From: Arnd Bergmann <arnd@arndb.de> To: Boris BREZILLON <boris.brezillon@free-electrons.com> Cc: Mark yao <mark.yao@rock-chips.com>, heiko@sntech.de, David Airlie <airlied@gmail.com>, Rob Clark <robdclark@gmail.com>, Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>, Mark Rutland <mark.rutland@arm.com>, Ian Campbell <ijc+devicetree@hellion.org.uk>, Kumar Gala <galak@codeaurora.org>, Randy Dunlap <rdunlap@infradead.org>, Grant Likely <grant.likely@linaro.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, John Stultz <john.stultz@linaro.org>, Rom Lemarchand <romlem@google.com>, devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-api@vger.kernel.org, linux-rockchip@lists.infradead.org, dianders@chromium.org, marcheu@chromium.org, dbehr@chromium.org, olof@lixom.net, djkurtz@chromium.org, xjq@rock-chips.com, kfx@rock-chips.com, cym@rock-chips.com, cf@rock-chips.com, zyw@rock-chips.com, xxm@rock-chips.com, huangtao@rock-chips.com, kever.yang@rock-chips.com, yxj@rock-chips.com, wxt@rock-chips.com, xw@rock-chips.com Subject: Re: [PATCH v4 1/5] drm/rockchip: Add basic drm driver Date: Mon, 22 Sep 2014 17:54:42 +0200 [thread overview] Message-ID: <3102396.6rAQmqkXXM@wuerfel> (raw) In-Reply-To: <20140922171506.31d59a76@bbrezillon> On Monday 22 September 2014 17:15:06 Boris BREZILLON wrote: > > > + > > > + /* TODO(djkurtz): fetch the mapping start/size from somewhere */ > > > + mapping = arm_iommu_create_mapping(&platform_bus_type, 0x10000000, > > > + SZ_1G); > > > + if (IS_ERR(mapping)) { > > > + ret = PTR_ERR(mapping); > > > + goto err_config_cleanup; > > > + } > > > + > > > + dma_set_coherent_mask(dev, DMA_BIT_MASK(32)); > > > > This is the default coherent mask. If you call this function, you > > should normally check the return value, or call dma_set_mask first, > > which you apparently don't do here, and in another place in this > > patch. > > By "This is the default mask" do you mean it shouldn't be called at > all ? Cause I ran into some trouble when not calling this in my > atmel-hlcdc driver. We used to get this wrong in the of_platform code, but it should work now. > Actually, in my case the platform device is created by the MFD core > which seems to let the coherent_dma_mask uninitialized. That may well be different, but it seems like a good idea to allow the MFD core to set this up as well. In general, we expect that devices that are capable of doing DMA start with a 32-bit mask for both dma_mask and dma_coherent_mask, and a driver that requires a smaller masks or wants a larger mask has to call the appropriate interface to set these, and check the return value. Arnd
WARNING: multiple messages have this Message-ID (diff)
From: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org> To: Boris BREZILLON <boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> Cc: Mark yao <mark.yao-TNX95d0MmH7DzftRWevZcw@public.gmane.org>, heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org, David Airlie <airlied-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Rob Clark <robdclark-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>, Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>, Ian Campbell <ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org>, Kumar Gala <galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>, Randy Dunlap <rdunlap-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>, John Stultz <john.stultz-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Rom Lemarchand <romlem-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, marcheu-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, dbehr-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, olof-nZhT3qVonbNeoWH0uzbU5w@public.gmane.org, djkurtz-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, xjq-TNX95d0MmH7DzftRWevZcw@public.gmane.org, kfx-TNX95d0MmH7DzftRWevZcw@public.gmane.org, cym-TNX95d0MmH7DzftRWevZcw@public.gmane.org, cf-TNX95d0MmH7DzftRWevZcw@public.gmane.org, zyw@rock- Subject: Re: [PATCH v4 1/5] drm/rockchip: Add basic drm driver Date: Mon, 22 Sep 2014 17:54:42 +0200 [thread overview] Message-ID: <3102396.6rAQmqkXXM@wuerfel> (raw) In-Reply-To: <20140922171506.31d59a76@bbrezillon> On Monday 22 September 2014 17:15:06 Boris BREZILLON wrote: > > > + > > > + /* TODO(djkurtz): fetch the mapping start/size from somewhere */ > > > + mapping = arm_iommu_create_mapping(&platform_bus_type, 