From: Sinan Kaya <okaya@codeaurora.org> To: Christoffer Dall <christoffer.dall@linaro.org> Cc: dmaengine@vger.kernel.org, marc.zyngier@arm.com, mark.rutland@arm.com, timur@codeaurora.org, devicetree@vger.kernel.org, cov@codeaurora.org, vinod.koul@intel.com, jcm@redhat.com, vikrams@codeaurora.org, arnd@arndb.de, eric.auger@linaro.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, agross@codeaurora.org, shankerd@codeaurora.org Subject: Re: [PATCH V14 0/9] dma: add Qualcomm Technologies HIDMA driver Date: Mon, 8 Feb 2016 09:24:39 -0500 [thread overview] Message-ID: <56B8A527.7010206@codeaurora.org> (raw) In-Reply-To: <20160208101432.GA1150@cbox> Hi, On 2/8/2016 5:14 AM, Christoffer Dall wrote: > Hi Sinan, > > On Thu, Feb 04, 2016 at 11:34:31PM -0500, Sinan Kaya wrote: >> The Qualcomm Technologies HIDMA device has been designed >> to support virtualization technology. The driver has been >> divided into two to follow the hardware design. >> >> 1. HIDMA Management driver >> 2. HIDMA Channel driver >> >> Each HIDMA HW consists of multiple channels. These channels >> share some set of common parameters. These parameters are >> initialized by the management driver during power up. >> Same management driver is used for monitoring the execution >> of the channels. Management driver can change the performance >> behavior dynamically such as bandwidth allocation and >> prioritization in the future. >> >> The management driver is executed in host context and >> is the main management entity for all channels provided by >> the device. > > I'm not at all familiar with this kind of hardware. > Let me help. > Once an entity (userspace or VM) has a HIDAM channel assigned via VFIO, > how does it use it? HIDMA is a HW accelerator for memory operations like memcpy and memset. It fits into the DMA engine framework. There are two classes of DMA HW. These are slave DMA and standalone DMA. Slave DMA is generally related to another piece of HW that needs DMA for moving data. Standalone DMA is intended for OS/CPU consumption not HW. These can be used to offload crypto operations (XOR) or other memory transactions (memcpy and memset) that are lengthy. Once the HIDMA channel is assigned to the guest machine, guest operating system uses the DMA channel to offload memory operations as HIDMA only supports memcpy. IOMMU HW provides the isolation from the rest of the host kernel or from other guest machines. > Is it used in relation with another device to > perform DMA on its behalf or is a HIDMA channel something that's useful > on its own? It is standalone only. The relationship you are referring to is known as slave DMA engine. HIDMA does not support slave DMA. HIDMA only supports memcpy and memset in HW and only memcpy in SW as the memset support has been removed from the kernel long time ago. > > Thanks, > -Christoffer > -- Sinan Kaya Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
WARNING: multiple messages have this Message-ID (diff)
From: okaya@codeaurora.org (Sinan Kaya) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH V14 0/9] dma: add Qualcomm Technologies HIDMA driver Date: Mon, 8 Feb 2016 09:24:39 -0500 [thread overview] Message-ID: <56B8A527.7010206@codeaurora.org> (raw) In-Reply-To: <20160208101432.GA1150@cbox> Hi, On 2/8/2016 5:14 AM, Christoffer Dall wrote: > Hi Sinan, > > On Thu, Feb 04, 2016 at 11:34:31PM -0500, Sinan Kaya wrote: >> The Qualcomm Technologies HIDMA device has been designed >> to support virtualization technology. The driver has been >> divided into two to follow the