mirror of https://gitee.com/openkylin/linux.git
32 lines
1.6 KiB
Plaintext
32 lines
1.6 KiB
Plaintext
config DRM_RADEON_KMS
|
|
bool "Enable modesetting on radeon by default - NEW DRIVER"
|
|
depends on DRM_RADEON
|
|
select BACKLIGHT_CLASS_DEVICE
|
|
help
|
|
Choose this option if you want kernel modesetting enabled by default.
|
|
|
|
This is a completely new driver. It's only part of the existing drm
|
|
for compatibility reasons. It requires an entirely different graphics
|
|
stack above it and works very differently from the old drm stack.
|
|
i.e. don't enable this unless you know what you are doing it may
|
|
cause issues or bugs compared to the previous userspace driver stack.
|
|
|
|
When kernel modesetting is enabled the IOCTL of radeon/drm
|
|
driver are considered as invalid and an error message is printed
|
|
in the log and they return failure.
|
|
|
|
KMS enabled userspace will use new API to talk with the radeon/drm
|
|
driver. The new API provide functions to create/destroy/share/mmap
|
|
buffer object which are then managed by the kernel memory manager
|
|
(here TTM). In order to submit command to the GPU the userspace
|
|
provide a buffer holding the command stream, along this buffer
|
|
userspace have to provide a list of buffer object used by the
|
|
command stream. The kernel radeon driver will then place buffer
|
|
in GPU accessible memory and will update command stream to reflect
|
|
the position of the different buffers.
|
|
|
|
The kernel will also perform security check on command stream
|
|
provided by the user, we want to catch and forbid any illegal use
|
|
of the GPU such as DMA into random system memory or into memory
|
|
not owned by the process supplying the command stream.
|