[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Robin Murphy]

Hi all,

Whilst it's a long way off perfect, this has reached the point of being
functional and stable enough to be useful, so here it is. The core
consists of the meat of the arch/arm implementation modified to remove
the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
allocator instead of the bitmap-based one. For that, this series depends
on my "Genericise the IOVA allocator" series posted earlier[1].

There are plenty of obvious things still to do, including:

 * Domain and group handling is all wrong, but that's a bigger problem.
   For the moment it does more or less the same thing as the arch/arm
   code, which at least works for the one-IOMMU-per-device situation.
 * IOMMU domains and IOVA domains probably want to be better integrated
   with devices and each other, rather than having a proliferation of
   arch-specific structs.
 * The temporary map_sg implementation - I have a 'proper' iommu_map_sg
   based one in progress, but since the simple one works it's not been
   as high a priority.
 * Port arch/arm over to it. I'd guess it might be preferable to merge
   this through arm64 first, though, rather than overcomplicate matters.
 * There may well be scope for streamlining and tidying up the copied
   parts - In general I've simply avoided touching anything I don't
   fully understand.
 * In the same vein, I'm sure lots of it is fairly ARM-specific, so will
   need longer-term work to become truly generic.

[1]:http://thread.gmane.org/gmane.linux.kernel.iommu/8208

Catalin Marinas (1):
  arm64: Combine coherent and non-coherent swiotlb dma_ops

Robin Murphy (4):
  arm64: implement generic IOMMU configuration
  iommu: implement common IOMMU ops for DMA mapping
  arm64: add IOMMU dma_ops
  arm64: hook up IOMMU dma_ops

 arch/arm64/Kconfig                   |   1 +
 arch/arm64/include/asm/device.h      |   3 +
 arch/arm64/include/asm/dma-mapping.h |  33 +--
 arch/arm64/kernel/setup.c            |   2 +
 arch/arm64/mm/dma-mapping.c          | 435 ++++++++++++++++++++++++++++-----
 include/linux/dma-iommu.h            |  78 ++++++
 lib/Kconfig                          |   8 +
 lib/Makefile                         |   1 +
 lib/dma-iommu.c                      | 455 +++++++++++++++++++++++++++++++++++
 9 files changed, 938 insertions(+), 78 deletions(-)
 create mode 100644 include/linux/dma-iommu.h
 create mode 100644 lib/dma-iommu.c

-- 
1.9.1

[RFC PATCH 1/5] arm64: Combine coherent and non-coherent swiotlb dma_ops

[Robin Murphy]

From: Catalin Marinas <catalin.marinas@arm.com>

Since dev_archdata now has a dma_coherent state, combine the two
coherent and non-coherent operations and remove their declaration,
together with set_dma_ops, from the arch dma-mapping.h file.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
 arch/arm64/include/asm/dma-mapping.h |  11 +---
 arch/arm64/mm/dma-mapping.c          | 116 ++++++++++++++++-------------------
 2 files changed, 54 insertions(+), 73 deletions(-)

diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
index 9ce3e68..6932bb5 100644
--- a/arch/arm64/include/asm/dma-mapping.h
+++ b/arch/arm64/include/asm/dma-mapping.h
@@ -28,8 +28,6 @@
 
 #define DMA_ERROR_CODE	(~(dma_addr_t)0)
 extern struct dma_map_ops *dma_ops;
-extern struct dma_map_ops coherent_swiotlb_dma_ops;
-extern struct dma_map_ops noncoherent_swiotlb_dma_ops;
 
 static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
 {
@@ -47,23 +45,18 @@ static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 		return __generic_dma_ops(dev);
 }
 
-static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
-{
-	dev->archdata.dma_ops = ops;
-}
-
 static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 				      struct iommu_ops *iommu, bool coherent)
 {
 	dev->archdata.dma_coherent = coherent;
-	if (coherent)
-		set_dma_ops(dev, &coherent_swiotlb_dma_ops);
 }
 #define arch_setup_dma_ops	arch_setup_dma_ops
 
 /* do not use this function in a driver */
 static inline bool is_device_dma_coherent(struct device *dev)
 {
+	if (!dev)
+		return false;
 	return dev->archdata.dma_coherent;
 }
 
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index d920942..0a24b9b 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -134,16 +134,17 @@ static void __dma_free_coherent(struct device *dev, size_t size,
 		swiotlb_free_coherent(dev, size, vaddr, dma_handle);
 }
 
-static void *__dma_alloc_noncoherent(struct device *dev, size_t size,
-				     dma_addr_t *dma_handle, gfp_t flags,
-				     struct dma_attrs *attrs)
+static void *__dma_alloc(struct device *dev, size_t size,
+			 dma_addr_t *dma_handle, gfp_t flags,
+			 struct dma_attrs *attrs)
 {
 	struct page *page;
 	void *ptr, *coherent_ptr;
+	bool coherent = is_device_dma_coherent(dev);
 
 	size = PAGE_ALIGN(size);
 
-	if (!(flags & __GFP_WAIT)) {
+	if (!coherent && !(flags & __GFP_WAIT)) {
 		struct page *page = NULL;
 		void *addr = __alloc_from_pool(size, &page);
 
@@ -151,13 +152,16 @@ static void *__dma_alloc_noncoherent(struct device *dev, size_t size,
 			*dma_handle = phys_to_dma(dev, page_to_phys(page));
 
 		return addr;
-
 	}
 
 	ptr = __dma_alloc_coherent(dev, size, dma_handle, flags, attrs);
 	if (!ptr)
 		goto no_mem;
 
+	/* no need for non-cacheable mapping if coherent */
+	if (coherent)
+		return ptr;
+
 	/* remove any dirty cache lines on the kernel alias */
 	__dma_flush_range(ptr, ptr + size);
 
@@ -179,15 +183,17 @@ no_mem:
 	return NULL;
 }
 
-static void __dma_free_noncoherent(struct device *dev, size_t size,
-				   void *vaddr, dma_addr_t dma_handle,
-				   struct dma_attrs *attrs)
+static void __dma_free(struct device *dev, size_t size,
+		       void *vaddr, dma_addr_t dma_handle,
+		       struct dma_attrs *attrs)
 {
 	void *swiotlb_addr = phys_to_virt(dma_to_phys(dev, dma_handle));
 
-	if (__free_from_pool(vaddr, size))
-		return;
-	vunmap(vaddr);
+	if (!is_device_dma_coherent(dev)) {
+		if (__free_from_pool(vaddr, size))
+			return;
+		vunmap(vaddr);
+	}
 	__dma_free_coherent(dev, size, swiotlb_addr, dma_handle, attrs);
 }
 
@@ -199,7 +205,8 @@ static dma_addr_t __swiotlb_map_page(struct device *dev, struct page *page,
 	dma_addr_t dev_addr;
 
 	dev_addr = swiotlb_map_page(dev, page, offset, size, dir, attrs);
-	__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
+	if (!is_device_dma_coherent(dev))
+		__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 
 	return dev_addr;
 }
@@ -209,7 +216,8 @@ static void __swiotlb_unmap_page(struct device *dev, dma_addr_t dev_addr,
 				 size_t size, enum dma_data_direction dir,
 				 struct dma_attrs *attrs)
 {
-	__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
+	if (!is_device_dma_coherent(dev))
+		__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 	swiotlb_unmap_page(dev, dev_addr, size, dir, attrs);
 }
 
@@ -221,9 +229,10 @@ static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
 	int i, ret;
 
 	ret = swiotlb_map_sg_attrs(dev, sgl, nelems, dir, attrs);
-	for_each_sg(sgl, sg, ret, i)
-		__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
-			       sg->length, dir);
+	if (!is_device_dma_coherent(dev))
+		for_each_sg(sgl, sg, ret, i)
+			__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
+				       sg->length, dir);
 
 	return ret;
 }
@@ -236,9 +245,10 @@ static void __swiotlb_unmap_sg_attrs(struct device *dev,
 	struct scatterlist *sg;
 	int i;
 
-	for_each_sg(sgl, sg, nelems, i)
-		__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
-				 sg->length, dir);
+	if (!is_device_dma_coherent(dev))
+		for_each_sg(sgl, sg, nelems, i)
+			__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
+					 sg->length, dir);
 	swiotlb_unmap_sg_attrs(dev, sgl, nelems, dir, attrs);
 }
 
@@ -246,7 +256,8 @@ static void __swiotlb_sync_single_for_cpu(struct device *dev,
 					  dma_addr_t dev_addr, size_t size,
 					  enum dma_data_direction dir)
 {
-	__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
+	if (!is_device_dma_coherent(dev))
+		__dma_unmap_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 	swiotlb_sync_single_for_cpu(dev, dev_addr, size, dir);
 }
 
@@ -255,7 +266,8 @@ static void __swiotlb_sync_single_for_device(struct device *dev,
 					     enum dma_data_direction dir)
 {
 	swiotlb_sync_single_for_device(dev, dev_addr, size, dir);
-	__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
+	if (!is_device_dma_coherent(dev))
+		__dma_map_area(phys_to_virt(dma_to_phys(dev, dev_addr)), size, dir);
 }
 
 static void __swiotlb_sync_sg_for_cpu(struct device *dev,
@@ -265,9 +277,10 @@ static void __swiotlb_sync_sg_for_cpu(struct device *dev,
 	struct scatterlist *sg;
 	int i;
 
-	for_each_sg(sgl, sg, nelems, i)
-		__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
-				 sg->length, dir);
+	if (!is_device_dma_coherent(dev))
+		for_each_sg(sgl, sg, nelems, i)
+			__dma_unmap_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
+					 sg->length, dir);
 	swiotlb_sync_sg_for_cpu(dev, sgl, nelems, dir);
 }
 
@@ -279,9 +292,10 @@ static void __swiotlb_sync_sg_for_device(struct device *dev,
 	int i;
 
 	swiotlb_sync_sg_for_device(dev, sgl, nelems, dir);
-	for_each_sg(sgl, sg, nelems, i)
-		__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
-			       sg->length, dir);
+	if (!is_device_dma_coherent(dev))
+		for_each_sg(sgl, sg, nelems, i)
+			__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
+				       sg->length, dir);
 }
 
 /* vma->vm_page_prot must be set appropriately before calling this function */
@@ -308,28 +322,20 @@ static int __dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
 	return ret;
 }
 
-static int __swiotlb_mmap_noncoherent(struct device *dev,
-		struct vm_area_struct *vma,
-		void *cpu_addr, dma_addr_t dma_addr, size_t size,
-		struct dma_attrs *attrs)
-{
-	vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot, false);
-	return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
-}
-
-static int __swiotlb_mmap_coherent(struct device *dev,
-		struct vm_area_struct *vma,
-		void *cpu_addr, dma_addr_t dma_addr, size_t size,
-		struct dma_attrs *attrs)
+static int __swiotlb_mmap(struct device *dev,
+			  struct vm_area_struct *vma,
+			  void *cpu_addr, dma_addr_t dma_addr, size_t size,
+			  struct dma_attrs *attrs)
 {
-	/* Just use whatever page_prot attributes were specified */
+	vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot,
+					     is_device_dma_coherent(dev));
 	return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
 }
 
-struct dma_map_ops noncoherent_swiotlb_dma_ops = {
-	.alloc = __dma_alloc_noncoherent,
-	.free = __dma_free_noncoherent,
-	.mmap = __swiotlb_mmap_noncoherent,
+static struct dma_map_ops swiotlb_dma_ops = {
+	.alloc = __dma_alloc,
+	.free = __dma_free,
+	.mmap = __swiotlb_mmap,
 	.map_page = __swiotlb_map_page,
 	.unmap_page = __swiotlb_unmap_page,
 	.map_sg = __swiotlb_map_sg_attrs,
@@ -341,24 +347,6 @@ struct dma_map_ops noncoherent_swiotlb_dma_ops = {
 	.dma_supported = swiotlb_dma_supported,
 	.mapping_error = swiotlb_dma_mapping_error,
 };
-EXPORT_SYMBOL(noncoherent_swiotlb_dma_ops);
-
-struct dma_map_ops coherent_swiotlb_dma_ops = {
-	.alloc = __dma_alloc_coherent,
-	.free = __dma_free_coherent,
-	.mmap = __swiotlb_mmap_coherent,
-	.map_page = swiotlb_map_page,
-	.unmap_page = swiotlb_unmap_page,
-	.map_sg = swiotlb_map_sg_attrs,
-	.unmap_sg = swiotlb_unmap_sg_attrs,
-	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
-	.sync_single_for_device = swiotlb_sync_single_for_device,
-	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
-	.sync_sg_for_device = swiotlb_sync_sg_for_device,
-	.dma_supported = swiotlb_dma_supported,
-	.mapping_error = swiotlb_dma_mapping_error,
-};
-EXPORT_SYMBOL(coherent_swiotlb_dma_ops);
 
 extern int swiotlb_late_init_with_default_size(size_t default_size);
 
@@ -427,7 +415,7 @@ static int __init swiotlb_late_init(void)
 {
 	size_t swiotlb_size = min(SZ_64M, MAX_ORDER_NR_PAGES << PAGE_SHIFT);
 
-	dma_ops = &noncoherent_swiotlb_dma_ops;
+	dma_ops = &swiotlb_dma_ops;
 
 	return swiotlb_late_init_with_default_size(swiotlb_size);
 }
-- 
1.9.1

[RFC PATCH 2/5] arm64: implement generic IOMMU configuration

[Robin Murphy]

Add the necessary call to of_iommu_init.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 arch/arm64/kernel/setup.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index b809911..8304141 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -40,6 +40,7 @@
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
 #include <linux/memblock.h>
+#include <linux/of_iommu.h>
 #include <linux/of_fdt.h>
 #include <linux/of_platform.h>
 #include <linux/efi.h>
@@ -424,6 +425,7 @@ void __init setup_arch(char **cmdline_p)
 
 static int __init arm64_device_init(void)
 {
+	of_iommu_init();
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 	return 0;
 }
-- 
1.9.1

[RFC PATCH 3/5] iommu: implement common IOMMU ops for DMA mapping

[Robin Murphy]

Taking inspiration from the existing arch/arm code, break out some
generic functions to interface the DMA-API to the IOMMU-API. This will
do the bulk of the heavy lifting for IOMMU-backed dma-mapping.

Whilst the target is arm64, rather than introduce yet another private
implementation, place this in common code as the first step towards
consolidating the numerous versions spread around between architecture
code and IOMMU drivers.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 include/linux/dma-iommu.h |  78 ++++++++
 lib/Kconfig               |   8 +
 lib/Makefile              |   1 +
 lib/dma-iommu.c           | 455 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 542 insertions(+)
 create mode 100644 include/linux/dma-iommu.h
 create mode 100644 lib/dma-iommu.c

diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
new file mode 100644
index 0000000..4515407
--- /dev/null
+++ b/include/linux/dma-iommu.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2014 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 __DMA_IOMMU_H
+#define __DMA_IOMMU_H
+
+#ifdef __KERNEL__
+
+#include <linux/types.h>
+#include <linux/iommu.h>
+
+#ifdef CONFIG_IOMMU_DMA
+
+int iommu_dma_init(void);
+
+struct iommu_dma_mapping *iommu_dma_create_mapping(struct iommu_ops *ops,
+		dma_addr_t base, size_t size);
+void iommu_dma_release_mapping(struct iommu_dma_mapping *mapping);
+
+dma_addr_t iommu_dma_create_iova_mapping(struct device *dev,
+		struct page **pages, size_t size, bool coherent);
+int iommu_dma_release_iova_mapping(struct device *dev, dma_addr_t iova,
+		size_t size);
+
+struct page **iommu_dma_alloc_buffer(struct device *dev, size_t size,
+		gfp_t gfp, struct dma_attrs *attrs,
+		void (clear_buffer)(struct page *page, size_t size));
+int iommu_dma_free_buffer(struct device *dev, struct page **pages, size_t size,
+		struct dma_attrs *attrs);
+
+dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		struct dma_attrs *attrs);
+dma_addr_t iommu_dma_coherent_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		struct dma_attrs *attrs);
+void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
+		enum dma_data_direction dir, struct dma_attrs *attrs);
+
+int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+		enum dma_data_direction dir, struct dma_attrs *attrs);
+int iommu_dma_coherent_map_sg(struct device *dev, struct scatterlist *sg,
+		int nents, enum dma_data_direction dir,
+		struct dma_attrs *attrs);
+void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sgl, int nents,
+		enum dma_data_direction dir, struct dma_attrs *attrs);
+
+int iommu_dma_attach_device(struct device *dev, struct iommu_dma_mapping *mapping);
+void iommu_dma_detach_device(struct device *dev);
+
+int iommu_dma_supported(struct device *hwdev, u64 mask);
+int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
+
+phys_addr_t iova_to_phys(struct device *dev, dma_addr_t dev_addr);
+
+#else
+
+static inline phys_addr_t iova_to_phys(struct device *dev, dma_addr_t dev_addr)
+{
+	return 0;
+}
+
+#endif  /* CONFIG_IOMMU_DMA */
+
+#endif	/* __KERNEL__ */
+#endif	/* __DMA_IOMMU_H */
diff --git a/lib/Kconfig b/lib/Kconfig
index 54cf309..965d027 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -518,4 +518,12 @@ source "lib/fonts/Kconfig"
 config ARCH_HAS_SG_CHAIN
 	def_bool n
 
+#
+# IOMMU-agnostic DMA-mapping layer
+#
+config IOMMU_DMA
+	def_bool n
+	depends on IOMMU_SUPPORT && ARCH_HAS_SG_CHAIN && NEED_SG_DMA_LENGTH
+	select IOMMU_IOVA
+
 endmenu
diff --git a/lib/Makefile b/lib/Makefile
index 3c3b30b..e4b6134 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -103,6 +103,7 @@ obj-$(CONFIG_AUDIT_COMPAT_GENERIC) += compat_audit.o
 
 obj-$(CONFIG_SWIOTLB) += swiotlb.o
 obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o
+obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
 obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o
 obj-$(CONFIG_NOTIFIER_ERROR_INJECTION) += notifier-error-inject.o
 obj-$(CONFIG_CPU_NOTIFIER_ERROR_INJECT) += cpu-notifier-error-inject.o
diff --git a/lib/dma-iommu.c b/lib/dma-iommu.c
new file mode 100644
index 0000000..2fb77b3
--- /dev/null
+++ b/lib/dma-iommu.c
@@ -0,0 +1,455 @@
+/*
+ * A fairly generic DMA-API to IOMMU-API glue layer.
+ *
+ * Copyright (C) 2014 ARM Ltd.
+ *
+ * based in part on arch/arm/mm/dma-mapping.c:
+ * Copyright (C) 2000-2004 Russell King
+ *
+ * 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/>.
+ */
+
+#define pr_fmt(fmt)	"%s: " fmt, __func__
+
+#include <linux/dma-contiguous.h>
+#include <linux/dma-iommu.h>
+#include <linux/iova.h>
+
+int iommu_dma_init(void)
+{
+	return iommu_iova_cache_init();
+}
+
+struct iommu_dma_mapping {
+	struct iommu_domain *domain;
+	struct iova_domain *iovad;
+	struct kref kref;
+};
+
+static inline struct iommu_domain *dev_domain(struct device *dev)
+{
+	return dev->archdata.mapping->domain;
+}
+
+static inline struct iova_domain *dev_iovad(struct device *dev)
+{
+	return dev->archdata.mapping->iovad;
+}
+
+phys_addr_t iova_to_phys(struct device *dev, dma_addr_t dev_addr)
+{
+	return iommu_iova_to_phys(dev_domain(dev), dev_addr);
+}
+
+static int __dma_direction_to_prot(enum dma_data_direction dir, bool coherent)
+{
+	int prot = coherent ? IOMMU_CACHE : 0;
+
+	switch (dir) {
+	case DMA_BIDIRECTIONAL:
+		return prot | IOMMU_READ | IOMMU_WRITE;
+	case DMA_TO_DEVICE:
+		return prot | IOMMU_READ;
+	case DMA_FROM_DEVICE:
+		return prot | IOMMU_WRITE;
+	default:
+		return 0;
+	}
+}
+
+static struct iova *__alloc_iova(struct device *dev, size_t size, bool coherent)
+{
+	struct iova_domain *iovad = dev_iovad(dev);
+	unsigned long shift = iova_shift(iovad);
+	unsigned long length = iova_align(iovad, size) >> shift;
+	u64 dma_limit;
+
+	if (coherent)
+		dma_limit = dev->coherent_dma_mask;
+	else
+		dma_limit = *dev->dma_mask;
+	/* Alignment should probably come from a domain/device attribute... */
+	return alloc_iova(iovad, length, dma_limit >> shift, false);
+}
+
+/*
+ * Create a mapping in device IO address space for specified pages
+ */
+dma_addr_t iommu_dma_create_iova_mapping(struct device *dev,
+			struct page **pages, size_t size, bool coherent)
+{
+	struct iommu_domain *domain = dev_domain(dev);
+	struct iova_domain *iovad = dev_iovad(dev);
+	struct iova *iova;
+	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	dma_addr_t addr_lo, addr_hi;
+	int i, prot = __dma_direction_to_prot(DMA_BIDIRECTIONAL, coherent);
+
+	iova = __alloc_iova(dev, size, coherent);
+	if (!iova)
+		return DMA_ERROR_CODE;
+
+	addr_hi = addr_lo = iova_dma_addr(iovad, iova);
+	for (i = 0; i < count; ) {
+		unsigned int next_pfn = page_to_pfn(pages[i]) + 1;
+		phys_addr_t phys = page_to_phys(pages[i]);
+		unsigned int len, j;
+
+		for (j = i+1; j < count; j++, next_pfn++)
+			if (page_to_pfn(pages[j]) != next_pfn)
+				break;
+
+		len = (j - i) << PAGE_SHIFT;
+		if (iommu_map(domain, addr_hi, phys, len, prot))
+			goto fail;
+		addr_hi += len;
+		i = j;
+	}
+	return addr_lo;
+fail:
+	iommu_unmap(domain, addr_lo, addr_hi - addr_lo);
+	__free_iova(iovad, iova);
+	return DMA_ERROR_CODE;
+}
+
+int iommu_dma_release_iova_mapping(struct device *dev, dma_addr_t iova,
+				   size_t size)
+{
+	struct iommu_domain *domain = dev_domain(dev);
+	struct iova_domain *iovad = dev_iovad(dev);
+	size_t offset = iova_offset(iovad, iova);
+
+	iommu_unmap(domain, iova - offset, iova_align(iovad, size + offset));
+	free_iova(iovad, iova_pfn(iovad, iova));
+	return 0;
+}
+
+struct page **iommu_dma_alloc_buffer(struct device *dev, size_t size,
+		gfp_t gfp, struct dma_attrs *attrs,
+		void (clear_buffer)(struct page *page, size_t size))
+{
+	struct page **pages;
+	int count = size >> PAGE_SHIFT;
+	int array_size = count * sizeof(struct page *);
+	int i = 0;
+
+	if (array_size <= PAGE_SIZE)
+		pages = kzalloc(array_size, GFP_KERNEL);
+	else
+		pages = vzalloc(array_size);
+	if (!pages)
+		return NULL;
+
+	if (dma_get_attr(DMA_ATTR_FORCE_CONTIGUOUS, attrs)) {
+		unsigned long order = get_order(size);
+		struct page *page;
+
+		page = dma_alloc_from_contiguous(dev, count, order);
+		if (!page)
+			goto error;
+
+		if (clear_buffer)
+			clear_buffer(page, size);
+
+		for (i = 0; i < count; i++)
+			pages[i] = page + i;
+
+		return pages;
+	}
+
+	/*
+	 * IOMMU can map any pages, so himem can also be used here
+	 */
+	gfp |= __GFP_NOWARN | __GFP_HIGHMEM;
+
+	while (count) {
+		int j, order = __fls(count);
+
+		pages[i] = alloc_pages(gfp, order);
+		while (!pages[i] && order)
+			pages[i] = alloc_pages(gfp, --order);
+		if (!pages[i])
+			goto error;
+
+		if (order) {
+			split_page(pages[i], order);
+			j = 1 << order;
+			while (--j)
+				pages[i + j] = pages[i] + j;
+		}
+
+		if (clear_buffer)
+			clear_buffer(pages[i], PAGE_SIZE << order);
+		i += 1 << order;
+		count -= 1 << order;
+	}
+
+	return pages;
+error:
+	while (i--)
+		if (pages[i])
+			__free_pages(pages[i], 0);
+	if (array_size <= PAGE_SIZE)
+		kfree(pages);
+	else
+		vfree(pages);
+	return NULL;
+}
+
+int iommu_dma_free_buffer(struct device *dev, struct page **pages, size_t size,
+		struct dma_attrs *attrs)
+{
+	int count = size >> PAGE_SHIFT;
+	int array_size = count * sizeof(struct page *);
+	int i;
+
+	if (dma_get_attr(DMA_ATTR_FORCE_CONTIGUOUS, attrs)) {
+		dma_release_from_contiguous(dev, pages[0], count);
+	} else {
+		for (i = 0; i < count; i++)
+			if (pages[i])
+				__free_pages(pages[i], 0);
+	}
+
+	if (array_size <= PAGE_SIZE)
+		kfree(pages);
+	else
+		vfree(pages);
+	return 0;
+}
+
+static dma_addr_t __iommu_dma_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		bool coherent)
+{
+	dma_addr_t dma_addr;
+	struct iommu_domain *domain = dev_domain(dev);
+	struct iova_domain *iovad = dev_iovad(dev);
+	phys_addr_t phys = page_to_phys(page) + offset;
+	size_t iova_off = iova_offset(iovad, phys);
+	size_t len = iova_align(iovad, size + iova_off);
+	int prot = __dma_direction_to_prot(dir, coherent);
+	struct iova *iova = __alloc_iova(dev, len, coherent);
+
+	if (!iova)
+		return DMA_ERROR_CODE;
+
+	dma_addr = iova_dma_addr(iovad, iova);
+	if (iommu_map(domain, dma_addr, phys - iova_off, len, prot)) {
+		__free_iova(iovad, iova);
+		return DMA_ERROR_CODE;
+	}
+
+	return dma_addr + iova_off;
+}
+
+dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		struct dma_attrs *attrs)
+{
+	return __iommu_dma_map_page(dev, page, offset, size, dir, false);
+}
+
+dma_addr_t iommu_dma_coherent_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		struct dma_attrs *attrs)
+{
+	return __iommu_dma_map_page(dev, page, offset, size, dir, true);
+}
+
+void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
+		enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+	struct iommu_domain *domain = dev_domain(dev);
+	struct iova_domain *iovad = dev_iovad(dev);
+	size_t offset = iova_offset(iovad, handle);
+	size_t len = iova_align(iovad, size + offset);
+	dma_addr_t iova = handle - offset;
+
+	if (!iova)
+		return;
+
+	iommu_unmap(domain, iova, len);
+	free_iova(iovad, iova_pfn(iovad, iova));
+}
+
+/*
+ * This little guy is filling in until iommu_map_sg lands and we can hook that
+ * up instead (which is going to be rather involved thanks to page alignment)
+ */
+static int __iommu_dma_map_sg_simple(struct device *dev, struct scatterlist *sg,
+		int nents, enum dma_data_direction dir, struct dma_attrs *attrs,
+		bool coherent)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i) {
+		sg_dma_address(s) = __iommu_dma_map_page(dev, sg_page(s), s->offset,
+						s->length, dir, coherent);
+		sg_dma_len(s) = s->length;
+	}
+	return nents;
+}
+
+int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+		enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+	return __iommu_dma_map_sg_simple(dev, sg, nents, dir, attrs, false);
+}
+
+int iommu_dma_coherent_map_sg(struct device *dev, struct scatterlist *sg,
+		int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+	return __iommu_dma_map_sg_simple(dev, sg, nents, dir, attrs, true);
+}
+
+void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+		enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i)
+		if (sg_dma_len(s))
+			iommu_dma_unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir, attrs);
+}
+
+struct iommu_dma_mapping *iommu_dma_create_mapping(struct iommu_ops *ops,
+		dma_addr_t base, size_t size)
+{
+	struct iommu_dma_mapping *mapping;
+	struct iommu_domain *domain;
+	struct iova_domain *iovad;
+	struct iommu_domain_geometry *dg;
+	unsigned long order, base_pfn, end_pfn;
+
+	pr_debug("base=%pad\tsize=0x%zx\n", &base, size);
+	mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
+	if (!mapping)
+		return NULL;
+
+	/*
+	 * HACK: We'd like to ask the relevant IOMMU in ops for a suitable
+	 * domain, but until that happens, bypass the bus nonsense and create
+	 * one directly for this specific device/IOMMU combination...
+	 */
+	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+
+	if (!domain)
+		goto out_free_mapping;
+	domain->ops = ops;
+
+	if (ops->domain_init(domain))
+		goto out_free_mapping;
+	/*
+	 * ...and do the bare minimum to sanity-check that the domain allows
+	 * at least some access to the device...
+	 */
+	dg = &domain->geometry;
+	if (!(base < dg->aperture_end && base + size > dg->aperture_start)) {
+		pr_warn("DMA range outside IOMMU capability; is DT correct?\n");
+		goto out_free_mapping;
+	}
+	/* ...then finally give it a kicking to make sure it fits */
+	dg->aperture_start = max(base, dg->aperture_start);
+	dg->aperture_end = min(base + size - 1, dg->aperture_end);
+	/*
+	 * Note that this specifically breaks the case where multiple devices
+	 * need to share a domain, but we don't have the necessary information
+	 * to handle that here anyway - "proper" group and domain allocation
+	 * needs to involve the IOMMU driver and a complete view of the bus.
+	 */
+
+	iovad = kzalloc(sizeof(*iovad), GFP_KERNEL);
+	if (!iovad)
+		goto out_free_domain;
+
+	/* Use the smallest supported page size for IOVA granularity */
+	order = __ffs(ops->pgsize_bitmap);
+	base_pfn = max(dg->aperture_start >> order, (dma_addr_t)1);
+	end_pfn = dg->aperture_end >> order;
+	init_iova_domain(iovad, 1UL << order, base_pfn, end_pfn);
+
+	mapping->domain = domain;
+	mapping->iovad = iovad;
+	kref_init(&mapping->kref);
+	pr_debug("mapping %p created\n", mapping);
+	return mapping;
+
+out_free_domain:
+	iommu_domain_free(domain);
+out_free_mapping:
+	kfree(mapping);
+	return NULL;
+}
+
+static void iommu_dma_free_mapping(struct kref *kref)
+{
+	struct iommu_dma_mapping *mapping;
+
+	mapping = container_of(kref, struct iommu_dma_mapping, kref);
+	put_iova_domain(mapping->iovad);
+	iommu_domain_free(mapping->domain);
+	kfree(mapping);
+	pr_debug("mapping: %p freed\n", mapping);
+}
+
+void iommu_dma_release_mapping(struct iommu_dma_mapping *mapping)
+{
+	kref_put(&mapping->kref, iommu_dma_free_mapping);
+}
+
+void iommu_dma_detach_device(struct device *dev)
+{
+	struct iommu_dma_mapping *mapping = dev->archdata.mapping;
+
+	if (!mapping) {
+		dev_warn(dev, "Not attached\n");
+		return;
+	}
+	dev->archdata.mapping = NULL;
+	iommu_detach_device(mapping->domain, dev);
+	iommu_dma_release_mapping(mapping);
+	pr_debug("%s detached from mapping: %p\n", dev_name(dev), mapping);
+}
+
+int iommu_dma_attach_device(struct device *dev, struct iommu_dma_mapping *mapping)
+{
+	int ret;
+
+	kref_get(&mapping->kref);
+	ret = iommu_attach_device(mapping->domain, dev);
+	if (ret)
+		iommu_dma_release_mapping(mapping);
+	else
+		dev->archdata.mapping = mapping;
+	pr_debug("%s%s attached to mapping: %p\n", dev_name(dev),
+			ret?" *not*":"", mapping);
+	return ret;
+}
+
+int iommu_dma_supported(struct device *hwdev, u64 mask)
+{
+	/*
+	 * This looks awful, but really it's reasonable to assume that if an
+	 * IOMMU can't address everything that the CPU can, it probably isn't
+	 * generic enough to be using this implementation in the first place.
+	 */
+	return 1;
+}
+
+int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+	return dma_addr == DMA_ERROR_CODE;
+}
-- 
1.9.1