0x10000000, > > > + SZ_1G); > > > + if (IS_ERR(mapping)) { > > > + ret = PTR_ERR(mapping); > > > + goto err_config_cleanup; > > > + } > > > + > > > + dma_set_coherent_mask(dev, DMA_BIT_MASK(32)); > > > > This is the default coherent mask. If you call this function, you > > should normally check the return value, or call dma_set_mask first, > > which you apparently don't do here, and in another place in this > > patch. > > By "This is the default mask" do you mean it shouldn't be called at > all ? Cause I ran into some trouble when not calling this in my > atmel-hlcdc driver. We used to get this wrong in the of_platform code, but it should work now. > Actually, in my case the platform device is created by the MFD core > which seems to let the coherent_dma_mask uninitialized. That may well be different, but it seems like a good idea to allow the MFD core to set this up as well. In general, we expect that devices that are capable of doing DMA start with a 32-bit mask for both dma_mask and dma_coherent_mask, and a driver that requires a smaller masks or wants a larger mask has to call the appropriate interface to set these, and check the return value. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2014-09-22 15:55 UTC|newest] Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top 2014-09-22 10:47 [PATCH v4 0/5] Add drm driver for Rockchip Socs Mark yao 2014-09-22 10:47 ` Mark yao 2014-09-22 10:48 ` [PATCH v4 1/5] drm/rockchip: Add basic drm driver Mark yao 2014-09-22 13:24 ` Boris BREZILLON 2014-09-22 13:24 ` Boris BREZILLON 2014-09-23 5:59 ` Mark yao 2014-09-23 5:59 ` Mark yao 2014-09-22 14:43 ` Arnd Bergmann 2014-09-22 14:43 ` Arnd Bergmann 2014-09-22 15:15 ` Boris BREZILLON 2014-09-22 15:15 ` Boris BREZILLON 2014-09-22 15:54 ` Arnd Bergmann [this message] 2014-09-22 15:54 ` Arnd Bergmann 2014-09-23 7:09 ` Mark yao 2014-09-23 7:09 ` Mark yao 2014-09-23 8:11 ` Arnd Bergmann 2014-09-23 8:11 ` Arnd Bergmann 2014-09-23 7:05 ` Mark yao 2014-09-23 7:05 ` Mark yao 2014-09-22 19:10 ` Rob Clark 2014-09-22 19:10 ` Rob Clark 2014-09-23 6:50 ` Mark yao 2014-09-23 6:50 ` Mark yao 2014-09-24 8:20 ` Daniel Vetter 2014-09-24 8:20 ` Daniel Vetter 2014-09-24 9:31 ` Mark yao 2014-09-24 9:31 ` Mark yao 2014-09-24 11:20 ` Daniel Vetter 2014-09-24 11:20 ` Daniel Vetter 2014-09-25 0:54 ` Mark yao 2014-09-25 19:30 ` Daniel Vetter 2014-09-25 19:30 ` Daniel Vetter 2014-09-22 10:50 ` [PATCH v4 2/5] dt-bindings: video: Add for rockchip display subsytem Mark yao 2014-09-22 10:57 ` [PATCH v4 3/5] dt-bindings: video: Add documentation for rockchip vop Mark yao 2014-09-22 10:57 ` Mark yao 2014-09-22 10:58 ` [PATCH v4 4/5] dt-bindings: video: Add documentation for rockchip edp Mark yao 2014-09-22 10:58 ` Mark yao 2014-09-22 11:02 ` [PATCH v4 5/5] drm/rockchip: Add support for Rockchip Soc EDP Mark yao 2014-09-22 11:02 ` Mark yao 2014-09-22 19:20 ` Rob Clark 2014-09-22 19:20 ` Rob Clark 2014-09-23 8:47 ` cym 2014-09-23 8:47 ` cym 2014-09-23 13:56 ` Rob Clark 2014-09-23 13:56 ` Rob Clark 2014-09-23 23:35 ` Rob Clark 2014-09-23 23:35 ` Rob Clark 2014-09-24 10:30 ` jeff chen 2014-09-24 10:30 ` jeff chen
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=3102396.6rAQmqkXXM@wuerfel \ --to=arnd@arndb.de \ --cc=airlied@gmail.com \ --cc=boris.brezillon@free-electrons.com \ --cc=cf@rock-chips.com \ --cc=cym@rock-chips.com \ --cc=dbehr@chromium.org \ --cc=devicetree@vger.kernel.org \ --cc=dianders@chromium.org \ --cc=djkurtz@chromium.org \ --cc=dri-devel@lists.freedesktop.org \ --cc=galak@codeaurora.org \ --cc=grant.likely@linaro.org \ --cc=gregkh@linuxfoundation.org \ --cc=heiko@sntech.de \ --cc=huangtao@rock-chips.com \ --cc=ijc+devicetree@hellion.org.uk \ --cc=john.stultz@linaro.org \ --cc=kever.yang@rock-chips.com \ --cc=kfx@rock-chips.com \ --cc=linux-api@vger.kernel.org \ --cc=linux-doc@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-rockchip@lists.infradead.org \ --cc=marcheu@chromium.org \ --cc=mark.rutland@arm.com \ --cc=mark.yao@rock-chips.com \ --cc=olof@lixom.net \ --cc=pawel.moll@arm.com \ --cc=rdunlap@infradead.org \ --cc=robdclark@gmail.com \ --cc=robh+dt@kernel.org \ --cc=romlem@google.com \ --cc=wxt@rock-chips.com \ --cc=xjq@rock-chips.com \ --cc=xw@rock-chips.com \ --cc=xxm@rock-chips.com \ --cc=yxj@rock-chips.com \ --cc=zyw@rock-chips.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.