Posted today to the Linux kernel mailing list was the patch series for introducing the AMD ISP4 driver to the mainline kernel. This supports the image signal processor IP that to date is found with HP’s Strix Halo powered ZBook Ultra G1a laptop. With time, future AMD Ryzen laptops will also likely be leveraging this ISP technology for offloading more webcamera work from the CPU, but for now the HP ZBook Ultra G1a is the main beneficiary of this open-source driver.
The necessary patches for the AMD ISP4 to the other drivers such as the AMDGPU kernel graphics driver and x86 platform driver and AMD pin control driver have already been upstreamed. With Linux 6.17 the last bit remaining for enabling the web camera support on the HP ZBook Ultra G1a is the AMD ISP4 driver itself. Sent out today was the third iteration of this driver.
This driver update includes some fixes and also adapts to new AMD ISP firmware files.
The change-log as part of the v3 patch series elaborates:
– All the dependent patches in other modules (drm/amd/amdgpu, platform/x86, pinctrl/amd) merged on upstream mainline kernel v6.17.
– Removed usage of amdgpu structs in ISP driver. Added helper functions in amdgpu accepting opaque params from ISP driver to allocate and release ISP GART buffers.
– Moved sensor and MIPI phy control entirely into ISP FW instead of the previous hybrid approach controlling sensor from both FW and x86 (sensor driver).
– Removed phy configuration and sensor binding as x86 (sensor driver) had relinquished the sensor control for ISP FW. With this approach the driver will be exposed as web camera like interface.
– New FW with built-in sensor driver is submitted on upstream linux-firmware repo.
– Please note the new FW submitted is not directly compatible with OEM Kernel ISP4.0 and the previous ISP V2 patch series.
– If intend to use the new FW, please rebuild OEM ISP4.0 Kernel with CONFIG_VIDEO_OV05C10=N and CONFIG_PINCTRL_AMDISP=Y.
– Included critical fixes from Sultan Alsawaf branch related to managing lifetime of isp buffers.
media: amd: isp4: Add missing refcount tracking to mmap memop
media: amd: isp4: Don’t put or unmap the dmabuf when detaching
media: amd: isp4: Don’t increment refcount when dmabuf export fails
media: amd: isp4: Fix possible use-after-free in isp4vid_vb2_put()
media: amd: isp4: Always export a new dmabuf from get_dmabuf memop
media: amd: isp4: Fix implicit dmabuf lifetime tracking
media: amd: isp4: Fix possible use-after-free when putting implicit dmabuf
media: amd: isp4: Simplify isp4vid_get_dmabuf() arguments
media: amd: isp4: Move up buf->vaddr check in isp4vid_get_dmabuf()
media: amd: isp4: Remove unused userptr memops
media: amd: isp4: Add missing cleanup on error in isp4vid_vb2_alloc()
media: amd: isp4: Release queued buffers on error in start_streaming
– Addressed all code related upstream comments
– Fix typo errors and other cosmetic issue.
Here is to hoping this AMD ISP4 driver will be ready for the mainline kernel with the upcoming Linux 6.18 kernel cycle for enabling the web camera support initially on the HP ZBook Ultra G1a without having to resort to any out-of-tree patches / vendor kernels.
