From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas Kandagatla Subject: Re: [PATCH 0/4] dmaengine: qcom: bam_dma: fixes for remotely controlled bam Date: Wed, 17 Jan 2018 10:55:34 +0000 Message-ID: References: <20180116190236.14558-1-srinivas.kandagatla@linaro.org> <20180117101835.GM18649@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180117101835.GM18649@localhost> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Vinod Koul Cc: Andy Gross , dmaengine@vger.kernel.org, Rob Herring , Mark Rutland , David Brown , Dan Williams , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, yanhe@quicinc.com, ramkri@qti.qualcomm.com, sdharia@quicinc.com List-Id: devicetree@vger.kernel.org On 17/01/18 10:18, Vinod Koul wrote: > On Tue, Jan 16, 2018 at 07:02:32PM +0000, srinivas.kandagatla@linaro.org wrote: >> From: Srinivas Kandagatla >> >> Hi Andy, >> >> I did hit few issues while trying out SLIMBus BAM on DB820c, this BAM instance >> is remotely controlled and powered up after ADSP is booted using QMI commands. > > What do you mean by "remotely controlled" in this series? DMA controller is controlled by the remote processor, which is a DSP in this case. Linux side is in remote mode in this setup, this can setup transfer descriptors and start/stop a transfer. But all the initialization/powerup part will be done in the remote processor. --srini > >> >> Firstly some of the master registers are written even when the BAM is remotely >> controlled, and secondly reading registers when bam is not ready yet. >> >> These 4 patches address these issues, there are few more issues like doing PM >> in simillar usecase, these will be addressed soon. >> >> Thanks, >> Srini >> >> Srinivas Kandagatla (4): >> dmaengine: qcom: bam_dma: make bam clk optional >> dmaengine: qcom: bam_dma: add num-channels binding for remotely >> controlled >> dmaengine: qcom: bam_dma: do not write to global regs in remote mode >> dmaengine: qcom: bam_dma: Add num-ees dt binding for remotely >> controlled >> >> .../devicetree/bindings/dma/qcom_bam_dma.txt | 4 ++ >> drivers/dma/qcom/bam_dma.c | 56 +++++++++++++++------- >> 2 files changed, 43 insertions(+), 17 deletions(-) >> >> -- >> 2.15.1 >> >