[RFC PATCH 3/5] iommu: implement common IOMMU ops for DMA mapping

[Laura Abbott]

On 1/12/2015 12:48 PM, Robin Murphy wrote:
> Taking inspiration from the existing arch/arm code, break out some
> generic functions to interface the DMA-API to the IOMMU-API. This will
> do the bulk of the heavy lifting for IOMMU-backed dma-mapping.
>
> Whilst the target is arm64, rather than introduce yet another private
> implementation, place this in common code as the first step towards
> consolidating the numerous versions spread around between architecture
> code and IOMMU drivers.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   include/linux/dma-iommu.h |  78 ++++++++
>   lib/Kconfig               |   8 +
>   lib/Makefile              |   1 +
>   lib/dma-iommu.c           | 455 ++++++++++++++++++++++++++++++++++++++++++++++
>   4 files changed, 542 insertions(+)
>   create mode 100644 include/linux/dma-iommu.h
>   create mode 100644 lib/dma-iommu.c
>
> diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
> new file mode 100644
> index 0000000..4515407
> --- /dev/null
> +++ b/include/linux/dma-iommu.h
<snip>
> +
> +struct iommu_dma_mapping *iommu_dma_create_mapping(struct iommu_ops *ops,
> +		dma_addr_t base, size_t size)
> +{
> +	struct iommu_dma_mapping *mapping;
> +	struct iommu_domain *domain;
> +	struct iova_domain *iovad;
> +	struct iommu_domain_geometry *dg;
> +	unsigned long order, base_pfn, end_pfn;
> +
> +	pr_debug("base=%pad\tsize=0x%zx\n", &base, size);
> +	mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
> +	if (!mapping)
> +		return NULL;
> +
> +	/*
> +	 * HACK: We'd like to ask the relevant IOMMU in ops for a suitable
> +	 * domain, but until that happens, bypass the bus nonsense and create
> +	 * one directly for this specific device/IOMMU combination...
> +	 */
> +	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
> +
> +	if (!domain)
> +		goto out_free_mapping;
> +	domain->ops = ops;
> +
> +	if (ops->domain_init(domain))
> +		goto out_free_mapping;
> +	/*
> +	 * ...and do the bare minimum to sanity-check that the domain allows
> +	 * at least some access to the device...
> +	 */
> +	dg = &domain->geometry;
> +	if (!(base < dg->aperture_end && base + size > dg->aperture_start)) {
> +		pr_warn("DMA range outside IOMMU capability; is DT correct?\n");
> +		goto out_free_mapping;
> +	}

This check seems to always fail with base = 0 because dg->aperture_end is
always going to be 0 as well. base <= dg->aperature_end ?

Thanks,
Laura


-- 
Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

[RFC PATCH 3/5] iommu: implement common IOMMU ops for DMA mapping

[Robin Murphy]

Hi Laura,

Thanks for looking

On 23/01/15 17:42, Laura Abbott wrote:
> On 1/12/2015 12:48 PM, Robin Murphy wrote:
>> Taking inspiration from the existing arch/arm code, break out some
>> generic functions to interface the DMA-API to the IOMMU-API. This will
>> do the bulk of the heavy lifting for IOMMU-backed dma-mapping.
>>
>> Whilst the target is arm64, rather than introduce yet another private
>> implementation, place this in common code as the first step towards
>> consolidating the numerous versions spread around between architecture
>> code and IOMMU drivers.
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>>    include/linux/dma-iommu.h |  78 ++++++++
>>    lib/Kconfig               |   8 +
>>    lib/Makefile              |   1 +
>>    lib/dma-iommu.c           | 455 ++++++++++++++++++++++++++++++++++++++++++++++
>>    4 files changed, 542 insertions(+)
>>    create mode 100644 include/linux/dma-iommu.h
>>    create mode 100644 lib/dma-iommu.c
>>
>> diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
>> new file mode 100644
>> index 0000000..4515407
>> --- /dev/null
>> +++ b/include/linux/dma-iommu.h
> <snip>
>> +
>> +struct iommu_dma_mapping *iommu_dma_create_mapping(struct iommu_ops *ops,
>> +		dma_addr_t base, size_t size)
>> +{
>> +	struct iommu_dma_mapping *mapping;
>> +	struct iommu_domain *domain;
>> +	struct iova_domain *iovad;
>> +	struct iommu_domain_geometry *dg;
>> +	unsigned long order, base_pfn, end_pfn;
>> +
>> +	pr_debug("base=%pad\tsize=0x%zx\n", &base, size);
>> +	mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
>> +	if (!mapping)
>> +		return NULL;
>> +
>> +	/*
>> +	 * HACK: We'd like to ask the relevant IOMMU in ops for a suitable
>> +	 * domain, but until that happens, bypass the bus nonsense and create
>> +	 * one directly for this specific device/IOMMU combination...
>> +	 */
>> +	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
>> +
>> +	if (!domain)
>> +		goto out_free_mapping;
>> +	domain->ops = ops;
>> +
>> +	if (ops->domain_init(domain))
>> +		goto out_free_mapping;
>> +	/*
>> +	 * ...and do the bare minimum to sanity-check that the domain allows
>> +	 * at least some access to the device...
>> +	 */
>> +	dg = &domain->geometry;
>> +	if (!(base < dg->aperture_end && base + size > dg->aperture_start)) {
>> +		pr_warn("DMA range outside IOMMU capability; is DT correct?\n");
>> +		goto out_free_mapping;
>> +	}
>
> This check seems to always fail with base = 0 because dg->aperture_end is
> always going to be 0 as well. base <= dg->aperature_end ?
>

Strictly you're right, since aperture_end should be the highest mappable 
address thus you could create a valid, if a little silly, 1-byte domain 
if both were zero. However, it shouldn't really be zero.

I put this bit in since the majority of IOMMU drivers set up the 
geometry in domain_init and it seemed worth making use of. The ARM SMMU 
driver is currently one of the odd ones out that don't, however one of 
my as-yet-unpublished patches porting it to the new of_iommu_configure 
framework involves fixing domain initialisation and adds geometry setup 
as well - that's what I've been testing with. I'm hoping to get that 
series out soon, but among other things it needs a messy merge with 
Will's pagetable changes.

Robin.

[RFC PATCH 3/5] iommu: implement common IOMMU ops for DMA mapping

[Joerg Roedel]

Hi Robin,

thanks for the patch, I think it is good start to move forward. See my
comments below.

On Mon, Jan 12, 2015 at 08:48:55PM +0000, Robin Murphy wrote:
> Taking inspiration from the existing arch/arm code, break out some
> generic functions to interface the DMA-API to the IOMMU-API. This will
> do the bulk of the heavy lifting for IOMMU-backed dma-mapping.
> 
> Whilst the target is arm64, rather than introduce yet another private
> implementation, place this in common code as the first step towards
> consolidating the numerous versions spread around between architecture
> code and IOMMU drivers.

Is there any reason you implemented that only for AArch64? I think it
makes a lot of sense to have a common implementation of that across
architectures (AArch64, ARM and X86).
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>  include/linux/dma-iommu.h |  78 ++++++++
>  lib/Kconfig               |   8 +
>  lib/Makefile              |   1 +
>  lib/dma-iommu.c           | 455 ++++++++++++++++++++++++++++++++++++++++++++++

I'd like this to live in drivers/iommu, as most other dma-api
implementations for iommu-drivers also live there.

> +/*
> + * This little guy is filling in until iommu_map_sg lands and we can hook that
> + * up instead (which is going to be rather involved thanks to page alignment)
> + */

iommu_map_sg should be there now. You can convert this function to it.

> +static int __iommu_dma_map_sg_simple(struct device *dev, struct scatterlist *sg,
> +		int nents, enum dma_data_direction dir, struct dma_attrs *attrs,
> +		bool coherent)
> +{
> +	struct scatterlist *s;
> +	int i;
> +
> +	for_each_sg(sg, s, nents, i) {
> +		sg_dma_address(s) = __iommu_dma_map_page(dev, sg_page(s), s->offset,
> +						s->length, dir, coherent);
> +		sg_dma_len(s) = s->length;
> +	}
> +	return nents;
> +}

So long,

        Joerg

[RFC PATCH 3/5] iommu: implement common IOMMU ops for DMA mapping

[Robin Murphy]

Hi Joerg,

On 27/01/15 00:21, Joerg Roedel wrote:
> Hi Robin,
>
> thanks for the patch, I think it is good start to move forward. See my
> comments below.
>
> On Mon, Jan 12, 2015 at 08:48:55PM +0000, Robin Murphy wrote:
>> Taking inspiration from the existing arch/arm code, break out some
>> generic functions to interface the DMA-API to the IOMMU-API. This will
>> do the bulk of the heavy lifting for IOMMU-backed dma-mapping.
>>
>> Whilst the target is arm64, rather than introduce yet another private
>> implementation, place this in common code as the first step towards
>> consolidating the numerous versions spread around between architecture
>> code and IOMMU drivers.
>
> Is there any reason you implemented that only for AArch64? I think it
> makes a lot of sense to have a common implementation of that across
> architectures (AArch64, ARM and X86).

Laz^WPragmatism - I'm expecting quite a lot of changes to get this 
looking good, so keeping the series as lean as possible to aid 
reviewing/rebasing/etc. seemed sensible. In the same vein, since the 
other architectures already have code that works, my priority is getting 
something in place to fill the gap in arm64 (my current remit is "get 
the SMMUs on Juno working"); it seemed logical to minimise disruption 
and dependencies by aiming to get this merged with the one user, then 
start porting the others (and making the inevitable necessary tweaks) 
once it's in.

I'll adjust the commit message to make that clearer - on re-reading it, 
it does come across as rather vague about that intent.

>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>>   include/linux/dma-iommu.h |  78 ++++++++
>>   lib/Kconfig               |   8 +
>>   lib/Makefile              |   1 +
>>   lib/dma-iommu.c           | 455 ++++++++++++++++++++++++++++++++++++++++++++++
>
> I'd like this to live in drivers/iommu, as most other dma-api
> implementations for iommu-drivers also live there.
>

That's reasonable - I was trying to model this on SWIOTLB, so it ended 
up in the same place. Mind you, I suppose there's a fair argument for 
moving SWIOTLB over to drivers/iommu too.

>> +/*
>> + * This little guy is filling in until iommu_map_sg lands and we can hook that
>> + * up instead (which is going to be rather involved thanks to page alignment)
>> + */
>
> iommu_map_sg should be there now. You can convert this function to it.
>

Indeed, that comment is pretty ancient and the 'proper' one was already 
half-done when I posted this; It'll be in v2.

Thanks,
Robin.

>> +static int __iommu_dma_map_sg_simple(struct device *dev, struct scatterlist *sg,
>> +		int nents, enum dma_data_direction dir, struct dma_attrs *attrs,
>> +		bool coherent)
>> +{
>> +	struct scatterlist *s;
>> +	int i;
>> +
>> +	for_each_sg(sg, s, nents, i) {
>> +		sg_dma_address(s) = __iommu_dma_map_page(dev, sg_page(s), s->offset,
>> +						s->length, dir, coherent);
>> +		sg_dma_len(s) = s->length;
>> +	}
>> +	return nents;
>> +}
>
> So long,
>
>          Joerg
>
>

[RFC PATCH 3/5] iommu: implement common IOMMU ops for DMA mapping

[Joerg Roedel]

On Tue, Jan 27, 2015 at 12:27:39PM +0000, Robin Murphy wrote:
> Laz^WPragmatism - I'm expecting quite a lot of changes to get this
> looking good, so keeping the series as lean as possible to aid
> reviewing/rebasing/etc. seemed sensible. In the same vein, since the
> other architectures already have code that works, my priority is
> getting something in place to fill the gap in arm64 (my current
> remit is "get the SMMUs on Juno working"); it seemed logical to
> minimise disruption and dependencies by aiming to get this merged
> with the one user, then start porting the others (and making the
> inevitable necessary tweaks) once it's in.
> 
> I'll adjust the commit message to make that clearer - on re-reading
> it, it does come across as rather vague about that intent.

Yeah, probably we can add other architectures later (like x86). But can
you at least merge it with the existing version of this for ARM32? That
should be easier to achieve than extending it for x86 by now and we do
not end up with two similar implementations.

> >>  lib/dma-iommu.c           | 455 ++++++++++++++++++++++++++++++++++++++++++++++
> >
> >I'd like this to live in drivers/iommu, as most other dma-api
> >implementations for iommu-drivers also live there.
> >
> 
> That's reasonable - I was trying to model this on SWIOTLB, so it
> ended up in the same place. Mind you, I suppose there's a fair
> argument for moving SWIOTLB over to drivers/iommu too.

SWIOTLB is used outside of iommu code too, like in Xen for example. So I
think it could stay in lib/. But a dma-ops implemention using iommu-api
only used iommu-code and should be in drivers/iommu.

> Indeed, that comment is pretty ancient and the 'proper' one was
> already half-done when I posted this; It'll be in v2.

Thanks.

Regards,

	Joerg

[RFC PATCH 3/5] iommu: implement common IOMMU ops for DMA mapping

[Will Deacon]

On Tue, Jan 27, 2015 at 12:38:09PM +0000, Joerg Roedel wrote:
> On Tue, Jan 27, 2015 at 12:27:39PM +0000, Robin Murphy wrote:
> > Laz^WPragmatism - I'm expecting quite a lot of changes to get this
> > looking good, so keeping the series as lean as possible to aid
> > reviewing/rebasing/etc. seemed sensible. In the same vein, since the
> > other architectures already have code that works, my priority is
> > getting something in place to fill the gap in arm64 (my current
> > remit is "get the SMMUs on Juno working"); it seemed logical to
> > minimise disruption and dependencies by aiming to get this merged
> > with the one user, then start porting the others (and making the
> > inevitable necessary tweaks) once it's in.
> > 
> > I'll adjust the commit message to make that clearer - on re-reading
> > it, it does come across as rather vague about that intent.
> 
> Yeah, probably we can add other architectures later (like x86). But can
> you at least merge it with the existing version of this for ARM32? That
> should be easier to achieve than extending it for x86 by now and we do
> not end up with two similar implementations.

+1 on that front. We've already had some breakage by using the arm_iommu_*
API for the automatic DMA mapping bits, so I'd love to have dma-mapping
use the same core code between arm and arm64 as soon as we can, leaving
the ARM-specific API for the (hopefully diminishing) set of explicit
callers.

Will

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Robin Murphy]

Taking some inspiration from the arch/arm code, implement the
arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 arch/arm64/include/asm/device.h      |   3 +
 arch/arm64/include/asm/dma-mapping.h |  12 ++
 arch/arm64/mm/dma-mapping.c          | 297 +++++++++++++++++++++++++++++++++++
 3 files changed, 312 insertions(+)

diff --git a/arch/arm64/include/asm/device.h b/arch/arm64/include/asm/device.h
index 243ef25..c17f100 100644
--- a/arch/arm64/include/asm/device.h
+++ b/arch/arm64/include/asm/device.h
@@ -20,6 +20,9 @@ struct dev_archdata {
 	struct dma_map_ops *dma_ops;
 #ifdef CONFIG_IOMMU_API
 	void *iommu;			/* private IOMMU data */
+#ifdef CONFIG_IOMMU_DMA
+	struct iommu_dma_mapping *mapping;
+#endif
 #endif
 	bool dma_coherent;
 };
diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
index 6932bb5..82082c4 100644
--- a/arch/arm64/include/asm/dma-mapping.h
+++ b/arch/arm64/include/asm/dma-mapping.h
@@ -64,11 +64,23 @@ static inline bool is_device_dma_coherent(struct device *dev)
 
 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
+#ifdef CONFIG_IOMMU_DMA
+	/* We don't have an easy way of dealing with this... */
+	BUG_ON(dev->archdata.mapping);
+#endif
 	return (dma_addr_t)paddr;
 }
 
+#ifdef CONFIG_IOMMU_DMA
+phys_addr_t iova_to_phys(struct device *dev, dma_addr_t dev_addr);
+#endif
+
 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
 {
+#ifdef CONFIG_IOMMU_DMA
+	if (dev->archdata.mapping)
+		return iova_to_phys(dev, dev_addr);
+#endif
 	return (phys_addr_t)dev_addr;
 }
 
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 0a24b9b..8e449a7 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -23,6 +23,7 @@
 #include <linux/genalloc.h>
 #include <linux/dma-mapping.h>
 #include <linux/dma-contiguous.h>
+#include <linux/dma-iommu.h>
 #include <linux/vmalloc.h>
 #include <linux/swiotlb.h>
 
