implement dmamap_load (stolen from i386) for powerpc.

This is required for USB support.
(with this a a bit more the root hub configures).

diff --git a/sys/arch/powerpc/powerpc/dma.c b/sys/arch/powerpc/powerpc/dma.c
index faba6dd..cb7d5c7 100644 (file)
--- a/sys/arch/powerpc/powerpc/dma.c
+++ b/sys/arch/powerpc/powerpc/dma.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: dma.c,v 1.1 2000/03/20 07:05:52 rahnds Exp $  */
+/*     $OpenBSD: dma.c,v 1.2 2000/03/31 04:12:58 rahnds Exp $  */
 
 /*
  * Copyright (c) 1998 Michael Shalayeff
@@ -92,16 +92,99 @@ _dmamap_destroy(v, map)
        free(map, M_DEVBUF);
 }
 
+/*
+ * Common function for loading a DMA map with a linear buffer.  May
+ * be called by bus-specific DMA map load functions.
+ */
 int
-_dmamap_load(v, map, addr, size, p, flags)
-       void *v;
+_dmamap_load(t, map, buf, buflen, p, flags)
+       void * t;
        bus_dmamap_t map;
-       void *addr;
-       bus_size_t size;
+       void *buf;
+       bus_size_t buflen;
        struct proc *p;
        int flags;
 {
-       panic("_dmamap_load: not implemented");
+       bus_size_t sgsize;
+       bus_addr_t curaddr, lastaddr, baddr, bmask;
+       caddr_t vaddr = buf;
+       int first, seg;
+       pmap_t pmap;
+
+       /*
+        * Make sure that on error condition we return "no valid mappings".
+        */
+       map->dm_nsegs = 0;
+       if (buflen > map->_dm_size)
+               return (EINVAL);
+
+       if (p != NULL)
+               pmap = p->p_vmspace->vm_map.pmap;
+       else
+               pmap = pmap_kernel();
+
+       lastaddr = ~0;          /* XXX gcc */
+       bmask  = ~(map->_dm_boundary - 1);
+
+       for (first = 1, seg = 0; buflen > 0; ) {
+               /*
+                * Get the physical address for this segment.
+                */
+               curaddr = (bus_addr_t)pmap_extract(pmap, (vm_offset_t)vaddr);
+
+               /*
+                * Compute the segment size, and adjust counts.
+                */
+               sgsize = NBPG - ((u_long)vaddr & PGOFSET);
+               if (buflen < sgsize)
+                       sgsize = buflen;
+
+               /*
+                * 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
+                * previous segment if possible.
+                */
+               if (first) {
+                       map->dm_segs[seg].ds_addr = 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) ==
+                            (curaddr & bmask)))
+                               map->dm_segs[seg].ds_len += sgsize;
+                       else {
+                               if (++seg >= map->_dm_segcnt)
+                                       break;
+                               map->dm_segs[seg].ds_addr = curaddr;
+                               map->dm_segs[seg].ds_len = sgsize;
+                       }
+               }
+
+               lastaddr = curaddr + sgsize;
+               vaddr += sgsize;
+               buflen -= sgsize;
+       }
+
+       /*
+        * Did we fit?
+        */
+       if (buflen != 0)
+               return (EFBIG);         /* XXX better return value here? */
+
+       map->dm_nsegs = seg + 1;
+       return (0);
 }
 
 int
@@ -173,16 +256,20 @@ _dmamem_alloc(v, size, alignment, boundary, segs, nsegs, rsegs, flags)
        va = uvm_pagealloc_contig(size, VM_MIN_KERNEL_ADDRESS,
                                        VM_MAX_KERNEL_ADDRESS, NBPG);
 #else
+# if 0
        vm_page_alloc_memory(size, VM_MIN_KERNEL_ADDRESS,
                VM_MAX_KERNEL_ADDRESS,
            alignment, boundary, (void *)&va, nsegs, (flags & BUS_DMA_NOWAIT));
+# else
+       va = kmem_alloc_wait(phys_map, NBPG); /* XXX */
+# endif
 #endif
        if (va == NULL)
                return (ENOMEM);
 
        segs[0].ds_addr = va;
        segs[0].ds_len = size;
-       *rsegs = 1;
+       *rsegs = nsegs;
 
 #if 0
        /* XXX for now */