Parse and use "dma-ranges" property to do the appropriate dma address

translations on machines like the Raspberry Pi.

ok jsg@

2 files changed, 85 insertions, 5 deletions

diff --git a/sys/arch/arm64/dev/simplebus.c b/sys/arch/arm64/dev/simplebus.c
index 27c4376ce61..8d0660176d1 100644
--- a/sys/arch/arm64/dev/simplebus.c
+++ b/sys/arch/arm64/dev/simplebus.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: simplebus.c,v 1.3 2017/01/23 06:13:34 kettenis Exp $ */
+/* $OpenBSD: simplebus.c,v 1.4 2017/01/23 10:46:02 kettenis Exp $ */
 /*
  * Copyright (c) 2016 Patrick Wildt <patrick@blueri.se>
  *
@@ -31,7 +31,10 @@ int simplebus_match(struct device *, void *, void *);
 void simplebus_attach(struct device *, struct device *, void *);
 
 void simplebus_attach_node(struct device *, int);
-int simplebus_bs_map(bus_space_tag_t, bus_addr_t, bus_size_t, int, bus_space_handle_t *);
+int simplebus_bs_map(bus_space_tag_t, bus_addr_t, bus_size_t, int,
+    bus_space_handle_t *);
+int simplebus_dmamap_load_buffer(bus_dma_tag_t, bus_dmamap_t, void *,
+    bus_size_t, struct proc *, int, paddr_t *, int *, int);
 
 struct cfattach simplebus_ca = {
 	sizeof(struct simplebus_softc), simplebus_match, simplebus_attach
@@ -88,12 +91,26 @@ simplebus_attach(struct device *parent, struct device *self, void *aux)
 	sc->sc_bus._space_map = simplebus_bs_map;
 
 	sc->sc_rangeslen = OF_getproplen(sc->sc_node, "ranges");
-	if (sc->sc_rangeslen > 0 && !(sc->sc_rangeslen % sizeof(uint32_t))) {
+	if (sc->sc_rangeslen > 0 &&
+	    (sc->sc_rangeslen % sizeof(uint32_t)) == 0) {
 		sc->sc_ranges = malloc(sc->sc_rangeslen, M_TEMP, M_WAITOK);
 		OF_getpropintarray(sc->sc_node, "ranges", sc->sc_ranges,
 		    sc->sc_rangeslen);
 	}
 
+	memcpy(&sc->sc_dma, sc->sc_dmat, sizeof(sc->sc_dma));
+	sc->sc_dma._dmamap_load_buffer = simplebus_dmamap_load_buffer;
+	sc->sc_dma._cookie = sc;
+
+	sc->sc_dmarangeslen = OF_getproplen(sc->sc_node, "dma-ranges");
+	if (sc->sc_dmarangeslen > 0 &&
+	    (sc->sc_dmarangeslen % sizeof(uint32_t)) == 0) {
+		sc->sc_dmaranges = malloc(sc->sc_dmarangeslen,
+		    M_TEMP, M_WAITOK);
+		OF_getpropintarray(sc->sc_node, "dma-ranges",
+		    sc->sc_dmaranges, sc->sc_dmarangeslen);
+	}
+
 	/* Scan the whole tree. */
 	sc->sc_early = 1;
 	for (node = OF_child(sc->sc_node); node; node = OF_peer(node))
@@ -138,7 +155,7 @@ simplebus_attach_node(struct device *self, int node)
 	fa.fa_name = "";
 	fa.fa_node = node;
 	fa.fa_iot = &sc->sc_bus;
-	fa.fa_dmat = sc->sc_dmat;
+	fa.fa_dmat = &sc->sc_dma;
 	fa.fa_acells = sc->sc_acells;
 	fa.fa_scells = sc->sc_scells;
 
@@ -239,3 +256,63 @@ simplebus_bs_map(bus_space_tag_t t, bus_addr_t bpa, bus_size_t size,
 
 	return ESRCH;
 }
+
+int
+simplebus_dmamap_load_buffer(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
+    bus_size_t buflen, struct proc *p, int flags, paddr_t *lastaddrp,
+    int *segp, int first)
+{
+	struct simplebus_softc *sc = t->_cookie;
+	int rlen, rone, seg;
+	int firstseg = *segp;
+	int error;
+
+	error = sc->sc_dmat->_dmamap_load_buffer(t, map, buf, buflen, p,
+	    flags, lastaddrp, segp, first);
+	if (error)
+		return error;
+
+	if (sc->sc_dmaranges == NULL)
+		return 0;
+
+	rlen = sc->sc_dmarangeslen / sizeof(uint32_t);
+	rone = sc->sc_pacells + sc->sc_acells + sc->sc_scells;
+
+	/* For each segment. */
+	for (seg = firstseg; seg <= *segp; seg++) {
+		uint64_t addr, size, rfrom, rto, rsize;
+		uint32_t *range;
+
+		addr = map->dm_segs[seg].ds_addr;
+		size = map->dm_segs[seg].ds_len;
+
+		/* For each range. */
+		for (range = sc->sc_dmaranges; rlen >= rone;
+		     rlen -= rone, range += rone) {
+			/* Extract from and size, so we can see if we fit. */
+			rfrom = range[sc->sc_acells];
+			if (sc->sc_pacells == 2)
+				rfrom = (rfrom << 32) + range[sc->sc_acells + 1];
+
+			rsize = range[sc->sc_acells + sc->sc_pacells];
+			if (sc->sc_scells == 2)
+				rsize = (rsize << 32) +
+				    range[sc->sc_acells + sc->sc_pacells + 1];
+
+			/* Try next, if we're not in the range. */
+			if (addr < rfrom || (addr + size) > (rfrom + rsize))
+				continue;
+
+			/* All good, extract to address and translate. */
+			rto = range[0];
+			if (sc->sc_pacells == 2)
+				rto = (rto << 32) + range[1];
+
+			map->dm_segs[seg].ds_addr -= rfrom;
+			map->dm_segs[seg].ds_addr += rto;
+			break;
+		}
+	}
+
+	return 0;
+}
diff --git a/sys/arch/arm64/dev/simplebusvar.h b/sys/arch/arm64/dev/simplebusvar.h
index 4bde6e92bd5..084c17bbfbe 100644
--- a/sys/arch/arm64/dev/simplebusvar.h
+++ b/sys/arch/arm64/dev/simplebusvar.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: simplebusvar.h,v 1.1 2016/12/17 23:38:33 patrick Exp $ */
+/* $OpenBSD: simplebusvar.h,v 1.2 2017/01/23 10:46:02 kettenis Exp $ */
 /*
  * Copyright (c) 2016 Patrick Wildt <patrick@blueri.se>
  *
@@ -25,8 +25,11 @@ struct simplebus_softc {
 	int			 sc_pacells;
 	int			 sc_pscells;
 	struct bus_space	 sc_bus;
+	struct machine_bus_dma_tag sc_dma;
 	int			*sc_ranges;
 	int			 sc_rangeslen;
+	int			*sc_dmaranges;
+	int			 sc_dmarangeslen;
 	int			 sc_early;
 };