Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com --- sound/soc/meson/aiu-fifo.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/sound/soc/meson/aiu-fifo.c b/sound/soc/meson/aiu-fifo.c index 4ad23267cace..d67ff4cdabd5 100644 --- a/sound/soc/meson/aiu-fifo.c +++ b/sound/soc/meson/aiu-fifo.c @@ -5,6 +5,7 @@
#include <linux/bitfield.h> #include <linux/clk.h> +#include <linux/dma-mapping.h> #include <sound/pcm_params.h> #include <sound/soc.h> #include <sound/soc-dai.h> @@ -179,6 +180,11 @@ int aiu_fifo_pcm_new(struct snd_soc_pcm_runtime *rtd, struct snd_card *card = rtd->card->snd_card; struct aiu_fifo *fifo = dai->playback_dma_data; size_t size = fifo->pcm->buffer_bytes_max; + int ret; + + ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); + if (ret) + return ret;
snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV, card->dev, size, size);
The out-of-tree vendor driver uses the following approach to set the AIU_I2S_MISC register: 1) write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR 2) configure AIU_I2S_MUTE_SWAP[15:0] 3) write AIU_MEM_I2S_END_PTR 4) set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold mode") 5) set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always stays at 1 while for older drivers this bit is unset in step 4) 6) set AIU_I2S_MISC[2] to 0 7) write AIU_MEM_I2S_MASKS 8) toggle AIU_MEM_I2S_CONTROL[0] 9) toggle AIU_MEM_I2S_BUF_CNTL[0]
Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no interrupts are generated anymore. The way this bit is managed by the vendor driver as well as not getting any interrupts can mean that it's related to the FIFO and not the encoder.
Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it closer resembles the flow in the vendor kernel. While here also configure AIU_I2S_MISC[4] (documented as: "force each audio data to left or right according to the bit attached with the audio data") similar to how the vendor driver does this. This fixes the infamous and long-standing "machine gun noise" issue (a buffer underrun issue).
Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support") Reported-by: Christian Hewitt christianshewitt@gmail.com Reported-by: Geraldo Nascimento geraldogabriel@gmail.com Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com --- sound/soc/meson/aiu-encoder-i2s.c | 33 ------------------------------- sound/soc/meson/aiu-fifo-i2s.c | 12 +++++++++++ 2 files changed, 12 insertions(+), 33 deletions(-)
diff --git a/sound/soc/meson/aiu-encoder-i2s.c b/sound/soc/meson/aiu-encoder-i2s.c index 932224552146..67729de41a73 100644 --- a/sound/soc/meson/aiu-encoder-i2s.c +++ b/sound/soc/meson/aiu-encoder-i2s.c @@ -18,7 +18,6 @@ #define AIU_RST_SOFT_I2S_FAST BIT(0)
#define AIU_I2S_DAC_CFG_MSB_FIRST BIT(2) -#define AIU_I2S_MISC_HOLD_EN BIT(2) #define AIU_CLK_CTRL_I2S_DIV_EN BIT(0) #define AIU_CLK_CTRL_I2S_DIV GENMASK(3, 2) #define AIU_CLK_CTRL_AOCLK_INVERT BIT(6) @@ -36,37 +35,6 @@ static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component, enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0); }