@@ -426,6 +427,9 @@ static int __init arm64_dma_init(void)
 
 	ret |= swiotlb_late_init();
 	ret |= atomic_pool_init();
+#ifdef CONFIG_IOMMU_DMA
+	ret |= iommu_dma_init();
+#endif
 
 	return ret;
 }
@@ -439,3 +443,296 @@ static int __init dma_debug_do_init(void)
 	return 0;
 }
 fs_initcall(dma_debug_do_init);
+
+
+#ifdef CONFIG_IOMMU_DMA
+
+static struct page **__atomic_get_pages(void *addr)
+{
+	struct page *page;
+	phys_addr_t phys;
+
+	phys = gen_pool_virt_to_phys(atomic_pool, (unsigned long)addr);
+	page = phys_to_page(phys);
+
+	return (struct page **)page;
+}
+
+static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
+{
+	struct vm_struct *area;
+
+	if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
+		return __atomic_get_pages(cpu_addr);
+
+	area = find_vm_area(cpu_addr);
+	if (!area)
+		return NULL;
+
+	return area->pages;
+}
+
+static void *__iommu_alloc_atomic(struct device *dev, size_t size,
+				  dma_addr_t *handle, bool coherent)
+{
+	struct page *page;
+	void *addr;
+
+	addr = __alloc_from_pool(size, &page);
+	if (!addr)
+		return NULL;
+
+	*handle = iommu_dma_create_iova_mapping(dev, &page, size, coherent);
+	if (*handle == DMA_ERROR_CODE) {
+		__free_from_pool(addr, size);
+		return NULL;
+	}
+	return addr;
+}
+
+static void __iommu_free_atomic(struct device *dev, void *cpu_addr,
+				dma_addr_t handle, size_t size)
+{
+	iommu_dma_release_iova_mapping(dev, handle, size);
+	__free_from_pool(cpu_addr, size);
+}
+
+static void __dma_clear_buffer(struct page *page, size_t size)
+{
+	void *ptr = page_address(page);
+
+	memset(ptr, 0, size);
+	__dma_flush_range(ptr, ptr + size);
+}
+
+static void *__iommu_alloc_attrs(struct device *dev, size_t size,
+	    dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
+{
+	bool coherent = is_device_dma_coherent(dev);
+	pgprot_t prot = coherent ? __pgprot(PROT_NORMAL) :
+				   __pgprot(PROT_NORMAL_NC);
+	struct page **pages;
+	void *addr = NULL;
+
+	*handle = DMA_ERROR_CODE;
+	size = PAGE_ALIGN(size);
+
+	if (!(gfp & __GFP_WAIT))
+		return __iommu_alloc_atomic(dev, size, handle, coherent);
+	/*
+	 * Following is a work-around (a.k.a. hack) to prevent pages
+	 * with __GFP_COMP being passed to split_page() which cannot
+	 * handle them.  The real problem is that this flag probably
+	 * should be 0 on ARM as it is not supported on this
+	 * platform; see CONFIG_HUGETLBFS.
+	 */
+	gfp &= ~(__GFP_COMP);
+
+	pages = iommu_dma_alloc_buffer(dev, size, gfp, attrs,
+			__dma_clear_buffer);
+	if (!pages)
+		return NULL;
+
+	*handle = iommu_dma_create_iova_mapping(dev, pages, size, coherent);
+	if (*handle == DMA_ERROR_CODE)
+		goto err_mapping;
+
+	addr = dma_common_pages_remap(pages, size, VM_USERMAP,
+				      __get_dma_pgprot(attrs, prot, coherent),
+				      __builtin_return_address(0));
+	if (addr)
+		return addr;
+
+	iommu_dma_release_iova_mapping(dev, *handle, size);
+err_mapping:
+	iommu_dma_free_buffer(dev, pages, size, attrs);
+	return NULL;
+}
+
+static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
+			       dma_addr_t handle, struct dma_attrs *attrs)
+{
+	struct page **pages;
+
+	size = PAGE_ALIGN(size);
+	if (__in_atomic_pool(cpu_addr, size)) {
+		__iommu_free_atomic(dev, cpu_addr, handle, size);
+		return;
+	}
+
+	pages = __iommu_get_pages(cpu_addr, attrs);
+	if (!pages) {
+		WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
+		return;
+	}
+
+	dma_common_free_remap(cpu_addr, size, VM_USERMAP);
+
+	iommu_dma_release_iova_mapping(dev, handle, size);
+	iommu_dma_free_buffer(dev, pages, size, attrs);
+}
+
+static inline void *iova_to_virt(struct device *dev, dma_addr_t dev_addr)
+{
+	if (dev_addr == DMA_ERROR_CODE)
+		return NULL;
+	return phys_to_virt(iova_to_phys(dev, dev_addr));
+}
+
+static void __iommu_sync_single_for_cpu(struct device *dev,
+					dma_addr_t dev_addr, size_t size,
+					enum dma_data_direction dir)
+{
+	if (!is_device_dma_coherent(dev))
+		__dma_unmap_area(iova_to_virt(dev, dev_addr), size, dir);
+}
+
+static void __iommu_sync_single_for_device(struct device *dev,
+					   dma_addr_t dev_addr, size_t size,
+					   enum dma_data_direction dir)
+{
+	if (!is_device_dma_coherent(dev))
+		__dma_map_area(iova_to_virt(dev, dev_addr), size, dir);
+}
+
+static dma_addr_t __iommu_map_page(struct device *dev, struct page *page,
+				   unsigned long offset, size_t size,
+				   enum dma_data_direction dir,
+				   struct dma_attrs *attrs)
+{
+	dma_addr_t dev_addr;
+
+	if (is_device_dma_coherent(dev))
+		return iommu_dma_coherent_map_page(dev, page, offset, size,
+				dir, attrs);
+
+	dev_addr = iommu_dma_map_page(dev, page, offset, size, dir, attrs);
+	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+		__iommu_sync_single_for_device(dev, dev_addr, size, dir);
+
+	return dev_addr;
+}
+
+static void __iommu_unmap_page(struct device *dev, dma_addr_t dev_addr,
+			       size_t size, enum dma_data_direction dir,
+			       struct dma_attrs *attrs)
+{
+	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+		__iommu_sync_single_for_cpu(dev, dev_addr, size, dir);
+
+	iommu_dma_unmap_page(dev, dev_addr, size, dir, attrs);
+}
+
+static void __iommu_sync_sg_for_cpu(struct device *dev,
+				    struct scatterlist *sgl, int nelems,
+				    enum dma_data_direction dir)
+{
+	struct scatterlist *sg;
+	int i;
+
+	if (is_device_dma_coherent(dev))
+		return;
+
+	for_each_sg(sgl, sg, nelems, i) {
+		unsigned int len = sg_dma_len(sg);
+		void *virt = iova_to_virt(dev, sg_dma_address(sg));
+
+		if (virt && len)
+			__dma_unmap_area(virt, len, dir);
+	}
+}
+
+static void __iommu_sync_sg_for_device(struct device *dev,
+				       struct scatterlist *sgl, int nelems,
+				       enum dma_data_direction dir)
+{
+	struct scatterlist *sg;
+	int i;
+
+	if (is_device_dma_coherent(dev))
+		return;
+
+	for_each_sg(sgl, sg, nelems, i) {
+		unsigned int len = sg_dma_len(sg);
+		void *virt = iova_to_virt(dev, sg_dma_address(sg));
+
+		if (virt && len)
+			__dma_map_area(virt, len, dir);
+	}
+}
+
+static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
+				int nelems, enum dma_data_direction dir,
+				struct dma_attrs *attrs)
+{
+	int count;
+
+	if (is_device_dma_coherent(dev))
+		return iommu_dma_coherent_map_sg(dev, sgl, nelems, dir, attrs);
+
+	count = iommu_dma_map_sg(dev, sgl, nelems, dir, attrs);
+	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+		__iommu_sync_sg_for_device(dev, sgl, count, dir);
+
+	return count;
+}
+
+static void __iommu_unmap_sg_attrs(struct device *dev,
+				   struct scatterlist *sgl, int nelems,
+				   enum dma_data_direction dir,
+				   struct dma_attrs *attrs)
+{
+	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+		__iommu_sync_sg_for_cpu(dev, sgl, nelems, dir);
+
+	iommu_dma_unmap_sg(dev, sgl, nelems, dir, attrs);
+}
+
+static struct dma_map_ops iommu_dma_ops = {
+	.alloc = __iommu_alloc_attrs,
+	.free = __iommu_free_attrs,
+	.mmap = __swiotlb_mmap,
+	.map_page = __iommu_map_page,
+	.unmap_page = __iommu_unmap_page,
+	.map_sg = __iommu_map_sg_attrs,
+	.unmap_sg = __iommu_unmap_sg_attrs,
+	.sync_single_for_cpu = __iommu_sync_single_for_cpu,
+	.sync_single_for_device = __iommu_sync_single_for_device,
+	.sync_sg_for_cpu = __iommu_sync_sg_for_cpu,
+	.sync_sg_for_device = __iommu_sync_sg_for_device,
+	.dma_supported = iommu_dma_supported,
+	.mapping_error = iommu_dma_mapping_error,
+};
+
+static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+				  struct iommu_ops *ops)
+{
+	struct iommu_dma_mapping *mapping;
+
+	if (!ops)
+		return;
+
+	mapping = iommu_dma_create_mapping(ops, dma_base, size);
+	if (!mapping) {
+		pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",
+				size, dev_name(dev));
+		return;
+	}
+
+	if (iommu_dma_attach_device(dev, mapping))
+		pr_warn("Failed to attach device %s to IOMMU mapping\n",
+				dev_name(dev));
+	else
+		dev->archdata.dma_ops = &iommu_dma_ops;
+
+	/* drop the initial mapping refcount */
+	iommu_dma_release_mapping(mapping);
+}
+
+#else
+
+static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+				  struct iommu_ops *iommu)
+{ }
+
+#endif  /* CONFIG_IOMMU_DMA */
-- 
1.9.1

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Will Deacon]

On Mon, Jan 12, 2015 at 08:48:56PM +0000, Robin Murphy wrote:
> Taking some inspiration from the arch/arm code, implement the
> arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>  arch/arm64/include/asm/device.h      |   3 +
>  arch/arm64/include/asm/dma-mapping.h |  12 ++
>  arch/arm64/mm/dma-mapping.c          | 297 +++++++++++++++++++++++++++++++++++
>  3 files changed, 312 insertions(+)
> 
> diff --git a/arch/arm64/include/asm/device.h b/arch/arm64/include/asm/device.h
> index 243ef25..c17f100 100644
> --- a/arch/arm64/include/asm/device.h
> +++ b/arch/arm64/include/asm/device.h
> @@ -20,6 +20,9 @@ struct dev_archdata {
>  	struct dma_map_ops *dma_ops;
>  #ifdef CONFIG_IOMMU_API
>  	void *iommu;			/* private IOMMU data */
> +#ifdef CONFIG_IOMMU_DMA
> +	struct iommu_dma_mapping *mapping;
> +#endif
>  #endif
>  	bool dma_coherent;
>  };
> diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
> index 6932bb5..82082c4 100644
> --- a/arch/arm64/include/asm/dma-mapping.h
> +++ b/arch/arm64/include/asm/dma-mapping.h
> @@ -64,11 +64,23 @@ static inline bool is_device_dma_coherent(struct device *dev)
>  
>  static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
>  {
> +#ifdef CONFIG_IOMMU_DMA
> +	/* We don't have an easy way of dealing with this... */
> +	BUG_ON(dev->archdata.mapping);
> +#endif
>  	return (dma_addr_t)paddr;
>  }
>  
> +#ifdef CONFIG_IOMMU_DMA
> +phys_addr_t iova_to_phys(struct device *dev, dma_addr_t dev_addr);

I think this name is a bit too generic, especially as we already have an
iommu_iova_to_phys function in drivers/iommu/iommu.c

In fact, can't you just make CONFIG_IOMMU_DMA depend on IOMMU_API and then
use iommu_iova_to_phys instead?

> +#endif
> +
>  static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
>  {
> +#ifdef CONFIG_IOMMU_DMA
> +	if (dev->archdata.mapping)
> +		return iova_to_phys(dev, dev_addr);
> +#endif
>  	return (phys_addr_t)dev_addr;
>  }

It would be cleaner just to define these functions twice; with and without
the CONFIG_IOMMU_DMA case.

> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
> index 0a24b9b..8e449a7 100644
> --- a/arch/arm64/mm/dma-mapping.c
> +++ b/arch/arm64/mm/dma-mapping.c
> @@ -23,6 +23,7 @@
>  #include <linux/genalloc.h>
>  #include <linux/dma-mapping.h>
>  #include <linux/dma-contiguous.h>
> +#include <linux/dma-iommu.h>
>  #include <linux/vmalloc.h>
>  #include <linux/swiotlb.h>
>  
> @@ -426,6 +427,9 @@ static int __init arm64_dma_init(void)
>  
>  	ret |= swiotlb_late_init();
>  	ret |= atomic_pool_init();
> +#ifdef CONFIG_IOMMU_DMA
> +	ret |= iommu_dma_init();
> +#endif

Same here, just make an empty iommu_dma_init if !CONFIG_IOMMU_DMA.

>  	return ret;
>  }
> @@ -439,3 +443,296 @@ static int __init dma_debug_do_init(void)
>  	return 0;
>  }
>  fs_initcall(dma_debug_do_init);
> +
> +
> +#ifdef CONFIG_IOMMU_DMA
> +
> +static struct page **__atomic_get_pages(void *addr)
> +{
> +	struct page *page;
> +	phys_addr_t phys;
> +
> +	phys = gen_pool_virt_to_phys(atomic_pool, (unsigned long)addr);
> +	page = phys_to_page(phys);
> +
> +	return (struct page **)page;
> +}
> +
> +static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
> +{
> +	struct vm_struct *area;
> +
> +	if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
> +		return __atomic_get_pages(cpu_addr);
> +
> +	area = find_vm_area(cpu_addr);
> +	if (!area)
> +		return NULL;
> +
> +	return area->pages;
> +}
> +
> +static void *__iommu_alloc_atomic(struct device *dev, size_t size,
> +				  dma_addr_t *handle, bool coherent)
> +{
> +	struct page *page;
> +	void *addr;
> +
> +	addr = __alloc_from_pool(size, &page);
> +	if (!addr)
> +		return NULL;
> +
> +	*handle = iommu_dma_create_iova_mapping(dev, &page, size, coherent);
> +	if (*handle == DMA_ERROR_CODE) {
> +		__free_from_pool(addr, size);
> +		return NULL;
> +	}
> +	return addr;
> +}
> +
> +static void __iommu_free_atomic(struct device *dev, void *cpu_addr,
> +				dma_addr_t handle, size_t size)
> +{
> +	iommu_dma_release_iova_mapping(dev, handle, size);
> +	__free_from_pool(cpu_addr, size);
> +}
> +
> +static void __dma_clear_buffer(struct page *page, size_t size)
> +{
> +	void *ptr = page_address(page);
> +
> +	memset(ptr, 0, size);
> +	__dma_flush_range(ptr, ptr + size);
> +}
> +
> +static void *__iommu_alloc_attrs(struct device *dev, size_t size,
> +	    dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
> +{
> +	bool coherent = is_device_dma_coherent(dev);
> +	pgprot_t prot = coherent ? __pgprot(PROT_NORMAL) :
> +				   __pgprot(PROT_NORMAL_NC);
> +	struct page **pages;
> +	void *addr = NULL;
> +
> +	*handle = DMA_ERROR_CODE;
> +	size = PAGE_ALIGN(size);
> +
> +	if (!(gfp & __GFP_WAIT))
> +		return __iommu_alloc_atomic(dev, size, handle, coherent);
> +	/*
> +	 * Following is a work-around (a.k.a. hack) to prevent pages
> +	 * with __GFP_COMP being passed to split_page() which cannot
> +	 * handle them.  The real problem is that this flag probably
> +	 * should be 0 on ARM as it is not supported on this
> +	 * platform; see CONFIG_HUGETLBFS.
> +	 */
> +	gfp &= ~(__GFP_COMP);

This comment seems to have been copied from avr32 to arm to arm64 and has
the assumption that the architecture in question doesn't support hugepages.
That's not a valid assumption on LPAE ARM or arm64, so I'd like to get to
the bottom of this.

Will

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Robin Murphy]

Hi Will,

Thanks for taking a look

On 23/01/15 15:26, Will Deacon wrote:
> On Mon, Jan 12, 2015 at 08:48:56PM +0000, Robin Murphy wrote:
>> Taking some inspiration from the arch/arm code, implement the
>> arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>>   arch/arm64/include/asm/device.h      |   3 +
>>   arch/arm64/include/asm/dma-mapping.h |  12 ++
>>   arch/arm64/mm/dma-mapping.c          | 297 +++++++++++++++++++++++++++++++++++
>>   3 files changed, 312 insertions(+)
>>
>> diff --git a/arch/arm64/include/asm/device.h b/arch/arm64/include/asm/device.h
>> index 243ef25..c17f100 100644
>> --- a/arch/arm64/include/asm/device.h
>> +++ b/arch/arm64/include/asm/device.h
>> @@ -20,6 +20,9 @@ struct dev_archdata {
>>   	struct dma_map_ops *dma_ops;
>>   #ifdef CONFIG_IOMMU_API
>>   	void *iommu;			/* private IOMMU data */
>> +#ifdef CONFIG_IOMMU_DMA
>> +	struct iommu_dma_mapping *mapping;
>> +#endif
>>   #endif
>>   	bool dma_coherent;
>>   };
>> diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
>> index 6932bb5..82082c4 100644
>> --- a/arch/arm64/include/asm/dma-mapping.h
>> +++ b/arch/arm64/include/asm/dma-mapping.h
>> @@ -64,11 +64,23 @@ static inline bool is_device_dma_coherent(struct device *dev)
>>
>>   static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
>>   {
>> +#ifdef CONFIG_IOMMU_DMA
>> +	/* We don't have an easy way of dealing with this... */
>> +	BUG_ON(dev->archdata.mapping);
>> +#endif
>>   	return (dma_addr_t)paddr;
>>   }
>>
>> +#ifdef CONFIG_IOMMU_DMA
>> +phys_addr_t iova_to_phys(struct device *dev, dma_addr_t dev_addr);
>
> I think this name is a bit too generic, especially as we already have an
> iommu_iova_to_phys function in drivers/iommu/iommu.c
>
> In fact, can't you just make CONFIG_IOMMU_DMA depend on IOMMU_API and then
> use iommu_iova_to_phys instead?
>

Yeah, I've already added the dependency on IOMMU_API (which should have 
been there anyway) and jiggled things about so the iommu_domain can be 
got at, so that's reasonable.

>> +#endif
>> +
>>   static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
>>   {
>> +#ifdef CONFIG_IOMMU_DMA
>> +	if (dev->archdata.mapping)
>> +		return iova_to_phys(dev, dev_addr);
>> +#endif
>>   	return (phys_addr_t)dev_addr;
>>   }
>
> It would be cleaner just to define these functions twice; with and without
> the CONFIG_IOMMU_DMA case.
>

If that's the preferred style, sure.

>> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
>> index 0a24b9b..8e449a7 100644
>> --- a/arch/arm64/mm/dma-mapping.c
>> +++ b/arch/arm64/mm/dma-mapping.c
>> @@ -23,6 +23,7 @@
>>   #include <linux/genalloc.h>
>>   #include <linux/dma-mapping.h>
>>   #include <linux/dma-contiguous.h>
>> +#include <linux/dma-iommu.h>
>>   #include <linux/vmalloc.h>
>>   #include <linux/swiotlb.h>
>>
>> @@ -426,6 +427,9 @@ static int __init arm64_dma_init(void)
>>
>>   	ret |= swiotlb_late_init();
>>   	ret |= atomic_pool_init();
>> +#ifdef CONFIG_IOMMU_DMA
>> +	ret |= iommu_dma_init();
>> +#endif
>
> Same here, just make an empty iommu_dma_init if !CONFIG_IOMMU_DMA.
>

*checks dev branch* Heh, I did that much already but haven't updated 
this bit, thanks for the poke. Incidentally, I just followed the pattern 
here but is the bitwise munging of return values actually sound? It 
strikes me that failing fast with a specific error is better than trying 
everything and returning nonsense in the face of multiple failures, but 
then I don't know the vagaries of initcalls.

>>   	return ret;
>>   }
>> @@ -439,3 +443,296 @@ static int __init dma_debug_do_init(void)
>>   	return 0;
>>   }
>>   fs_initcall(dma_debug_do_init);
>> +
>> +
>> +#ifdef CONFIG_IOMMU_DMA
>> +
>> +static struct page **__atomic_get_pages(void *addr)
>> +{
>> +	struct page *page;
>> +	phys_addr_t phys;
>> +
>> +	phys = gen_pool_virt_to_phys(atomic_pool, (unsigned long)addr);
>> +	page = phys_to_page(phys);
>> +
>> +	return (struct page **)page;
>> +}
>> +
>> +static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
>> +{
>> +	struct vm_struct *area;
>> +
>> +	if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
>> +		return __atomic_get_pages(cpu_addr);
>> +
>> +	area = find_vm_area(cpu_addr);
>> +	if (!area)
>> +		return NULL;
>> +
>> +	return area->pages;
>> +}
>> +
>> +static void *__iommu_alloc_atomic(struct device *dev, size_t size,
>> +				  dma_addr_t *handle, bool coherent)
>> +{
>> +	struct page *page;
>> +	void *addr;
>> +
>> +	addr = __alloc_from_pool(size, &page);
>> +	if (!addr)
>> +		return NULL;
>> +
>> +	*handle = iommu_dma_create_iova_mapping(dev, &page, size, coherent);
>> +	if (*handle == DMA_ERROR_CODE) {
>> +		__free_from_pool(addr, size);
>> +		return NULL;
>> +	}
>> +	return addr;
>> +}
>> +
>> +static void __iommu_free_atomic(struct device *dev, void *cpu_addr,
>> +				dma_addr_t handle, size_t size)
>> +{
>> +	iommu_dma_release_iova_mapping(dev, handle, size);
>> +	__free_from_pool(cpu_addr, size);
>> +}
>> +
>> +static void __dma_clear_buffer(struct page *page, size_t size)
>> +{
>> +	void *ptr = page_address(page);
>> +
>> +	memset(ptr, 0, size);
>> +	__dma_flush_range(ptr, ptr + size);
>> +}
>> +
>> +static void *__iommu_alloc_attrs(struct device *dev, size_t size,
>> +	    dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
>> +{
>> +	bool coherent = is_device_dma_coherent(dev);
>> +	pgprot_t prot = coherent ? __pgprot(PROT_NORMAL) :
>> +				   __pgprot(PROT_NORMAL_NC);
>> +	struct page **pages;
>> +	void *addr = NULL;
>> +
>> +	*handle = DMA_ERROR_CODE;
>> +	size = PAGE_ALIGN(size);
>> +
>> +	if (!(gfp & __GFP_WAIT))
>> +		return __iommu_alloc_atomic(dev, size, handle, coherent);
>> +	/*
>> +	 * Following is a work-around (a.k.a. hack) to prevent pages
>> +	 * with __GFP_COMP being passed to split_page() which cannot
>> +	 * handle them.  The real problem is that this flag probably
>> +	 * should be 0 on ARM as it is not supported on this
>> +	 * platform; see CONFIG_HUGETLBFS.
>> +	 */
>> +	gfp &= ~(__GFP_COMP);
>
> This comment seems to have been copied from avr32 to arm to arm64 and has
> the assumption that the architecture in question doesn't support hugepages.
> That's not a valid assumption on LPAE ARM or arm64, so I'd like to get to
> the bottom of this.

Yup, it stinks like a dead cat in a pallet of PC cases (true story), but 
falls squarely in the "things I don't really understand but apparently 
work so copied verbatim" camp (along with the arm __iommu_alloc_buffer 
implementation). Indeed, I was rather hoping someone might flag it up 
for the attention of people who know what to do.


Robin.

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Joseph Lo]

On 01/13/2015 04:48 AM, Robin Murphy wrote:
> Taking some inspiration from the arch/arm code, implement the
> arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   arch/arm64/include/asm/device.h      |   3 +
>   arch/arm64/include/asm/dma-mapping.h |  12 ++
>   arch/arm64/mm/dma-mapping.c          | 297 +++++++++++++++++++++++++++++++++++
>   3 files changed, 312 insertions(+)
>
[snip]
> +static struct dma_map_ops iommu_dma_ops = {
> +	.alloc = __iommu_alloc_attrs,
> +	.free = __iommu_free_attrs,
> +	.mmap = __swiotlb_mmap,

Hi Robin,

Thanks for posting this series. I spent some time to re-write Tegra-smmu 
driver to work with the new DT-based iommu initialization procedure and 
do some modification in Tegra/DRM driver to make it work with 
IOMMU-backed DMA mapping API.

Found two issues, one is the mmap function here.
The mmap function is not reliable, the userspace application and kernel 
easily leads to crash after calling this. Can we mmap the CPU VA to the 
IOVA?
This issue was gone after replacing it with the same function 
(arm_iommu_mmap_attrs) in the ARM32 kernel. And everything just works fine.

> +	.map_page = __iommu_map_page,
> +	.unmap_page = __iommu_unmap_page,
> +	.map_sg = __iommu_map_sg_attrs,
> +	.unmap_sg = __iommu_unmap_sg_attrs,
> +	.sync_single_for_cpu = __iommu_sync_single_for_cpu,
> +	.sync_single_for_device = __iommu_sync_single_for_device,
> +	.sync_sg_for_cpu = __iommu_sync_sg_for_cpu,
> +	.sync_sg_for_device = __iommu_sync_sg_for_device,
> +	.dma_supported = iommu_dma_supported,
> +	.mapping_error = iommu_dma_mapping_error,
> +};
> +
> +static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> +				  struct iommu_ops *ops)
> +{
> +	struct iommu_dma_mapping *mapping;
> +
> +	if (!ops)
> +		return;
> +
> +	mapping = iommu_dma_create_mapping(ops, dma_base, size);

The other issue is here. We create a DMA range here, but the 
__iova_alloc not really working with that, if the end of the range was 
under 4G limitation. The allocation address always starts from 
0xfffxxxxx, because we set the .dma_mask to DMA_BIT_MASK(32) by default. 
If we don't expect that, we need one more function call like 
dma_coerce_mask_and_coherent(dev, 0x80000000) for the range of 0 to 2G 
for example.

Does this the expectation when we use this framework?

(Except the issue of __alloc_iova, I am ok with this. We could set up a 
default range from 0 to 4G for every device by default, and then isolate 
the virtual range by reset the .dma_mask of the device later.)

Thanks,
-Joseph

> +	if (!mapping) {
> +		pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",
> +				size, dev_name(dev));
> +		return;
> +	}
> +
> +	if (iommu_dma_attach_device(dev, mapping))
> +		pr_warn("Failed to attach device %s to IOMMU mapping\n",
> +				dev_name(dev));
> +	else
> +		dev->archdata.dma_ops = &iommu_dma_ops;
> +
> +	/* drop the initial mapping refcount */
> +	iommu_dma_release_mapping(mapping);
> +}
> +
> +#else
> +
> +static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> +				  struct iommu_ops *iommu)
> +{ }
> +
> +#endif  /* CONFIG_IOMMU_DMA */
>

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Robin Murphy]

Hi Joseph,

Thanks for giving it a spin,

On 26/01/15 03:25, Joseph Lo wrote:
> On 01/13/2015 04:48 AM, Robin Murphy wrote:
>> Taking some inspiration from the arch/arm code, implement the
>> arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>>    arch/arm64/include/asm/device.h      |   3 +
>>    arch/arm64/include/asm/dma-mapping.h |  12 ++
>>    arch/arm64/mm/dma-mapping.c          | 297 +++++++++++++++++++++++++++++++++++
>>    3 files changed, 312 insertions(+)
>>
> [snip]
>> +static struct dma_map_ops iommu_dma_ops = {
>> +	.alloc = __iommu_alloc_attrs,
>> +	.free = __iommu_free_attrs,
>> +	.mmap = __swiotlb_mmap,
>
> Hi Robin,
>
> Thanks for posting this series. I spent some time to re-write Tegra-smmu
> driver to work with the new DT-based iommu initialization procedure and
> do some modification in Tegra/DRM driver to make it work with
> IOMMU-backed DMA mapping API.
>
> Found two issues, one is the mmap function here.
> The mmap function is not reliable, the userspace application and kernel
> easily leads to crash after calling this. Can we mmap the CPU VA to the
> IOVA?
> This issue was gone after replacing it with the same function
> (arm_iommu_mmap_attrs) in the ARM32 kernel. And everything just works fine.
>

Hmm, it looks like __dma_common_mmap might rely on pages being 
contiguous, which would be a big problem I hadn't noticed. I'll have a 
dig into it and see if it's feasible to extend the existing 
implementation, otherwise we'll have to just pull in the arm_iommu 
version and have two.

>> +	.map_page = __iommu_map_page,
>> +	.unmap_page = __iommu_unmap_page,
>> +	.map_sg = __iommu_map_sg_attrs,
>> +	.unmap_sg = __iommu_unmap_sg_attrs,
>> +	.sync_single_for_cpu = __iommu_sync_single_for_cpu,
>> +	.sync_single_for_device = __iommu_sync_single_for_device,
>> +	.sync_sg_for_cpu = __iommu_sync_sg_for_cpu,
>> +	.sync_sg_for_device = __iommu_sync_sg_for_device,
>> +	.dma_supported = iommu_dma_supported,
>> +	.mapping_error = iommu_dma_mapping_error,
>> +};
>> +
>> +static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
>> +				  struct iommu_ops *ops)
>> +{
>> +	struct iommu_dma_mapping *mapping;
>> +
>> +	if (!ops)
>> +		return;
>> +
>> +	mapping = iommu_dma_create_mapping(ops, dma_base, size);
>
> The other issue is here. We create a DMA range here, but the
> __iova_alloc not really working with that, if the end of the range was
> under 4G limitation. The allocation address always starts from
> 0xfffxxxxx, because we set the .dma_mask to DMA_BIT_MASK(32) by default.
> If we don't expect that, we need one more function call like
> dma_coerce_mask_and_coherent(dev, 0x80000000) for the range of 0 to 2G
> for example.
>
> Does this the expectation when we use this framework?
>
> (Except the issue of __alloc_iova, I am ok with this. We could set up a
> default range from 0 to 4G for every device by default, and then isolate
> the virtual range by reset the .dma_mask of the device later.)
>

Yes, I failed to consider dma-ranges in this initial version, so it 
allocates based on the DMA mask alone. I hacked up an unsatisfactory 
workaround in preparation for v2, but it turns out the fix as per your 
suggestion is already in progress elsewhere[1], so I'll rework based on 
that idea.

