<div class="gmail_quote">On Tue, Dec 14, 2010 at 12:11 AM, Jerome Glisse <<a href="mailto:j.glisse@gmail.com">j.glisse@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <div><div></div><div class="h5">On Mon, Dec 13, 2010 at 10:18 AM, Arnd Bergmann <<a href="mailto:arnd@arndb.de">arnd@arndb.de</a>> wrote: > On Monday 13 December 2010, Jammy Zhou wrote: >> On Mon, Dec 13, 2010 at 4:45 AM, Linus Walleij <<a href="mailto:linus.walleij@linaro.org">linus.walleij@linaro.org</a>>wrote: >> >> > On 11 December 2010 22:41, Arnd Bergmann <<a href="mailto:arnd@arndb.de">arnd@arndb.de</a>> wrote: >> > >> > * amd-gpu -- a single but huge driver for the GPU. As is normally the >> >> case with GPU drivers, we can expect long discussions >> >> before it will get considered for mainline >> >> 4 patches >> >> 98 files changed, 278321 insertions(+), 0 deletions(-) >> >> >> > >> > Just out of curiosity, following the discussion between Dave Airlie >> > and Codeaurora this summer re GPU driver shims. >> > >> > Is the AMD GPU exposing all functionality in its kernel driver or >> > is there some userspace blob somewhere with lots of e.g. GL >> > goodies? >> > >> All the functionality for the kernel driver of AMD GPU Z430/Z160 (now >> belongs to Qualcom) is exposed. But we need accompanied userspace library to >> call these functionality (buffer management, command submission, ...). > > Who owns these components? If it's closed source, the only options we > have are lobbying for complete release of the specs for a reimplementation > or reverse-engineering the drivers, which may at least get easier with > a user space driver than it would be with a kernel driver. > > Until there is a solution with an open source user space part, I would > suggest that the driver better be dropped from the Freescale BSP and > we should at least not waste time reviewing it. > > Arnd </div></div>From a quick look it also seems that the API exposed to userspace would allow easy abuse of the GPU to access any system ram. There is a reason we do expensive command checking in the other amd gpu driver (drivers/gpu/drm/radeon/*cs.c files) </blockquote><div> No, the memory used by the GPU is reserved at boot time, so I think there is no such a problem. </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> Cheers, Jerome </blockquote></div>