From 301afbce990a90ae28d264bd02cb39bb746887f6 Mon Sep 17 00:00:00 2001
From: Marius Strobl <marius@FreeBSD.org>
Date: Tue, 29 Mar 2011 19:48:03 +0000
Subject: [PATCH] Allocate memory for a DMA method table only in case we need
 to override the iommu(4) provided one, i.e. in case of Hummingbird and Sabre
 bridges, otherwise just use the iommu(4) one. This also fixes a bug
 introduced in r220039 which caused an empty DMA method table to be used for
 the second of a pair of Psycho bridges.

---
 sys/sparc64/pci/psycho.c    | 25 +++++++++++++++++--------
 sys/sparc64/pci/psychovar.h |  2 +-
 2 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/sys/sparc64/pci/psycho.c b/sys/sparc64/pci/psycho.c
index 0a3e5d594ab..2b81f272178 100644
--- a/sys/sparc64/pci/psycho.c
+++ b/sys/sparc64/pci/psycho.c
@@ -529,21 +529,29 @@ psycho_attach(device_t dev)
 		 *
 		 * For the moment, 32KB should be more than enough.
 		 */
-		memcpy(&sc->sc_dma_methods, &iommu_dma_methods,
-		    sizeof(sc->sc_dma_methods));
-		sc->sc_is = malloc(sizeof(struct iommu_state), M_DEVBUF,
-		    M_NOWAIT | M_ZERO);
+		sc->sc_is = malloc(sizeof(*sc->sc_is), M_DEVBUF, M_NOWAIT |
+		    M_ZERO);
 		if (sc->sc_is == NULL)
-			panic("%s: malloc iommu_state failed", __func__);
+			panic("%s: could not malloc IOMMU state", __func__);
 		sc->sc_is->is_flags = IOMMU_PRESERVE_PROM;
 		if (sc->sc_mode == PSYCHO_MODE_SABRE) {
-			sc->sc_dma_methods.dm_dmamap_sync =
+			sc->sc_dma_methods =
+			    malloc(sizeof(*sc->sc_dma_methods), M_DEVBUF,
+			    M_NOWAIT);
+			if (sc->sc_dma_methods == NULL)
+				panic("%s: could not malloc DMA methods",
+				    __func__);
+			memcpy(sc->sc_dma_methods, &iommu_dma_methods,
+			    sizeof(*sc->sc_dma_methods));
+			sc->sc_dma_methods->dm_dmamap_sync =
 			    sabre_dmamap_sync;
 			sc->sc_is->is_pmaxaddr =
 			    IOMMU_MAXADDR(SABRE_IOMMU_BITS);
-		} else
+		} else {
+			sc->sc_dma_methods = &iommu_dma_methods;
 			sc->sc_is->is_pmaxaddr =
 			    IOMMU_MAXADDR(PSYCHO_IOMMU_BITS);
+		}
 		sc->sc_is->is_sb[0] = sc->sc_is->is_sb[1] = 0;
 		if (OF_getproplen(node, "no-streaming-cache") < 0)
 			sc->sc_is->is_sb[0] = sc->sc_pcictl + PCR_STRBUF;
@@ -551,6 +559,7 @@ psycho_attach(device_t dev)
 		psycho_iommu_init(sc, 3, dvmabase);
 	} else {
 		/* Just copy IOMMU state, config tag and address. */
+		sc->sc_dma_methods = &iommu_dma_methods;
 		sc->sc_is = osc->sc_is;
 		if (OF_getproplen(node, "no-streaming-cache") < 0)
 			sc->sc_is->is_sb[1] = sc->sc_pcictl + PCR_STRBUF;
@@ -567,7 +576,7 @@ psycho_attach(device_t dev)
 		panic("%s: bus_dma_tag_create failed", __func__);
 	/* Customize the tag. */
 	sc->sc_pci_dmat->dt_cookie = sc->sc_is;
-	sc->sc_pci_dmat->dt_mt = &sc->sc_dma_methods;
+	sc->sc_pci_dmat->dt_mt = sc->sc_dma_methods;
 
 	i = OF_getprop(node, "bus-range", (void *)prop_array,
 	    sizeof(prop_array));
diff --git a/sys/sparc64/pci/psychovar.h b/sys/sparc64/pci/psychovar.h
index df7b8a0bfc3..117b7385aeb 100644
--- a/sys/sparc64/pci/psychovar.h
+++ b/sys/sparc64/pci/psychovar.h
@@ -36,7 +36,7 @@
  * per pair of psychos.
  */
 struct psycho_softc {
-	struct bus_dma_methods		sc_dma_methods;
+	struct bus_dma_methods		*sc_dma_methods;
 
 	device_t			sc_dev;