Robin.

[1]:https://lkml.org/lkml/2015/1/23/694

> Thanks,
> -Joseph
>
>> +	if (!mapping) {
>> +		pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",
>> +				size, dev_name(dev));
>> +		return;
>> +	}
>> +
>> +	if (iommu_dma_attach_device(dev, mapping))
>> +		pr_warn("Failed to attach device %s to IOMMU mapping\n",
>> +				dev_name(dev));
>> +	else
>> +		dev->archdata.dma_ops = &iommu_dma_ops;
>> +
>> +	/* drop the initial mapping refcount */
>> +	iommu_dma_release_mapping(mapping);
>> +}
>> +
>> +#else
>> +
>> +static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
>> +				  struct iommu_ops *iommu)
>> +{ }
>> +
>> +#endif  /* CONFIG_IOMMU_DMA */
>>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Joseph Lo]

On 01/13/2015 04:48 AM, Robin Murphy wrote:
> Taking some inspiration from the arch/arm code, implement the
> arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
[snip]
>   static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
>   {
> +#ifdef CONFIG_IOMMU_DMA
> +	if (dev->archdata.mapping)

Hi Robin,

Report one more issue, it would be safer like this.
if (dev && dev->archdata.mapping)

I do some more tests with a generic buffer allocator (ION). Allocate 
buffer from ION and then import by Tegra/DRM. I saw a crash in ION.

Please reference and follow the call stack below. You could find out it 
could pass NULL of the dev pointer (ion_page_pool_alloc_pages).

[   83.836688] Call trace:
[   83.836694] [<ffffffc000422fd0>] swiotlb_sync_single+0xc/0xa4
[   83.836707] [<ffffffc0004230dc>] swiotlb_sync_sg_for_device+0x44/0x70
[   83.836713] [<ffffffc000211030>] __swiotlb_sync_sg_for_device+0x28/0xac
[   83.836720] [<ffffffc0005eb934>] ion_pages_sync_for_device+0xfc/0x10c
[   83.836724] [<ffffffc0005ecb6c>] ion_page_pool_alloc+0xc8/0xe0
[   83.836729] [<ffffffc0005ed3d0>] ion_system_heap_allocate+0xfc/0x324
[   83.836732] [<ffffffc0005eae98>] ion_alloc+0xf0/0x480
[   83.836736] [<ffffffc0005eb3bc>] ion_ioctl+0x194/0x608
[   83.836741] [<ffffffc0005eeae0>] compat_ion_ioctl+0x300/0x6e0
[   83.836747] [<ffffffc000340280>] compat_sys_ioctl+0x108/0x139c

Thanks
-Joseph

> +		return iova_to_phys(dev, dev_addr);
> +#endif
>   	return (phys_addr_t)dev_addr;
>   }

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Joseph Lo]

Hi Robin

Sorry for separate the comments into many replies.

On 01/13/2015 04:48 AM, Robin Murphy wrote:
> Taking some inspiration from the arch/arm code, implement the
> arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   arch/arm64/include/asm/device.h      |   3 +
>   arch/arm64/include/asm/dma-mapping.h |  12 ++
>   arch/arm64/mm/dma-mapping.c          | 297 +++++++++++++++++++++++++++++++++++
>   3 files changed, 312 insertions(+)
>
[snip]
> +static void __iommu_sync_sg_for_cpu(struct device *dev,
> +				    struct scatterlist *sgl, int nelems,
> +				    enum dma_data_direction dir)
> +{
> +	struct scatterlist *sg;
> +	int i;
> +
> +	if (is_device_dma_coherent(dev))
> +		return;
> +
> +	for_each_sg(sgl, sg, nelems, i) {
> +		unsigned int len = sg_dma_len(sg);
> +		void *virt = iova_to_virt(dev, sg_dma_address(sg));
> +
> +		if (virt && len)
> +			__dma_unmap_area(virt, len, dir);
> +	}
> +}
> +
> +static void __iommu_sync_sg_for_device(struct device *dev,
> +				       struct scatterlist *sgl, int nelems,
> +				       enum dma_data_direction dir)
> +{
> +	struct scatterlist *sg;
> +	int i;
> +
> +	if (is_device_dma_coherent(dev))
> +		return;
> +
> +	for_each_sg(sgl, sg, nelems, i) {
> +		unsigned int len = sg_dma_len(sg);
> +		void *virt = iova_to_virt(dev, sg_dma_address(sg));

I think we don't need to manually table walk of the IOMMU page table to 
get the PA of the iova and translate it back to CPU VA here. The page in 
the SG list already has the info we want. And same as above function. It 
just the same as the change below.

@@ -635,7 +635,7 @@ static void __iommu_sync_sg_for_cpu(struct device *dev,

         for_each_sg(sgl, sg, nelems, i) {
                 unsigned int len = sg_dma_len(sg);
-               void *virt = iova_to_virt(dev, sg_dma_address(sg));
+               void *virt = page_address(sg_page(sg));

                 if (virt && len)
                         __dma_unmap_area(virt, len, dir);
@@ -654,7 +654,7 @@ static void __iommu_sync_sg_for_device(struct device 
*dev,

         for_each_sg(sgl, sg, nelems, i) {
                 unsigned int len = sg_dma_len(sg);
-               void *virt = iova_to_virt(dev, sg_dma_address(sg));
+               void *virt = page_address(sg_page(sg));

                 if (virt && len)
                         __dma_map_area(virt, len, dir);
-Joseph

> +
> +		if (virt && len)
> +			__dma_map_area(virt, len, dir);
> +	}
> +}
> +
[snip]

[RFC PATCH 4/5] arm64: add IOMMU dma_ops

[Marek Szyprowski]

Hello,

On 2015-01-12 21:48, Robin Murphy wrote:
> Taking some inspiration from the arch/arm code, implement the
> arch-specific side of the DMA mapping ops using the new IOMMU-DMA layer.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   arch/arm64/include/asm/device.h      |   3 +
>   arch/arm64/include/asm/dma-mapping.h |  12 ++
>   arch/arm64/mm/dma-mapping.c          | 297 +++++++++++++++++++++++++++++++++++
>   3 files changed, 312 insertions(+)
>
> diff --git a/arch/arm64/include/asm/device.h b/arch/arm64/include/asm/device.h
> index 243ef25..c17f100 100644
> --- a/arch/arm64/include/asm/device.h
> +++ b/arch/arm64/include/asm/device.h
> @@ -20,6 +20,9 @@ struct dev_archdata {
>   	struct dma_map_ops *dma_ops;
>   #ifdef CONFIG_IOMMU_API
>   	void *iommu;			/* private IOMMU data */
> +#ifdef CONFIG_IOMMU_DMA
> +	struct iommu_dma_mapping *mapping;
> +#endif
>   #endif
>   	bool dma_coherent;
>   };
> diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
> index 6932bb5..82082c4 100644
> --- a/arch/arm64/include/asm/dma-mapping.h
> +++ b/arch/arm64/include/asm/dma-mapping.h
> @@ -64,11 +64,23 @@ static inline bool is_device_dma_coherent(struct device *dev)
>   
>   static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
>   {
> +#ifdef CONFIG_IOMMU_DMA
> +	/* We don't have an easy way of dealing with this... */
> +	BUG_ON(dev->archdata.mapping);
> +#endif
>   	return (dma_addr_t)paddr;
>   }
>   
> +#ifdef CONFIG_IOMMU_DMA
> +phys_addr_t iova_to_phys(struct device *dev, dma_addr_t dev_addr);
> +#endif
> +
>   static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
>   {
> +#ifdef CONFIG_IOMMU_DMA
> +	if (dev->archdata.mapping)
> +		return iova_to_phys(dev, dev_addr);
> +#endif
>   	return (phys_addr_t)dev_addr;
>   }
>   
> diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
> index 0a24b9b..8e449a7 100644
> --- a/arch/arm64/mm/dma-mapping.c
> +++ b/arch/arm64/mm/dma-mapping.c
> @@ -23,6 +23,7 @@
>   #include <linux/genalloc.h>
>   #include <linux/dma-mapping.h>
>   #include <linux/dma-contiguous.h>
> +#include <linux/dma-iommu.h>
>   #include <linux/vmalloc.h>
>   #include <linux/swiotlb.h>
>   
> @@ -426,6 +427,9 @@ static int __init arm64_dma_init(void)
>   
>   	ret |= swiotlb_late_init();
>   	ret |= atomic_pool_init();
> +#ifdef CONFIG_IOMMU_DMA
> +	ret |= iommu_dma_init();
> +#endif
>   
>   	return ret;
>   }
> @@ -439,3 +443,296 @@ static int __init dma_debug_do_init(void)
>   	return 0;
>   }
>   fs_initcall(dma_debug_do_init);
> +
> +
> +#ifdef CONFIG_IOMMU_DMA
> +
> +static struct page **__atomic_get_pages(void *addr)
> +{
> +	struct page *page;
> +	phys_addr_t phys;
> +
> +	phys = gen_pool_virt_to_phys(atomic_pool, (unsigned long)addr);
> +	page = phys_to_page(phys);
> +
> +	return (struct page **)page;
> +}
> +
> +static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
> +{
> +	struct vm_struct *area;
> +
> +	if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
> +		return __atomic_get_pages(cpu_addr);
> +
> +	area = find_vm_area(cpu_addr);
> +	if (!area)
> +		return NULL;
> +
> +	return area->pages;
> +}
> +
> +static void *__iommu_alloc_atomic(struct device *dev, size_t size,
> +				  dma_addr_t *handle, bool coherent)
> +{
> +	struct page *page;
> +	void *addr;
> +
> +	addr = __alloc_from_pool(size, &page);
> +	if (!addr)
> +		return NULL;
> +
> +	*handle = iommu_dma_create_iova_mapping(dev, &page, size, coherent);
> +	if (*handle == DMA_ERROR_CODE) {
> +		__free_from_pool(addr, size);
> +		return NULL;
> +	}
> +	return addr;
> +}
> +
> +static void __iommu_free_atomic(struct device *dev, void *cpu_addr,
> +				dma_addr_t handle, size_t size)
> +{
> +	iommu_dma_release_iova_mapping(dev, handle, size);
> +	__free_from_pool(cpu_addr, size);
> +}
> +
> +static void __dma_clear_buffer(struct page *page, size_t size)
> +{
> +	void *ptr = page_address(page);
> +
> +	memset(ptr, 0, size);
> +	__dma_flush_range(ptr, ptr + size);
> +}
> +
> +static void *__iommu_alloc_attrs(struct device *dev, size_t size,
> +	    dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
> +{
> +	bool coherent = is_device_dma_coherent(dev);
> +	pgprot_t prot = coherent ? __pgprot(PROT_NORMAL) :
> +				   __pgprot(PROT_NORMAL_NC);
> +	struct page **pages;
> +	void *addr = NULL;
> +
> +	*handle = DMA_ERROR_CODE;
> +	size = PAGE_ALIGN(size);
> +
> +	if (!(gfp & __GFP_WAIT))
> +		return __iommu_alloc_atomic(dev, size, handle, coherent);
> +	/*
> +	 * Following is a work-around (a.k.a. hack) to prevent pages
> +	 * with __GFP_COMP being passed to split_page() which cannot
> +	 * handle them.  The real problem is that this flag probably
> +	 * should be 0 on ARM as it is not supported on this
> +	 * platform; see CONFIG_HUGETLBFS.
> +	 */
> +	gfp &= ~(__GFP_COMP);
> +
> +	pages = iommu_dma_alloc_buffer(dev, size, gfp, attrs,
> +			__dma_clear_buffer);
> +	if (!pages)
> +		return NULL;
> +
> +	*handle = iommu_dma_create_iova_mapping(dev, pages, size, coherent);
> +	if (*handle == DMA_ERROR_CODE)
> +		goto err_mapping;
> +
> +	addr = dma_common_pages_remap(pages, size, VM_USERMAP,
> +				      __get_dma_pgprot(attrs, prot, coherent),
> +				      __builtin_return_address(0));
> +	if (addr)
> +		return addr;
> +
> +	iommu_dma_release_iova_mapping(dev, *handle, size);
> +err_mapping:
> +	iommu_dma_free_buffer(dev, pages, size, attrs);
> +	return NULL;
> +}
> +
> +static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
> +			       dma_addr_t handle, struct dma_attrs *attrs)
> +{
> +	struct page **pages;
> +
> +	size = PAGE_ALIGN(size);
> +	if (__in_atomic_pool(cpu_addr, size)) {
> +		__iommu_free_atomic(dev, cpu_addr, handle, size);
> +		return;
> +	}
> +
> +	pages = __iommu_get_pages(cpu_addr, attrs);
> +	if (!pages) {
> +		WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
> +		return;
> +	}
> +
> +	dma_common_free_remap(cpu_addr, size, VM_USERMAP);
> +
> +	iommu_dma_release_iova_mapping(dev, handle, size);
> +	iommu_dma_free_buffer(dev, pages, size, attrs);
> +}
> +
> +static inline void *iova_to_virt(struct device *dev, dma_addr_t dev_addr)
> +{
> +	if (dev_addr == DMA_ERROR_CODE)
> +		return NULL;
> +	return phys_to_virt(iova_to_phys(dev, dev_addr));
> +}
> +
> +static void __iommu_sync_single_for_cpu(struct device *dev,
> +					dma_addr_t dev_addr, size_t size,
> +					enum dma_data_direction dir)
> +{
> +	if (!is_device_dma_coherent(dev))
> +		__dma_unmap_area(iova_to_virt(dev, dev_addr), size, dir);
> +}
> +
> +static void __iommu_sync_single_for_device(struct device *dev,
> +					   dma_addr_t dev_addr, size_t size,
> +					   enum dma_data_direction dir)
> +{
> +	if (!is_device_dma_coherent(dev))
> +		__dma_map_area(iova_to_virt(dev, dev_addr), size, dir);
> +}
> +
> +static dma_addr_t __iommu_map_page(struct device *dev, struct page *page,
> +				   unsigned long offset, size_t size,
> +				   enum dma_data_direction dir,
> +				   struct dma_attrs *attrs)
> +{
> +	dma_addr_t dev_addr;
> +
> +	if (is_device_dma_coherent(dev))
> +		return iommu_dma_coherent_map_page(dev, page, offset, size,
> +				dir, attrs);
> +
> +	dev_addr = iommu_dma_map_page(dev, page, offset, size, dir, attrs);
> +	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
> +		__iommu_sync_single_for_device(dev, dev_addr, size, dir);
> +
> +	return dev_addr;
> +}
> +
> +static void __iommu_unmap_page(struct device *dev, dma_addr_t dev_addr,
> +			       size_t size, enum dma_data_direction dir,
> +			       struct dma_attrs *attrs)
> +{
> +	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
> +		__iommu_sync_single_for_cpu(dev, dev_addr, size, dir);
> +
> +	iommu_dma_unmap_page(dev, dev_addr, size, dir, attrs);
> +}
> +
> +static void __iommu_sync_sg_for_cpu(struct device *dev,
> +				    struct scatterlist *sgl, int nelems,
> +				    enum dma_data_direction dir)
> +{
> +	struct scatterlist *sg;
> +	int i;
> +
> +	if (is_device_dma_coherent(dev))
> +		return;
> +
> +	for_each_sg(sgl, sg, nelems, i) {
> +		unsigned int len = sg_dma_len(sg);
> +		void *virt = iova_to_virt(dev, sg_dma_address(sg));
> +
> +		if (virt && len)
> +			__dma_unmap_area(virt, len, dir);
> +	}

The above loop is not correct. You should iterate over memory page 
chunks not the
dma address chunks. There is no guarantee that single dma chunk matches 
respective
chunk in memory. The following version is correct:

for_each_sg(sgl, sg, nelems, i) {
       void *virt = phys_to_virt(page_to_phys(sg_page(sg))) + sg->offset;
       __dma_unmap_area(virt, sg->length, dir);
}

> +}
> +
> +static void __iommu_sync_sg_for_device(struct device *dev,
> +				       struct scatterlist *sgl, int nelems,
> +				       enum dma_data_direction dir)
> +{
> +	struct scatterlist *sg;
> +	int i;
> +
> +	if (is_device_dma_coherent(dev))
> +		return;
> +
> +	for_each_sg(sgl, sg, nelems, i) {
> +		unsigned int len = sg_dma_len(sg);
> +		void *virt = iova_to_virt(dev, sg_dma_address(sg));
> +
> +		if (virt && len)
> +			__dma_map_area(virt, len, dir);
> +	}

Same as for __iommu_sync_sg_for_cpu().

> +}
> +
> +static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
> +				int nelems, enum dma_data_direction dir,
> +				struct dma_attrs *attrs)
> +{
> +	int count;
> +
> +	if (is_device_dma_coherent(dev))
> +		return iommu_dma_coherent_map_sg(dev, sgl, nelems, dir, attrs);
> +
> +	count = iommu_dma_map_sg(dev, sgl, nelems, dir, attrs);
> +	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
> +		__iommu_sync_sg_for_device(dev, sgl, count, dir);
> +
> +	return count;
> +}
> +
> +static void __iommu_unmap_sg_attrs(struct device *dev,
> +				   struct scatterlist *sgl, int nelems,
> +				   enum dma_data_direction dir,
> +				   struct dma_attrs *attrs)
> +{
> +	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
> +		__iommu_sync_sg_for_cpu(dev, sgl, nelems, dir);
> +
> +	iommu_dma_unmap_sg(dev, sgl, nelems, dir, attrs);
> +}
> +
> +static struct dma_map_ops iommu_dma_ops = {
> +	.alloc = __iommu_alloc_attrs,
> +	.free = __iommu_free_attrs,
> +	.mmap = __swiotlb_mmap,

This one is definitely not correct and it will cause kernel ops/bus 
error. Please
refer to arch/arm iommu_mmap() implementation.

> +	.map_page = __iommu_map_page,
> +	.unmap_page = __iommu_unmap_page,
> +	.map_sg = __iommu_map_sg_attrs,
> +	.unmap_sg = __iommu_unmap_sg_attrs,
> +	.sync_single_for_cpu = __iommu_sync_single_for_cpu,
> +	.sync_single_for_device = __iommu_sync_single_for_device,
> +	.sync_sg_for_cpu = __iommu_sync_sg_for_cpu,
> +	.sync_sg_for_device = __iommu_sync_sg_for_device,
> +	.dma_supported = iommu_dma_supported,
> +	.mapping_error = iommu_dma_mapping_error,

.get_sgtable is missing and it is definitely needed for the iommu based 
implementation.

> +};
> +
> +static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> +				  struct iommu_ops *ops)
> +{
> +	struct iommu_dma_mapping *mapping;
> +
> +	if (!ops)
> +		return;
> +
> +	mapping = iommu_dma_create_mapping(ops, dma_base, size);
> +	if (!mapping) {
> +		pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",
> +				size, dev_name(dev));
> +		return;
> +	}
> +
> +	if (iommu_dma_attach_device(dev, mapping))
> +		pr_warn("Failed to attach device %s to IOMMU mapping\n",
> +				dev_name(dev));
> +	else
> +		dev->archdata.dma_ops = &iommu_dma_ops;
> +
> +	/* drop the initial mapping refcount */
> +	iommu_dma_release_mapping(mapping);
> +}
> +
> +#else
> +
> +static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> +				  struct iommu_ops *iommu)
> +{ }
> +
> +#endif  /* CONFIG_IOMMU_DMA */

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland

[RFC PATCH 5/5] arm64: hook up IOMMU dma_ops

[Robin Murphy]

With iommu_dma_ops in place, hook them up to the configuration code, so
IOMMU-fronted devices will get them automatically.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 arch/arm64/Kconfig                   |  1 +
 arch/arm64/include/asm/dma-mapping.h | 10 +++++-----
 arch/arm64/mm/dma-mapping.c          | 22 ++++++++++++++++++++++
 3 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b1f9a20..e2abcdc 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -66,6 +66,7 @@ config ARM64
 	select HAVE_PERF_USER_STACK_DUMP
 	select HAVE_RCU_TABLE_FREE
 	select HAVE_SYSCALL_TRACEPOINTS
+	select IOMMU_DMA if IOMMU_SUPPORT
 	select IRQ_DOMAIN
 	select MODULES_USE_ELF_RELA
 	select NO_BOOTMEM
diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h
index 82082c4..0791a78 100644
--- a/arch/arm64/include/asm/dma-mapping.h
+++ b/arch/arm64/include/asm/dma-mapping.h
@@ -45,13 +45,13 @@ static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 		return __generic_dma_ops(dev);
 }
 
-static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-				      struct iommu_ops *iommu, bool coherent)
-{
-	dev->archdata.dma_coherent = coherent;
-}
+void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+			struct iommu_ops *iommu, bool coherent);
 #define arch_setup_dma_ops	arch_setup_dma_ops
 
+void arch_teardown_dma_ops(struct device *dev);
+#define arch_teardown_dma_ops	arch_teardown_dma_ops
+
 /* do not use this function in a driver */
 static inline bool is_device_dma_coherent(struct device *dev)
 {
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 8e449a7..d52175d 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -729,10 +729,32 @@ static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 	iommu_dma_release_mapping(mapping);
 }
 
+static void __iommu_teardown_dma_ops(struct device *dev)
+{
+	if (dev->archdata.mapping) {
+		iommu_dma_detach_device(dev);
+		dev->archdata.dma_ops = NULL;
+	}
+}
+
 #else
 
 static void __iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 				  struct iommu_ops *iommu)
 { }
 
+static void __iommu_teardown_dma_ops(struct device *dev) { }
+
 #endif  /* CONFIG_IOMMU_DMA */
+
+void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+			struct iommu_ops *iommu, bool coherent)
+{
+	dev->archdata.dma_coherent = coherent;
+	__iommu_setup_dma_ops(dev, dma_base, size, iommu);
+}
+
+void arch_teardown_dma_ops(struct device *dev)
+{
+	__iommu_teardown_dma_ops(dev);
+}
-- 
1.9.1

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Yingjoe Chen]

On Mon, 2015-01-12 at 20:48 +0000, Robin Murphy wrote:
> Hi all,
> 
> Whilst it's a long way off perfect, this has reached the point of being
> functional and stable enough to be useful, so here it is. The core
> consists of the meat of the arch/arm implementation modified to remove
> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
> allocator instead of the bitmap-based one. For that, this series depends
> on my "Genericise the IOVA allocator" series posted earlier[1].

Hi Robin,

We'd to give it a try. Do you have a public git tree contains both
series?

Joe.C

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Robin Murphy]

On 13/01/15 08:02, Yingjoe Chen wrote:
> On Mon, 2015-01-12 at 20:48 +0000, Robin Murphy wrote:
>> Hi all,
>>
>> Whilst it's a long way off perfect, this has reached the point of being
>> functional and stable enough to be useful, so here it is. The core
>> consists of the meat of the arch/arm implementation modified to remove
>> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
>> allocator instead of the bitmap-based one. For that, this series depends
>> on my "Genericise the IOVA allocator" series posted earlier[1].
>
> Hi Robin,
>
> We'd to give it a try. Do you have a public git tree contains both
> series?
>

Thanks! Unfortunately I don't have a public tree yet, but I'll try to 
get one set up shortly.

Robin.

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Robin Murphy]

On 13/01/15 08:02, Yingjoe Chen wrote:
> On Mon, 2015-01-12 at 20:48 +0000, Robin Murphy wrote:
>> Hi all,
>>
>> Whilst it's a long way off perfect, this has reached the point of being
>> functional and stable enough to be useful, so here it is. The core
>> consists of the meat of the arch/arm implementation modified to remove
>> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
>> allocator instead of the bitmap-based one. For that, this series depends
>> on my "Genericise the IOVA allocator" series posted earlier[1].
>
> Hi Robin,
>
> We'd to give it a try. Do you have a public git tree contains both
> series?
>
> Joe.C

Now that the server seems to be properly accessible again, I've made a 
branch with both series available here:

   git://linux-arm.org/linux-rm iommu/dma

Note that in the current state it also depends on having the ARM SMMU 
driver selected in the config, due to an oversight on my part :(

Robin.

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Yong Wu]

On Thu, 2015-01-15 at 18:35 +0000, Robin Murphy wrote:
> On 13/01/15 08:02, Yingjoe Chen wrote:
> > On Mon, 2015-01-12 at 20:48 +0000, Robin Murphy wrote:
> >> Hi all,
> >>
> >> Whilst it's a long way off perfect, this has reached the point of being
> >> functional and stable enough to be useful, so here it is. The core
> >> consists of the meat of the arch/arm implementation modified to remove
> >> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
> >> allocator instead of the bitmap-based one. For that, this series depends
> >> on my "Genericise the IOVA allocator" series posted earlier[1].
> >
> > Hi Robin,
> >
> > We'd to give it a try. Do you have a public git tree contains both
> > series?
> >
> > Joe.C
> 
> Now that the server seems to be properly accessible again, I've made a 
> branch with both series available here:
> 
>    git://linux-arm.org/linux-rm iommu/dma
> 
> Note that in the current state it also depends on having the ARM SMMU 
> driver selected in the config, due to an oversight on my part :(
> 
> Robin.
> 
Dear Robin,

     We have test this patch on our SOC(mt8173),which have our own iommu
HW(it is not ARM SMMU), the patch could work well.
Tested-by:Yong Wu <yong.wu@mediatek.com>

 And I have some questiones about the usage:

1) If we create a iommu domain by ?arch_setup_dma_ops", then we would
like to call the standard iommu interface, like
?iommu_set_fault_handle?,
How can we get the "struct iommu_domain *"? (the ?dev_domain? is
static.)

