c73e3771ea
This adds a qemu-specific hypervisor call to the pseries machine which allows to do what amounts to memmove, memcpy and xor over regions of physical memory such as the framebuffer. This is the simplest way to get usable framebuffer speed from SLOF since the framebuffer isn't mapped in the VRMA and so would otherwise require an hcall per 8 bytes access. The performance is still not great but usable, and can be improved with a more complex implementation of the hcall itself if needed. This also adds some documentation for the qemu-specific hypercalls that we add to PAPR along with a new qemu,hypertas-functions property that mirrors ibm,hypertas-functions and provides some discoverability for the new calls. Note: I chose note to advertise H_RTAS to the guest via that mechanism. This is done on purpose, the guest uses the normal RTAS interfaces provided by qemu (including SLOF) which internally calls H_RTAS. We might in the future implement part (or even all) of RTAS inside the guest like IBM's firmware does and replace H_RTAS with some finer grained set of private hypercalls. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Alexander Graf <agraf@suse.de> |
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| .. | ||
| acpi_pci_hotplug.txt | ||
| ivshmem_device_spec.txt | ||
| ppc-spapr-hcalls.txt | ||
| qcow2.txt | ||
| qed_spec.txt | ||