From ba30109756df8f4fc4f2cc7acf3d10bf7772b1f0 Mon Sep 17 00:00:00 2001
From: patrick <patrick@openbsd.org>
Date: Sun, 28 Feb 2021 21:09:44 +0000
Subject: [PATCH] Implement IOMMU OFW API for on-SoC/non-PCI devices.

ok kettenis@
---
 sys/dev/ofw/ofw_misc.c | 45 +++++++++++++++++++++++++++++++++++++++++-
 sys/dev/ofw/ofw_misc.h |  3 ++-
 2 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/sys/dev/ofw/ofw_misc.c b/sys/dev/ofw/ofw_misc.c
index 4c89f6d6d3f..22d8d606506 100644
--- a/sys/dev/ofw/ofw_misc.c
+++ b/sys/dev/ofw/ofw_misc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ofw_misc.c,v 1.29 2021/02/26 11:28:13 kettenis Exp $	*/
+/*	$OpenBSD: ofw_misc.c,v 1.30 2021/02/28 21:09:44 patrick Exp $	*/
 /*
  * Copyright (c) 2017 Mark Kettenis
  *
@@ -871,6 +871,49 @@ iommu_device_do_map(uint32_t phandle, uint32_t *cells, bus_dma_tag_t dmat)
 	return dmat;
 }
 
+bus_dma_tag_t
+iommu_device_map(int node, bus_dma_tag_t dmat)
+{
+	uint32_t sid = 0;
+	uint32_t phandle = 0;
+	uint32_t *cell;
+	uint32_t *map;
+	int len, icells, ncells;
+
+	len = OF_getproplen(node, "iommus");
+	if (len <= 0)
+		return dmat;
+
+	map = malloc(len, M_TEMP, M_WAITOK);
+	OF_getpropintarray(node, "iommus", map, len);
+
+	cell = map;
+	ncells = len / sizeof(uint32_t);
+	while (ncells > 1) {
+		node = OF_getnodebyphandle(cell[0]);
+		if (node == 0)
+			goto out;
+
+		icells = OF_getpropint(node, "#iommu-cells", 1);
+		if (ncells < icells + 1)
+			goto out;
+
+		KASSERT(icells == 1);
+
+		phandle = cell[0];
+		sid = cell[1];
+		break;
+
+		cell += (1 + icells);
+		ncells -= (1 + icells);
+	}
+
+out:
+	free(map, M_TEMP, len);
+
+	return iommu_device_do_map(phandle, &sid, dmat);
+}
+
 bus_dma_tag_t
 iommu_device_map_pci(int node, uint32_t rid, bus_dma_tag_t dmat)
 {
diff --git a/sys/dev/ofw/ofw_misc.h b/sys/dev/ofw/ofw_misc.h
index a0cc4cbbba9..2b8659de7b4 100644
--- a/sys/dev/ofw/ofw_misc.h
+++ b/sys/dev/ofw/ofw_misc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ofw_misc.h,v 1.18 2021/02/25 22:14:54 kettenis Exp $	*/
+/*	$OpenBSD: ofw_misc.h,v 1.19 2021/02/28 21:09:44 patrick Exp $	*/
 /*
  * Copyright (c) 2017 Mark Kettenis
  *
@@ -245,6 +245,7 @@ struct iommu_device {
 };
 
 void	iommu_device_register(struct iommu_device *);
+bus_dma_tag_t iommu_device_map(int, bus_dma_tag_t);
 bus_dma_tag_t iommu_device_map_pci(int, uint32_t, bus_dma_tag_t);
 
 #endif /* _DEV_OFW_MISC_H_ */
-- 
2.20.1