Re: [PATCH v9 13/13] ASoC: qcom: q6apm: Add support for early buffer mapping on DSP

[Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>]

On 5/12/26 5:09 AM, Jens Glathe wrote:
> On 02.04.26 10:11, Srinivas Kandagatla wrote:
>> Buffers are allocated on pcm_new and mapped in the dsp on every
>> prepare call, which is inefficient and unnecessary.
>>
>> Add new functions q6apm_[un]map_memory_fixed_region to map it on
>> to dsp only once after allocation.
>>
>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
>> ---
>>   sound/soc/qcom/qdsp6/audioreach.c |  60 ------------
>>   sound/soc/qcom/qdsp6/audioreach.h |   5 +-
>>   sound/soc/qcom/qdsp6/q6apm-dai.c  | 107 ++++++++++++++++++---
>>   sound/soc/qcom/qdsp6/q6apm.c      | 151 +++++++++++++++++++-----------
>>   sound/soc/qcom/qdsp6/q6apm.h      |  14 +--
>>   5 files changed, 202 insertions(+), 135 deletions(-)
> 
> Hi there,
> 
> I had to revert this patch from the series to get back working sound on
> sc8280xp (Blackrock) on 7.1. And hitting the right patch was pure luck,
> tbh, since I integrated the series on 6.19 and couldn't apply the last 2
> cleanly. But figured these are cleanup/refactoring and left them out.
> 
> The errors I'm getting on Blackrock are these:
> 
> Mai 11 21:26:32 volterra kernel: q6apm-dai 3000000.remoteproc:glink-
> edge:gpr:service@1:dais: Audio Start: Buffer Allocation failed rc = -22
> Mai 11 21:26:32 volterra kernel: q6apm-dai 3000000.remoteproc:glink-
> edge:gpr:service@1:dais: ASoC error (-22): at
> snd_soc_pcm_component_new() on 3000000.remoteproc:glink-
> edge:gpr:service@1:dais
Could you please test this change on your setup and let me know if it
helps? If so, I’ll send out a proper fix.
This is a workaround for a known issue, I will add more details in the
patch that I will send once we know if it fixes the issue.

------------------------>cut<----------------------------

diff --git a/sound/soc/qcom/qdsp6/q6apm-dai.c
b/sound/soc/qcom/qdsp6/q6apm-dai.c
index ede19fdea6e9..8a1a3d8a3398 100644
--- a/sound/soc/qcom/qdsp6/q6apm-dai.c
+++ b/sound/soc/qcom/qdsp6/q6apm-dai.c
@@ -497,7 +497,7 @@ static int q6apm_dai_pcm_new(struct
snd_soc_component *component, struct snd_soc
 {
        struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
        struct snd_pcm *pcm = rtd->pcm;
-       int size = BUFFER_BYTES_MAX;
+       int size = BUFFER_BYTES_MAX + 4096;
        int graph_id, ret;
        struct snd_pcm_substream *substream;
------------------------>cut<----------------------------


--srini


> 
> Since I'm way out of my depth here, I won't cite from the Great
> Hallucinator's analysis. Only reporting that this refactoring breaks
> sound on sc8280xp.
> 
> with best regards
> 
> Jens
>