Hi Conor, Nathan, On Wed 07 Dec 22, 10:06, Conor Dooley wrote: > On Sun, Nov 27, 2022 at 11:31:41PM -0700, Nathan Chancellor wrote: > > Hi Paul, > > > > On Thu, Nov 03, 2022 at 05:37:14PM +0100, Paul Kocialkowski wrote: > > > Some Allwinner platforms come with an Image Signal Processor, which > > > supports various features in order to enhance and transform data > > > received by image sensors into good-looking pictures. In most cases, > > > the data is raw bayer, which gets internally converted to RGB and > > > finally YUV, which is what the hardware produces. > > > > > > This driver supports ISPs that are similar to the A31 ISP, which was > > > the first standalone ISP found in Allwinner platforms. Simpler ISP > > > blocks were found in the A10 and A20, where they are tied to a CSI > > > controller. Newer generations of Allwinner SoCs (starting with the > > > H6, H616, etc) come with a new camera subsystem and revised ISP. > > > Even though these previous and next-generation ISPs are somewhat > > > similar to the A31 ISP, they have enough significant differences to > > > be out of the scope of this driver. > > > > > > While the ISP supports many features, including 3A and many > > > enhancement blocks, this implementation is limited to the following: > > > - V3s (V3/S3) platform support; > > > - Bayer media bus formats as input; > > > - Semi-planar YUV (NV12/NV21) as output; > > > - Debayering with per-component gain and offset configuration; > > > - 2D noise filtering with configurable coefficients. > > > > > > Since many features are missing from the associated uAPI, the driver > > > is aimed to integrate staging until all features are properly > > > described. > > > > > > On the technical side, it uses the v4l2 and media controller APIs, > > > with a video node for capture, a processor subdev and a video node > > > for parameters submission. A specific uAPI structure and associated > > > v4l2 meta format are used to configure parameters of the supported > > > modules. > > > > > > One particular thing about the hardware is that configuration for > > > module registers needs to be stored in a DMA buffer and gets copied > > > to actual registers by the hardware at the next vsync, when instructed > > > by a flag. This is handled by the "state" mechanism in the driver. > > > > > > Signed-off-by: Paul Kocialkowski > > > > This patch is now in -next as commit e3185e1d7c14 ("media: staging: > > media: Add support for the Allwinner A31 ISP"), where it causes the > > following clang warnings: > > FWIW, this is (as yet) unfixed & thus breaking allmodconfig w/ clang. > I had a quick look on lore but could not see a proposed fix other than > what Nathan has pasted below. Sorry for the inconvenience. I've just sent a fix series which should resolve these issues (and other ones too): "Allwinner A31/A83T CSI/ISP/MIPI CSI-2 media fixes" (version 2). Thanks for the report! Paul > > > +void sun6i_isp_capture_configure(struct sun6i_isp_device *isp_dev) > > > +{ > > > + unsigned int width, height; > > > + unsigned int stride_luma, stride_chroma = 0; > > > + unsigned int stride_luma_div4, stride_chroma_div4; > > > + const struct sun6i_isp_capture_format *format; > > > + const struct v4l2_format_info *info; > > > + u32 pixelformat; > > > + > > > + sun6i_isp_capture_dimensions(isp_dev, &width, &height); > > > + sun6i_isp_capture_format(isp_dev, &pixelformat); > > > + > > > + format = sun6i_isp_capture_format_find(pixelformat); > > > + if (WARN_ON(!format)) > > > + return; > > > + > > > + sun6i_isp_load_write(isp_dev, SUN6I_ISP_MCH_SIZE_CFG_REG, > > > + SUN6I_ISP_MCH_SIZE_CFG_WIDTH(width) | > > > + SUN6I_ISP_MCH_SIZE_CFG_HEIGHT(height)); > > > + > > > + info = v4l2_format_info(pixelformat); > > > + if (WARN_ON(!info)) > > > + return; > > > + > > > + stride_luma = width * info->bpp[0]; > > > + stride_luma_div4 = DIV_ROUND_UP(stride_luma, 4); > > > + > > > + if (info->comp_planes > 1) { > > > + stride_chroma = width * info->bpp[1] / info->hdiv; > > > + stride_chroma_div4 = DIV_ROUND_UP(stride_chroma, 4); > > > + } > > > + > > > + sun6i_isp_load_write(isp_dev, SUN6I_ISP_MCH_CFG_REG, > > > + SUN6I_ISP_MCH_CFG_EN | > > > + SUN6I_ISP_MCH_CFG_OUTPUT_FMT(format->output_format) | > > > + SUN6I_ISP_MCH_CFG_STRIDE_Y_DIV4(stride_luma_div4) | > > > + SUN6I_ISP_MCH_CFG_STRIDE_UV_DIV4(stride_chroma_div4)); > > > +} > > > > > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c:135:6: error: variable 'stride_chroma_div4' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized] > > if (info->comp_planes > 1) { > > ^~~~~~~~~~~~~~~~~~~~~ > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c:144:42: note: uninitialized use occurs here > > SUN6I_ISP_MCH_CFG_STRIDE_UV_DIV4(stride_chroma_div4)); > > ^~~~~~~~~~~~~~~~~~ > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_reg.h:249:48: note: expanded from macro 'SUN6I_ISP_MCH_CFG_STRIDE_UV_DIV4' > > #define SUN6I_ISP_MCH_CFG_STRIDE_UV_DIV4(v) (((v) << 20) & GENMASK(30, 20)) > > ^ > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c:135:2: note: remove the 'if' if its condition is always true > > if (info->comp_planes > 1) { > > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c:112:51: note: initialize the variable 'stride_chroma_div4' to silence this warning > > unsigned int stride_luma_div4, stride_chroma_div4; > > ^ > > = 0 > > > > Does stride_chroma_div4 want to just be initialized to zero? > > > > > +static int sun6i_isp_proc_notifier_bound(struct v4l2_async_notifier *notifier, > > > + struct v4l2_subdev *remote_subdev, > > > + struct v4l2_async_subdev *async_subdev) > > > +{ > > > + struct sun6i_isp_device *isp_dev = > > > + container_of(notifier, struct sun6i_isp_device, proc.notifier); > > > + struct sun6i_isp_proc_async_subdev *proc_async_subdev = > > > + container_of(async_subdev, struct sun6i_isp_proc_async_subdev, > > > + async_subdev); > > > + struct sun6i_isp_proc *proc = &isp_dev->proc; > > > + struct sun6i_isp_proc_source *source = proc_async_subdev->source; > > > + bool enabled; > > > + > > > + switch (source->endpoint.base.port) { > > > + case SUN6I_ISP_PORT_CSI0: > > > + source = &proc->source_csi0; > > > + enabled = true; > > > + break; > > > + case SUN6I_ISP_PORT_CSI1: > > > + source = &proc->source_csi1; > > > + enabled = !proc->source_csi0.expected; > > > + break; > > > + default: > > > + break; > > > + } > > > + > > > + source->subdev = remote_subdev; > > > + > > > + return sun6i_isp_proc_link(isp_dev, SUN6I_ISP_PROC_PAD_SINK_CSI, > > > + remote_subdev, enabled); > > > +} > > > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_proc.c:418:2: error: variable 'enabled' is used uninitialized whenever switch default is taken [-Werror,-Wsometimes-uninitialized] > > default: > > ^~~~~~~ > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_proc.c:425:23: note: uninitialized use occurs here > > remote_subdev, enabled); > > ^~~~~~~ > > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_proc.c:407:14: note: initialize the variable 'enabled' to silence this warning > > bool enabled; > > ^ > > = 0 > > > > Should there be an early return in the default case? > > > > I do not mind sending patches if you are unable to, assuming I have the > > right fixes. > > > > Cheers, > > Nathan > > -- Paul Kocialkowski, Bootlin Embedded Linux and kernel engineering https://bootlin.com