hardware design. >> >> 1. HIDMA Management driver >> 2. HIDMA Channel driver >> >> Each HIDMA HW consists of multiple channels. These channels >> share some set of common parameters. These parameters are >> initialized by the management driver during power up. >> Same management driver is used for monitoring the execution >> of the channels. Management driver can change the performance >> behavior dynamically such as bandwidth allocation and >> prioritization in the future. >> >> The management driver is executed in host context and >> is the main management entity for all channels provided by >> the device. > > I'm not at all familiar with this kind of hardware. > Let me help. > Once an entity (userspace or VM) has a HIDAM channel assigned via VFIO, > how does it use it? HIDMA is a HW accelerator for memory operations like memcpy and memset. It fits into the DMA engine framework. There are two classes of DMA HW. These are slave DMA and standalone DMA. Slave DMA is generally related to another piece of HW that needs DMA for moving data. Standalone DMA is intended for OS/CPU consumption not HW. These can be used to offload crypto operations (XOR) or other memory transactions (memcpy and memset) that are lengthy. Once the HIDMA channel is assigned to the guest machine, guest operating system uses the DMA channel to offload memory operations as HIDMA only supports memcpy. IOMMU HW provides the isolation from the rest of the host kernel or from other guest machines. > Is it used in relation with another device to > perform DMA on its behalf or is a HIDMA channel something that's useful > on its own? It is standalone only. The relationship you are referring to is known as slave DMA engine. HIDMA does not support slave DMA. HIDMA only supports memcpy and memset in HW and only memcpy in SW as the memset support has been removed from the kernel long time ago. > > Thanks, > -Christoffer > -- Sinan Kaya Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
next prev parent reply other threads:[~2016-02-08 14:24 UTC|newest] Thread overview: 100+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-02-05 4:34 [PATCH V14 0/9] dma: add Qualcomm Technologies HIDMA driver Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-02-05 4:34 ` [PATCH V14 1/9] dma: qcom_bam_dma: move to qcom directory Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-03-11 2:13 ` Vinod Koul 2016-03-11 2:13 ` Vinod Koul 2016-02-05 4:34 ` [PATCH V14 2/9] dma: hidma: Add Device Tree binding Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-03-11 2:16 ` Vinod Koul 2016-03-11 2:16 ` Vinod Koul 2016-02-05 4:34 ` [PATCH V14 3/9] dma: add Qualcomm Technologies HIDMA management driver Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-03-11 2:16 ` Vinod Koul 2016-03-11 2:16 ` Vinod Koul 2016-02-05 4:34 ` [PATCH V14 4/9] dma: add Qualcomm Technologies HIDMA channel driver Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya [not found] ` <1454646882-24369-5-git-send-email-okaya-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> 2016-03-11 2:17 ` Vinod Koul 2016-03-11 2:17 ` Vinod Koul 2016-03-11 2:17 ` Vinod Koul 2016-02-05 4:34 ` [PATCH V14 5/9] dma: qcom_hidma: implement lower level hardware interface Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-03-11 2:06 ` Vinod Koul 2016-03-11 2:06 ` Vinod Koul 2016-03-11 3:08 ` Okaya-sgV2jX0FEOL9JmXXK+q4OQ 2016-03-11 3:08 ` Okaya at codeaurora.org 2016-03-11 3:08 ` Okaya 2016-03-11 16:02 ` Sinan Kaya 2016-03-11 16:02 ` Sinan Kaya [not found] ` <56E2EC1C.6040107-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> 