For pages that have the TTM_PAGE_FLAG_DMA32 flag set we use the DMA API. We save the bus address in our array which we use to program the GART (see "radeon/ttm/PCIe: Use dma_addr if TTM has set it." and "nouveau/ttm/PCIe: Use dma_addr if TTM has set it."). The reason behind using the DMA API is that under Xen we would end up programming the GART with the bounce buffer (SWIOTLB) DMA address instead of the physical DMA address of the TTM page. The reason being that alloc_page with GFP_DMA32 does not allocate pages under the the 4GB mark when running under Xen hypervisor. Under baremetal this means we do the DMA API call earlier instead of when we program the GART. For details please refer to: https://lkml.org/lkml/2011/1/7/251 [v2: Fixed indentation, revised desc, added Reviewed-by] Reviewed-by: Thomas Hellstrom <thomas@shipmail.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Ian Campbell <ian.campbell@citrix.com> |
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.. | ||
i2c | ||
i810 | ||
i830 | ||
i915 | ||
mga | ||
nouveau | ||
r128 | ||
radeon | ||
savage | ||
sis | ||
tdfx | ||
ttm | ||
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_modes.h | ||
drm_edid.c | ||
drm_encoder_slave.c | ||
drm_fb_helper.c | ||
drm_fops.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_proc.c | ||
drm_scatter.c | ||
drm_sman.c | ||
drm_stub.c | ||
drm_sysfs.c | ||
drm_trace_points.c | ||
drm_trace.h | ||
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