2) If a device A call ?arch_setup_dma_ops? to create a iommu domain, and
a client device B would like to join this iommu domain, 
so it call ?iommu_dma_attach_device?. then the device B want to alloc
the iommu memory, it call ?dma_alloc_attrs? whose first parameter should
be the ?struct device *?of device A. Is it designed like this in this
patch?
    (In arch/arm, ?dev->archdata.dma_ops = &iommu_dma_ops? is in
?arm_iommu_attach_devce?;
     In this patch, this sentence is in ?arch_setup_dma_ops?).

3)  void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
struct iommu_ops *iommu, bool coherent)
    In this function, the second and third parameter are the dma address
base and size, can they work currently?
(take a example, I set the dma_base is 0, size is 0x40000000 while
calling arch_setup_dma_ops, 
 then I alloc a range iova whose size is 50*SZ_4K, the return iova is
0xfffce000, it is over 0x40000000.)

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Robin Murphy]

On 16/01/15 07:21, Yong Wu wrote:
[...]
>> Now that the server seems to be properly accessible again, I've made a
>> branch with both series available here:
>>
>>     git://linux-arm.org/linux-rm iommu/dma
>>
>> Note that in the current state it also depends on having the ARM SMMU
>> driver selected in the config, due to an oversight on my part :(
>>
>> Robin.
>>
> Dear Robin,
>
>       We have test this patch on our SOC(mt8173),which have our own iommu
> HW(it is not ARM SMMU), the patch could work well.
> Tested-by:Yong Wu <yong.wu@mediatek.com>
>

Thanks!

>   And I have some questiones about the usage:
>
> 1) If we create a iommu domain by ?arch_setup_dma_ops", then we would
> like to call the standard iommu interface, like
> ?iommu_set_fault_handle?,
> How can we get the "struct iommu_domain *"? (the ?dev_domain? is
> static.)
>
> 2) If a device A call ?arch_setup_dma_ops? to create a iommu domain, and
> a client device B would like to join this iommu domain,
> so it call ?iommu_dma_attach_device?. then the device B want to alloc
> the iommu memory, it call ?dma_alloc_attrs? whose first parameter should
> be the ?struct device *?of device A. Is it designed like this in this
> patch?
>      (In arch/arm, ?dev->archdata.dma_ops = &iommu_dma_ops? is in
> ?arm_iommu_attach_devce?;
>       In this patch, this sentence is in ?arch_setup_dma_ops?).
>

At this point there's not really any support for devices managing their 
own IOMMUs - initially I've only been focusing on the case where 
dma-mapping handles everything transparently, with legacy 32-bit 
peripherals in mind. There's already been quite a lot of discussion over 
the shortcomings of the current arch_setup_dma_ops model (most recently, 
[1]), but it just-about-works on Juno where we have a single device 
behind each IOMMU (with the exception of the USB OHCI which falls foul 
of the domain-per-device approach and falls over because it can't 
understand addresses from the EHCI). We really need to get IOMMU groups 
working in order to manage domains properly, which for one thing 
requires fixing the current situation of devices getting attached to a 
domain before they've even been added to the bus. I've started looking 
into that, but I suspect it's going to be long and complicated.

> 3)  void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
> struct iommu_ops *iommu, bool coherent)
>      In this function, the second and third parameter are the dma address
> base and size, can they work currently?
> (take a example, I set the dma_base is 0, size is 0x40000000 while
> calling arch_setup_dma_ops,
>   then I alloc a range iova whose size is 50*SZ_4K, the return iova is
> 0xfffce000, it is over 0x40000000.)
>

That'll be coming from __alloc_iova using the device's dma_mask as an 
upper limit. Whilst I'm not sure if having fixed translations per 
dma-ranges makes sense with an IOMMU present, there does seem to be a 
valid case for having a size smaller than the driver's dma_mask - e.g. a 
device that just happens to have some upper address lines tied off in a 
particular implementation - so I'll change that to properly respect the 
dma-ranges values.

Robin.

[1]:http://thread.gmane.org/gmane.linux.kernel.iommu/7556/focus=8237

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Stefano Stabellini]

On Mon, 12 Jan 2015, Robin Murphy wrote:
> Hi all,
> 
> Whilst it's a long way off perfect, this has reached the point of being
> functional and stable enough to be useful, so here it is. The core
> consists of the meat of the arch/arm implementation modified to remove
> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
> allocator instead of the bitmap-based one. For that, this series depends
> on my "Genericise the IOVA allocator" series posted earlier[1].
> 
> There are plenty of obvious things still to do, including:
> 
>  * Domain and group handling is all wrong, but that's a bigger problem.
>    For the moment it does more or less the same thing as the arch/arm
>    code, which at least works for the one-IOMMU-per-device situation.
>  * IOMMU domains and IOVA domains probably want to be better integrated
>    with devices and each other, rather than having a proliferation of
>    arch-specific structs.
>  * The temporary map_sg implementation - I have a 'proper' iommu_map_sg
>    based one in progress, but since the simple one works it's not been
>    as high a priority.
>  * Port arch/arm over to it. I'd guess it might be preferable to merge
>    this through arm64 first, though, rather than overcomplicate matters.
>  * There may well be scope for streamlining and tidying up the copied
>    parts - In general I've simply avoided touching anything I don't
>    fully understand.
>  * In the same vein, I'm sure lots of it is fairly ARM-specific, so will
>    need longer-term work to become truly generic.
> 
> [1]:http://thread.gmane.org/gmane.linux.kernel.iommu/8208

I tried to git-am and build a v3.19-rc4 kernel with this series (config
file attached), but I get:

In file included from include/linux/dma-mapping.h:82:0,
                 from arch/arm64/kernel/asm-offsets.c:23:
./arch/arm64/include/asm/dma-mapping.h: In function ?phys_to_dma?:
./arch/arm64/include/asm/dma-mapping.h:69:2: error: ?struct dev_archdata? has no member named ?mapping?
./arch/arm64/include/asm/dma-mapping.h: In function ?dma_to_phys?:
./arch/arm64/include/asm/dma-mapping.h:81:19: error: ?struct dev_archdata? has no member named ?mapping?
make[1]: *** [arch/arm64/kernel/asm-offsets.s] Error 1
-------------- next part --------------
#
# Automatically generated file; DO NOT EDIT.
# Linux/arm64 3.19.0-rc4 Kernel Configuration
#
CONFIG_ARM64=y
CONFIG_64BIT=y
CONFIG_ARCH_PHYS_ADDR_T_64BIT=y
CONFIG_MMU=y
CONFIG_STACKTRACE_SUPPORT=y
CONFIG_LOCKDEP_SUPPORT=y
CONFIG_TRACE_IRQFLAGS_SUPPORT=y
CONFIG_RWSEM_XCHGADD_ALGORITHM=y
CONFIG_GENERIC_HWEIGHT=y
CONFIG_GENERIC_CSUM=y
CONFIG_GENERIC_CALIBRATE_DELAY=y
CONFIG_ZONE_DMA=y
CONFIG_HAVE_GENERIC_RCU_GUP=y
CONFIG_ARCH_DMA_ADDR_T_64BIT=y
CONFIG_NEED_DMA_MAP_STATE=y
CONFIG_NEED_SG_DMA_LENGTH=y
CONFIG_SWIOTLB=y
CONFIG_IOMMU_HELPER=y
CONFIG_KERNEL_MODE_NEON=y
CONFIG_FIX_EARLYCON_MEM=y
CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"
CONFIG_IRQ_WORK=y
CONFIG_BUILDTIME_EXTABLE_SORT=y

#
# General setup
#
CONFIG_INIT_ENV_ARG_LIMIT=32
CONFIG_CROSS_COMPILE=""
# CONFIG_COMPILE_TEST is not set
CONFIG_LOCALVERSION=""
# CONFIG_LOCALVERSION_AUTO is not set
CONFIG_DEFAULT_HOSTNAME="(none)"
CONFIG_SWAP=y
CONFIG_SYSVIPC=y
CONFIG_SYSVIPC_SYSCTL=y
# CONFIG_POSIX_MQUEUE is not set
CONFIG_CROSS_MEMORY_ATTACH=y
# CONFIG_FHANDLE is not set
CONFIG_USELIB=y
# CONFIG_AUDIT is not set
CONFIG_HAVE_ARCH_AUDITSYSCALL=y

#
# IRQ subsystem
#
CONFIG_GENERIC_IRQ_PROBE=y
CONFIG_GENERIC_IRQ_SHOW=y
CONFIG_HARDIRQS_SW_RESEND=y
CONFIG_IRQ_DOMAIN=y
CONFIG_IRQ_DOMAIN_HIERARCHY=y
CONFIG_GENERIC_MSI_IRQ=y
CONFIG_GENERIC_MSI_IRQ_DOMAIN=y
CONFIG_HANDLE_DOMAIN_IRQ=y
# CONFIG_IRQ_DOMAIN_DEBUG is not set
CONFIG_SPARSE_IRQ=y
CONFIG_GENERIC_TIME_VSYSCALL=y
CONFIG_GENERIC_CLOCKEVENTS=y
CONFIG_GENERIC_CLOCKEVENTS_BUILD=y
CONFIG_ARCH_HAS_TICK_BROADCAST=y
CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y

#
# Timers subsystem
#
CONFIG_TICK_ONESHOT=y
CONFIG_NO_HZ_COMMON=y
# CONFIG_HZ_PERIODIC is not set
CONFIG_NO_HZ_IDLE=y
# CONFIG_NO_HZ_FULL is not set
CONFIG_NO_HZ=y
CONFIG_HIGH_RES_TIMERS=y

#
# CPU/Task time and stats accounting
#
CONFIG_TICK_CPU_ACCOUNTING=y
# CONFIG_VIRT_CPU_ACCOUNTING_GEN is not set
# CONFIG_BSD_PROCESS_ACCT is not set
# CONFIG_TASKSTATS is not set

#
# RCU Subsystem
#
CONFIG_TREE_RCU=y
# CONFIG_TASKS_RCU is not set
CONFIG_RCU_STALL_COMMON=y
# CONFIG_RCU_USER_QS is not set
CONFIG_RCU_FANOUT=32
CONFIG_RCU_FANOUT_LEAF=16
# CONFIG_RCU_FANOUT_EXACT is not set
# CONFIG_RCU_FAST_NO_HZ is not set
# CONFIG_TREE_RCU_TRACE is not set
# CONFIG_RCU_NOCB_CPU is not set
# CONFIG_BUILD_BIN2C is not set
# CONFIG_IKCONFIG is not set
CONFIG_LOG_BUF_SHIFT=14
CONFIG_LOG_CPU_MAX_BUF_SHIFT=12
CONFIG_GENERIC_SCHED_CLOCK=y
# CONFIG_CGROUPS is not set
# CONFIG_CHECKPOINT_RESTORE is not set
CONFIG_NAMESPACES=y
CONFIG_UTS_NS=y
CONFIG_IPC_NS=y
# CONFIG_USER_NS is not set
CONFIG_PID_NS=y
CONFIG_NET_NS=y
# CONFIG_SCHED_AUTOGROUP is not set
# CONFIG_SYSFS_DEPRECATED is not set
# CONFIG_RELAY is not set
CONFIG_BLK_DEV_INITRD=y
CONFIG_INITRAMFS_SOURCE=""
CONFIG_RD_GZIP=y
# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
# CONFIG_RD_LZ4 is not set
CONFIG_INIT_FALLBACK=y
CONFIG_CC_OPTIMIZE_FOR_SIZE=y
CONFIG_SYSCTL=y
CONFIG_ANON_INODES=y
CONFIG_SYSCTL_EXCEPTION_TRACE=y
CONFIG_BPF=y
CONFIG_EXPERT=y
# CONFIG_SGETMASK_SYSCALL is not set
CONFIG_SYSFS_SYSCALL=y
# CONFIG_SYSCTL_SYSCALL is not set
CONFIG_KALLSYMS=y
# CONFIG_KALLSYMS_ALL is not set
CONFIG_PRINTK=y
CONFIG_BUG=y
CONFIG_ELF_CORE=y
CONFIG_BASE_FULL=y
CONFIG_FUTEX=y
CONFIG_EPOLL=y
CONFIG_SIGNALFD=y
CONFIG_TIMERFD=y
CONFIG_EVENTFD=y
# CONFIG_BPF_SYSCALL is not set
CONFIG_SHMEM=y
CONFIG_AIO=y
CONFIG_ADVISE_SYSCALLS=y
CONFIG_PCI_QUIRKS=y
# CONFIG_EMBEDDED is not set
CONFIG_HAVE_PERF_EVENTS=y
CONFIG_PERF_USE_VMALLOC=y

#
# Kernel Performance Events And Counters
#
# CONFIG_PERF_EVENTS is not set
CONFIG_VM_EVENT_COUNTERS=y
CONFIG_COMPAT_BRK=y
CONFIG_SLAB=y
# CONFIG_SLUB is not set
# CONFIG_SLOB is not set
# CONFIG_PROFILING is not set
# CONFIG_JUMP_LABEL is not set
# CONFIG_UPROBES is not set
# CONFIG_HAVE_64BIT_ALIGNED_ACCESS is not set
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y
CONFIG_HAVE_ARCH_TRACEHOOK=y
CONFIG_HAVE_DMA_ATTRS=y
CONFIG_HAVE_DMA_CONTIGUOUS=y
CONFIG_GENERIC_SMP_IDLE_THREAD=y
CONFIG_HAVE_CLK=y
CONFIG_HAVE_DMA_API_DEBUG=y
CONFIG_HAVE_PERF_REGS=y
CONFIG_HAVE_PERF_USER_STACK_DUMP=y
CONFIG_HAVE_ARCH_JUMP_LABEL=y
CONFIG_HAVE_RCU_TABLE_FREE=y
CONFIG_HAVE_CMPXCHG_DOUBLE=y
CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION=y
CONFIG_HAVE_ARCH_SECCOMP_FILTER=y
CONFIG_HAVE_CC_STACKPROTECTOR=y
# CONFIG_CC_STACKPROTECTOR is not set
CONFIG_CC_STACKPROTECTOR_NONE=y
# CONFIG_CC_STACKPROTECTOR_REGULAR is not set
# CONFIG_CC_STACKPROTECTOR_STRONG is not set
CONFIG_HAVE_CONTEXT_TRACKING=y
CONFIG_HAVE_VIRT_CPU_ACCOUNTING_GEN=y
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
CONFIG_MODULES_USE_ELF_RELA=y
CONFIG_CLONE_BACKWARDS=y

#
# GCOV-based kernel profiling
#
# CONFIG_GCOV_KERNEL is not set
CONFIG_ARCH_HAS_GCOV_PROFILE_ALL=y
CONFIG_HAVE_GENERIC_DMA_COHERENT=y
CONFIG_SLABINFO=y
CONFIG_RT_MUTEXES=y
CONFIG_BASE_SMALL=0
# CONFIG_MODULES is not set
CONFIG_STOP_MACHINE=y
CONFIG_BLOCK=y
CONFIG_BLK_DEV_BSG=y
# CONFIG_BLK_DEV_BSGLIB is not set
# CONFIG_BLK_DEV_INTEGRITY is not set
# CONFIG_BLK_CMDLINE_PARSER is not set

#
# Partition Types
#
CONFIG_PARTITION_ADVANCED=y
# CONFIG_ACORN_PARTITION is not set
# CONFIG_AIX_PARTITION is not set
# CONFIG_OSF_PARTITION is not set
# CONFIG_AMIGA_PARTITION is not set
# CONFIG_ATARI_PARTITION is not set
# CONFIG_MAC_PARTITION is not set
CONFIG_MSDOS_PARTITION=y
# CONFIG_BSD_DISKLABEL is not set
# CONFIG_MINIX_SUBPARTITION is not set
# CONFIG_SOLARIS_X86_PARTITION is not set
# CONFIG_UNIXWARE_DISKLABEL is not set
# CONFIG_LDM_PARTITION is not set
# CONFIG_SGI_PARTITION is not set
# CONFIG_ULTRIX_PARTITION is not set
# CONFIG_SUN_PARTITION is not set
# CONFIG_KARMA_PARTITION is not set
# CONFIG_EFI_PARTITION is not set
# CONFIG_SYSV68_PARTITION is not set
# CONFIG_CMDLINE_PARTITION is not set

#
# IO Schedulers
#
CONFIG_IOSCHED_NOOP=y
CONFIG_IOSCHED_DEADLINE=y
CONFIG_IOSCHED_CFQ=y
# CONFIG_DEFAULT_DEADLINE is not set
CONFIG_DEFAULT_CFQ=y
# CONFIG_DEFAULT_NOOP is not set
CONFIG_DEFAULT_IOSCHED="cfq"
CONFIG_INLINE_SPIN_UNLOCK_IRQ=y
CONFIG_INLINE_READ_UNLOCK=y
CONFIG_INLINE_READ_UNLOCK_IRQ=y
CONFIG_INLINE_WRITE_UNLOCK=y
CONFIG_INLINE_WRITE_UNLOCK_IRQ=y
CONFIG_ARCH_SUPPORTS_ATOMIC_RMW=y
CONFIG_MUTEX_SPIN_ON_OWNER=y
CONFIG_RWSEM_SPIN_ON_OWNER=y
CONFIG_FREEZER=y

#
# Platform selection
#
# CONFIG_ARCH_SEATTLE is not set
# CONFIG_ARCH_THUNDER is not set
CONFIG_ARCH_VEXPRESS=y
CONFIG_ARCH_XGENE=y

#
# Bus support
#
CONFIG_PCI=y
CONFIG_PCI_DOMAINS=y
CONFIG_PCI_DOMAINS_GENERIC=y
CONFIG_PCI_SYSCALL=y
CONFIG_PCI_MSI=y
CONFIG_PCI_MSI_IRQ_DOMAIN=y
# CONFIG_PCI_DEBUG is not set
# CONFIG_PCI_REALLOC_ENABLE_AUTO is not set
# CONFIG_PCI_STUB is not set
# CONFIG_PCI_IOV is not set
# CONFIG_PCI_PRI is not set
# CONFIG_PCI_PASID is not set
CONFIG_PCI_LABEL=y

#
# PCI host controller drivers
#
CONFIG_PCI_XGENE=y
CONFIG_PCIEPORTBUS=y
CONFIG_PCIEAER=y
# CONFIG_PCIE_ECRC is not set
# CONFIG_PCIEAER_INJECT is not set
CONFIG_PCIEASPM=y
# CONFIG_PCIEASPM_DEBUG is not set
CONFIG_PCIEASPM_DEFAULT=y
# CONFIG_PCIEASPM_POWERSAVE is not set
# CONFIG_PCIEASPM_PERFORMANCE is not set
CONFIG_PCIE_PME=y
# CONFIG_HOTPLUG_PCI is not set

#
# Kernel Features
#

#
# ARM errata workarounds via the alternatives framework
#
CONFIG_ARM64_ERRATUM_826319=y
CONFIG_ARM64_ERRATUM_827319=y
CONFIG_ARM64_ERRATUM_824069=y
CONFIG_ARM64_ERRATUM_819472=y
CONFIG_ARM64_ERRATUM_832075=y
CONFIG_ARM64_4K_PAGES=y
# CONFIG_ARM64_64K_PAGES is not set
CONFIG_ARM64_VA_BITS_39=y
# CONFIG_ARM64_VA_BITS_48 is not set
CONFIG_ARM64_VA_BITS=39
CONFIG_ARM64_PGTABLE_LEVELS=3
# CONFIG_CPU_BIG_ENDIAN is not set
CONFIG_SMP=y
# CONFIG_SCHED_MC is not set
# CONFIG_SCHED_SMT is not set
CONFIG_NR_CPUS=4
CONFIG_HOTPLUG_CPU=y
CONFIG_PREEMPT_NONE=y
# CONFIG_PREEMPT_VOLUNTARY is not set
# CONFIG_PREEMPT is not set
CONFIG_HZ=100
CONFIG_ARCH_HAS_HOLES_MEMORYMODEL=y
CONFIG_ARCH_SPARSEMEM_ENABLE=y
CONFIG_ARCH_SPARSEMEM_DEFAULT=y
CONFIG_ARCH_SELECT_MEMORY_MODEL=y
CONFIG_HAVE_ARCH_PFN_VALID=y
CONFIG_SYS_SUPPORTS_HUGETLBFS=y
CONFIG_ARCH_WANT_GENERAL_HUGETLB=y
CONFIG_ARCH_WANT_HUGE_PMD_SHARE=y
CONFIG_ARCH_HAS_CACHE_LINE_SIZE=y
CONFIG_SELECT_MEMORY_MODEL=y
CONFIG_SPARSEMEM_MANUAL=y
CONFIG_SPARSEMEM=y
CONFIG_HAVE_MEMORY_PRESENT=y
CONFIG_SPARSEMEM_EXTREME=y
CONFIG_SPARSEMEM_VMEMMAP_ENABLE=y
CONFIG_SPARSEMEM_VMEMMAP=y
CONFIG_HAVE_MEMBLOCK=y
CONFIG_NO_BOOTMEM=y
# CONFIG_HAVE_BOOTMEM_INFO_NODE is not set
CONFIG_PAGEFLAGS_EXTENDED=y
CONFIG_SPLIT_PTLOCK_CPUS=4
CONFIG_COMPACTION=y
CONFIG_MIGRATION=y
CONFIG_PHYS_ADDR_T_64BIT=y
CONFIG_ZONE_DMA_FLAG=1
CONFIG_BOUNCE=y
CONFIG_MMU_NOTIFIER=y
# CONFIG_KSM is not set
CONFIG_DEFAULT_MMAP_MIN_ADDR=4096
# CONFIG_TRANSPARENT_HUGEPAGE is not set
# CONFIG_CLEANCACHE is not set
# CONFIG_FRONTSWAP is not set
# CONFIG_CMA is not set
# CONFIG_ZPOOL is not set
# CONFIG_ZBUD is not set
# CONFIG_ZSMALLOC is not set
CONFIG_GENERIC_EARLY_IOREMAP=y
# CONFIG_SECCOMP is not set
CONFIG_XEN_DOM0=y
CONFIG_XEN=y
CONFIG_FORCE_MAX_ZONEORDER=11

#
# Boot options
#
CONFIG_CMDLINE="earlyprintk=xenboot console=ttyAMA1 root=/dev/mmcblk0 debug rw init=/bin/bash"
# CONFIG_CMDLINE_FORCE is not set
CONFIG_EFI_STUB=y
CONFIG_EFI=y
CONFIG_DMI=y

#
# Userspace binary formats
#
CONFIG_BINFMT_ELF=y
CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE=y
CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS=y
CONFIG_BINFMT_SCRIPT=y
# CONFIG_HAVE_AOUT is not set
CONFIG_BINFMT_MISC=y
CONFIG_COREDUMP=y
# CONFIG_COMPAT is not set

#
# Power management options
#
CONFIG_SUSPEND=y
CONFIG_SUSPEND_FREEZER=y
CONFIG_PM_SLEEP=y
CONFIG_PM_SLEEP_SMP=y
# CONFIG_PM_AUTOSLEEP is not set
# CONFIG_PM_WAKELOCKS is not set
CONFIG_PM=y
# CONFIG_PM_DEBUG is not set
CONFIG_PM_CLK=y
# CONFIG_WQ_POWER_EFFICIENT_DEFAULT is not set
CONFIG_CPU_PM=y
CONFIG_ARCH_SUSPEND_POSSIBLE=y
CONFIG_ARM64_CPU_SUSPEND=y

#
# CPU Power Management
#

#
# CPU Idle
#
# CONFIG_CPU_IDLE is not set
# CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED is not set

#
# CPU Frequency scaling
#
# CONFIG_CPU_FREQ is not set
CONFIG_NET=y

#
# Networking options
#
CONFIG_PACKET=y
# CONFIG_PACKET_DIAG is not set
CONFIG_UNIX=y
# CONFIG_UNIX_DIAG is not set
CONFIG_XFRM=y
# CONFIG_XFRM_USER is not set
# CONFIG_XFRM_SUB_POLICY is not set
# CONFIG_XFRM_MIGRATE is not set
# CONFIG_XFRM_STATISTICS is not set
# CONFIG_NET_KEY is not set
CONFIG_INET=y
CONFIG_IP_MULTICAST=y
# CONFIG_IP_ADVANCED_ROUTER is not set
CONFIG_IP_PNP=y
# CONFIG_IP_PNP_DHCP is not set
CONFIG_IP_PNP_BOOTP=y
# CONFIG_IP_PNP_RARP is not set
# CONFIG_NET_IPIP is not set
# CONFIG_NET_IPGRE_DEMUX is not set
# CONFIG_NET_IP_TUNNEL is not set
# CONFIG_IP_MROUTE is not set
# CONFIG_SYN_COOKIES is not set
# CONFIG_NET_IPVTI is not set
# CONFIG_NET_UDP_TUNNEL is not set
# CONFIG_NET_FOU is not set
# CONFIG_GENEVE is not set
# CONFIG_INET_AH is not set
# CONFIG_INET_ESP is not set
# CONFIG_INET_IPCOMP is not set
# CONFIG_INET_XFRM_TUNNEL is not set
# CONFIG_INET_TUNNEL is not set
CONFIG_INET_XFRM_MODE_TRANSPORT=y
CONFIG_INET_XFRM_MODE_TUNNEL=y
CONFIG_INET_XFRM_MODE_BEET=y
CONFIG_INET_LRO=y
# CONFIG_INET_DIAG is not set
# CONFIG_TCP_CONG_ADVANCED is not set
CONFIG_TCP_CONG_CUBIC=y
CONFIG_DEFAULT_TCP_CONG="cubic"
# CONFIG_TCP_MD5SIG is not set
# CONFIG_IPV6 is not set
# CONFIG_NETWORK_SECMARK is not set
# CONFIG_NET_PTP_CLASSIFY is not set
# CONFIG_NETWORK_PHY_TIMESTAMPING is not set
# CONFIG_NETFILTER is not set
# CONFIG_IP_DCCP is not set
# CONFIG_IP_SCTP is not set
# CONFIG_RDS is not set
# CONFIG_TIPC is not set
# CONFIG_ATM is not set
# CONFIG_L2TP is not set
CONFIG_STP=y
CONFIG_BRIDGE=y
CONFIG_BRIDGE_IGMP_SNOOPING=y
CONFIG_HAVE_NET_DSA=y
# CONFIG_VLAN_8021Q is not set
# CONFIG_DECNET is not set
CONFIG_LLC=y
# CONFIG_LLC2 is not set
# CONFIG_IPX is not set
# CONFIG_ATALK is not set
# CONFIG_X25 is not set
# CONFIG_LAPB is not set
# CONFIG_PHONET is not set
# CONFIG_IEEE802154 is not set
# CONFIG_NET_SCHED is not set
# CONFIG_DCB is not set
# CONFIG_BATMAN_ADV is not set
# CONFIG_OPENVSWITCH is not set
# CONFIG_VSOCKETS is not set
# CONFIG_NETLINK_MMAP is not set
# CONFIG_NETLINK_DIAG is not set
# CONFIG_NET_MPLS_GSO is not set
# CONFIG_HSR is not set
# CONFIG_NET_SWITCHDEV is not set
CONFIG_RPS=y
CONFIG_RFS_ACCEL=y
CONFIG_XPS=y
CONFIG_NET_RX_BUSY_POLL=y
CONFIG_BQL=y
CONFIG_NET_FLOW_LIMIT=y

