Changeset aaceebc4 in mainline for kernel/generic/include/mm/frame.h

Timestamp:

2013-03-12T23:10:57Z (11 years ago)

Author:

Jan Vesely <jano.vesely@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

cf39b2e

Parents:

428bd07

Message:

Create DMA zone.

use dma zone for dma_map_anonymous calls.
create non-available zone if all pages in that zone are used.
make occupying pages in non-available zones a no-op

This enables ISA DMA on configurations with more than 16 MB of ram

File:

• kernel/generic/include/mm/frame.h (modified) (3 diffs)

kernel/generic/include/mm/frame.h

@@ -63 +63 @@
 /** Allocate a frame which cannot be identity-mapped. */
 #define FRAME_HIGHMEM     0x20
+/** Allocate a frame which needs to be from DMA zone. */
+#define FRAME_DMA         0x40
 
 typedef uint8_t zone_flags_t;
@@ -77 +79 @@
 /** Zone contains memory that cannot be identity-mapped */
 #define ZONE_HIGHMEM    0x10
+/** Zone contains memory suitable for old ISA DMA */
+#define ZONE_DMA        0x20
 
 /** Mask of zone bits that must be matched exactly. */
@@ -82 +86 @@
 
 #define FRAME_TO_ZONE_FLAGS(ff) \
-        ((((ff) & FRAME_LOWMEM) ? ZONE_LOWMEM : \
+        ((((ff) & FRAME_DMA) ? ZONE_DMA : \
+            (((ff) & FRAME_LOWMEM) ? ZONE_LOWMEM : \
             (((ff) & FRAME_HIGHMEM) ? ZONE_HIGHMEM : \
-            ZONE_LOWMEM /* | ZONE_HIGHMEM */)) | \
-            ZONE_AVAILABLE) 
+            ZONE_LOWMEM /* | ZONE_HIGHMEM */))) | \
+            ZONE_AVAILABLE)
 
 #define ZONE_FLAGS_MATCH(zf, f) \