On 09/08/2018 12:22 PM, Chen-Yu Tsai wrote: > On Sat, Sep 8, 2018 at 6:06 PM Hans Verkuil <hverkuil@xxxxxxxxx> wrote: >> >> On 09/07/2018 06:33 PM, Paul Kocialkowski wrote: >>> This brings the requested modifications on top of version 9 of the >>> Cedrus VPU driver, that implements stateless video decoding using the >>> Request API. >>> >>> Paul Kocialkowski (2): >>> media: cedrus: Fix error reporting in request validation >>> media: cedrus: Add TODO file with tasks to complete before unstaging >>> >>> drivers/staging/media/sunxi/cedrus/TODO | 7 +++++++ >>> drivers/staging/media/sunxi/cedrus/cedrus.c | 15 ++++++++++++--- >>> 2 files changed, 19 insertions(+), 3 deletions(-) >>> create mode 100644 drivers/staging/media/sunxi/cedrus/TODO >>> >> >> So close... >> >> When compiling under e.g. intel I get errors since it doesn't know about >> the sunxi_sram_claim/release function and the PHYS_PFN_OFFSET define. >> >> Is it possible to add stub functions to linux/soc/sunxi/sunxi_sram.h >> if CONFIG_SUNXI_SRAM is not defined? That would be the best fix for that. >> >> The use of PHYS_PFN_OFFSET is weird: are you sure this is the right >> way? I see that drivers/of/device.c also sets dev->dma_pfn_offset, which >> makes me wonder if this information shouldn't come from the device tree. >> >> You are the only driver that uses this define directly, which makes me >> suspicious. > > On Allwinner platforms, some devices do DMA directly on the memory BUS > with the DRAM controller. In such cases, the DRAM has no offset. In all > other cases where the DMA goes through the common system bus and the DRAM > offset is either 0x40000000 or 0x20000000, depending on the SoC. Since the > former case is not described in the device tree (this is being worked on > by Maxime BTW), the dma_pfn_offset is not the value it should be. AFAIK > only the display and media subsystems (VPU, camera, TS) are wired this > way. > > In drivers/gpu/drm/sun4i/sun4i_backend.c (the display driver) we use > PHYS_OFFSET, which is pretty much the same thing. > OK, in that case just put #ifdef PHYS_PFN_OFFSET around that line together with a comment that this will eventually come from the device tree. Regards, Hans