#
# Network testing
#
# CONFIG_NET_PKTGEN is not set
# CONFIG_HAMRADIO is not set
# CONFIG_CAN is not set
# CONFIG_IRDA is not set
# CONFIG_BT is not set
# CONFIG_AF_RXRPC is not set
CONFIG_WIRELESS=y
# CONFIG_CFG80211 is not set
# CONFIG_LIB80211 is not set

#
# CFG80211 needs to be enabled for MAC80211
#
# CONFIG_WIMAX is not set
# CONFIG_RFKILL is not set
# CONFIG_NET_9P is not set
# CONFIG_CAIF is not set
# CONFIG_CEPH_LIB is not set
# CONFIG_NFC is not set
CONFIG_HAVE_BPF_JIT=y

#
# Device Drivers
#
CONFIG_ARM_AMBA=y
# CONFIG_TEGRA_AHB is not set

#
# Generic Driver Options
#
CONFIG_UEVENT_HELPER=y
CONFIG_UEVENT_HELPER_PATH=""
# CONFIG_DEVTMPFS is not set
CONFIG_STANDALONE=y
CONFIG_PREVENT_FIRMWARE_BUILD=y
CONFIG_FW_LOADER=y
CONFIG_FIRMWARE_IN_KERNEL=y
CONFIG_EXTRA_FIRMWARE=""
# CONFIG_FW_LOADER_USER_HELPER_FALLBACK is not set
CONFIG_ALLOW_DEV_COREDUMP=y
# CONFIG_DEBUG_DRIVER is not set
# CONFIG_DEBUG_DEVRES is not set
CONFIG_SYS_HYPERVISOR=y
# CONFIG_GENERIC_CPU_DEVICES is not set
CONFIG_GENERIC_CPU_AUTOPROBE=y
CONFIG_REGMAP=y
CONFIG_REGMAP_MMIO=y
# CONFIG_DMA_SHARED_BUFFER is not set

#
# Bus devices
#
CONFIG_VEXPRESS_CONFIG=y
# CONFIG_CONNECTOR is not set
CONFIG_MTD=y
# CONFIG_MTD_REDBOOT_PARTS is not set
CONFIG_MTD_CMDLINE_PARTS=y
# CONFIG_MTD_OF_PARTS is not set
# CONFIG_MTD_AR7_PARTS is not set

#
# User Modules And Translation Layers
#
CONFIG_MTD_BLKDEVS=y
CONFIG_MTD_BLOCK=y
# CONFIG_FTL is not set
# CONFIG_NFTL is not set
# CONFIG_INFTL is not set
# CONFIG_RFD_FTL is not set
# CONFIG_SSFDC is not set
# CONFIG_SM_FTL is not set
# CONFIG_MTD_OOPS is not set
# CONFIG_MTD_SWAP is not set

#
# RAM/ROM/Flash chip drivers
#
CONFIG_MTD_CFI=y
# CONFIG_MTD_JEDECPROBE is not set
CONFIG_MTD_GEN_PROBE=y
CONFIG_MTD_CFI_ADV_OPTIONS=y
CONFIG_MTD_CFI_NOSWAP=y
# CONFIG_MTD_CFI_BE_BYTE_SWAP is not set
# CONFIG_MTD_CFI_LE_BYTE_SWAP is not set
# CONFIG_MTD_CFI_GEOMETRY is not set
CONFIG_MTD_MAP_BANK_WIDTH_1=y
CONFIG_MTD_MAP_BANK_WIDTH_2=y
CONFIG_MTD_MAP_BANK_WIDTH_4=y
# CONFIG_MTD_MAP_BANK_WIDTH_8 is not set
# CONFIG_MTD_MAP_BANK_WIDTH_16 is not set
# CONFIG_MTD_MAP_BANK_WIDTH_32 is not set
CONFIG_MTD_CFI_I1=y
CONFIG_MTD_CFI_I2=y
# CONFIG_MTD_CFI_I4 is not set
# CONFIG_MTD_CFI_I8 is not set
# CONFIG_MTD_OTP is not set
CONFIG_MTD_CFI_INTELEXT=y
# CONFIG_MTD_CFI_AMDSTD is not set
# CONFIG_MTD_CFI_STAA is not set
CONFIG_MTD_CFI_UTIL=y
# CONFIG_MTD_RAM is not set
# CONFIG_MTD_ROM is not set
# CONFIG_MTD_ABSENT is not set

#
# Mapping drivers for chip access
#
# CONFIG_MTD_COMPLEX_MAPPINGS is not set
# CONFIG_MTD_PHYSMAP is not set
# CONFIG_MTD_PHYSMAP_OF is not set
# CONFIG_MTD_INTEL_VR_NOR is not set
# CONFIG_MTD_PLATRAM is not set

#
# Self-contained MTD device drivers
#
# CONFIG_MTD_PMC551 is not set
# CONFIG_MTD_SLRAM is not set
# CONFIG_MTD_PHRAM is not set
# CONFIG_MTD_MTDRAM is not set
# CONFIG_MTD_BLOCK2MTD is not set

#
# Disk-On-Chip Device Drivers
#
# CONFIG_MTD_DOCG3 is not set
# CONFIG_MTD_NAND is not set
# CONFIG_MTD_ONENAND is not set

#
# LPDDR & LPDDR2 PCM memory drivers
#
# CONFIG_MTD_LPDDR is not set
# CONFIG_MTD_SPI_NOR is not set
# CONFIG_MTD_UBI is not set
CONFIG_DTC=y
CONFIG_OF=y

#
# Device Tree and Open Firmware support
#
# CONFIG_OF_UNITTEST is not set
CONFIG_OF_FLATTREE=y
CONFIG_OF_EARLY_FLATTREE=y
CONFIG_OF_ADDRESS=y
CONFIG_OF_ADDRESS_PCI=y
CONFIG_OF_IRQ=y
CONFIG_OF_NET=y
CONFIG_OF_MDIO=y
CONFIG_OF_PCI=y
CONFIG_OF_PCI_IRQ=y
CONFIG_OF_MTD=y
CONFIG_OF_RESERVED_MEM=y
# CONFIG_PARPORT is not set
CONFIG_BLK_DEV=y
# CONFIG_BLK_DEV_NULL_BLK is not set
# CONFIG_BLK_DEV_PCIESSD_MTIP32XX is not set
# CONFIG_BLK_CPQ_CISS_DA is not set
# CONFIG_BLK_DEV_DAC960 is not set
# CONFIG_BLK_DEV_UMEM is not set
# CONFIG_BLK_DEV_COW_COMMON is not set
CONFIG_BLK_DEV_LOOP=y
CONFIG_BLK_DEV_LOOP_MIN_COUNT=8
# CONFIG_BLK_DEV_CRYPTOLOOP is not set
# CONFIG_BLK_DEV_DRBD is not set
# CONFIG_BLK_DEV_NBD is not set
# CONFIG_BLK_DEV_NVME is not set
# CONFIG_BLK_DEV_SKD is not set
# CONFIG_BLK_DEV_SX8 is not set
CONFIG_BLK_DEV_RAM=y
CONFIG_BLK_DEV_RAM_COUNT=16
CONFIG_BLK_DEV_RAM_SIZE=4096
# CONFIG_BLK_DEV_XIP is not set
# CONFIG_CDROM_PKTCDVD is not set
# CONFIG_ATA_OVER_ETH is not set
CONFIG_XEN_BLKDEV_FRONTEND=y
CONFIG_XEN_BLKDEV_BACKEND=y
# CONFIG_BLK_DEV_RBD is not set
# CONFIG_BLK_DEV_RSXX is not set

#
# Misc devices
#
# CONFIG_SENSORS_LIS3LV02D is not set
# CONFIG_AD525X_DPOT is not set
# CONFIG_DUMMY_IRQ is not set
# CONFIG_PHANTOM is not set
# CONFIG_SGI_IOC4 is not set
# CONFIG_TIFM_CORE is not set
# CONFIG_ICS932S401 is not set
# CONFIG_ENCLOSURE_SERVICES is not set
# CONFIG_HP_ILO is not set
# CONFIG_APDS9802ALS is not set
# CONFIG_ISL29003 is not set
# CONFIG_ISL29020 is not set
# CONFIG_SENSORS_TSL2550 is not set
# CONFIG_SENSORS_BH1780 is not set
# CONFIG_SENSORS_BH1770 is not set
# CONFIG_SENSORS_APDS990X is not set
# CONFIG_HMC6352 is not set
# CONFIG_DS1682 is not set
# CONFIG_BMP085_I2C is not set
# CONFIG_USB_SWITCH_FSA9480 is not set
# CONFIG_SRAM is not set
CONFIG_VEXPRESS_SYSCFG=y
# CONFIG_C2PORT is not set

#
# EEPROM support
#
# CONFIG_EEPROM_AT24 is not set
# CONFIG_EEPROM_LEGACY is not set
# CONFIG_EEPROM_MAX6875 is not set
# CONFIG_EEPROM_93CX6 is not set
# CONFIG_CB710_CORE is not set

#
# Texas Instruments shared transport line discipline
#
# CONFIG_TI_ST is not set
# CONFIG_SENSORS_LIS3_I2C is not set

#
# Altera FPGA firmware download module
#
# CONFIG_ALTERA_STAPL is not set

#
# Intel MIC Bus Driver
#

#
# Intel MIC Host Driver
#

#
# Intel MIC Card Driver
#
# CONFIG_GENWQE is not set
# CONFIG_ECHO is not set
# CONFIG_CXL_BASE is not set

#
# SCSI device support
#
CONFIG_SCSI_MOD=y
# CONFIG_RAID_ATTRS is not set
CONFIG_SCSI=y
CONFIG_SCSI_DMA=y
# CONFIG_SCSI_NETLINK is not set
# CONFIG_SCSI_MQ_DEFAULT is not set
CONFIG_SCSI_PROC_FS=y

#
# SCSI support type (disk, tape, CD-ROM)
#
CONFIG_BLK_DEV_SD=y
# CONFIG_CHR_DEV_ST is not set
# CONFIG_CHR_DEV_OSST is not set
# CONFIG_BLK_DEV_SR is not set
# CONFIG_CHR_DEV_SG is not set
# CONFIG_CHR_DEV_SCH is not set
# CONFIG_SCSI_CONSTANTS is not set
# CONFIG_SCSI_LOGGING is not set
# CONFIG_SCSI_SCAN_ASYNC is not set

#
# SCSI Transports
#
# CONFIG_SCSI_SPI_ATTRS is not set
# CONFIG_SCSI_FC_ATTRS is not set
# CONFIG_SCSI_ISCSI_ATTRS is not set
# CONFIG_SCSI_SAS_ATTRS is not set
# CONFIG_SCSI_SAS_LIBSAS is not set
# CONFIG_SCSI_SRP_ATTRS is not set
CONFIG_SCSI_LOWLEVEL=y
# CONFIG_ISCSI_TCP is not set
# CONFIG_ISCSI_BOOT_SYSFS is not set
# CONFIG_SCSI_CXGB3_ISCSI is not set
# CONFIG_SCSI_CXGB4_ISCSI is not set
# CONFIG_SCSI_BNX2_ISCSI is not set
# CONFIG_BE2ISCSI is not set
# CONFIG_BLK_DEV_3W_XXXX_RAID is not set
# CONFIG_SCSI_HPSA is not set
# CONFIG_SCSI_3W_9XXX is not set
# CONFIG_SCSI_3W_SAS is not set
# CONFIG_SCSI_ACARD is not set
# CONFIG_SCSI_AACRAID is not set
# CONFIG_SCSI_AIC7XXX is not set
# CONFIG_SCSI_AIC79XX is not set
# CONFIG_SCSI_AIC94XX is not set
# CONFIG_SCSI_MVSAS is not set
# CONFIG_SCSI_MVUMI is not set
# CONFIG_SCSI_ARCMSR is not set
# CONFIG_SCSI_ESAS2R is not set
# CONFIG_MEGARAID_NEWGEN is not set
# CONFIG_MEGARAID_LEGACY is not set
# CONFIG_MEGARAID_SAS is not set
# CONFIG_SCSI_MPT2SAS is not set
# CONFIG_SCSI_MPT3SAS is not set
# CONFIG_SCSI_UFSHCD is not set
# CONFIG_SCSI_HPTIOP is not set
# CONFIG_XEN_SCSI_FRONTEND is not set
# CONFIG_SCSI_DMX3191D is not set
# CONFIG_SCSI_FUTURE_DOMAIN is not set
# CONFIG_SCSI_IPS is not set
# CONFIG_SCSI_INITIO is not set
# CONFIG_SCSI_INIA100 is not set
# CONFIG_SCSI_STEX is not set
# CONFIG_SCSI_SYM53C8XX_2 is not set
# CONFIG_SCSI_IPR is not set
# CONFIG_SCSI_QLOGIC_1280 is not set
# CONFIG_SCSI_QLA_ISCSI is not set
# CONFIG_SCSI_DC395x is not set
# CONFIG_SCSI_AM53C974 is not set
# CONFIG_SCSI_WD719X is not set
# CONFIG_SCSI_DEBUG is not set
# CONFIG_SCSI_PMCRAID is not set
# CONFIG_SCSI_PM8001 is not set
# CONFIG_SCSI_LOWLEVEL_PCMCIA is not set
# CONFIG_SCSI_DH is not set
# CONFIG_SCSI_OSD_INITIATOR is not set
CONFIG_HAVE_PATA_PLATFORM=y
CONFIG_ATA=y
# CONFIG_ATA_NONSTANDARD is not set
CONFIG_ATA_VERBOSE_ERROR=y
CONFIG_SATA_PMP=y

#
# Controllers with non-SFF native interface
#
# CONFIG_SATA_AHCI is not set
# CONFIG_SATA_AHCI_PLATFORM is not set
# CONFIG_SATA_INIC162X is not set
# CONFIG_SATA_ACARD_AHCI is not set
# CONFIG_SATA_SIL24 is not set
CONFIG_ATA_SFF=y

#
# SFF controllers with custom DMA interface
#
# CONFIG_PDC_ADMA is not set
# CONFIG_SATA_QSTOR is not set
# CONFIG_SATA_SX4 is not set
CONFIG_ATA_BMDMA=y

#
# SATA SFF controllers with BMDMA
#
# CONFIG_ATA_PIIX is not set
# CONFIG_SATA_MV is not set
# CONFIG_SATA_NV is not set
# CONFIG_SATA_PROMISE is not set
# CONFIG_SATA_SIL is not set
# CONFIG_SATA_SIS is not set
# CONFIG_SATA_SVW is not set
# CONFIG_SATA_ULI is not set
# CONFIG_SATA_VIA is not set
# CONFIG_SATA_VITESSE is not set

#
# PATA SFF controllers with BMDMA
#
# CONFIG_PATA_ALI is not set
# CONFIG_PATA_AMD is not set
# CONFIG_PATA_ARTOP is not set
# CONFIG_PATA_ATIIXP is not set
# CONFIG_PATA_ATP867X is not set
# CONFIG_PATA_CMD64X is not set
# CONFIG_PATA_CYPRESS is not set
# CONFIG_PATA_EFAR is not set
# CONFIG_PATA_HPT366 is not set
# CONFIG_PATA_HPT37X is not set
# CONFIG_PATA_HPT3X2N is not set
# CONFIG_PATA_HPT3X3 is not set
# CONFIG_PATA_IT8213 is not set
# CONFIG_PATA_IT821X is not set
# CONFIG_PATA_JMICRON is not set
# CONFIG_PATA_MARVELL is not set
# CONFIG_PATA_NETCELL is not set
# CONFIG_PATA_NINJA32 is not set
# CONFIG_PATA_NS87415 is not set
# CONFIG_PATA_OLDPIIX is not set
# CONFIG_PATA_OPTIDMA is not set
# CONFIG_PATA_PDC2027X is not set
# CONFIG_PATA_PDC_OLD is not set
# CONFIG_PATA_RADISYS is not set
# CONFIG_PATA_RDC is not set
# CONFIG_PATA_SCH is not set
# CONFIG_PATA_SERVERWORKS is not set
# CONFIG_PATA_SIL680 is not set
# CONFIG_PATA_SIS is not set
# CONFIG_PATA_TOSHIBA is not set
# CONFIG_PATA_TRIFLEX is not set
# CONFIG_PATA_VIA is not set
# CONFIG_PATA_WINBOND is not set

#
# PIO-only SFF controllers
#
# CONFIG_PATA_CMD640_PCI is not set
# CONFIG_PATA_MPIIX is not set
# CONFIG_PATA_NS87410 is not set
# CONFIG_PATA_OPTI is not set
# CONFIG_PATA_PLATFORM is not set
# CONFIG_PATA_RZ1000 is not set

#
# Generic fallback / legacy drivers
#
# CONFIG_ATA_GENERIC is not set
# CONFIG_PATA_LEGACY is not set
CONFIG_MD=y
# CONFIG_BLK_DEV_MD is not set
# CONFIG_BCACHE is not set
CONFIG_BLK_DEV_DM_BUILTIN=y
CONFIG_BLK_DEV_DM=y
# CONFIG_DM_DEBUG is not set
CONFIG_DM_BUFIO=y
CONFIG_DM_BIO_PRISON=y
CONFIG_DM_PERSISTENT_DATA=y
# CONFIG_DM_DEBUG_BLOCK_STACK_TRACING is not set
# CONFIG_DM_CRYPT is not set
CONFIG_DM_SNAPSHOT=y
CONFIG_DM_THIN_PROVISIONING=y
# CONFIG_DM_CACHE is not set
# CONFIG_DM_ERA is not set
# CONFIG_DM_MIRROR is not set
# CONFIG_DM_RAID is not set
# CONFIG_DM_ZERO is not set
CONFIG_DM_MULTIPATH=y
# CONFIG_DM_MULTIPATH_QL is not set
# CONFIG_DM_MULTIPATH_ST is not set
# CONFIG_DM_DELAY is not set
CONFIG_DM_UEVENT=y
# CONFIG_DM_FLAKEY is not set
# CONFIG_DM_VERITY is not set
# CONFIG_DM_SWITCH is not set
# CONFIG_TARGET_CORE is not set
# CONFIG_FUSION is not set

#
# IEEE 1394 (FireWire) support
#
# CONFIG_FIREWIRE is not set
# CONFIG_FIREWIRE_NOSY is not set
# CONFIG_I2O is not set
CONFIG_NETDEVICES=y
CONFIG_MII=y
CONFIG_NET_CORE=y
# CONFIG_BONDING is not set
# CONFIG_DUMMY is not set
# CONFIG_EQUALIZER is not set
# CONFIG_NET_FC is not set
# CONFIG_NET_TEAM is not set
# CONFIG_MACVLAN is not set
# CONFIG_VXLAN is not set
# CONFIG_NETCONSOLE is not set
# CONFIG_NETPOLL is not set
# CONFIG_NET_POLL_CONTROLLER is not set
CONFIG_TUN=y
# CONFIG_VETH is not set
# CONFIG_NLMON is not set
# CONFIG_ARCNET is not set

#
# CAIF transport drivers
#

#
# Distributed Switch Architecture drivers
#
# CONFIG_NET_DSA_MV88E6XXX is not set
# CONFIG_NET_DSA_MV88E6060 is not set
# CONFIG_NET_DSA_MV88E6XXX_NEED_PPU is not set
# CONFIG_NET_DSA_MV88E6131 is not set
# CONFIG_NET_DSA_MV88E6123_61_65 is not set
# CONFIG_NET_DSA_MV88E6171 is not set
# CONFIG_NET_DSA_MV88E6352 is not set
# CONFIG_NET_DSA_BCM_SF2 is not set
CONFIG_ETHERNET=y
CONFIG_NET_VENDOR_3COM=y
# CONFIG_VORTEX is not set
# CONFIG_TYPHOON is not set
CONFIG_NET_VENDOR_ADAPTEC=y
# CONFIG_ADAPTEC_STARFIRE is not set
CONFIG_NET_VENDOR_AGERE=y
# CONFIG_ET131X is not set
CONFIG_NET_VENDOR_ALTEON=y
# CONFIG_ACENIC is not set
# CONFIG_ALTERA_TSE is not set
CONFIG_NET_VENDOR_AMD=y
# CONFIG_AMD8111_ETH is not set
# CONFIG_PCNET32 is not set
# CONFIG_AMD_XGBE is not set
# CONFIG_NET_XGENE is not set
CONFIG_NET_VENDOR_ARC=y
# CONFIG_ARC_EMAC is not set
CONFIG_NET_VENDOR_ATHEROS=y
# CONFIG_ATL2 is not set
# CONFIG_ATL1 is not set
# CONFIG_ATL1E is not set
# CONFIG_ATL1C is not set
# CONFIG_ALX is not set
CONFIG_NET_VENDOR_BROADCOM=y
# CONFIG_B44 is not set
# CONFIG_BCMGENET is not set
# CONFIG_BNX2 is not set
# CONFIG_CNIC is not set
# CONFIG_TIGON3 is not set
# CONFIG_BNX2X is not set
# CONFIG_SYSTEMPORT is not set
CONFIG_NET_VENDOR_BROCADE=y
# CONFIG_BNA is not set
CONFIG_NET_VENDOR_CHELSIO=y
# CONFIG_CHELSIO_T1 is not set
# CONFIG_CHELSIO_T3 is not set
# CONFIG_CHELSIO_T4 is not set
# CONFIG_CHELSIO_T4VF is not set
CONFIG_NET_VENDOR_CISCO=y
# CONFIG_ENIC is not set
# CONFIG_DNET is not set
CONFIG_NET_VENDOR_DEC=y
# CONFIG_NET_TULIP is not set
CONFIG_NET_VENDOR_DLINK=y
# CONFIG_DL2K is not set
# CONFIG_SUNDANCE is not set
CONFIG_NET_VENDOR_EMULEX=y
# CONFIG_BE2NET is not set
CONFIG_NET_VENDOR_EXAR=y
# CONFIG_S2IO is not set
# CONFIG_VXGE is not set
CONFIG_NET_VENDOR_HP=y
# CONFIG_HP100 is not set
CONFIG_NET_VENDOR_INTEL=y
# CONFIG_E100 is not set
# CONFIG_E1000 is not set
# CONFIG_E1000E is not set
# CONFIG_IGB is not set
# CONFIG_IGBVF is not set
# CONFIG_IXGB is not set
# CONFIG_IXGBE is not set
# CONFIG_IXGBEVF is not set
# CONFIG_I40E is not set
# CONFIG_I40EVF is not set
# CONFIG_FM10K is not set
CONFIG_NET_VENDOR_I825XX=y
# CONFIG_IP1000 is not set
# CONFIG_JME is not set
CONFIG_NET_VENDOR_MARVELL=y
# CONFIG_MVMDIO is not set
# CONFIG_SKGE is not set
# CONFIG_SKY2 is not set
CONFIG_NET_VENDOR_MELLANOX=y
# CONFIG_MLX4_EN is not set
# CONFIG_MLX4_CORE is not set
# CONFIG_MLX5_CORE is not set
CONFIG_NET_VENDOR_MICREL=y
# CONFIG_KS8851_MLL is not set
# CONFIG_KSZ884X_PCI is not set
CONFIG_NET_VENDOR_MYRI=y
# CONFIG_MYRI10GE is not set
# CONFIG_FEALNX is not set
CONFIG_NET_VENDOR_NATSEMI=y
# CONFIG_NATSEMI is not set
# CONFIG_NS83820 is not set
CONFIG_NET_VENDOR_8390=y
# CONFIG_NE2K_PCI is not set
CONFIG_NET_VENDOR_NVIDIA=y
# CONFIG_FORCEDETH is not set
CONFIG_NET_VENDOR_OKI=y
# CONFIG_ETHOC is not set
CONFIG_NET_PACKET_ENGINE=y
# CONFIG_HAMACHI is not set
# CONFIG_YELLOWFIN is not set
CONFIG_NET_VENDOR_QLOGIC=y
# CONFIG_QLA3XXX is not set
# CONFIG_QLCNIC is not set
# CONFIG_QLGE is not set
# CONFIG_NETXEN_NIC is not set
CONFIG_NET_VENDOR_QUALCOMM=y
CONFIG_NET_VENDOR_REALTEK=y
# CONFIG_8139CP is not set
# CONFIG_8139TOO is not set
# CONFIG_R8169 is not set
CONFIG_NET_VENDOR_RDC=y
# CONFIG_R6040 is not set
CONFIG_NET_VENDOR_ROCKER=y
CONFIG_NET_VENDOR_SAMSUNG=y
# CONFIG_SXGBE_ETH is not set
CONFIG_NET_VENDOR_SEEQ=y
CONFIG_NET_VENDOR_SILAN=y
# CONFIG_SC92031 is not set
CONFIG_NET_VENDOR_SIS=y
# CONFIG_SIS900 is not set
# CONFIG_SIS190 is not set
# CONFIG_SFC is not set
CONFIG_NET_VENDOR_SMSC=y
# CONFIG_SMC91X is not set
# CONFIG_EPIC100 is not set
CONFIG_SMSC911X=y
# CONFIG_SMSC911X_ARCH_HOOKS is not set
# CONFIG_SMSC9420 is not set
CONFIG_NET_VENDOR_STMICRO=y
# CONFIG_STMMAC_ETH is not set
CONFIG_NET_VENDOR_SUN=y
# CONFIG_HAPPYMEAL is not set
# CONFIG_SUNGEM is not set
# CONFIG_CASSINI is not set
# CONFIG_NIU is not set
CONFIG_NET_VENDOR_TEHUTI=y
# CONFIG_TEHUTI is not set
CONFIG_NET_VENDOR_TI=y
# CONFIG_TLAN is not set
CONFIG_NET_VENDOR_VIA=y
# CONFIG_VIA_RHINE is not set
# CONFIG_VIA_VELOCITY is not set
CONFIG_NET_VENDOR_WIZNET=y
# CONFIG_WIZNET_W5100 is not set
# CONFIG_WIZNET_W5300 is not set
# CONFIG_FDDI is not set
# CONFIG_HIPPI is not set
CONFIG_PHYLIB=y