-static void aiu_encoder_i2s_hold(struct snd_soc_component *component, - bool enable) -{ - snd_soc_component_update_bits(component, AIU_I2S_MISC, - AIU_I2S_MISC_HOLD_EN, - enable ? AIU_I2S_MISC_HOLD_EN : 0); -} - -static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd, - struct snd_soc_dai *dai) -{ - struct snd_soc_component *component = dai->component; - - switch (cmd) { - case SNDRV_PCM_TRIGGER_START: - case SNDRV_PCM_TRIGGER_RESUME: - case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: - aiu_encoder_i2s_hold(component, false); - return 0; - - case SNDRV_PCM_TRIGGER_STOP: - case SNDRV_PCM_TRIGGER_SUSPEND: - case SNDRV_PCM_TRIGGER_PAUSE_PUSH: - aiu_encoder_i2s_hold(component, true); - return 0; - - default: - return -EINVAL; - } -} - static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component, struct snd_pcm_hw_params *params) { @@ -353,7 +321,6 @@ static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream, }
const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = { - .trigger = aiu_encoder_i2s_trigger, .hw_params = aiu_encoder_i2s_hw_params, .hw_free = aiu_encoder_i2s_hw_free, .set_fmt = aiu_encoder_i2s_set_fmt, diff --git a/sound/soc/meson/aiu-fifo-i2s.c b/sound/soc/meson/aiu-fifo-i2s.c index 2388a2d0b3a6..d0a1090d6465 100644 --- a/sound/soc/meson/aiu-fifo-i2s.c +++ b/sound/soc/meson/aiu-fifo-i2s.c @@ -20,6 +20,8 @@ #define AIU_MEM_I2S_CONTROL_MODE_16BIT BIT(6) #define AIU_MEM_I2S_BUF_CNTL_INIT BIT(0) #define AIU_RST_SOFT_I2S_FAST BIT(0) +#define AIU_I2S_MISC_HOLD_EN BIT(2) +#define AIU_I2S_MISC_FORCE_LEFT_RIGHT BIT(4)
#define AIU_FIFO_I2S_BLOCK 256
@@ -90,6 +92,10 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, unsigned int val; int ret;
+ snd_soc_component_update_bits(component, AIU_I2S_MISC, + AIU_I2S_MISC_HOLD_EN, + AIU_I2S_MISC_HOLD_EN); + ret = aiu_fifo_hw_params(substream, params, dai); if (ret) return ret; @@ -117,6 +123,12 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, snd_soc_component_update_bits(component, AIU_MEM_I2S_MASKS, AIU_MEM_I2S_MASKS_IRQ_BLOCK, val);
+ snd_soc_component_update_bits(component, AIU_I2S_MISC, + AIU_I2S_MISC_FORCE_LEFT_RIGHT, + AIU_I2S_MISC_FORCE_LEFT_RIGHT); + snd_soc_component_update_bits(component, AIU_I2S_MISC, + AIU_I2S_MISC_HOLD_EN, 0); + return 0; }
Hi, Martin,
Thanks for working on this!
I will give it a test and let you know.
Thanks, Geraldo Nascimento
On Sun, Dec 05, 2021 at 07:08:16PM +0100, Martin Blumenstingl wrote:
The out-of-tree vendor driver uses the following approach to set the AIU_I2S_MISC register:
- write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR
- configure AIU_I2S_MUTE_SWAP[15:0]
- write AIU_MEM_I2S_END_PTR
- set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold mode")
- set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always stays at 1 while for older drivers this bit is unset in step 4)
- set AIU_I2S_MISC[2] to 0
- write AIU_MEM_I2S_MASKS
- toggle AIU_MEM_I2S_CONTROL[0]
- toggle AIU_MEM_I2S_BUF_CNTL[0]
Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no interrupts are generated anymore. The way this bit is managed by the vendor driver as well as not getting any interrupts can mean that it's related to the FIFO and not the encoder.
Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it closer resembles the flow in the vendor kernel. While here also configure AIU_I2S_MISC[4] (documented as: "force each audio data to left or right according to the bit attached with the audio data") similar to how the vendor driver does this. This fixes the infamous and long-standing "machine gun noise" issue (a buffer underrun issue).
Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support") Reported-by: Christian Hewitt christianshewitt@gmail.com Reported-by: Geraldo Nascimento geraldogabriel@gmail.com Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com
sound/soc/meson/aiu-encoder-i2s.c | 33 ------------------------------- sound/soc/meson/aiu-fifo-i2s.c | 12 +++++++++++ 2 files changed, 12 insertions(+), 33 deletions(-)
diff --git a/sound/soc/meson/aiu-encoder-i2s.c b/sound/soc/meson/aiu-encoder-i2s.c index 932224552146..67729de41a73 100644 --- a/sound/soc/meson/aiu-encoder-i2s.c +++ b/sound/soc/meson/aiu-encoder-i2s.c @@ -18,7 +18,6 @@ #define AIU_RST_SOFT_I2S_FAST BIT(0)
#define AIU_I2S_DAC_CFG_MSB_FIRST BIT(2) -#define AIU_I2S_MISC_HOLD_EN BIT(2) #define AIU_CLK_CTRL_I2S_DIV_EN BIT(0) #define AIU_CLK_CTRL_I2S_DIV GENMASK(3, 2) #define AIU_CLK_CTRL_AOCLK_INVERT BIT(6) @@ -36,37 +35,6 @@ static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component, enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0); }
-static void aiu_encoder_i2s_hold(struct snd_soc_component *component,
bool enable)-{
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,enable ? AIU_I2S_MISC_HOLD_EN : 0);-}
-static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *dai)-{
- struct snd_soc_component *component = dai->component;
- switch (cmd) {
- case SNDRV_PCM_TRIGGER_START:
- case SNDRV_PCM_TRIGGER_RESUME:
- case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
aiu_encoder_i2s_hold(component, false);return 0;- case SNDRV_PCM_TRIGGER_STOP:
- case SNDRV_PCM_TRIGGER_SUSPEND:
- case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
aiu_encoder_i2s_hold(component, true);return 0;- default:
return -EINVAL;- }
-}
static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component, struct snd_pcm_hw_params *params) { @@ -353,7 +321,6 @@ static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream, }
const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
- .trigger = aiu_encoder_i2s_trigger, .hw_params = aiu_encoder_i2s_hw_params, .hw_free = aiu_encoder_i2s_hw_free, .set_fmt = aiu_encoder_i2s_set_fmt,
diff --git a/sound/soc/meson/aiu-fifo-i2s.c b/sound/soc/meson/aiu-fifo-i2s.c index 2388a2d0b3a6..d0a1090d6465 100644 --- a/sound/soc/meson/aiu-fifo-i2s.c +++ b/sound/soc/meson/aiu-fifo-i2s.c @@ -20,6 +20,8 @@ #define AIU_MEM_I2S_CONTROL_MODE_16BIT BIT(6) #define AIU_MEM_I2S_BUF_CNTL_INIT BIT(0) #define AIU_RST_SOFT_I2S_FAST BIT(0) +#define AIU_I2S_MISC_HOLD_EN BIT(2) +#define AIU_I2S_MISC_FORCE_LEFT_RIGHT BIT(4)
#define AIU_FIFO_I2S_BLOCK 256
@@ -90,6 +92,10 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, unsigned int val; int ret;
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,AIU_I2S_MISC_HOLD_EN);- ret = aiu_fifo_hw_params(substream, params, dai); if (ret) return ret;
@@ -117,6 +123,12 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, snd_soc_component_update_bits(component, AIU_MEM_I2S_MASKS, AIU_MEM_I2S_MASKS_IRQ_BLOCK, val);
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_FORCE_LEFT_RIGHT,AIU_I2S_MISC_FORCE_LEFT_RIGHT);- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN, 0);- return 0;
}
-- 2.34.1
On 5 Dec 2021, at 10:08 pm, Martin Blumenstingl martin.blumenstingl@googlemail.com wrote:
The out-of-tree vendor driver uses the following approach to set the AIU_I2S_MISC register:
- write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR
- configure AIU_I2S_MUTE_SWAP[15:0]
- write AIU_MEM_I2S_END_PTR
- set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold
mode") 5) set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always stays at 1 while for older drivers this bit is unset in step 4) 6) set AIU_I2S_MISC[2] to 0 7) write AIU_MEM_I2S_MASKS 8) toggle AIU_MEM_I2S_CONTROL[0] 9) toggle AIU_MEM_I2S_BUF_CNTL[0]
Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no interrupts are generated anymore. The way this bit is managed by the vendor driver as well as not getting any interrupts can mean that it's related to the FIFO and not the encoder.
Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it closer resembles the flow in the vendor kernel. While here also configure AIU_I2S_MISC[4] (documented as: "force each audio data to left or right according to the bit attached with the audio data") similar to how the vendor driver does this. This fixes the infamous and long-standing "machine gun noise" issue (a buffer underrun issue).
Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support") Reported-by: Christian Hewitt christianshewitt@gmail.com Reported-by: Geraldo Nascimento geraldogabriel@gmail.com Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com
Thanks Martin.
Checked with WeTek Play 2 (GXBB), LePotato (GXL), and Khadas VIM2 (GXM) so I’m delighted to say:
Tested-by: Christian Hewitt christianshewitt@gmail.com
sound/soc/meson/aiu-encoder-i2s.c | 33 ------------------------------- sound/soc/meson/aiu-fifo-i2s.c | 12 +++++++++++ 2 files changed, 12 insertions(+), 33 deletions(-)
diff --git a/sound/soc/meson/aiu-encoder-i2s.c b/sound/soc/meson/aiu-encoder-i2s.c index 932224552146..67729de41a73 100644 --- a/sound/soc/meson/aiu-encoder-i2s.c +++ b/sound/soc/meson/aiu-encoder-i2s.c @@ -18,7 +18,6 @@ #define AIU_RST_SOFT_I2S_FAST BIT(0)
#define AIU_I2S_DAC_CFG_MSB_FIRST BIT(2) -#define AIU_I2S_MISC_HOLD_EN BIT(2) #define AIU_CLK_CTRL_I2S_DIV_EN BIT(0) #define AIU_CLK_CTRL_I2S_DIV GENMASK(3, 2) #define AIU_CLK_CTRL_AOCLK_INVERT BIT(6) @@ -36,37 +35,6 @@ static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component, enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0); }
-static void aiu_encoder_i2s_hold(struct snd_soc_component *component,
bool enable)-{
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,enable ? AIU_I2S_MISC_HOLD_EN : 0);-}
-static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *dai)-{
- struct snd_soc_component *component = dai->component;
- switch (cmd) {
- case SNDRV_PCM_TRIGGER_START:
- case SNDRV_PCM_TRIGGER_RESUME:
- case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
aiu_encoder_i2s_hold(component, false);return 0;- case SNDRV_PCM_TRIGGER_STOP:
- case SNDRV_PCM_TRIGGER_SUSPEND:
- case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
aiu_encoder_i2s_hold(component, true);return 0;- default:
return -EINVAL;- }
-}
static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component, struct snd_pcm_hw_params *params) { @@ -353,7 +321,6 @@ static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream, }
const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
- .trigger = aiu_encoder_i2s_trigger, .hw_params = aiu_encoder_i2s_hw_params, .hw_free = aiu_encoder_i2s_hw_free, .set_fmt = aiu_encoder_i2s_set_fmt,
diff --git a/sound/soc/meson/aiu-fifo-i2s.c b/sound/soc/meson/aiu-fifo-i2s.c index 2388a2d0b3a6..d0a1090d6465 100644 --- a/sound/soc/meson/aiu-fifo-i2s.c +++ b/sound/soc/meson/aiu-fifo-i2s.c @@ -20,6 +20,8 @@ #define AIU_MEM_I2S_CONTROL_MODE_16BIT BIT(6) #define AIU_MEM_I2S_BUF_CNTL_INIT BIT(0) #define AIU_RST_SOFT_I2S_FAST BIT(0) +#define AIU_I2S_MISC_HOLD_EN BIT(2) +#define AIU_I2S_MISC_FORCE_LEFT_RIGHT BIT(4)
#define AIU_FIFO_I2S_BLOCK 256
@@ -90,6 +92,10 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, unsigned int val; int ret;
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,AIU_I2S_MISC_HOLD_EN);- ret = aiu_fifo_hw_params(substream, params, dai); if (ret) return ret;
@@ -117,6 +123,12 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, snd_soc_component_update_bits(component, AIU_MEM_I2S_MASKS, AIU_MEM_I2S_MASKS_IRQ_BLOCK, val);
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_FORCE_LEFT_RIGHT,AIU_I2S_MISC_FORCE_LEFT_RIGHT);- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN, 0);- return 0;
}
-- 2.34.1
On Sun, Dec 05, 2021 at 07:08:16PM +0100, Martin Blumenstingl wrote:
The out-of-tree vendor driver uses the following approach to set the AIU_I2S_MISC register:
- write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR
- configure AIU_I2S_MUTE_SWAP[15:0]
- write AIU_MEM_I2S_END_PTR
- set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold mode")
- set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always stays at 1 while for older drivers this bit is unset in step 4)
- set AIU_I2S_MISC[2] to 0
- write AIU_MEM_I2S_MASKS
- toggle AIU_MEM_I2S_CONTROL[0]
- toggle AIU_MEM_I2S_BUF_CNTL[0]
Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no interrupts are generated anymore. The way this bit is managed by the vendor driver as well as not getting any interrupts can mean that it's related to the FIFO and not the encoder.
Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it closer resembles the flow in the vendor kernel. While here also configure AIU_I2S_MISC[4] (documented as: "force each audio data to left or right according to the bit attached with the audio data") similar to how the vendor driver does this. This fixes the infamous and long-standing "machine gun noise" issue (a buffer underrun issue).
Tested-by: Geraldo Nascimento geraldogabriel@gmail.com
---
About the test setup:
Board is from H96Pro+ TV BOX, Amlogic S912 with 3G RAM, 32GB eMMC and a QCA9377 SDIO wifi chip. Sticker in the underside of the board says CZ-S32-V6 which I suppose is the manufacturer's name/revision of the PCB.
Tested with Audacious, audio output is ALSA without any plugins such as dmix, etc.
First I made sure the problem was reproducible. Just skipping the track on Audacious from one point to another would result in severe noise. I then applied Martin's patch and noise is gone for good.
Thanks, Geraldo Nascimento
Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support") Reported-by: Christian Hewitt christianshewitt@gmail.com Reported-by: Geraldo Nascimento geraldogabriel@gmail.com Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com
sound/soc/meson/aiu-encoder-i2s.c | 33 ------------------------------- sound/soc/meson/aiu-fifo-i2s.c | 12 +++++++++++ 2 files changed, 12 insertions(+), 33 deletions(-)
diff --git a/sound/soc/meson/aiu-encoder-i2s.c b/sound/soc/meson/aiu-encoder-i2s.c index 932224552146..67729de41a73 100644 --- a/sound/soc/meson/aiu-encoder-i2s.c +++ b/sound/soc/meson/aiu-encoder-i2s.c @@ -18,7 +18,6 @@ #define AIU_RST_SOFT_I2S_FAST BIT(0)
#define AIU_I2S_DAC_CFG_MSB_FIRST BIT(2) -#define AIU_I2S_MISC_HOLD_EN BIT(2) #define AIU_CLK_CTRL_I2S_DIV_EN BIT(0) #define AIU_CLK_CTRL_I2S_DIV GENMASK(3, 2) #define AIU_CLK_CTRL_AOCLK_INVERT BIT(6) @@ -36,37 +35,6 @@ static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component, enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0); }
-static void aiu_encoder_i2s_hold(struct snd_soc_component *component,
bool enable)-{
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,enable ? AIU_I2S_MISC_HOLD_EN : 0);-}
-static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *dai)-{
- struct snd_soc_component *component = dai->component;
- switch (cmd) {
- case SNDRV_PCM_TRIGGER_START:
- case SNDRV_PCM_TRIGGER_RESUME:
- case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
aiu_encoder_i2s_hold(component, false);return 0;- case SNDRV_PCM_TRIGGER_STOP:
- case SNDRV_PCM_TRIGGER_SUSPEND:
- case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
aiu_encoder_i2s_hold(component, true);return 0;- default:
return -EINVAL;- }
-}
static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component, struct snd_pcm_hw_params *params) { @@ -353,7 +321,6 @@ static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream, }
const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
- .trigger = aiu_encoder_i2s_trigger, .hw_params = aiu_encoder_i2s_hw_params, .hw_free = aiu_encoder_i2s_hw_free, .set_fmt = aiu_encoder_i2s_set_fmt,
diff --git a/sound/soc/meson/aiu-fifo-i2s.c b/sound/soc/meson/aiu-fifo-i2s.c index 2388a2d0b3a6..d0a1090d6465 100644 --- a/sound/soc/meson/aiu-fifo-i2s.c +++ b/sound/soc/meson/aiu-fifo-i2s.c @@ -20,6 +20,8 @@ #define AIU_MEM_I2S_CONTROL_MODE_16BIT BIT(6) #define AIU_MEM_I2S_BUF_CNTL_INIT BIT(0) #define AIU_RST_SOFT_I2S_FAST BIT(0) +#define AIU_I2S_MISC_HOLD_EN BIT(2) +#define AIU_I2S_MISC_FORCE_LEFT_RIGHT BIT(4)
#define AIU_FIFO_I2S_BLOCK 256
