[src/trunk]: src/sys/arch/powerpc/powerpc powerpc: Implement bus_dmamap_load_...

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

details:   https://anonhg.NetBSD.org/src/rev/8f0f79789364
branches:  trunk
changeset: 361596:8f0f79789364
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Wed Feb 16 23:30:52 2022 +0000

description:
powerpc: Implement bus_dmamap_load_raw.

Can probably delete some of the round-trips between bus addresses and
physical addresses -- did these only to copy the logic already in
_bus_dmamap_load_buffer.

diffstat:

 sys/arch/powerpc/powerpc/bus_dma.c |  94 ++++++++++++++++++++++++++++++++++++-
 1 files changed, 90 insertions(+), 4 deletions(-)

diffs (119 lines):

diff -r f581d0b407c9 -r 8f0f79789364 sys/arch/powerpc/powerpc/bus_dma.c
--- a/sys/arch/powerpc/powerpc/bus_dma.c        Wed Feb 16 23:30:10 2022 +0000
+++ b/sys/arch/powerpc/powerpc/bus_dma.c        Wed Feb 16 23:30:52 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: bus_dma.c,v 1.52 2020/07/06 10:31:24 rin Exp $ */
+/*     $NetBSD: bus_dma.c,v 1.53 2022/02/16 23:30:52 riastradh Exp $   */
 
 /*-
  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
@@ -33,7 +33,7 @@
 #define _POWERPC_BUS_DMA_PRIVATE
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.52 2020/07/06 10:31:24 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.53 2022/02/16 23:30:52 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ppcarch.h"
@@ -401,12 +401,98 @@
 /*
  * Like _bus_dmamap_load(), but for raw memory allocated with
  * bus_dmamem_alloc().
+ *
+ * XXX This is too much copypasta of _bus_dmamap_load_buffer.
  */
 int
-_bus_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map, bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags)
+_bus_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map,
+    bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags)
 {
+       bus_size_t sgsize, isgsize;
+       bus_size_t busaddr, curaddr, lastaddr, baddr, bmask;
+       int seg, iseg, first;
 
-       panic("_bus_dmamap_load_raw: not implemented");
+       if (size == 0)
+               return 0;
+
+       lastaddr = 0;
+       bmask = ~(map->_dm_boundary - 1);
+
+       first = 0;
+       iseg = 0;
+       busaddr = segs[iseg].ds_addr;
+       isgsize = segs[iseg].ds_len;
+       for (seg = 0; size > 0;) {
+               /*
+                * Get the physical address for this segment.
+                */
+               curaddr = BUS_MEM_TO_PHYS(t, busaddr);
+
+               /*
+                * If we're beyond the bounce threshold, notify
+                * the caller.
+                */
+               if (map->_dm_bounce_thresh != 0 &&
+                   curaddr >= map->_dm_bounce_thresh)
+                       return EINVAL;
+
+               /*
+                * Compute the segment size, and adjust counts.
+                */
+               sgsize = PAGE_SIZE - ((u_long)curaddr & PGOFSET);
+               sgsize = MIN(sgsize, isgsize);
+               sgsize = MIN(sgsize, size);
+               sgsize = MIN(sgsize, map->dm_maxsegsz);
+
+               /*
+                * Make sure we don't cross any boundaries.
+                */
+               if (map->_dm_boundary > 0) {
+                       baddr = (curaddr + map->_dm_boundary) & bmask;
+                       if (sgsize > (baddr - curaddr))
+                               sgsize = (baddr - curaddr);
+               }
+
+               /*
+                * Insert chunk into a segment, coalescing with
+                * the previous segment if possible.
+                */
+               if (first) {
+                       map->dm_segs[seg].ds_addr =
+                           PHYS_TO_BUS_MEM(t, curaddr);
+                       map->dm_segs[seg].ds_len = sgsize;
+                       first = 0;
+               } else {
+                       if (curaddr == lastaddr &&
+                           (map->dm_segs[seg].ds_len + sgsize) <=
+                            map->dm_maxsegsz &&
+                           (map->_dm_boundary == 0 ||
+                            (map->dm_segs[seg].ds_addr & bmask) ==
+                            (PHYS_TO_BUS_MEM(t, curaddr) & bmask)))
+                               map->dm_segs[seg].ds_len += sgsize;
+                       else {
+                               if (++seg >= map->_dm_segcnt)
+                                       break;
+                               map->dm_segs[seg].ds_addr =
+                                       PHYS_TO_BUS_MEM(t, curaddr);
+                               map->dm_segs[seg].ds_len = sgsize;
+                       }
+               }
+
+               lastaddr = curaddr + sgsize;
+               size -= sgsize;
+               if ((isgsize -= sgsize) == 0) {
+                       iseg++;
+                       KASSERT(iseg < nsegs);
+                       busaddr = segs[iseg].ds_addr;
+                       isgsize = segs[iseg].ds_len;
+               }
+       }
+
+       if (size > 0)
+               return EFBIG;
+
+       return 0;
 }
 
 /*