#
# MII PHY device drivers
#
# CONFIG_AT803X_PHY is not set
# CONFIG_AMD_PHY is not set
# CONFIG_AMD_XGBE_PHY is not set
# CONFIG_MARVELL_PHY is not set
# CONFIG_DAVICOM_PHY is not set
# CONFIG_QSEMI_PHY is not set
# CONFIG_LXT_PHY is not set
# CONFIG_CICADA_PHY is not set
# CONFIG_VITESSE_PHY is not set
CONFIG_SMSC_PHY=y
# CONFIG_BROADCOM_PHY is not set
# CONFIG_BCM7XXX_PHY is not set
# CONFIG_BCM87XX_PHY is not set
# CONFIG_ICPLUS_PHY is not set
# CONFIG_REALTEK_PHY is not set
# CONFIG_NATIONAL_PHY is not set
# CONFIG_STE10XP is not set
# CONFIG_LSI_ET1011C_PHY is not set
# CONFIG_MICREL_PHY is not set
# CONFIG_FIXED_PHY is not set
# CONFIG_MDIO_BITBANG is not set
# CONFIG_MDIO_BUS_MUX_GPIO is not set
# CONFIG_MDIO_BUS_MUX_MMIOREG is not set
# CONFIG_MDIO_BCM_UNIMAC is not set
# CONFIG_PPP is not set
# CONFIG_SLIP is not set
CONFIG_USB_NET_DRIVERS=y
# CONFIG_USB_CATC is not set
# CONFIG_USB_KAWETH is not set
# CONFIG_USB_PEGASUS is not set
# CONFIG_USB_RTL8150 is not set
# CONFIG_USB_RTL8152 is not set
# CONFIG_USB_USBNET is not set
# CONFIG_USB_IPHETH is not set
CONFIG_WLAN=y
# CONFIG_PRISM54 is not set
# CONFIG_HOSTAP is not set
# CONFIG_WL_TI is not set

#
# Enable WiMAX (Networking options) to see the WiMAX drivers
#
# CONFIG_WAN is not set
CONFIG_XEN_NETDEV_FRONTEND=y
CONFIG_XEN_NETDEV_BACKEND=y
# CONFIG_VMXNET3 is not set
# CONFIG_ISDN is not set

#
# Input device support
#
CONFIG_INPUT=y
# CONFIG_INPUT_FF_MEMLESS is not set
# CONFIG_INPUT_POLLDEV is not set
# CONFIG_INPUT_SPARSEKMAP is not set
# CONFIG_INPUT_MATRIXKMAP is not set

#
# Userland interfaces
#
CONFIG_INPUT_MOUSEDEV=y
CONFIG_INPUT_MOUSEDEV_PSAUX=y
CONFIG_INPUT_MOUSEDEV_SCREEN_X=1024
CONFIG_INPUT_MOUSEDEV_SCREEN_Y=768
# CONFIG_INPUT_JOYDEV is not set
CONFIG_INPUT_EVDEV=y
# CONFIG_INPUT_EVBUG is not set

#
# Input Device Drivers
#
CONFIG_INPUT_KEYBOARD=y
# CONFIG_KEYBOARD_ADP5588 is not set
# CONFIG_KEYBOARD_ADP5589 is not set
CONFIG_KEYBOARD_ATKBD=y
# CONFIG_KEYBOARD_QT1070 is not set
# CONFIG_KEYBOARD_QT2160 is not set
# CONFIG_KEYBOARD_LKKBD is not set
# CONFIG_KEYBOARD_GPIO is not set
# CONFIG_KEYBOARD_GPIO_POLLED is not set
# CONFIG_KEYBOARD_TCA6416 is not set
# CONFIG_KEYBOARD_TCA8418 is not set
# CONFIG_KEYBOARD_MATRIX is not set
# CONFIG_KEYBOARD_LM8333 is not set
# CONFIG_KEYBOARD_MAX7359 is not set
# CONFIG_KEYBOARD_MCS is not set
# CONFIG_KEYBOARD_MPR121 is not set
# CONFIG_KEYBOARD_NEWTON is not set
# CONFIG_KEYBOARD_OPENCORES is not set
# CONFIG_KEYBOARD_SAMSUNG is not set
# CONFIG_KEYBOARD_STOWAWAY is not set
# CONFIG_KEYBOARD_SUNKBD is not set
# CONFIG_KEYBOARD_OMAP4 is not set
# CONFIG_KEYBOARD_XTKBD is not set
# CONFIG_KEYBOARD_CAP11XX is not set
CONFIG_INPUT_MOUSE=y
CONFIG_MOUSE_PS2=y
CONFIG_MOUSE_PS2_ALPS=y
CONFIG_MOUSE_PS2_LOGIPS2PP=y
CONFIG_MOUSE_PS2_SYNAPTICS=y
CONFIG_MOUSE_PS2_CYPRESS=y
CONFIG_MOUSE_PS2_TRACKPOINT=y
# CONFIG_MOUSE_PS2_ELANTECH is not set
# CONFIG_MOUSE_PS2_SENTELIC is not set
# CONFIG_MOUSE_PS2_TOUCHKIT is not set
# CONFIG_MOUSE_SERIAL is not set
# CONFIG_MOUSE_APPLETOUCH is not set
# CONFIG_MOUSE_BCM5974 is not set
# CONFIG_MOUSE_CYAPA is not set
# CONFIG_MOUSE_ELAN_I2C is not set
# CONFIG_MOUSE_VSXXXAA is not set
# CONFIG_MOUSE_GPIO is not set
# CONFIG_MOUSE_SYNAPTICS_I2C is not set
# CONFIG_MOUSE_SYNAPTICS_USB is not set
# CONFIG_INPUT_JOYSTICK is not set
# CONFIG_INPUT_TABLET is not set
# CONFIG_INPUT_TOUCHSCREEN is not set
# CONFIG_INPUT_MISC is not set

#
# Hardware I/O ports
#
CONFIG_SERIO=y
# CONFIG_SERIO_SERPORT is not set
CONFIG_SERIO_AMBAKMI=y
# CONFIG_SERIO_PCIPS2 is not set
CONFIG_SERIO_LIBPS2=y
# CONFIG_SERIO_RAW is not set
# CONFIG_SERIO_ALTERA_PS2 is not set
# CONFIG_SERIO_PS2MULT is not set
# CONFIG_SERIO_ARC_PS2 is not set
# CONFIG_SERIO_APBPS2 is not set
# CONFIG_GAMEPORT is not set

#
# Character devices
#
CONFIG_TTY=y
CONFIG_VT=y
CONFIG_CONSOLE_TRANSLATIONS=y
CONFIG_VT_CONSOLE=y
CONFIG_VT_CONSOLE_SLEEP=y
CONFIG_HW_CONSOLE=y
CONFIG_VT_HW_CONSOLE_BINDING=y
CONFIG_UNIX98_PTYS=y
# CONFIG_DEVPTS_MULTIPLE_INSTANCES is not set
CONFIG_LEGACY_PTYS=y
CONFIG_LEGACY_PTY_COUNT=16
# CONFIG_SERIAL_NONSTANDARD is not set
# CONFIG_NOZOMI is not set
# CONFIG_N_GSM is not set
# CONFIG_TRACE_SINK is not set
CONFIG_DEVKMEM=y

#
# Serial drivers
#
CONFIG_SERIAL_EARLYCON=y
CONFIG_SERIAL_8250=y
CONFIG_SERIAL_8250_DEPRECATED_OPTIONS=y
# CONFIG_SERIAL_8250_CONSOLE is not set
CONFIG_SERIAL_8250_PCI=y
CONFIG_SERIAL_8250_NR_UARTS=4
CONFIG_SERIAL_8250_RUNTIME_UARTS=4
CONFIG_SERIAL_8250_EXTENDED=y
CONFIG_SERIAL_8250_MANY_PORTS=y
CONFIG_SERIAL_8250_SHARE_IRQ=y
# CONFIG_SERIAL_8250_DETECT_IRQ is not set
CONFIG_SERIAL_8250_RSA=y
# CONFIG_SERIAL_8250_DW is not set

#
# Non-8250 serial port support
#
# CONFIG_SERIAL_AMBA_PL010 is not set
CONFIG_SERIAL_AMBA_PL011=y
CONFIG_SERIAL_AMBA_PL011_CONSOLE=y
# CONFIG_SERIAL_EARLYCON_ARM_SEMIHOST is not set
# CONFIG_SERIAL_MFD_HSU is not set
CONFIG_SERIAL_CORE=y
CONFIG_SERIAL_CORE_CONSOLE=y
# CONFIG_SERIAL_JSM is not set
# CONFIG_SERIAL_OF_PLATFORM is not set
# CONFIG_SERIAL_SCCNXP is not set
# CONFIG_SERIAL_SC16IS7XX is not set
# CONFIG_SERIAL_ALTERA_JTAGUART is not set
# CONFIG_SERIAL_ALTERA_UART is not set
# CONFIG_SERIAL_XILINX_PS_UART is not set
# CONFIG_SERIAL_ARC is not set
# CONFIG_SERIAL_RP2 is not set
# CONFIG_SERIAL_FSL_LPUART is not set
# CONFIG_TTY_PRINTK is not set
CONFIG_HVC_DRIVER=y
CONFIG_HVC_IRQ=y
CONFIG_HVC_XEN=y
# CONFIG_HVC_XEN_FRONTEND is not set
# CONFIG_IPMI_HANDLER is not set
CONFIG_HW_RANDOM=y
# CONFIG_HW_RANDOM_TIMERIOMEM is not set
CONFIG_HW_RANDOM_XGENE=y
# CONFIG_R3964 is not set
# CONFIG_APPLICOM is not set

#
# PCMCIA character devices
#
# CONFIG_RAW_DRIVER is not set
# CONFIG_TCG_TPM is not set
CONFIG_DEVPORT=y
# CONFIG_XILLYBUS is not set

#
# I2C support
#
CONFIG_I2C=y
CONFIG_I2C_BOARDINFO=y
CONFIG_I2C_COMPAT=y
CONFIG_I2C_CHARDEV=y
# CONFIG_I2C_MUX is not set
CONFIG_I2C_HELPER_AUTO=y

#
# I2C Hardware Bus support
#

#
# PC SMBus host controller drivers
#
# CONFIG_I2C_ALI1535 is not set
# CONFIG_I2C_ALI1563 is not set
# CONFIG_I2C_ALI15X3 is not set
# CONFIG_I2C_AMD756 is not set
# CONFIG_I2C_AMD8111 is not set
# CONFIG_I2C_I801 is not set
# CONFIG_I2C_ISCH is not set
# CONFIG_I2C_PIIX4 is not set
# CONFIG_I2C_NFORCE2 is not set
# CONFIG_I2C_SIS5595 is not set
# CONFIG_I2C_SIS630 is not set
# CONFIG_I2C_SIS96X is not set
# CONFIG_I2C_VIA is not set
# CONFIG_I2C_VIAPRO is not set

#
# I2C system bus drivers (mostly embedded / system-on-chip)
#
# CONFIG_I2C_CBUS_GPIO is not set
# CONFIG_I2C_DESIGNWARE_PLATFORM is not set
# CONFIG_I2C_DESIGNWARE_PCI is not set
# CONFIG_I2C_GPIO is not set
# CONFIG_I2C_NOMADIK is not set
# CONFIG_I2C_OCORES is not set
# CONFIG_I2C_PCA_PLATFORM is not set
# CONFIG_I2C_PXA_PCI is not set
# CONFIG_I2C_RK3X is not set
# CONFIG_I2C_SIMTEC is not set
# CONFIG_I2C_VERSATILE is not set
# CONFIG_I2C_XILINX is not set

#
# External I2C/SMBus adapter drivers
#
# CONFIG_I2C_DIOLAN_U2C is not set
# CONFIG_I2C_PARPORT_LIGHT is not set
# CONFIG_I2C_ROBOTFUZZ_OSIF is not set
# CONFIG_I2C_TAOS_EVM is not set
# CONFIG_I2C_TINY_USB is not set

#
# Other I2C/SMBus bus drivers
#
# CONFIG_I2C_SLAVE is not set
# CONFIG_I2C_DEBUG_CORE is not set
# CONFIG_I2C_DEBUG_ALGO is not set
# CONFIG_I2C_DEBUG_BUS is not set
# CONFIG_SPI is not set
# CONFIG_SPMI is not set
# CONFIG_HSI is not set

#
# PPS support
#
# CONFIG_PPS is not set

#
# PPS generators support
#

#
# PTP clock support
#
# CONFIG_PTP_1588_CLOCK is not set

#
# Enable PHYLIB and NETWORK_PHY_TIMESTAMPING to see the additional clocks.
#
CONFIG_ARCH_WANT_OPTIONAL_GPIOLIB=y
CONFIG_ARCH_REQUIRE_GPIOLIB=y
CONFIG_GPIOLIB=y
CONFIG_GPIO_DEVRES=y
CONFIG_OF_GPIO=y
# CONFIG_DEBUG_GPIO is not set
# CONFIG_GPIO_SYSFS is not set
CONFIG_GPIO_GENERIC=y

#
# Memory mapped GPIO drivers:
#
# CONFIG_GPIO_74XX_MMIO is not set
CONFIG_GPIO_GENERIC_PLATFORM=y
# CONFIG_GPIO_PL061 is not set
# CONFIG_GPIO_SCH311X is not set
# CONFIG_GPIO_SYSCON is not set
# CONFIG_GPIO_XGENE is not set
# CONFIG_GPIO_VX855 is not set
# CONFIG_GPIO_GRGPIO is not set

#
# I2C GPIO expanders:
#
# CONFIG_GPIO_MAX7300 is not set
# CONFIG_GPIO_MAX732X is not set
# CONFIG_GPIO_PCA953X is not set
# CONFIG_GPIO_PCF857X is not set
# CONFIG_GPIO_SX150X is not set
# CONFIG_GPIO_ADP5588 is not set
# CONFIG_GPIO_ADNP is not set

#
# PCI GPIO expanders:
#
# CONFIG_GPIO_BT8XX is not set
# CONFIG_GPIO_AMD8111 is not set
# CONFIG_GPIO_ML_IOH is not set
# CONFIG_GPIO_RDC321X is not set

#
# SPI GPIO expanders:
#
# CONFIG_GPIO_MCP23S08 is not set

#
# AC97 GPIO expanders:
#

#
# LPC GPIO expanders:
#

#
# MODULbus GPIO expanders:
#

#
# USB GPIO expanders:
#
# CONFIG_W1 is not set
CONFIG_POWER_SUPPLY=y
# CONFIG_POWER_SUPPLY_DEBUG is not set
# CONFIG_PDA_POWER is not set
# CONFIG_TEST_POWER is not set
# CONFIG_BATTERY_DS2780 is not set
# CONFIG_BATTERY_DS2781 is not set
# CONFIG_BATTERY_DS2782 is not set
# CONFIG_BATTERY_SBS is not set
# CONFIG_BATTERY_BQ27x00 is not set
# CONFIG_BATTERY_MAX17040 is not set
# CONFIG_BATTERY_MAX17042 is not set
# CONFIG_CHARGER_MAX8903 is not set
# CONFIG_CHARGER_LP8727 is not set
# CONFIG_CHARGER_GPIO is not set
# CONFIG_CHARGER_BQ2415X is not set
# CONFIG_CHARGER_BQ24190 is not set
# CONFIG_CHARGER_BQ24735 is not set
# CONFIG_CHARGER_SMB347 is not set
CONFIG_POWER_RESET=y
# CONFIG_POWER_RESET_GPIO is not set
# CONFIG_POWER_RESET_GPIO_RESTART is not set
# CONFIG_POWER_RESET_LTC2952 is not set
CONFIG_POWER_RESET_VEXPRESS=y
# CONFIG_POWER_RESET_XGENE is not set
# CONFIG_POWER_RESET_SYSCON is not set
# CONFIG_POWER_AVS is not set
# CONFIG_HWMON is not set
# CONFIG_THERMAL is not set
# CONFIG_WATCHDOG is not set
CONFIG_SSB_POSSIBLE=y

#
# Sonics Silicon Backplane
#
# CONFIG_SSB is not set
CONFIG_BCMA_POSSIBLE=y

#
# Broadcom specific AMBA
#
# CONFIG_BCMA is not set

#
# Multifunction device drivers
#
CONFIG_MFD_CORE=y
# CONFIG_MFD_AS3711 is not set
# CONFIG_MFD_AS3722 is not set
# CONFIG_PMIC_ADP5520 is not set
# CONFIG_MFD_AAT2870_CORE is not set
# CONFIG_MFD_ATMEL_HLCDC is not set
# CONFIG_MFD_BCM590XX is not set
# CONFIG_MFD_AXP20X is not set
# CONFIG_MFD_CROS_EC is not set
# CONFIG_PMIC_DA903X is not set
# CONFIG_MFD_DA9052_I2C is not set
# CONFIG_MFD_DA9055 is not set
# CONFIG_MFD_DA9063 is not set
# CONFIG_MFD_DLN2 is not set
# CONFIG_MFD_MC13XXX_I2C is not set
# CONFIG_MFD_HI6421_PMIC is not set
# CONFIG_HTC_PASIC3 is not set
# CONFIG_HTC_I2CPLD is not set
# CONFIG_LPC_ICH is not set
# CONFIG_LPC_SCH is not set
# CONFIG_INTEL_SOC_PMIC is not set
# CONFIG_MFD_JANZ_CMODIO is not set
# CONFIG_MFD_KEMPLD is not set
# CONFIG_MFD_88PM800 is not set
# CONFIG_MFD_88PM805 is not set
# CONFIG_MFD_88PM860X is not set
# CONFIG_MFD_MAX14577 is not set
# CONFIG_MFD_MAX77686 is not set
# CONFIG_MFD_MAX77693 is not set
# CONFIG_MFD_MAX8907 is not set
# CONFIG_MFD_MAX8925 is not set
# CONFIG_MFD_MAX8997 is not set
# CONFIG_MFD_MAX8998 is not set
# CONFIG_MFD_MENF21BMC is not set
# CONFIG_MFD_VIPERBOARD is not set
# CONFIG_MFD_RETU is not set
# CONFIG_MFD_PCF50633 is not set
# CONFIG_MFD_RDC321X is not set
# CONFIG_MFD_RTSX_PCI is not set
# CONFIG_MFD_RTSX_USB is not set
# CONFIG_MFD_RC5T583 is not set
# CONFIG_MFD_RK808 is not set
# CONFIG_MFD_RN5T618 is not set
# CONFIG_MFD_SEC_CORE is not set
# CONFIG_MFD_SI476X_CORE is not set
# CONFIG_MFD_SM501 is not set
# CONFIG_MFD_SMSC is not set
# CONFIG_ABX500_CORE is not set
# CONFIG_MFD_STMPE is not set
CONFIG_MFD_SYSCON=y
# CONFIG_MFD_TI_AM335X_TSCADC is not set
# CONFIG_MFD_LP3943 is not set
# CONFIG_MFD_LP8788 is not set
# CONFIG_MFD_PALMAS is not set
# CONFIG_TPS6105X is not set
# CONFIG_TPS65010 is not set
# CONFIG_TPS6507X is not set
# CONFIG_MFD_TPS65090 is not set
# CONFIG_MFD_TPS65217 is not set
# CONFIG_MFD_TPS65218 is not set
# CONFIG_MFD_TPS6586X is not set
# CONFIG_MFD_TPS65910 is not set
# CONFIG_MFD_TPS65912 is not set
# CONFIG_MFD_TPS65912_I2C is not set
# CONFIG_MFD_TPS80031 is not set
# CONFIG_TWL4030_CORE is not set
# CONFIG_TWL6040_CORE is not set
# CONFIG_MFD_WL1273_CORE is not set
# CONFIG_MFD_LM3533 is not set
# CONFIG_MFD_TC3589X is not set
# CONFIG_MFD_TMIO is not set
# CONFIG_MFD_VX855 is not set
# CONFIG_MFD_ARIZONA_I2C is not set
# CONFIG_MFD_WM8400 is not set
# CONFIG_MFD_WM831X_I2C is not set
# CONFIG_MFD_WM8350_I2C is not set
# CONFIG_MFD_WM8994 is not set
CONFIG_MFD_VEXPRESS_SYSREG=y
# CONFIG_REGULATOR is not set
# CONFIG_MEDIA_SUPPORT is not set

#
# Graphics support
#
CONFIG_VGA_ARB=y
CONFIG_VGA_ARB_MAX_GPUS=16

#
# Direct Rendering Manager
#
# CONFIG_DRM is not set

#
# Frame buffer Devices
#
CONFIG_FB=y
# CONFIG_FIRMWARE_EDID is not set
CONFIG_FB_CMDLINE=y
# CONFIG_FB_DDC is not set
# CONFIG_FB_BOOT_VESA_SUPPORT is not set
CONFIG_FB_CFB_FILLRECT=y
CONFIG_FB_CFB_COPYAREA=y
CONFIG_FB_CFB_IMAGEBLIT=y
# CONFIG_FB_CFB_REV_PIXELS_IN_BYTE is not set
# CONFIG_FB_SYS_FILLRECT is not set
# CONFIG_FB_SYS_COPYAREA is not set
# CONFIG_FB_SYS_IMAGEBLIT is not set
# CONFIG_FB_FOREIGN_ENDIAN is not set
# CONFIG_FB_SYS_FOPS is not set
# CONFIG_FB_SVGALIB is not set
# CONFIG_FB_MACMODES is not set
# CONFIG_FB_BACKLIGHT is not set
CONFIG_FB_MODE_HELPERS=y
# CONFIG_FB_TILEBLITTING is not set

#
# Frame buffer hardware drivers
#
# CONFIG_FB_CIRRUS is not set
# CONFIG_FB_PM2 is not set
CONFIG_FB_ARMCLCD=y
# CONFIG_FB_CYBER2000 is not set
# CONFIG_FB_ASILIANT is not set
# CONFIG_FB_IMSTT is not set
# CONFIG_FB_OPENCORES is not set
# CONFIG_FB_S1D13XXX is not set
# CONFIG_FB_NVIDIA is not set
# CONFIG_FB_RIVA is not set
# CONFIG_FB_I740 is not set
# CONFIG_FB_MATROX is not set
# CONFIG_FB_RADEON is not set
# CONFIG_FB_ATY128 is not set
# CONFIG_FB_ATY is not set
# CONFIG_FB_S3 is not set
# CONFIG_FB_SAVAGE is not set
# CONFIG_FB_SIS is not set
# CONFIG_FB_NEOMAGIC is not set
# CONFIG_FB_KYRO is not set
# CONFIG_FB_3DFX is not set
# CONFIG_FB_VOODOO1 is not set
# CONFIG_FB_VT8623 is not set
# CONFIG_FB_TRIDENT is not set
# CONFIG_FB_ARK is not set
# CONFIG_FB_PM3 is not set
# CONFIG_FB_CARMINE is not set
# CONFIG_FB_SMSCUFX is not set
# CONFIG_FB_UDL is not set
# CONFIG_FB_VIRTUAL is not set
# CONFIG_XEN_FBDEV_FRONTEND is not set
# CONFIG_FB_METRONOME is not set
# CONFIG_FB_MB862XX is not set
# CONFIG_FB_BROADSHEET is not set
# CONFIG_FB_AUO_K190X is not set
# CONFIG_FB_SIMPLE is not set
# CONFIG_FB_SSD1307 is not set
# CONFIG_BACKLIGHT_LCD_SUPPORT is not set
# CONFIG_VGASTATE is not set
CONFIG_VIDEOMODE_HELPERS=y

#
# Console display driver support
#
CONFIG_DUMMY_CONSOLE=y
CONFIG_FRAMEBUFFER_CONSOLE=y
# CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY is not set
# CONFIG_FRAMEBUFFER_CONSOLE_ROTATION is not set
# CONFIG_LOGO is not set
CONFIG_SOUND=y
CONFIG_SOUND_OSS_CORE=y
CONFIG_SOUND_OSS_CORE_PRECLAIM=y
CONFIG_SND=y
CONFIG_SND_TIMER=y
CONFIG_SND_PCM=y
# CONFIG_SND_SEQUENCER is not set
CONFIG_SND_OSSEMUL=y
CONFIG_SND_MIXER_OSS=y
CONFIG_SND_PCM_OSS=y
CONFIG_SND_PCM_OSS_PLUGINS=y
# CONFIG_SND_HRTIMER is not set
# CONFIG_SND_DYNAMIC_MINORS is not set
CONFIG_SND_SUPPORT_OLD_API=y
CONFIG_SND_VERBOSE_PROCFS=y
# CONFIG_SND_VERBOSE_PRINTK is not set
# CONFIG_SND_DEBUG is not set
# CONFIG_SND_RAWMIDI_SEQ is not set
# CONFIG_SND_OPL3_LIB_SEQ is not set
# CONFIG_SND_OPL4_LIB_SEQ is not set
# CONFIG_SND_SBAWE_SEQ is not set
# CONFIG_SND_EMU10K1_SEQ is not set
CONFIG_SND_DRIVERS=y
# CONFIG_SND_DUMMY is not set
# CONFIG_SND_ALOOP is not set
# CONFIG_SND_MTPAV is not set
# CONFIG_SND_SERIAL_U16550 is not set
# CONFIG_SND_MPU401 is not set
CONFIG_SND_PCI=y
# CONFIG_SND_AD1889 is not set
# CONFIG_SND_ALS300 is not set
# CONFIG_SND_ALI5451 is not set
# CONFIG_SND_ATIIXP is not set
# CONFIG_SND_ATIIXP_MODEM is not set
# CONFIG_SND_AU8810 is not set
# CONFIG_SND_AU8820 is not set
# CONFIG_SND_AU8830 is not set
# CONFIG_SND_AW2 is not set
# CONFIG_SND_AZT3328 is not set
# CONFIG_SND_BT87X is not set
# CONFIG_SND_CA0106 is not set
# CONFIG_SND_CMIPCI is not set
# CONFIG_SND_OXYGEN is not set
# CONFIG_SND_CS4281 is not set
# CONFIG_SND_CS46XX is not set
# CONFIG_SND_CTXFI is not set
# CONFIG_SND_DARLA20 is not set
# CONFIG_SND_GINA20 is not set
# CONFIG_SND_LAYLA20 is not set
# CONFIG_SND_DARLA24 is not set
# CONFIG_SND_GINA24 is not set
# CONFIG_SND_LAYLA24 is not set
# CONFIG_SND_MONA is not set
# CONFIG_SND_MIA is not set
# CONFIG_SND_ECHO3G is not set
# CONFIG_SND_INDIGO is not set
# CONFIG_SND_INDIGOIO is not set
# CONFIG_SND_INDIGODJ is not set
# CONFIG_SND_INDIGOIOX is not set
# CONFIG_SND_INDIGODJX is not set
# CONFIG_SND_EMU10K1 is not set
# CONFIG_SND_EMU10K1X is not set
# CONFIG_SND_ENS1370 is not set
# CONFIG_SND_ENS1371 is not set
# CONFIG_SND_ES1938 is not set
# CONFIG_SND_ES1968 is not set
# CONFIG_SND_FM801 is not set
# CONFIG_SND_HDSP is not set
# CONFIG_SND_HDSPM is not set
# CONFIG_SND_ICE1712 is not set
# CONFIG_SND_ICE1724 is not set
# CONFIG_SND_INTEL8X0 is not set
# CONFIG_SND_INTEL8X0M is not set
# CONFIG_SND_KORG1212 is not set
# CONFIG_SND_LOLA is not set
# CONFIG_SND_LX6464ES is not set
# CONFIG_SND_MAESTRO3 is not set
# CONFIG_SND_MIXART is not set
# CONFIG_SND_NM256 is not set
# CONFIG_SND_PCXHR is not set
# CONFIG_SND_RIPTIDE is not set
# CONFIG_SND_RME32 is not set
# CONFIG_SND_RME96 is not set
# CONFIG_SND_RME9652 is not set
# CONFIG_SND_SONICVIBES is not set
# CONFIG_SND_TRIDENT is not set
# CONFIG_SND_VIA82XX is not set
# CONFIG_SND_VIA82XX_MODEM is not set
# CONFIG_SND_VIRTUOSO is not set
# CONFIG_SND_VX222 is not set
# CONFIG_SND_YMFPCI is not set

