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46ddf19477
Provide a standardized sysfs interface for setting min, and max frequencies. The code which reads the limits were lifted from the debugfs files. As a brief explanation, the limits are similar to the CPU p-states. We have 3 states: RP0 - ie. max frequency RP1 - ie. "preferred min" frequency RPn - seriously lowest frequency Initially Daniel asked me to clamp the writes to supported values, but in conforming to the way the cpufreq drivers seem to work, instead return -EINVAL (noticed by Jesse in discussion). The values can be used by userspace wishing to control the limits of the GPU (see the CC list for people who care). v4: Make exceeding the soft limits return -EINVAL as well (Daniel) v3: bug fix (Ben) - was passing the MHz value to gen6_set_rps instead of the step value. To fix, deal only with step values by doing the divide at the top. v2: add the dropped mutex_unlock in error cases (Chris) EINVAL on both too min, or too max (Daniel) v2 Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> CC: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Ben Widawsky <ben@bwidawsk.net> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> |
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ast | ||
cirrus | ||
exynos | ||
gma500 | ||
i2c | ||
i810 | ||
i915 | ||
mga | ||
mgag200 | ||
nouveau | ||
r128 | ||
radeon | ||
savage | ||
shmobile | ||
sis | ||
tdfx | ||
ttm | ||
udl | ||
via | ||
vmwgfx | ||
ati_pcigart.c | ||
drm_agpsupport.c | ||
drm_auth.c | ||
drm_buffer.c | ||
drm_bufs.c | ||
drm_cache.c | ||
drm_context.c | ||
drm_crtc_helper.c | ||
drm_crtc.c | ||
drm_debugfs.c | ||
drm_dma.c | ||
drm_dp_i2c_helper.c | ||
drm_drv.c | ||
drm_edid_load.c | ||
drm_edid_modes.h | ||
drm_edid.c | ||
drm_encoder_slave.c | ||
drm_fb_cma_helper.c | ||
drm_fb_helper.c | ||
drm_fops.c | ||
drm_gem_cma_helper.c | ||
drm_gem.c | ||
drm_global.c | ||
drm_hashtab.c | ||
drm_info.c | ||
drm_ioc32.c | ||
drm_ioctl.c | ||
drm_irq.c | ||
drm_lock.c | ||
drm_memory.c | ||
drm_mm.c | ||
drm_modes.c | ||
drm_pci.c | ||
drm_platform.c | ||
drm_prime.c | ||
drm_proc.c | ||
drm_scatter.c | ||
drm_stub.c | ||
drm_sysfs.c | ||
drm_trace_points.c | ||
drm_trace.h | ||
drm_usb.c | ||
drm_vm.c | ||
Kconfig | ||
Makefile | ||
README.drm |
************************************************************ * For the very latest on DRI development, please see: * * http://dri.freedesktop.org/ * ************************************************************ The Direct Rendering Manager (drm) is a device-independent kernel-level device driver that provides support for the XFree86 Direct Rendering Infrastructure (DRI). The DRM supports the Direct Rendering Infrastructure (DRI) in four major ways: 1. The DRM provides synchronized access to the graphics hardware via the use of an optimized two-tiered lock. 2. The DRM enforces the DRI security policy for access to the graphics hardware by only allowing authenticated X11 clients access to restricted regions of memory. 3. The DRM provides a generic DMA engine, complete with multiple queues and the ability to detect the need for an OpenGL context switch. 4. The DRM is extensible via the use of small device-specific modules that rely extensively on the API exported by the DRM module. Documentation on the DRI is available from: http://dri.freedesktop.org/wiki/Documentation http://sourceforge.net/project/showfiles.php?group_id=387 http://dri.sourceforge.net/doc/ For specific information about kernel-level support, see: The Direct Rendering Manager, Kernel Support for the Direct Rendering Infrastructure http://dri.sourceforge.net/doc/drm_low_level.html Hardware Locking for the Direct Rendering Infrastructure http://dri.sourceforge.net/doc/hardware_locking_low_level.html A Security Analysis of the Direct Rendering Infrastructure http://dri.sourceforge.net/doc/security_low_level.html