@@ -90,6 +92,10 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, unsigned int val; int ret;
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,AIU_I2S_MISC_HOLD_EN);- ret = aiu_fifo_hw_params(substream, params, dai); if (ret) return ret;
@@ -117,6 +123,12 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, snd_soc_component_update_bits(component, AIU_MEM_I2S_MASKS, AIU_MEM_I2S_MASKS_IRQ_BLOCK, val);
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_FORCE_LEFT_RIGHT,AIU_I2S_MISC_FORCE_LEFT_RIGHT);- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN, 0);- return 0;
}
-- 2.34.1
On Sun 05 Dec 2021 at 19:08, Martin Blumenstingl martin.blumenstingl@googlemail.com wrote:
The out-of-tree vendor driver uses the following approach to set the AIU_I2S_MISC register:
- write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR
- configure AIU_I2S_MUTE_SWAP[15:0]
- write AIU_MEM_I2S_END_PTR
- set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold mode")
- set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always stays at 1 while for older drivers this bit is unset in step 4)
- set AIU_I2S_MISC[2] to 0
- write AIU_MEM_I2S_MASKS
- toggle AIU_MEM_I2S_CONTROL[0]
- toggle AIU_MEM_I2S_BUF_CNTL[0]
Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no interrupts are generated anymore. The way this bit is managed by the vendor driver as well as not getting any interrupts can mean that it's related to the FIFO and not the encoder.
Not necessarily. If the encoder stops pulling data, the FIFO will going over the DDR. Since it generates an IRQ after reading N bytes, IRQ would stop too. AFAIK, if the pipeline is stalled, the IRQ stops anyway
... but this is not really important
Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it closer resembles the flow in the vendor kernel. While here also configure AIU_I2S_MISC[4] (documented as: "force each audio data to left or right according to the bit attached with the audio data") similar to how the vendor driver does this.
I understand the part of HOLD, not about FORCE_LR. Is it necessary to fix the problem ? Have you tested without this change ?
This fixes the infamous and long-standing "machine gun noise" issue (a buffer underrun issue).
Well done ! It took us a while to nail it, Thanks a lot !!
Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support") Reported-by: Christian Hewitt christianshewitt@gmail.com Reported-by: Geraldo Nascimento geraldogabriel@gmail.com Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com
sound/soc/meson/aiu-encoder-i2s.c | 33 ------------------------------- sound/soc/meson/aiu-fifo-i2s.c | 12 +++++++++++ 2 files changed, 12 insertions(+), 33 deletions(-)
diff --git a/sound/soc/meson/aiu-encoder-i2s.c b/sound/soc/meson/aiu-encoder-i2s.c index 932224552146..67729de41a73 100644 --- a/sound/soc/meson/aiu-encoder-i2s.c +++ b/sound/soc/meson/aiu-encoder-i2s.c @@ -18,7 +18,6 @@ #define AIU_RST_SOFT_I2S_FAST BIT(0)
#define AIU_I2S_DAC_CFG_MSB_FIRST BIT(2) -#define AIU_I2S_MISC_HOLD_EN BIT(2) #define AIU_CLK_CTRL_I2S_DIV_EN BIT(0) #define AIU_CLK_CTRL_I2S_DIV GENMASK(3, 2) #define AIU_CLK_CTRL_AOCLK_INVERT BIT(6) @@ -36,37 +35,6 @@ static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component, enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0); }
-static void aiu_encoder_i2s_hold(struct snd_soc_component *component,
bool enable)-{
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,enable ? AIU_I2S_MISC_HOLD_EN : 0);-}
-static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *dai)-{
- struct snd_soc_component *component = dai->component;
- switch (cmd) {
- case SNDRV_PCM_TRIGGER_START:
- case SNDRV_PCM_TRIGGER_RESUME:
- case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
aiu_encoder_i2s_hold(component, false);return 0;- case SNDRV_PCM_TRIGGER_STOP:
- case SNDRV_PCM_TRIGGER_SUSPEND:
- case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
aiu_encoder_i2s_hold(component, true);return 0;- default:
return -EINVAL;- }
-}
static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component, struct snd_pcm_hw_params *params) { @@ -353,7 +321,6 @@ static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream, }
const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
- .trigger = aiu_encoder_i2s_trigger, .hw_params = aiu_encoder_i2s_hw_params, .hw_free = aiu_encoder_i2s_hw_free, .set_fmt = aiu_encoder_i2s_set_fmt,
diff --git a/sound/soc/meson/aiu-fifo-i2s.c b/sound/soc/meson/aiu-fifo-i2s.c index 2388a2d0b3a6..d0a1090d6465 100644 --- a/sound/soc/meson/aiu-fifo-i2s.c +++ b/sound/soc/meson/aiu-fifo-i2s.c @@ -20,6 +20,8 @@ #define AIU_MEM_I2S_CONTROL_MODE_16BIT BIT(6) #define AIU_MEM_I2S_BUF_CNTL_INIT BIT(0) #define AIU_RST_SOFT_I2S_FAST BIT(0) +#define AIU_I2S_MISC_HOLD_EN BIT(2) +#define AIU_I2S_MISC_FORCE_LEFT_RIGHT BIT(4)
#define AIU_FIFO_I2S_BLOCK 256
@@ -90,6 +92,10 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, unsigned int val; int ret;
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN,AIU_I2S_MISC_HOLD_EN);- ret = aiu_fifo_hw_params(substream, params, dai); if (ret) return ret;
@@ -117,6 +123,12 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, snd_soc_component_update_bits(component, AIU_MEM_I2S_MASKS, AIU_MEM_I2S_MASKS_IRQ_BLOCK, val);
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_FORCE_LEFT_RIGHT,AIU_I2S_MISC_FORCE_LEFT_RIGHT);
If it is necessary, even if we don't really understand why, it is fine by me. But if it is not, I would prefer we leave it out of it, or at least, make it a separate patch.
- snd_soc_component_update_bits(component, AIU_I2S_MISC,
AIU_I2S_MISC_HOLD_EN, 0);- return 0;
}
Hi Jerome,
On Mon, Dec 6, 2021 at 11:02 AM Jerome Brunet jbrunet@baylibre.com wrote:
On Sun 05 Dec 2021 at 19:08, Martin Blumenstingl martin.blumenstingl@googlemail.com wrote:
The out-of-tree vendor driver uses the following approach to set the AIU_I2S_MISC register:
- write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR
- configure AIU_I2S_MUTE_SWAP[15:0]
- write AIU_MEM_I2S_END_PTR
- set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold mode")
- set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always stays at 1 while for older drivers this bit is unset in step 4)
- set AIU_I2S_MISC[2] to 0
- write AIU_MEM_I2S_MASKS
- toggle AIU_MEM_I2S_CONTROL[0]
- toggle AIU_MEM_I2S_BUF_CNTL[0]
Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no interrupts are generated anymore. The way this bit is managed by the vendor driver as well as not getting any interrupts can mean that it's related to the FIFO and not the encoder.
Not necessarily. If the encoder stops pulling data, the FIFO will going over the DDR. Since it generates an IRQ after reading N bytes, IRQ would stop too. AFAIK, if the pipeline is stalled, the IRQ stops anyway
ah, right. so I think you're right: it can be either way
... but this is not really important
I'll remove that section from the description in v2
Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it closer resembles the flow in the vendor kernel. While here also configure AIU_I2S_MISC[4] (documented as: "force each audio data to left or right according to the bit attached with the audio data") similar to how the vendor driver does this.
