Em Thu, 21 Jun 2018 18:58:37 +0000 <mario.limoncie...@dell.com> escreveu:
> > -----Original Message----- > > From: Mauro Carvalho Chehab [mailto:mchehab+sams...@kernel.org] > > Sent: Thursday, June 21, 2018 1:50 PM > > To: Limonciello, Mario > > Cc: pa...@ucw.cz; nico...@ndufresne.ca; linux-media@vger.kernel.org; > > sakari.ai...@linux.intel.com; niklas.soderl...@ragnatech.se; > > jerry.w...@intel.com > > Subject: Re: Software-only image processing for Intel "complex" cameras > > > > Em Thu, 21 Jun 2018 13:41:37 +0000 > > <mario.limoncie...@dell.com> escreveu: > > > > > > -----Original Message----- > > > > From: Pavel Machek [mailto:pa...@ucw.cz] > > > > Sent: Wednesday, June 20, 2018 4:12 PM > > > > To: Nicolas Dufresne > > > > Cc: linux-media@vger.kernel.org; sakari.ai...@linux.intel.com; > > > > niklas.soderl...@ragnatech.se; jerry.w...@intel.com; Limonciello, Mario > > > > Subject: Re: Software-only image processing for Intel "complex" cameras > > > > > > > > Hi! > > > > > > > > > > On Nokia N900, I have similar problems as Intel IPU3 hardware. > > > > > > > > > > > > Meeting notes say that pure software implementation is not fast > > > > > > enough, but that it may be useful for debugging. It would be also > > > > > > useful for me on N900, and probably useful for processing "raw" > > > > > > images > > > > > > from digital cameras. > > > > > > > > > > > > There is sensor part, and memory-to-memory part, right? What is > > > > > > the format of data from the sensor part? What operations would be > > > > > > expensive on the CPU? If we did everthing on the CPU, what would be > > > > > > maximum resolution where we could still manage it in real time? > > > > > > > > > > The IPU3 sensor produce a vendor specific form of bayer. If we manage > > > > > to implement support for this format, it would likely be done in > > > > > software. I don't think anyone can answer your other questions has no > > > > > one have ever implemented this, hence measure performance. > > > > > > > > I believe Intel has some estimates. > > > > > > > > What is the maximum resolution of camera in the current Dell systems? > > > > > > > > > > 5M camera sensor HW spec: > > > 2592x1944 > > > > > > 8M camera sensor HW spec: > > > 3264x2448 > > > > Looking at the ipu3 driver, I'm wandering how the library would identify > > the system components. The way VIDIOC_QUERYCAP is currently implemented > > doesn't help at all: > > > > static int cio2_v4l2_querycap(struct file *file, void *fh, > > struct v4l2_capability *cap) > > { > > struct cio2_device *cio2 = video_drvdata(file); > > > > strlcpy(cap->driver, CIO2_NAME, sizeof(cap->driver)); > > strlcpy(cap->card, CIO2_DEVICE_NAME, sizeof(cap->card)); > > snprintf(cap->bus_info, sizeof(cap->bus_info), > > "PCI:%s", pci_name(cio2->pci_dev)); > > > > return 0; > > } > > > > In order to allow the library to know more about the hardware, it > > would likely need to expose some model number to userspace. Ok, userspace > > could always call dmidecode, but that requires root privileges. We > > really don't want media apps to require root. > > > > So, perhaps caps->cap (or a MC caps equivalent call) should, instead be > > filled > > with values obtained from the BIOS DMI tables with some logic based on > > enum dmi_field: > > > > enum dmi_field { > > DMI_NONE, > > DMI_BIOS_VENDOR, > > DMI_BIOS_VERSION, > > DMI_BIOS_DATE, > > DMI_SYS_VENDOR, > > DMI_PRODUCT_NAME, > > DMI_PRODUCT_VERSION, > > DMI_PRODUCT_SERIAL, > > DMI_PRODUCT_UUID, > > DMI_PRODUCT_FAMILY, > > DMI_BOARD_VENDOR, > > DMI_BOARD_NAME, > > DMI_BOARD_VERSION, > > DMI_BOARD_SERIAL, > > DMI_BOARD_ASSET_TAG, > > DMI_CHASSIS_VENDOR, > > DMI_CHASSIS_TYPE, > > DMI_CHASSIS_VERSION, > > DMI_CHASSIS_SERIAL, > > DMI_CHASSIS_ASSET_TAG, > > DMI_STRING_MAX, > > }; > > > > e. g. something like: > > > > board_vendor = dmi_get_system_info(DMI_BOARD_VENDOR); > > board_name = dmi_get_system_info(DMI_BOARD_NAME); > > board_version = dmi_get_system_info(DMI_BOARD_NAME); > > product_name = dmi_get_system_info(DMI_PRODUCT_NAME); > > product_version = dmi_get_system_info(DMI_PRODUCT_VERSION); > > > > sprintf(dev->cap, "%s:%s:%s:%s", board_vendor, board_name, > > board_version, product_name, product_version); > > > > (the real code should check if the values are filled, as not all BIOS > > vendors use the > > same DMI fields) > > > > With that, the library can auto-adjust without needing to run anything as > > root. > > > Well actually most of those fields you're interested in are already exposed > to userspace > through sysfs /sys/class/dmi/id/ > > Can't the library just pull them from there? Good point. Yeah, the library could use them. > The one field that isn't exposed is actually the one I think you should key > off of though: > Product SKU number. So I would propose as part of this change that should > start to get > exposed to userspace too. > > The reasoning is I'm a little concerned in taking an approach that goes off > of marketing model number > specifically because it's creating an assumption that all systems with that > model number > have the exact same components. > > It's possible for two systems to have the same model number but to second > source for > example. This might not affect complex cameras, but I just want to make sure > it's taken > into consideration. At least going off of Product SKU will better narrow it > down. Yeah, the library should be able to uniquely match whatever components are inside a system, and just the marketing model number might not be enough. Right now, only dmidecode seems to get SKU number. On a quick look, it seems that a patch adding support for it was already proposed: https://lkml.org/lkml/2018/4/24/1166 And got accepted: https://lkml.org/lkml/2018/4/27/96 So, it seems we'll be covered for newer Kernel versions. Cheers, Mauro
