Module Name: src
Committed By: matt
Date: Fri Oct 19 11:57:58 UTC 2012
Modified Files:
src/sys/arch/arm/arm32: bus_dma.c
Log Message:
Make bus_dmamem_map aware of coherent dma regions. Also, take advantage
of the use/existance of PMAP_MAP_POOLPAGE to avoid redundant mappings.
To generate a diff of this commit:
cvs rdiff -u -r1.61 -r1.62 src/sys/arch/arm/arm32/bus_dma.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/arm/arm32/bus_dma.c
diff -u src/sys/arch/arm/arm32/bus_dma.c:1.61 src/sys/arch/arm/arm32/bus_dma.c:1.62
--- src/sys/arch/arm/arm32/bus_dma.c:1.61 Wed Oct 17 20:17:18 2012
+++ src/sys/arch/arm/arm32/bus_dma.c Fri Oct 19 11:57:58 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: bus_dma.c,v 1.61 2012/10/17 20:17:18 matt Exp $ */
+/* $NetBSD: bus_dma.c,v 1.62 2012/10/19 11:57:58 matt Exp $ */
/*-
* Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
@@ -33,7 +33,7 @@
#define _ARM32_BUS_DMA_PRIVATE
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.61 2012/10/17 20:17:18 matt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.62 2012/10/19 11:57:58 matt Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -706,6 +706,10 @@ static void
_bus_dmamap_sync_segment(vaddr_t va, paddr_t pa, vsize_t len, int ops, bool readonly_p)
{
KASSERT((va & PAGE_MASK) == (pa & PAGE_MASK));
+#if 0
+ printf("sync_segment: va=%#lx pa=%#lx len=%#lx ops=%#x ro=%d\n",
+ va, pa, len, ops, readonly_p);
+#endif
switch (ops) {
case BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE:
@@ -1178,6 +1182,39 @@ _bus_dmamem_map(bus_dma_tag_t t, bus_dma
segs, nsegs, (unsigned long)size, flags);
#endif /* DEBUG_DMA */
+#ifdef PMAP_MAP_POOLPAGE
+ /*
+ * If all of memory is mapped, and we are mapping a single physically
+ * contiguous area then this area is already mapped. Let's see if we
+ * avoid having a separate mapping for it.
+ */
+ if (nsegs == 1) {
+ paddr_t paddr = segs[0].ds_addr;
+ /*
+ * If this is a non-COHERENT mapping, then the existing kernel
+ * mapping is already compatible with it.
+ */
+ if ((flags & _BUS_DMAMAP_COHERENT) == 0) {
+ *kvap = (void *)PMAP_MAP_POOLPAGE(paddr);
+ return 0;
+ }
+ /*
+ * This is a COHERENT mapping, which unless this address is in
+ * a COHERENT dma range, will not be compatible.
+ */
+ if (t->_ranges != NULL) {
+ const struct arm32_dma_range * const dr =
+ _bus_dma_paddr_inrange(t->_ranges, t->_nranges,
+ paddr);
+ if (dr != NULL
+ && (dr->dr_flags & _BUS_DMAMAP_COHERENT) != 0) {
+ *kvap = (void *)PMAP_MAP_POOLPAGE(paddr);
+ return 0;
+ }
+ }
+ }
+#endif
+
size = round_page(size);
va = uvm_km_alloc(kernel_map, size, 0, UVM_KMF_VAONLY | kmflags);
@@ -1207,7 +1244,22 @@ _bus_dmamem_map(bus_dma_tag_t t, bus_dma
* contain the virtal addresses we are making
* uncacheable.
*/
- if (flags & BUS_DMA_COHERENT) {
+
+ bool uncached = (flags & BUS_DMA_COHERENT);
+ if (uncached) {
+ const struct arm32_dma_range * const dr =
+ _bus_dma_paddr_inrange(t->_ranges,
+ t->_nranges, pa);
+ /*
+ * If this dma region is coherent then there is
+ * no need for an uncached mapping.
+ */
+ if (dr != NULL
+ && (dr->dr_flags & _BUS_DMAMAP_COHERENT)) {
+ uncached = false;
+ }
+ }
+ if (uncached) {
cpu_dcache_wbinv_range(va, PAGE_SIZE);
cpu_sdcache_wbinv_range(va, pa, PAGE_SIZE);
cpu_drain_writebuf();
