mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Chandana Kishori Chiluveru <chandana.chiluveru@oss.qualcomm.com>
To: konrad.dybcio@oss.qualcomm.com, Vinod Koul <vkoul@kernel.org>,
	Frank Li <Frank.Li@kernel.org>,
	bjorn.andersson@oss.qualcomm.com
Cc: praveen.talari@oss.qualcomm.com, linux-arm-msm@vger.kernel.org,
	dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
	mukesh.savaliya@oss.qualcomm.com,
	Chandana Kishori Chiluveru <chandana.chiluveru@oss.qualcomm.com>
Subject: [PATCH] dmaengine: qcom: gpi: Fix SE ID and SE Protocol fields widths in SCRATCH_0
Date: Mon, 20 Jul 2026 08:27:34 -0700	[thread overview]
Message-ID: <20260720-fix_se_id_and_se_protocol_fields-v1-1-e41dbb107d97@oss.qualcomm.com> (raw)

GPII_n_CH_k_SCRATCH_0_SEID is currently defined as GENMASK(2, 0), only
3 bits wide. Serial engine indices >= 8 get silently truncated by
FIELD_PREP()/u32_encode_bits() when written into the scratch register,
causing the GPI channel to bind to the wrong serial engine. The
channel allocate command still succeeds (it doesn't require the
target SE to respond), but the subsequent channel start command times
out waiting for hardware to complete the handoff to the (incorrectly
bound) SE, and gpi_send_cmd() returns -EIO leading to GSI usecase failures
for SE8 and SE9 serial engines.

Older documentation, such as the SDM845 hardware programming guide,
describes the SE ID field as bits [2:0]. More recent QUP hardware
documentation defines the field as bits [3:0]. Use the wider definition
to match current hardware documentation while remaining compatible with
existing platforms and enabling serial engine IDs greater than 7.

Also update the SE Protocol field definition to match the documented
register layout and keep both fields correctly packed.

Fixes: 5d0c3533a19f ("dmaengine: qcom: Add GPI dma driver")
Signed-off-by: Chandana Kishori Chiluveru <chandana.chiluveru@oss.qualcomm.com>
---
 drivers/dma/qcom/gpi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c
index a5055a6273af..8f09eaf4e714 100644
--- a/drivers/dma/qcom/gpi.c
+++ b/drivers/dma/qcom/gpi.c
@@ -207,8 +207,8 @@ enum CNTXT_OFFS {
 
 /* Scratch registers */
 #define GPII_n_CH_k_SCRATCH_0_OFFS(n, k)	(0x20060 + (0x4000 * (n)) + (0x80 * (k)))
-#define GPII_n_CH_k_SCRATCH_0_SEID		GENMASK(2, 0)
-#define GPII_n_CH_k_SCRATCH_0_PROTO		GENMASK(7, 4)
+#define GPII_n_CH_k_SCRATCH_0_SEID		GENMASK(3, 0)
+#define GPII_n_CH_k_SCRATCH_0_PROTO		GENMASK(6, 4)
 #define GPII_n_CH_k_SCRATCH_0_PAIR		GENMASK(20, 16)
 #define GPII_n_CH_k_SCRATCH_0(pair, proto, seid)		\
 			     (FIELD_PREP(GPII_n_CH_k_SCRATCH_0_PAIR, pair)	| \

---
base-commit: 34cf6dafc47441dfb6b356a095b89c3585a93714
change-id: 20260710-fix_se_id_and_se_protocol_fields-d7f0fe616596

Best regards,
--  
Chandana Kishori Chiluveru <chandana.chiluveru@oss.qualcomm.com>


             reply	other threads:[~2026-07-20 15:28 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-20 15:27 Chandana Kishori Chiluveru [this message]
2026-07-20 15:47 ` Konrad Dybcio
2026-07-21 11:11   ` Chandana Kishori Chiluveru

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260720-fix_se_id_and_se_protocol_fields-v1-1-e41dbb107d97@oss.qualcomm.com \
    --to=chandana.chiluveru@oss.qualcomm.com \
    --cc=Frank.Li@kernel.org \
    --cc=bjorn.andersson@oss.qualcomm.com \
    --cc=dmaengine@vger.kernel.org \
    --cc=konrad.dybcio@oss.qualcomm.com \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mukesh.savaliya@oss.qualcomm.com \
    --cc=praveen.talari@oss.qualcomm.com \
    --cc=vkoul@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®