/* $NetBSD: bus_dma.c,v 1.74 2022/07/26 20:08:54 andvar Exp $ */ /*- * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, * NASA Ames Research Center. * * 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. */ #include /* RCS ID & Copyright macro defns */ __KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.74 2022/07/26 20:08:54 andvar Exp $"); #include #include #include #include #include #include #include #include #define _ALPHA_BUS_DMA_PRIVATE #include #include #include static int _bus_dmamap_load_buffer_direct(bus_dma_tag_t, bus_dmamap_t, void *, bus_size_t, struct vmspace *, int, paddr_t *, int *, int); extern paddr_t avail_start, avail_end; /* from pmap.c */ #define DMA_COUNT_DECL(cnt) _DMA_COUNT_DECL(dma_direct, cnt) #define DMA_COUNT(cnt) _DMA_COUNT(dma_direct, cnt) static size_t _bus_dmamap_mapsize(int const nsegments) { KASSERT(nsegments > 0); return sizeof(struct alpha_bus_dmamap) + (sizeof(bus_dma_segment_t) * (nsegments - 1)); } /* * Common function for DMA map creation. May be called by bus-specific * DMA map creation functions. */ int _bus_dmamap_create(bus_dma_tag_t t, bus_size_t size, int nsegments, bus_size_t maxsegsz, bus_size_t boundary, int flags, bus_dmamap_t *dmamp) { struct alpha_bus_dmamap *map; void *mapstore; /* * Allocate and initialize the DMA map. The end of the map * is a variable-sized array of segments, so we allocate enough * room for them in one shot. * * Note we don't preserve the WAITOK or NOWAIT flags. Preservation * of ALLOCNOW notifies others that we've reserved these resources, * and they are not to be freed. * * The bus_dmamap_t includes one bus_dma_segment_t, hence * the (nsegments - 1). */ if ((mapstore = kmem_zalloc(_bus_dmamap_mapsize(nsegments), (flags & BUS_DMA_NOWAIT) ? KM_NOSLEEP : KM_SLEEP)) == NULL) return (ENOMEM); map = (struct alpha_bus_dmamap *)mapstore; map->_dm_size = size; map->_dm_segcnt = nsegments; map->_dm_maxmaxsegsz = maxsegsz; if (t->_boundary != 0 && t->_boundary < boundary) map->_dm_boundary = t->_boundary; else map->_dm_boundary = boundary; map->_dm_flags = flags & ~(BUS_DMA_WAITOK|BUS_DMA_NOWAIT); map->dm_maxsegsz = maxsegsz; map->dm_mapsize = 0; /* no valid mappings */ map->dm_nsegs = 0; map->_dm_window = NULL; *dmamp = map; return (0); } /* * Common function for DMA map destruction. May be called by bus-specific * DMA map destruction functions. */ void _bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map) { kmem_free(map, _bus_dmamap_mapsize(map->_dm_segcnt)); } /* * Utility function to load a linear buffer. lastaddrp holds state * between invocations (for multiple-buffer loads). segp contains * the starting segment on entrance, and the ending segment on exit. * first indicates if this is the first invocation of this function. */ static int _bus_dmamap_load_buffer_direct(bus_dma_tag_t t, bus_dmamap_t map, void *buf, size_t buflen, struct vmspace *vm, int flags, paddr_t *lastaddrp, int *segp, int first) { bus_size_t sgsize; bus_addr_t curaddr, lastaddr, baddr, bmask; vaddr_t vaddr = (vaddr_t)buf; int seg; bool address_is_valid __diagused; lastaddr = *lastaddrp; bmask = ~(map->_dm_boundary - 1); for (seg = *segp; buflen > 0 ; ) { /* * Get the physical address for this segment. */ address_is_valid = pmap_extract(vm->vm_map.pmap, vaddr, &curaddr); KASSERT(address_is_valid); /* * If we're beyond the current DMA window, indicate * that and try to fall back into SGMAPs. */ if (t->_wsize != 0 && curaddr >= t->_wsize) return (EINVAL); curaddr |= t->_wbase; /* * Compute the segment size, and adjust counts. */ sgsize = PAGE_SIZE - ((u_long)vaddr & PGOFSET); if (buflen < sgsize) sgsize = buflen; if (map->dm_maxsegsz < sgsize) 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 = curaddr; map->dm_segs[seg].ds_len = sgsize; first = 0; } else { if ((map->_dm_flags & DMAMAP_NO_COALESCE) == 0 && 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; } *segp = seg; *lastaddrp = lastaddr; /* * Did we fit? */ if (buflen != 0) { /* * If