2016-03-11 16:32 ` Vinod Koul 2016-03-11 16:32 ` Vinod Koul 2016-03-11 16:32 ` Vinod Koul 2016-03-11 16:44 ` Sinan Kaya 2016-03-11 16:44 ` Sinan Kaya 2016-03-11 19:29 ` Sinan Kaya 2016-03-11 19:29 ` Sinan Kaya 2016-03-11 21:59 ` Sinan Kaya 2016-03-11 21:59 ` Sinan Kaya 2016-03-13 16:00 ` Vinod Koul 2016-03-13 16:00 ` Vinod Koul 2016-03-14 13:53 ` Sinan Kaya 2016-03-14 13:53 ` Sinan Kaya 2016-03-13 15:59 ` Vinod Koul 2016-03-13 15:59 ` Vinod Koul 2016-03-14 13:56 ` Sinan Kaya 2016-03-14 13:56 ` Sinan Kaya 2016-02-05 4:34 ` [PATCH V14 6/9] dma: qcom_hidma: add debugfs hooks Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-02-05 4:34 ` [PATCH V14 7/9] dma: qcom_hidma: add support for object hierarchy Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-02-05 4:34 ` [PATCH V14 8/9] vfio, platform: add support for ACPI while detecting the reset driver Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya [not found] ` <1454646882-24369-9-git-send-email-okaya-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> 2016-02-26 16:24 ` Sinan Kaya 2016-02-26 16:24 ` Sinan Kaya 2016-02-26 16:24 ` Sinan Kaya 2016-02-26 17:15 ` Eric Auger 2016-02-26 17:15 ` Eric Auger 2016-02-26 17:15 ` Eric Auger 2016-02-26 19:21 ` Sinan Kaya 2016-02-26 19:21 ` Sinan Kaya 2016-03-02 18:34 ` Sinan Kaya 2016-03-02 18:34 ` Sinan Kaya 2016-03-03 23:14 ` Eric Auger 2016-03-03 23:14 ` Eric Auger 2016-03-04 5:20 ` Sinan Kaya 2016-03-04 5:20 ` Sinan Kaya 2016-03-07 4:09 ` Eric Auger 2016-03-07 4:09 ` Eric Auger [not found] ` <56DCFEE0.6080101-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> 2016-03-07 15:30 ` Sinan Kaya 2016-03-07 15:30 ` Sinan Kaya 2016-03-07 15:30 ` Sinan Kaya 2016-03-08 4:46 ` Eric Auger 2016-03-08 4:46 ` Eric Auger 2016-03-08 5:07 ` Sinan Kaya 2016-03-08 5:07 ` Sinan Kaya 2016-03-08 15:44 ` Sinan Kaya 2016-03-08 15:44 ` Sinan Kaya 2016-02-05 4:34 ` [PATCH V14 9/9] vfio, platform: add QTI HIDMA " Sinan Kaya 2016-02-05 4:34 ` Sinan Kaya 2016-02-26 17:52 ` Eric Auger 2016-02-26 17:52 ` Eric Auger 2016-02-26 19:05 ` Sinan Kaya 2016-02-26 19:05 ` Sinan Kaya 2016-02-08 10:14 ` [PATCH V14 0/9] dma: add Qualcomm Technologies HIDMA driver Christoffer Dall 2016-02-08 10:14 ` Christoffer Dall 2016-02-08 14:24 ` Sinan Kaya [this message] 2016-02-08 14:24 ` Sinan Kaya 2016-02-08 17:00 ` Christoffer Dall 2016-02-08 17:00 ` Christoffer Dall 2016-02-26 16:21 ` Sinan Kaya 2016-02-26 16:21 ` Sinan Kaya 2016-02-26 16:52 ` Timur Tabi 2016-02-26 16:52 ` Timur Tabi 2016-03-02 18:40 ` Sinan Kaya 2016-03-02 18:40 ` Sinan Kaya [not found] ` <56D733BA.6030203-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> 2016-03-03 3:44 ` Vinod Koul 2016-03-03 3:44 ` Vinod Koul 2016-03-03 3:44 ` Vinod Koul 2016-03-03 15:22 ` Sinan Kaya 2016-03-03 15:22 ` Sinan Kaya
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=56B8A527.7010206@codeaurora.org \ --to=okaya@codeaurora.org \ --cc=agross@codeaurora.org \ --cc=arnd@arndb.de \ --cc=christoffer.dall@linaro.org \ --cc=cov@codeaurora.org \ --cc=devicetree@vger.kernel.org \ --cc=dmaengine@vger.kernel.org \ --cc=eric.auger@linaro.org \ --cc=jcm@redhat.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-arm-msm@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=marc.zyngier@arm.com \ --cc=mark.rutland@arm.com \ --cc=shankerd@codeaurora.org \ --cc=timur@codeaurora.org \ --cc=vikrams@codeaurora.org \ --cc=vinod.koul@intel.com \ /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: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.