Add support for the _CCA method. This method indicates whether DMA is

cache-coherent or not.  To implement this, acpi(4) gets two bus_dma tags
and passes the appropriate one when attaching devices based on _CCA.
On i386/amd64, where for all practical purpose DMA is always cache-coherent,
the two tags are the same.  But on arm64 they are distinct.

ok patrick@

5 files changed, 21 insertions, 13 deletions

diff --git a/sys/arch/amd64/amd64/acpi_machdep.c b/sys/arch/amd64/amd64/acpi_machdep.c
index e41cd14a443..38cfe424770 100644
--- a/sys/arch/amd64/amd64/acpi_machdep.c
+++ b/sys/arch/amd64/amd64/acpi_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: acpi_machdep.c,v 1.89 2019/12/20 07:49:31 jsg Exp $	*/
+/*	$OpenBSD: acpi_machdep.c,v 1.90 2020/04/12 09:21:19 kettenis Exp $	*/
 /*
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
  *
@@ -96,7 +96,8 @@ acpi_attach(struct device *parent, struct device *self, void *aux)
 
 	sc->sc_iot = ba->ba_iot;
 	sc->sc_memt = ba->ba_memt;
-	sc->sc_dmat = &pci_bus_dma_tag;
+	sc->sc_cc_dmat = &pci_bus_dma_tag;
+	sc->sc_ci_dmat = &pci_bus_dma_tag;
 
 	acpi_attach_common(sc, ba->ba_acpipbase);
 }
diff --git a/sys/arch/arm64/arm64/acpi_machdep.c b/sys/arch/arm64/arm64/acpi_machdep.c
index 5343fe30934..77871e18d9a 100644
--- a/sys/arch/arm64/arm64/acpi_machdep.c
+++ b/sys/arch/arm64/arm64/acpi_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: acpi_machdep.c,v 1.3 2019/08/27 22:39:53 deraadt Exp $	*/
+/*	$OpenBSD: acpi_machdep.c,v 1.4 2020/04/12 09:21:19 kettenis Exp $	*/
 /*
  * Copyright (c) 2018 Mark Kettenis
  *
@@ -56,13 +56,14 @@ acpi_fdt_attach(struct device *parent, struct device *self, void *aux)
 	struct fdt_attach_args *faa = aux;
 	bus_dma_tag_t dmat;
 
+	sc->sc_memt = faa->fa_iot;
+	sc->sc_ci_dmat = faa->fa_dmat;
+
 	/* Create coherent DMA tag. */
-	dmat = malloc(sizeof(*sc->sc_dmat), M_DEVBUF, M_WAITOK | M_ZERO);
+	dmat = malloc(sizeof(*sc->sc_cc_dmat), M_DEVBUF, M_WAITOK | M_ZERO);
 	memcpy(dmat, faa->fa_dmat, sizeof(*dmat));
 	dmat->_flags |= BUS_DMA_COHERENT;
-	
-	sc->sc_memt = faa->fa_iot;
-	sc->sc_dmat = dmat;
+	sc->sc_cc_dmat = dmat;
 
 	acpi_attach_common(sc, faa->fa_reg[0].addr);
 }
diff --git a/sys/arch/i386/i386/acpi_machdep.c b/sys/arch/i386/i386/acpi_machdep.c
index 0e6d32de972..94281532997 100644
--- a/sys/arch/i386/i386/acpi_machdep.c
+++ b/sys/arch/i386/i386/acpi_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: acpi_machdep.c,v 1.72 2019/12/20 07:55:30 jsg Exp $	*/
+/*	$OpenBSD: acpi_machdep.c,v 1.73 2020/04/12 09:21:19 kettenis Exp $	*/
 /*
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
  *
@@ -106,7 +106,8 @@ acpi_attach(struct device *parent, struct device *self, void *aux)
 
 	sc->sc_iot = ba->ba_iot;
 	sc->sc_memt = ba->ba_memt;
-	sc->sc_dmat = &pci_bus_dma_tag;
+	sc->sc_cc_dmat = &pci_bus_dma_tag;
+	sc->sc_ci_dmat = &pci_bus_dma_tag;
 
 	acpi_attach_common(sc, ba->ba_acpipbase);
 }
diff --git a/sys/dev/acpi/acpi.c b/sys/dev/acpi/acpi.c
index 35b990dd7cf..ab5a2f09f1b 100644
--- a/sys/dev/acpi/acpi.c
+++ b/sys/dev/acpi/acpi.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: acpi.c,v 1.380 2020/04/07 13:27:51 visa Exp $ */
+/* $OpenBSD: acpi.c,v 1.381 2020/04/12 09:21:19 kettenis Exp $ */
 /*
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
  * Copyright (c) 2005 Jordan Hargrave <jordan@openbsd.org>
@@ -3122,6 +3122,7 @@ acpi_foundhid(struct aml_node *node, void *arg)
 	char		 	 dev[32];
 	struct acpi_attach_args	 aaa;
 	int64_t			 sta;
+	int64_t			 cca;
 #ifndef SMALL_KERNEL
 	int			 i;
 #endif
@@ -3133,12 +3134,15 @@ acpi_foundhid(struct aml_node *node, void *arg)
 	if ((sta & STA_PRESENT) == 0)
 		return (0);
 
+	if (aml_evalinteger(sc, node->parent, "_CCA", 0, NULL, &cca))
+		cca = 1;
+
 	acpi_attach_deps(sc, node->parent);
 
 	memset(&aaa, 0, sizeof(aaa));
 	aaa.aaa_iot = sc->sc_iot;
 	aaa.aaa_memt = sc->sc_memt;
-	aaa.aaa_dmat = sc->sc_dmat;
+	aaa.aaa_dmat = cca ? sc->sc_cc_dmat : sc->sc_ci_dmat;
 	aaa.aaa_node = node->parent;
 	aaa.aaa_dev = dev;
 	aaa.aaa_cdev = cdev;
diff --git a/sys/dev/acpi/acpivar.h b/sys/dev/acpi/acpivar.h
index 1805a2a9730..cfdc825bd23 100644
--- a/sys/dev/acpi/acpivar.h
+++ b/sys/dev/acpi/acpivar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: acpivar.h,v 1.105 2019/09/07 13:46:20 kettenis Exp $	*/
+/*	$OpenBSD: acpivar.h,v 1.106 2020/04/12 09:21:19 kettenis Exp $	*/
 /*
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
  *
@@ -208,7 +208,8 @@ struct acpi_softc {
 
 	bus_space_tag_t		sc_iot;
 	bus_space_tag_t		sc_memt;
-	bus_dma_tag_t		sc_dmat;
+	bus_dma_tag_t		sc_cc_dmat;
+	bus_dma_tag_t		sc_ci_dmat;
 
 	/*
 	 * First-level ACPI tables