there is a chained window, we will automatically * fall back to it. */ return (EFBIG); /* XXX better return value here? */ } return (0); } DMA_COUNT_DECL(load); DMA_COUNT_DECL(load_next_window); /* * Common function for loading a direct-mapped DMA map with a linear * buffer. Called by bus-specific DMA map load functions with the * OR value appropriate for indicating "direct-mapped" for that * chipset. */ int _bus_dmamap_load_direct(bus_dma_tag_t t, bus_dmamap_t map, void *buf, bus_size_t buflen, struct proc *p, int flags) { paddr_t lastaddr; int seg, error; struct vmspace *vm; /* * Make sure that on error condition we return "no valid mappings". */ map->dm_mapsize = 0; map->dm_nsegs = 0; KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz); KASSERT((map->_dm_flags & (BUS_DMA_READ|BUS_DMA_WRITE)) == 0); if (buflen > map->_dm_size) return (EINVAL); if (p != NULL) { vm = p->p_vmspace; } else { vm = vmspace_kernel(); } seg = 0; error = _bus_dmamap_load_buffer_direct(t, map, buf, buflen, vm, flags, &lastaddr, &seg, 1); if (error == 0) { DMA_COUNT(load); map->dm_mapsize = buflen; map->dm_nsegs = seg + 1; map->_dm_window = t; } else if (t->_next_window != NULL) { /* * Give the next window a chance. */ DMA_COUNT(load_next_window); error = bus_dmamap_load(t->_next_window, map, buf, buflen, p, flags); } return (error); } DMA_COUNT_DECL(load_mbuf); DMA_COUNT_DECL(load_mbuf_next_window); /* * Like _bus_dmamap_load_direct(), but for mbufs. */ int _bus_dmamap_load_mbuf_direct(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m0, int flags) { paddr_t lastaddr; int seg, error, first; struct mbuf *m; /* * Make sure that on error condition we return "no valid mappings." */ map->dm_mapsize = 0; map->dm_nsegs = 0; KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz); KASSERT((map->_dm_flags & (BUS_DMA_READ|BUS_DMA_WRITE)) == 0); #ifdef DIAGNOSTIC if ((m0->m_flags & M_PKTHDR) == 0) panic("_bus_dmamap_load_mbuf_direct: no packet header"); #endif if (m0->m_pkthdr.len > map->_dm_size) return (EINVAL); first = 1; seg = 0; error = 0; for (m = m0; m != NULL && error == 0; m = m->m_next) { if (m->m_len == 0) continue; /* XXX Could be better about coalescing. */ /* XXX Doesn't check boundaries. */ switch (m->m_flags & (M_EXT|M_EXT_CLUSTER)) { case M_EXT|M_EXT_CLUSTER: /* XXX KDASSERT */ KASSERT(m->m_ext.ext_paddr != M_PADDR_INVALID); lastaddr = m->m_ext.ext_paddr + (m->m_data - m->m_ext.ext_buf); have_addr: if (first == 0 && ++seg >= map->_dm_segcnt) { error = EFBIG; break; } /* * If we're beyond the current DMA window, indicate * that and try to fall back into SGMAPs. */ if (t->_wsize != 0 && lastaddr >= t->_wsize) { error = EINVAL; break; } lastaddr |= t->_wbase; map->dm_segs[seg].ds_addr = lastaddr; map->dm_segs[seg].ds_len = m->m_len; lastaddr += m->m_len; break; case 0: lastaddr = m->m_paddr + M_BUFOFFSET(m) + (m->m_data - M_BUFADDR(m)); goto have_addr; default: error = _bus_dmamap_load_buffer_direct(t, map, m->m_data, m->m_len, vmspace_kernel(), flags, &lastaddr, &seg, first); } first = 0; } if (error == 0) { DMA_COUNT(load_mbuf); map->dm_mapsize = m0->m_pkthdr.len; map->dm_nsegs = seg + 1; map->_dm_window = t; } else if (t->_next_window != NULL) { /* * Give the next window a chance. */ DMA_COUNT(load_mbuf_next_window); error = bus_dmamap_load_mbuf(t->_next_window, map, m0, flags); } return (error); } DMA_COUNT_DECL(load_uio); DMA_COUNT_DECL(load_uio_next_window); /* * Like _bus_dmamap_load_direct(), but for uios. */ int _bus_dmamap_load_uio_direct(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio, int flags) { paddr_t lastaddr; int seg, i, error, first; bus_size_t minlen, resid; struct vmspace *vm; struct iovec *iov; void *addr; /* * Make sure that on error condition we return "no valid mappings." */ map->dm_mapsize = 0; map->dm_nsegs = 0; KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz); KASSERT((map->_dm_flags & (BUS_DMA_READ|BUS_DMA_WRITE)) == 0); resid = uio->uio_resid; iov = uio->uio_iov; vm = uio->uio_vmspace; first = 1; seg = 0; error = 0; for (i = 0; i < uio->uio_iovcnt && resid != 0 && error == 0; i++) { /* * Now at the first iovec to load. Load each iovec * until we have exhausted the residual count. */ minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len; addr = (void *)iov[i].iov_base; error = _bus_dmamap_load_buffer_direct(t, map, addr, minlen, vm, flags, &lastaddr, &seg, first); first = 0; resid -= minlen; } if (error == 0) { DMA_COUNT(load_uio); map->dm_mapsize = uio->uio_resid; map->dm_nsegs = seg + 1; map->_dm_window = t; } else if (t->_next_window != NULL) { /* * Give the next window a chance. */ DMA_COUNT(load_uio_next_window); error = bus_dmamap_load_uio(t->_next_window, map, uio, flags); } return (error); } /* * Like _bus_dmamap_load_direct(), but for raw memory. */ int _bus_dmamap_load_raw_direct(bus_dma_tag_t t, bus_dmamap_t map, bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags) { panic("_bus_dmamap_load_raw_direct: not implemented"); } /* * Common function for unloading a DMA map. May be called by * chipset-specific DMA map unload functions. */ void _bus_dmamap_unload_common(bus_dma_tag_t t, bus_dmamap_t map) { /* * No resources to free; just mark the mappings as * invalid. */ map->dm_maxsegsz = map->_dm_maxmaxsegsz; map->dm_mapsize = 0; map->dm_nsegs = 0; map->_dm_window = NULL; map->_dm_flags &= ~(BUS_DMA_READ|BUS_DMA_WRITE); } DMA_COUNT_DECL(unload); void _bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map) { KASSERT(map->_dm_window == t); DMA_COUNT(unload); _bus_dmamap_unload_common(t, map); } /* * Common function for DMA map synchronization. May be called * by chipset-specific DMA map synchronization functions. */ void _bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset, bus_size_t len, int ops) { alpha_mb(); } /* * Common function for DMA-safe memory allocation. May be called * by bus-specific DMA memory allocation functions. */ int _bus_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment, bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs, int flags) { return (_bus_dmamem_alloc_range(t, size, alignment, boundary, segs, nsegs, rsegs, flags, 0, trunc_page(avail_end))); } /* * Allocate physical memory from the given physical address range. * Called by DMA-safe memory allocation methods. */ int _bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment, bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs, int flags, paddr_t low, paddr_t high) { return (_bus_dmamem_alloc_range_common(t, size, alignment, boundary, segs, nsegs, rsegs, flags, low, high)); } /* * Common function for freeing DMA-safe memory. May be called by * bus-specific DMA memory free functions. */ void _bus_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs) { _bus_dmamem_free_common(t, segs, nsegs); } /* * Common function for mapping DMA-safe memory. May be called by * bus-specific DMA memory map functions. */ int _bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs, size_t size, void **kvap, int flags) { /* * If we're only mapping 1 segment, use K0SEG, to avoid * TLB thrashing. */ if (nsegs == 1) { *kvap = (void *)ALPHA_PHYS_TO_K0SEG(segs[0].ds_addr); return (0); } return (_bus_dmamem_map_common(t, segs, nsegs, size, kvap, flags, 0)); } /* * Common function for unmapping DMA-safe memory. May be called by * bus-specific DMA memory unmapping functions. */ void _bus_dmamem_unmap(bus_dma_tag_t t, void *kva, size_t size) { /* * Nothing to do if we mapped it with K0SEG. */ if (kva >= (void *)ALPHA_K0SEG_BASE && kva <= (void *)ALPHA_K0SEG_END) return; _bus_dmamem_unmap_common(t, kva, size); } /* * Common function for mmap(2)'ing DMA-safe memory. May be called by * bus-specific DMA mmap(2)'ing functions. */ paddr_t _bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs, off_t off, int prot, int flags) { bus_addr_t rv; rv = _bus_dmamem_mmap_common(t, segs, nsegs, off, prot, flags); if (rv == (bus_addr_t)-1) return (-1); return (alpha_btop((char *)rv)); }