[PATCH v4 02/15] drivers: iommu: implement arch_{set/get}_iommu_fwspec API

From: Lorenzo Pieralisi
Date: Mon Aug 15 2016 - 11:23:59 EST


The iommu fwspec configuration mechanism currently relies on
the arch specific struct dev_archdata.iommu member to stash
the struct iommu_fwspec pointer set-up for streamid translation.

The struct dev_archdata.iommu member is arch specific and is not present
on all arches that make use of the struct iommu_fwspec infrastructure,
hence an arch specific kernel API is required to set-up and retrieve
struct iommu_fwspec pointers safely from generic iommu code, hiding
the arch specific details.

Implement the arch_{set/get}_iommu_fwspec() generic kernel infrastructure
and add the ARM/ARM64 back-end implementations.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
---
arch/arm/Kconfig | 1 +
arch/arm/include/asm/iommu-fwspec.h | 30 ++++++++++++++++++++++++++++++
arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/iommu-fwspec.h | 30 ++++++++++++++++++++++++++++++
drivers/iommu/Kconfig | 3 +++
drivers/iommu/of_iommu.c | 12 ++++++------
include/linux/of_iommu.h | 10 ++++++++++
7 files changed, 81 insertions(+), 6 deletions(-)
create mode 100644 arch/arm/include/asm/iommu-fwspec.h
create mode 100644 arch/arm64/include/asm/iommu-fwspec.h

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a9c4e48..e84f62e 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -59,6 +59,7 @@ config ARM
select HAVE_GENERIC_DMA_COHERENT
select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
select HAVE_IDE if PCI || ISA || PCMCIA
+ select HAVE_IOMMU_FWSPEC if IOMMU_API
select HAVE_IRQ_TIME_ACCOUNTING
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZ4
diff --git a/arch/arm/include/asm/iommu-fwspec.h b/arch/arm/include/asm/iommu-fwspec.h
new file mode 100644
index 0000000..2e87d8b
--- /dev/null
+++ b/arch/arm/include/asm/iommu-fwspec.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2016 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_IOMMU_FWSPEC_H
+#define __ASM_IOMMU_FWSPEC_H
+
+static inline void arch_set_iommu_fwspec(struct device *dev,
+ struct iommu_fwspec *fwspec)
+{
+ dev->archdata.iommu = fwspec;
+}
+
+static inline struct iommu_fwspec *arch_get_iommu_fwspec(struct device *dev)
+{
+ return dev->archdata.iommu;
+}
+#endif
+
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index bc3f00f..10c9b3d 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -83,6 +83,7 @@ config ARM64
select HAVE_GCC_PLUGINS
select HAVE_GENERIC_DMA_COHERENT
select HAVE_HW_BREAKPOINT if PERF_EVENTS
+ select HAVE_IOMMU_FWSPEC if IOMMU_API
select HAVE_IRQ_TIME_ACCOUNTING
select HAVE_MEMBLOCK
select HAVE_MEMBLOCK_NODE_MAP if NUMA
diff --git a/arch/arm64/include/asm/iommu-fwspec.h b/arch/arm64/include/asm/iommu-fwspec.h
new file mode 100644
index 0000000..2e87d8b
--- /dev/null
+++ b/arch/arm64/include/asm/iommu-fwspec.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2016 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_IOMMU_FWSPEC_H
+#define __ASM_IOMMU_FWSPEC_H
+
+static inline void arch_set_iommu_fwspec(struct device *dev,
+ struct iommu_fwspec *fwspec)
+{
+ dev->archdata.iommu = fwspec;
+}
+
+static inline struct iommu_fwspec *arch_get_iommu_fwspec(struct device *dev)
+{
+ return dev->archdata.iommu;
+}
+#endif
+
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 8ee54d7..101cb17 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -67,6 +67,9 @@ config OF_IOMMU
def_bool y
depends on OF && IOMMU_API

+config HAVE_IOMMU_FWSPEC
+ bool
+
# IOMMU-agnostic DMA-mapping layer
config IOMMU_DMA
bool
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index bec51eb..e30f860 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -222,7 +222,7 @@ postcore_initcall_sync(of_iommu_init);

int iommu_fwspec_init(struct device *dev, struct device_node *iommu_np)
{
- struct iommu_fwspec *fwspec = dev->archdata.iommu;
+ struct iommu_fwspec *fwspec = arch_get_iommu_fwspec(dev);

if (fwspec)
return 0;
@@ -233,13 +233,13 @@ int iommu_fwspec_init(struct device *dev, struct device_node *iommu_np)

fwspec->iommu_np = of_node_get(iommu_np);
fwspec->iommu_ops = of_iommu_get_ops(iommu_np);
- dev->archdata.iommu = fwspec;
+ arch_set_iommu_fwspec(dev, fwspec);
return 0;
}

void iommu_fwspec_free(struct device *dev)
{
- struct iommu_fwspec *fwspec = dev->archdata.iommu;
+ struct iommu_fwspec *fwspec = arch_get_iommu_fwspec(dev);

if (fwspec) {
of_node_put(fwspec->iommu_np);
@@ -249,7 +249,7 @@ void iommu_fwspec_free(struct device *dev)

int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
{
- struct iommu_fwspec *fwspec = dev->archdata.iommu;
+ struct iommu_fwspec *fwspec = arch_get_iommu_fwspec(dev);
size_t size;

if (!fwspec)
@@ -263,11 +263,11 @@ int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
while (num_ids--)
fwspec->ids[fwspec->num_ids++] = *ids++;

- dev->archdata.iommu = fwspec;
+ arch_set_iommu_fwspec(dev, fwspec);
return 0;
}

inline struct iommu_fwspec *dev_iommu_fwspec(struct device *dev)
{
- return dev->archdata.iommu;
+ return arch_get_iommu_fwspec(dev);
}
diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
index accdc05..358db49 100644
--- a/include/linux/of_iommu.h
+++ b/include/linux/of_iommu.h
@@ -46,6 +46,16 @@ void iommu_fwspec_free(struct device *dev);
int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids);
struct iommu_fwspec *dev_iommu_fwspec(struct device *dev);

+#ifdef CONFIG_HAVE_IOMMU_FWSPEC
+#include <asm/iommu-fwspec.h>
+#else /* !CONFIG_HAVE_IOMMU_FWSPEC */
+static inline void arch_set_iommu_fwspec(struct device *dev,
+ struct iommu_fwspec *fwspec) {}
+
+static inline struct iommu_fwspec *
+arch_get_iommu_fwspec(struct device *dev) { return NULL; }
+#endif
+
void of_iommu_set_ops(struct device_node *np, const struct iommu_ops *ops);
const struct iommu_ops *of_iommu_get_ops(struct device_node *np);

--
2.6.4