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

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Message-ID: <3lgris6k6ewqjdcfmmovygstqrqjx2jidtr3hb3v47gpgadkka@wlua7qpd7ahf>
Date: Fri, 3 Oct 2025 20:50:04 +0200
From: Andi Shyti <andi.shyti@...nel.org>
To: Jyothi Kumar Seerapu <jyothi.seerapu@....qualcomm.com>
Cc: Vinod Koul <vkoul@...nel.org>, 
	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 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,
Andi