linux-kernel - Re: [PATCH v8 2/2] i2c: i2c-qcom-geni: Add Block event interrupt support

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Message-ID: <aPDiXIMcdM-Gm_J3@vaman>
Date: Thu, 16 Oct 2025 17:47:32 +0530
From: Vinod Koul <vkoul@...nel.org>
To: Andi Shyti <andi.shyti@...nel.org>
Cc: Jyothi Kumar Seerapu <jyothi.seerapu@....qualcomm.com>,
	Mukesh Kumar Savaliya <quic_msavaliy@...cinc.com>,
	Viken Dadhaniya <quic_vdadhani@...cinc.com>,
	Sumit Semwal <sumit.semwal@...aro.org>,
	Christian König <christian.koenig@....com>,
	linux-arm-msm@...r.kernel.org, dmaengine@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-i2c@...r.kernel.org,
	linux-media@...r.kernel.org, dri-devel@...ts.freedesktop.org,
	linaro-mm-sig@...ts.linaro.org, quic_vtanuku@...cinc.com
Subject: Re: [PATCH v8 2/2] i2c: i2c-qcom-geni: Add Block event interrupt
 support

On 03-10-25, 20:50, Andi Shyti wrote:
> On Thu, Sep 25, 2025 at 05:30:35PM +0530, Jyothi Kumar Seerapu wrote:
> > From: Jyothi Kumar Seerapu <quic_jseerapu@...cinc.com>
> > 
> > The I2C driver gets an interrupt upon transfer completion.
> > When handling multiple messages in a single transfer, this
> > results in N interrupts for N messages, leading to significant
> > software interrupt latency.
> > 
> > To mitigate this latency, utilize Block Event Interrupt (BEI)
> > mechanism. Enabling BEI instructs the hardware to prevent interrupt
> > generation and BEI is disabled when an interrupt is necessary.
> > 
> > Large I2C transfer can be divided into chunks of messages internally.
> > Interrupts are not expected for the messages for which BEI bit set,
> > only the last message triggers an interrupt, indicating the completion of
> > N messages. This BEI mechanism enhances overall transfer efficiency.
> > 
> > BEI optimizations are currently implemented for I2C write transfers only,
> > as there is no use case for multiple I2C read messages in a single transfer
> > at this time.
> > 
> > Signed-off-by: Jyothi Kumar Seerapu <quic_jseerapu@...cinc.com>
> 
> Because this series is touching multiple subsystems, I'm going to
> ack it:
> 
> Acked-by: Andi Shyti <andi.shyti@...nel.org>
> 
> We are waiting for someone from DMA to ack it (Vinod or Sinan).

Thanks, I will pick it with your ack

-- 
~Vinod