I understand the part of HOLD, not about FORCE_LR. Is it necessary to fix the problem ? Have you tested without this change ?
On my Le Potato board (GXL / S905X) FORCE_LR is either enabled by the bootloader or being enabled is the default value. All versions of the vendor driver are also setting it in some way, including the latest one that I have access to [0]. I prefer to keep this explicit write in for two reasons: - we're not hit by surprise if some SoC/bootloaders don't set this bit by default - the code in the mainline does not skip anything that the vendor driver does
To specifically answer your question: I have not tried whether this bit needs to be set and if unsetting it manually breaks anything.
This fixes the infamous and long-standing "machine gun noise" issue (a buffer underrun issue).
Well done ! It took us a while to nail it, Thanks a lot !!
Thanks - this took a while to figure out but it's great to finally have it solved!
Best regards, Martin
[0] https://github.com/khadas/linux/blob/khadas-vims-4.9.y/sound/soc/amlogic/mes...
On Mon 06 Dec 2021 at 18:28, Martin Blumenstingl martin.blumenstingl@googlemail.com wrote:
Hi Jerome,
On Mon, Dec 6, 2021 at 11:02 AM Jerome Brunet jbrunet@baylibre.com wrote:
On Sun 05 Dec 2021 at 19:08, Martin Blumenstingl martin.blumenstingl@googlemail.com wrote:
The out-of-tree vendor driver uses the following approach to set the AIU_I2S_MISC register:
- write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR
- configure AIU_I2S_MUTE_SWAP[15:0]
- write AIU_MEM_I2S_END_PTR
- set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold mode")
- set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always stays at 1 while for older drivers this bit is unset in step 4)
- set AIU_I2S_MISC[2] to 0
- write AIU_MEM_I2S_MASKS
- toggle AIU_MEM_I2S_CONTROL[0]
- toggle AIU_MEM_I2S_BUF_CNTL[0]
Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no interrupts are generated anymore. The way this bit is managed by the vendor driver as well as not getting any interrupts can mean that it's related to the FIFO and not the encoder.
Not necessarily. If the encoder stops pulling data, the FIFO will going over the DDR. Since it generates an IRQ after reading N bytes, IRQ would stop too. AFAIK, if the pipeline is stalled, the IRQ stops anyway
ah, right. so I think you're right: it can be either way
... but this is not really important
I'll remove that section from the description in v2
Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it closer resembles the flow in the vendor kernel. While here also configure AIU_I2S_MISC[4] (documented as: "force each audio data to left or right according to the bit attached with the audio data") similar to how the vendor driver does this.
I understand the part of HOLD, not about FORCE_LR. Is it necessary to fix the problem ? Have you tested without this change ?
On my Le Potato board (GXL / S905X) FORCE_LR is either enabled by the bootloader or being enabled is the default value. All versions of the vendor driver are also setting it in some way,
+1 Would you mind adding a comment in the code saying just that - so we know why it's there ?
including the latest one that I have access to [0]. I prefer to keep this explicit write in for two reasons:
- we're not hit by surprise if some SoC/bootloaders don't set this bit
by default
- the code in the mainline does not skip anything that the vendor
driver does
You can bet I've skipped a fair share of what the vendor driver does, on purpose.
To specifically answer your question: I have not tried whether this bit needs to be set and if unsetting it manually breaks anything.
This fixes the infamous and long-standing "machine gun noise" issue (a buffer underrun issue).
Well done ! It took us a while to nail it, Thanks a lot !!
Thanks - this took a while to figure out but it's great to finally have it solved!
Best regards, Martin
[0] https://github.com/khadas/linux/blob/khadas-vims-4.9.y/sound/soc/amlogic/mes...
With this, feel free to repost without the RFC tag and with my
Acked-by: Jerome Brunet jbrunet@baylibre.com
participants (4)
-
Christian Hewitt -
Geraldo Nascimento -
Jerome Brunet -
Martin Blumenstingl