Module Name: src
Committed By: riastradh
Date: Wed May 28 16:13:02 UTC 2014
Modified Files:
src/sys/external/bsd/drm2/include/drm: intel-gtt.h
Log Message:
Explain the fields of struct intel_gtt for future reference.
To generate a diff of this commit:
cvs rdiff -u -r1.2 -r1.3 src/sys/external/bsd/drm2/include/drm/intel-gtt.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/external/bsd/drm2/include/drm/intel-gtt.h
diff -u src/sys/external/bsd/drm2/include/drm/intel-gtt.h:1.2 src/sys/external/bsd/drm2/include/drm/intel-gtt.h:1.3
--- src/sys/external/bsd/drm2/include/drm/intel-gtt.h:1.2 Tue Mar 18 18:20:43 2014
+++ src/sys/external/bsd/drm2/include/drm/intel-gtt.h Wed May 28 16:13:02 2014
@@ -1,4 +1,4 @@
-/* $NetBSD: intel-gtt.h,v 1.2 2014/03/18 18:20:43 riastradh Exp $ */
+/* $NetBSD: intel-gtt.h,v 1.3 2014/05/28 16:13:02 riastradh Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -41,13 +41,47 @@
#include <drm/drm_agp_netbsd.h>
struct intel_gtt {
+ /*
+ * GMADR, graphics memory address, a.k.a. the `aperture'.
+ * Access to bus addresses in the region starting here are
+ * remapped to physical system memory addresses programmed into
+ * the GTT (or GPU-local memory, for i810 chipsets, depending
+ * on the GTT entries). This corresponds to a prefix of the
+ * GPU's virtual address space. The virtual address space may
+ * be larger: in that case, there will be more GTT entries than
+ * pages in the aperture.
+ */
paddr_t gma_bus_addr;
+
+ /*
+ * Number of bytes of system memory stolen by the graphics
+ * device for frame buffer memory (but not for the GTT). These
+ * pages in memory -- if you know where they are -- can't be
+ * used by the CPU, but they can be programmed into the GTT for
+ * access from the GPU.
+ */
unsigned int stolen_size;
+
+ /*
+ * Total number of GTT entries, including entries for the GPU's
+ * virtual address space beyond the aperture.
+ */
unsigned int gtt_total_entries;
+
+ /*
+ * Number of GTT entries for pages that we can actually map
+ * into the aperture.
+ */
unsigned int gtt_mappable_entries;
+
+ /* Scratch page for unbound GTT entries. */
bus_dma_segment_t gtt_scratch_seg;
bus_dmamap_t gtt_scratch_map;
+
+ /* Bus space handle for the GTT itself. */
bus_space_handle_t gtt_bsh;
+
+ /* IOMMU-related quirk for certain chipsets. */
bool do_idle_maps;
};
