linux-kernel - Re: [RESEND PATCH v3 0/6] STM32 DMA-MDMA chaining feature

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <YxTd1jBS3xk/YT6m@matsya>
Date:   Sun, 4 Sep 2022 22:48:14 +0530
From:   Vinod Koul <vkoul@...nel.org>
To:     Amelie Delaunay <amelie.delaunay@...s.st.com>
Cc:     Jonathan Corbet <corbet@....net>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        Alexandre Torgue <alexandre.torgue@...s.st.com>,
        linux-doc@...r.kernel.org, dmaengine@...r.kernel.org,
        linux-stm32@...md-mailman.stormreply.com,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Marek Vasut <marex@...x.de>
Subject: Re: [RESEND PATCH v3 0/6] STM32 DMA-MDMA chaining feature

On 29-08-22, 17:46, Amelie Delaunay wrote:
> This patchset (re)introduces STM32 DMA-MDMA chaining feature.
> 
> As the DMA is not able to generate convenient burst transfer on the DDR,
> it penalises the AXI bus when accessing the DDR. While it accesses
> optimally the SRAM. The DMA-MDMA chaining then consists in having an SRAM
> buffer between DMA and MDMA, so the DMA deals with peripheral and SRAM,
> and the MDMA with SRAM and DDR.
> 
> The feature relies on the fact that DMA channel Transfer Complete signal
> can trigger a MDMA channel transfer and MDMA can clear the DMA request by
> writing to DMA Interrupt Clear register.
> 
> A deeper introduction can be found in patch 1.
> 
> Previous implementation [1] has been dropped as nacked.
> Unlike this previous implementation (where all the stuff was embedded in
> stm32-dma driver), the user (in peripheral drivers using dma) has now to
> configure the MDMA channel.

Applied, thanks

-- 
~Vinod