[src/riastradh-drm2]: src/sys/external/bsd/drm2/include/drm Implement a bus_d...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/6cc37e201754
branches:  riastradh-drm2
changeset: 788517:6cc37e201754
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Sep 08 15:39:48 2013 +0000

description:
Implement a bus_dmamem_wire_uvm_object hack.

This is fit only for x86 at the moment -- it parrots the x86
bus_dmamem_alloc code but with uvm_obj_wirepages instead of
uvm_pglistalloc.

XXX THIS IS A MEGA-KLUDGE THAT NEEDS TO BE DONE PROPERLY.

diffstat:

 sys/external/bsd/drm2/include/drm/bus_dma_hacks.h |  110 ++++++++++++++++++++++
 1 files changed, 110 insertions(+), 0 deletions(-)

diffs (114 lines):

diff -r c31cfe9ced11 -r 6cc37e201754 sys/external/bsd/drm2/include/drm/bus_dma_hacks.h
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/external/bsd/drm2/include/drm/bus_dma_hacks.h Sun Sep 08 15:39:48 2013 +0000
@@ -0,0 +1,110 @@
+/*     $NetBSD: bus_dma_hacks.h,v 1.1.2.1 2013/09/08 15:39:48 riastradh Exp $  */
+
+/*-
+ * Copyright (c) 2013 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Taylor R. Campbell.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef        _DRM_BUS_DMA_HACKS_H_
+#define        _DRM_BUS_DMA_HACKS_H_
+
+#include <sys/cdefs.h>
+#include <sys/bus.h>
+
+#include <uvm/uvm.h>
+#include <uvm/uvm_extern.h>
+
+/* XXX This is x86-specific bollocks.  */
+
+static inline int
+bus_dmamem_wire_uvm_object(bus_dma_tag_t tag, struct uvm_object *uobj,
+    off_t start, bus_size_t size, struct pglist *pages, bus_size_t alignment,
+    bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs,
+    int flags)
+{
+       struct pglist pageq;
+       struct vm_page *page;
+       bus_addr_t prev_addr, addr;
+       unsigned int i;
+       int error;
+
+       KASSERT(size <= __type_max(off_t));
+       KASSERT(start <= (__type_max(off_t) - size));
+       KASSERT(alignment == PAGE_SIZE); /* XXX */
+       KASSERT(0 < nsegs);
+
+       if (pages == NULL) {
+               TAILQ_INIT(&pageq);
+               pages = &pageq;
+       }
+
+       error = uvm_obj_wirepages(uobj, start, (start + size), pages);
+       if (error)
+               goto fail0;
+
+       page = TAILQ_FIRST(pages);
+       KASSERT(page != NULL);
+
+       addr = VM_PAGE_TO_PHYS(page);
+       segs[0].ds_addr = addr;
+       segs[0].ds_len = PAGE_SIZE;
+
+       i = 0;
+       while ((page = TAILQ_NEXT(page, pageq.queue)) != NULL) {
+               prev_addr = addr;
+               addr = VM_PAGE_TO_PHYS(page);
+               if ((addr == (prev_addr + PAGE_SIZE)) &&
+                   ((addr & boundary) == (prev_addr & boundary))) {
+                       segs[i].ds_len += PAGE_SIZE;
+               } else {
+                       i += 1;
+                       if (i >= nsegs) {
+                               error = EFBIG;
+                               goto fail1;
+                       }
+                       segs[i].ds_addr = addr;
+                       segs[i].ds_len = PAGE_SIZE;
+               }
+       }
+
+       /* Success!  */
+       *rsegs = (i + 1);
+       return 0;
+
+fail1: uvm_obj_unwirepages(uobj, start, (start + size));
+fail0: return error;
+}
+
+static inline void
+bus_dmamem_unwire_uvm_object(bus_dma_tag_t tag __unused,
+    struct uvm_object *uobj, off_t start, bus_size_t size,
+    bus_dma_segment_t *segs __unused, int nsegs __unused)
+{
+       uvm_obj_unwirepages(uobj, start, (start + size));
+}
+
+#endif /* _DRM_BUS_DMA_HACKS_H_ */