#
# HD-Audio
#
# CONFIG_SND_HDA_INTEL is not set
CONFIG_SND_USB=y
# CONFIG_SND_USB_AUDIO is not set
# CONFIG_SND_USB_UA101 is not set
# CONFIG_SND_USB_CAIAQ is not set
# CONFIG_SND_USB_6FIRE is not set
# CONFIG_SND_USB_HIFACE is not set
# CONFIG_SND_BCD2000 is not set
# CONFIG_SND_SOC is not set
# CONFIG_SOUND_PRIME is not set

#
# HID support
#
CONFIG_HID=y
# CONFIG_HID_BATTERY_STRENGTH is not set
# CONFIG_HIDRAW is not set
# CONFIG_UHID is not set
CONFIG_HID_GENERIC=y

#
# Special HID drivers
#
# CONFIG_HID_A4TECH is not set
# CONFIG_HID_ACRUX is not set
# CONFIG_HID_APPLE is not set
# CONFIG_HID_APPLEIR is not set
# CONFIG_HID_AUREAL is not set
# CONFIG_HID_BELKIN is not set
# CONFIG_HID_CHERRY is not set
# CONFIG_HID_CHICONY is not set
# CONFIG_HID_PRODIKEYS is not set
# CONFIG_HID_CP2112 is not set
# CONFIG_HID_CYPRESS is not set
# CONFIG_HID_DRAGONRISE is not set
# CONFIG_HID_EMS_FF is not set
# CONFIG_HID_ELECOM is not set
# CONFIG_HID_ELO is not set
# CONFIG_HID_EZKEY is not set
# CONFIG_HID_HOLTEK is not set
# CONFIG_HID_HUION is not set
# CONFIG_HID_KEYTOUCH is not set
# CONFIG_HID_KYE is not set
# CONFIG_HID_UCLOGIC is not set
# CONFIG_HID_WALTOP is not set
# CONFIG_HID_GYRATION is not set
# CONFIG_HID_ICADE is not set
# CONFIG_HID_TWINHAN is not set
# CONFIG_HID_KENSINGTON is not set
# CONFIG_HID_LCPOWER is not set
# CONFIG_HID_LENOVO is not set
# CONFIG_HID_LOGITECH is not set
# CONFIG_HID_MAGICMOUSE is not set
# CONFIG_HID_MICROSOFT is not set
# CONFIG_HID_MONTEREY is not set
# CONFIG_HID_MULTITOUCH is not set
# CONFIG_HID_NTRIG is not set
# CONFIG_HID_ORTEK is not set
# CONFIG_HID_PANTHERLORD is not set
# CONFIG_HID_PENMOUNT is not set
# CONFIG_HID_PETALYNX is not set
# CONFIG_HID_PICOLCD is not set
# CONFIG_HID_PLANTRONICS is not set
# CONFIG_HID_PRIMAX is not set
# CONFIG_HID_ROCCAT is not set
# CONFIG_HID_SAITEK is not set
# CONFIG_HID_SAMSUNG is not set
# CONFIG_HID_SPEEDLINK is not set
# CONFIG_HID_STEELSERIES is not set
# CONFIG_HID_SUNPLUS is not set
# CONFIG_HID_RMI is not set
# CONFIG_HID_GREENASIA is not set
# CONFIG_HID_SMARTJOYPLUS is not set
# CONFIG_HID_TIVO is not set
# CONFIG_HID_TOPSEED is not set
# CONFIG_HID_THRUSTMASTER is not set
# CONFIG_HID_WACOM is not set
# CONFIG_HID_XINMO is not set
# CONFIG_HID_ZEROPLUS is not set
# CONFIG_HID_ZYDACRON is not set
# CONFIG_HID_SENSOR_HUB is not set

#
# USB HID support
#
CONFIG_USB_HID=y
# CONFIG_HID_PID is not set
# CONFIG_USB_HIDDEV is not set

#
# I2C HID support
#
# CONFIG_I2C_HID is not set
CONFIG_USB_OHCI_LITTLE_ENDIAN=y
CONFIG_USB_SUPPORT=y
CONFIG_USB_COMMON=y
CONFIG_USB_ARCH_HAS_HCD=y
CONFIG_USB=y
# CONFIG_USB_ANNOUNCE_NEW_DEVICES is not set

#
# Miscellaneous USB options
#
CONFIG_USB_DEFAULT_PERSIST=y
# CONFIG_USB_DYNAMIC_MINORS is not set
# CONFIG_USB_OTG is not set
# CONFIG_USB_OTG_WHITELIST is not set
# CONFIG_USB_OTG_BLACKLIST_HUB is not set
# CONFIG_USB_OTG_FSM is not set
# CONFIG_USB_MON is not set
# CONFIG_USB_WUSB_CBAF is not set

#
# USB Host Controller Drivers
#
# CONFIG_USB_C67X00_HCD is not set
# CONFIG_USB_XHCI_HCD is not set
# CONFIG_USB_EHCI_HCD is not set
# CONFIG_USB_OXU210HP_HCD is not set
# CONFIG_USB_ISP116X_HCD is not set
# CONFIG_USB_ISP1760_HCD is not set
# CONFIG_USB_ISP1362_HCD is not set
# CONFIG_USB_FUSBH200_HCD is not set
# CONFIG_USB_FOTG210_HCD is not set
# CONFIG_USB_OHCI_HCD is not set
# CONFIG_USB_UHCI_HCD is not set
# CONFIG_USB_SL811_HCD is not set
# CONFIG_USB_R8A66597_HCD is not set
# CONFIG_USB_HCD_TEST_MODE is not set

#
# USB Device Class drivers
#
# CONFIG_USB_ACM is not set
# CONFIG_USB_PRINTER is not set
# CONFIG_USB_WDM is not set
# CONFIG_USB_TMC is not set

#
# NOTE: USB_STORAGE depends on SCSI but BLK_DEV_SD may
#

#
# also be needed; see USB_STORAGE Help for more info
#
CONFIG_USB_STORAGE=y
# CONFIG_USB_STORAGE_DEBUG is not set
# CONFIG_USB_STORAGE_REALTEK is not set
# CONFIG_USB_STORAGE_DATAFAB is not set
# CONFIG_USB_STORAGE_FREECOM is not set
# CONFIG_USB_STORAGE_ISD200 is not set
# CONFIG_USB_STORAGE_USBAT is not set
# CONFIG_USB_STORAGE_SDDR09 is not set
# CONFIG_USB_STORAGE_SDDR55 is not set
# CONFIG_USB_STORAGE_JUMPSHOT is not set
# CONFIG_USB_STORAGE_ALAUDA is not set
# CONFIG_USB_STORAGE_ONETOUCH is not set
# CONFIG_USB_STORAGE_KARMA is not set
# CONFIG_USB_STORAGE_CYPRESS_ATACB is not set
# CONFIG_USB_STORAGE_ENE_UB6250 is not set
# CONFIG_USB_UAS is not set

#
# USB Imaging devices
#
# CONFIG_USB_MDC800 is not set
# CONFIG_USB_MICROTEK is not set
# CONFIG_USBIP_CORE is not set
# CONFIG_USB_MUSB_HDRC is not set
# CONFIG_USB_DWC3 is not set
# CONFIG_USB_DWC2 is not set

#
# USB port drivers
#
# CONFIG_USB_SERIAL is not set

#
# USB Miscellaneous drivers
#
# CONFIG_USB_EMI62 is not set
# CONFIG_USB_EMI26 is not set
# CONFIG_USB_ADUTUX is not set
# CONFIG_USB_SEVSEG is not set
# CONFIG_USB_RIO500 is not set
# CONFIG_USB_LEGOTOWER is not set
# CONFIG_USB_LCD is not set
# CONFIG_USB_LED is not set
# CONFIG_USB_CYPRESS_CY7C63 is not set
# CONFIG_USB_CYTHERM is not set
# CONFIG_USB_IDMOUSE is not set
# CONFIG_USB_FTDI_ELAN is not set
# CONFIG_USB_APPLEDISPLAY is not set
# CONFIG_USB_LD is not set
# CONFIG_USB_TRANCEVIBRATOR is not set
# CONFIG_USB_IOWARRIOR is not set
# CONFIG_USB_TEST is not set
# CONFIG_USB_EHSET_TEST_FIXTURE is not set
# CONFIG_USB_ISIGHTFW is not set
# CONFIG_USB_YUREX is not set
# CONFIG_USB_EZUSB_FX2 is not set
# CONFIG_USB_HSIC_USB3503 is not set
# CONFIG_USB_LINK_LAYER_TEST is not set

#
# USB Physical Layer drivers
#
# CONFIG_USB_PHY is not set
# CONFIG_NOP_USB_XCEIV is not set
# CONFIG_USB_GPIO_VBUS is not set
# CONFIG_USB_ISP1301 is not set
# CONFIG_USB_ULPI is not set
# CONFIG_USB_GADGET is not set
# CONFIG_UWB is not set
CONFIG_MMC=y
# CONFIG_MMC_DEBUG is not set
# CONFIG_MMC_CLKGATE is not set

#
# MMC/SD/SDIO Card Drivers
#
CONFIG_MMC_BLOCK=y
CONFIG_MMC_BLOCK_MINORS=8
CONFIG_MMC_BLOCK_BOUNCE=y
# CONFIG_SDIO_UART is not set
# CONFIG_MMC_TEST is not set

#
# MMC/SD/SDIO Host Controller Drivers
#
CONFIG_MMC_ARMMMCI=y
CONFIG_MMC_SDHCI=y
# CONFIG_MMC_SDHCI_PCI is not set
CONFIG_MMC_SDHCI_PLTFM=y
# CONFIG_MMC_SDHCI_OF_ARASAN is not set
# CONFIG_MMC_SDHCI_PXAV3 is not set
# CONFIG_MMC_SDHCI_PXAV2 is not set
# CONFIG_MMC_TIFM_SD is not set
# CONFIG_MMC_CB710 is not set
# CONFIG_MMC_VIA_SDMMC is not set
# CONFIG_MMC_DW is not set
# CONFIG_MMC_VUB300 is not set
# CONFIG_MMC_USHC is not set
# CONFIG_MMC_USDHI6ROL0 is not set
# CONFIG_MMC_TOSHIBA_PCI is not set
# CONFIG_MEMSTICK is not set
# CONFIG_NEW_LEDS is not set
# CONFIG_ACCESSIBILITY is not set
# CONFIG_INFINIBAND is not set
CONFIG_RTC_LIB=y
# CONFIG_RTC_CLASS is not set
# CONFIG_DMADEVICES is not set
# CONFIG_AUXDISPLAY is not set
# CONFIG_UIO is not set
# CONFIG_VIRT_DRIVERS is not set

#
# Virtio drivers
#
# CONFIG_VIRTIO_PCI is not set
# CONFIG_VIRTIO_MMIO is not set

#
# Microsoft Hyper-V guest support
#

#
# Xen driver support
#
CONFIG_XEN_BALLOON=y
CONFIG_XEN_SCRUB_PAGES=y
CONFIG_XEN_DEV_EVTCHN=y
CONFIG_XEN_BACKEND=y
CONFIG_XENFS=y
CONFIG_XEN_COMPAT_XENFS=y
CONFIG_XEN_SYS_HYPERVISOR=y
CONFIG_XEN_XENBUS_FRONTEND=y
CONFIG_XEN_GNTDEV=y
CONFIG_XEN_GRANT_DEV_ALLOC=y
CONFIG_SWIOTLB_XEN=y
CONFIG_XEN_PRIVCMD=y
# CONFIG_STAGING is not set

#
# SOC (System On Chip) specific Drivers
#
# CONFIG_SOC_TI is not set
CONFIG_CLKDEV_LOOKUP=y
CONFIG_HAVE_CLK_PREPARE=y
CONFIG_COMMON_CLK=y

#
# Common Clock Framework
#
CONFIG_COMMON_CLK_VERSATILE=y
CONFIG_CLK_SP810=y
CONFIG_CLK_VEXPRESS_OSC=y
# CONFIG_COMMON_CLK_SI5351 is not set
# CONFIG_COMMON_CLK_SI570 is not set
CONFIG_COMMON_CLK_XGENE=y
# CONFIG_COMMON_CLK_PXA is not set
# CONFIG_COMMON_CLK_QCOM is not set

#
# Hardware Spinlock drivers
#

#
# Clock Source drivers
#
CONFIG_CLKSRC_OF=y
CONFIG_CLKSRC_MMIO=y
CONFIG_ARM_ARCH_TIMER=y
CONFIG_ARM_ARCH_TIMER_EVTSTREAM=y
# CONFIG_ATMEL_PIT is not set
# CONFIG_SH_TIMER_CMT is not set
# CONFIG_SH_TIMER_MTU2 is not set
# CONFIG_SH_TIMER_TMU is not set
# CONFIG_EM_TIMER_STI is not set
CONFIG_CLKSRC_VERSATILE=y
CONFIG_MAILBOX=y
CONFIG_PL320_MBOX=y
CONFIG_IOMMU_SUPPORT=y
# CONFIG_ARM_SMMU is not set

#
# Remoteproc drivers
#
# CONFIG_STE_MODEM_RPROC is not set

#
# Rpmsg drivers
#

#
# SOC (System On Chip) specific Drivers
#
# CONFIG_PM_DEVFREQ is not set
# CONFIG_EXTCON is not set
# CONFIG_MEMORY is not set
# CONFIG_IIO is not set
# CONFIG_VME_BUS is not set
# CONFIG_PWM is not set
CONFIG_IRQCHIP=y
CONFIG_ARM_GIC=y
CONFIG_ARM_GIC_V2M=y
CONFIG_ARM_GIC_V3=y
CONFIG_ARM_GIC_V3_ITS=y
# CONFIG_IPACK_BUS is not set
# CONFIG_RESET_CONTROLLER is not set
# CONFIG_FMC is not set

#
# PHY Subsystem
#
# CONFIG_GENERIC_PHY is not set
# CONFIG_BCM_KONA_USB2_PHY is not set
# CONFIG_PHY_XGENE is not set
# CONFIG_POWERCAP is not set
# CONFIG_MCB is not set
CONFIG_RAS=y
# CONFIG_THUNDERBOLT is not set

#
# Android
#
# CONFIG_ANDROID is not set

#
# Firmware Drivers
#
# CONFIG_FIRMWARE_MEMMAP is not set
CONFIG_DMIID=y
# CONFIG_DMI_SYSFS is not set

#
# EFI (Extensible Firmware Interface) Support
#
# CONFIG_EFI_VARS is not set
CONFIG_EFI_PARAMS_FROM_FDT=y
CONFIG_EFI_RUNTIME_WRAPPERS=y
CONFIG_EFI_ARMSTUB=y

#
# File systems
#
CONFIG_DCACHE_WORD_ACCESS=y
CONFIG_EXT2_FS=y
# CONFIG_EXT2_FS_XATTR is not set
# CONFIG_EXT2_FS_XIP is not set
CONFIG_EXT3_FS=y
CONFIG_EXT3_DEFAULTS_TO_ORDERED=y
CONFIG_EXT3_FS_XATTR=y
# CONFIG_EXT3_FS_POSIX_ACL is not set
# CONFIG_EXT3_FS_SECURITY is not set
CONFIG_EXT4_FS=y
# CONFIG_EXT4_FS_POSIX_ACL is not set
# CONFIG_EXT4_FS_SECURITY is not set
# CONFIG_EXT4_DEBUG is not set
CONFIG_JBD=y
# CONFIG_JBD_DEBUG is not set
CONFIG_JBD2=y
# CONFIG_JBD2_DEBUG is not set
CONFIG_FS_MBCACHE=y
# CONFIG_REISERFS_FS is not set
# CONFIG_JFS_FS is not set
# CONFIG_XFS_FS is not set
# CONFIG_GFS2_FS is not set
# CONFIG_BTRFS_FS is not set
# CONFIG_NILFS2_FS is not set
CONFIG_FS_POSIX_ACL=y
CONFIG_EXPORTFS=y
CONFIG_FILE_LOCKING=y
CONFIG_FSNOTIFY=y
CONFIG_DNOTIFY=y
CONFIG_INOTIFY_USER=y
# CONFIG_FANOTIFY is not set
# CONFIG_QUOTA is not set
# CONFIG_QUOTACTL is not set
# CONFIG_AUTOFS4_FS is not set
# CONFIG_FUSE_FS is not set
# CONFIG_OVERLAY_FS is not set

#
# Caches
#
# CONFIG_FSCACHE is not set

#
# CD-ROM/DVD Filesystems
#
# CONFIG_ISO9660_FS is not set
# CONFIG_UDF_FS is not set

#
# DOS/FAT/NT Filesystems
#
CONFIG_FAT_FS=y
# CONFIG_MSDOS_FS is not set
CONFIG_VFAT_FS=y
CONFIG_FAT_DEFAULT_CODEPAGE=437
CONFIG_FAT_DEFAULT_IOCHARSET="iso8859-1"
# CONFIG_NTFS_FS is not set

#
# Pseudo filesystems
#
CONFIG_PROC_FS=y
# CONFIG_PROC_KCORE is not set
CONFIG_PROC_SYSCTL=y
CONFIG_PROC_PAGE_MONITOR=y
CONFIG_KERNFS=y
CONFIG_SYSFS=y
CONFIG_TMPFS=y
CONFIG_TMPFS_POSIX_ACL=y
CONFIG_TMPFS_XATTR=y
# CONFIG_HUGETLBFS is not set
# CONFIG_HUGETLB_PAGE is not set
# CONFIG_CONFIGFS_FS is not set
CONFIG_MISC_FILESYSTEMS=y
# CONFIG_ADFS_FS is not set
# CONFIG_AFFS_FS is not set
# CONFIG_HFS_FS is not set
# CONFIG_HFSPLUS_FS is not set
# CONFIG_BEFS_FS is not set
# CONFIG_BFS_FS is not set
# CONFIG_EFS_FS is not set
CONFIG_JFFS2_FS=y
CONFIG_JFFS2_FS_DEBUG=0
CONFIG_JFFS2_FS_WRITEBUFFER=y
# CONFIG_JFFS2_FS_WBUF_VERIFY is not set
# CONFIG_JFFS2_SUMMARY is not set
# CONFIG_JFFS2_FS_XATTR is not set
# CONFIG_JFFS2_COMPRESSION_OPTIONS is not set
CONFIG_JFFS2_ZLIB=y
# CONFIG_JFFS2_LZO is not set
CONFIG_JFFS2_RTIME=y
# CONFIG_JFFS2_RUBIN is not set
# CONFIG_LOGFS is not set
CONFIG_CRAMFS=y
# CONFIG_SQUASHFS is not set
# CONFIG_VXFS_FS is not set
CONFIG_MINIX_FS=y
# CONFIG_OMFS_FS is not set
# CONFIG_HPFS_FS is not set
# CONFIG_QNX4FS_FS is not set
# CONFIG_QNX6FS_FS is not set
CONFIG_ROMFS_FS=y
CONFIG_ROMFS_BACKED_BY_BLOCK=y
# CONFIG_ROMFS_BACKED_BY_MTD is not set
# CONFIG_ROMFS_BACKED_BY_BOTH is not set
CONFIG_ROMFS_ON_BLOCK=y
# CONFIG_PSTORE is not set
# CONFIG_SYSV_FS is not set
# CONFIG_UFS_FS is not set
# CONFIG_F2FS_FS is not set
# CONFIG_EFIVAR_FS is not set
CONFIG_NETWORK_FILESYSTEMS=y
CONFIG_NFS_FS=y
CONFIG_NFS_V2=y
CONFIG_NFS_V3=y
# CONFIG_NFS_V3_ACL is not set
# CONFIG_NFS_V4 is not set
# CONFIG_NFS_SWAP is not set
CONFIG_ROOT_NFS=y
CONFIG_NFSD=y
CONFIG_NFSD_V3=y
# CONFIG_NFSD_V3_ACL is not set
# CONFIG_NFSD_V4 is not set
CONFIG_GRACE_PERIOD=y
CONFIG_LOCKD=y
CONFIG_LOCKD_V4=y
CONFIG_NFS_COMMON=y
CONFIG_SUNRPC=y
# CONFIG_SUNRPC_DEBUG is not set
# CONFIG_CEPH_FS is not set
# CONFIG_CIFS is not set
# CONFIG_NCP_FS is not set
# CONFIG_CODA_FS is not set
# CONFIG_AFS_FS is not set
CONFIG_NLS=y
CONFIG_NLS_DEFAULT="iso8859-1"
# CONFIG_NLS_CODEPAGE_437 is not set
# CONFIG_NLS_CODEPAGE_737 is not set
# CONFIG_NLS_CODEPAGE_775 is not set
CONFIG_NLS_CODEPAGE_850=y
# CONFIG_NLS_CODEPAGE_852 is not set
# CONFIG_NLS_CODEPAGE_855 is not set
# CONFIG_NLS_CODEPAGE_857 is not set
# CONFIG_NLS_CODEPAGE_860 is not set
# CONFIG_NLS_CODEPAGE_861 is not set
# CONFIG_NLS_CODEPAGE_862 is not set
# CONFIG_NLS_CODEPAGE_863 is not set
# CONFIG_NLS_CODEPAGE_864 is not set
# CONFIG_NLS_CODEPAGE_865 is not set
# CONFIG_NLS_CODEPAGE_866 is not set
# CONFIG_NLS_CODEPAGE_869 is not set
# CONFIG_NLS_CODEPAGE_936 is not set
# CONFIG_NLS_CODEPAGE_950 is not set
# CONFIG_NLS_CODEPAGE_932 is not set
# CONFIG_NLS_CODEPAGE_949 is not set
# CONFIG_NLS_CODEPAGE_874 is not set
# CONFIG_NLS_ISO8859_8 is not set
# CONFIG_NLS_CODEPAGE_1250 is not set
# CONFIG_NLS_CODEPAGE_1251 is not set
# CONFIG_NLS_ASCII is not set
CONFIG_NLS_ISO8859_1=y
# CONFIG_NLS_ISO8859_2 is not set
# CONFIG_NLS_ISO8859_3 is not set
# CONFIG_NLS_ISO8859_4 is not set
# CONFIG_NLS_ISO8859_5 is not set
# CONFIG_NLS_ISO8859_6 is not set
# CONFIG_NLS_ISO8859_7 is not set
# CONFIG_NLS_ISO8859_9 is not set
# CONFIG_NLS_ISO8859_13 is not set
# CONFIG_NLS_ISO8859_14 is not set
# CONFIG_NLS_ISO8859_15 is not set
# CONFIG_NLS_KOI8_R is not set
# CONFIG_NLS_KOI8_U is not set
# CONFIG_NLS_MAC_ROMAN is not set
# CONFIG_NLS_MAC_CELTIC is not set
# CONFIG_NLS_MAC_CENTEURO is not set
# CONFIG_NLS_MAC_CROATIAN is not set
# CONFIG_NLS_MAC_CYRILLIC is not set
# CONFIG_NLS_MAC_GAELIC is not set
# CONFIG_NLS_MAC_GREEK is not set
# CONFIG_NLS_MAC_ICELAND is not set
# CONFIG_NLS_MAC_INUIT is not set
# CONFIG_NLS_MAC_ROMANIAN is not set
# CONFIG_NLS_MAC_TURKISH is not set
# CONFIG_NLS_UTF8 is not set
# CONFIG_VIRTUALIZATION is not set

#
# Kernel hacking
#

#
# printk and dmesg options
#
# CONFIG_PRINTK_TIME is not set
CONFIG_MESSAGE_LOGLEVEL_DEFAULT=4
# CONFIG_BOOT_PRINTK_DELAY is not set
# CONFIG_DYNAMIC_DEBUG is not set

#
# Compile-time checks and compiler options
#
# CONFIG_DEBUG_INFO is not set
CONFIG_ENABLE_WARN_DEPRECATED=y
CONFIG_ENABLE_MUST_CHECK=y
CONFIG_FRAME_WARN=1024
# CONFIG_STRIP_ASM_SYMS is not set
# CONFIG_READABLE_ASM is not set
# CONFIG_UNUSED_SYMBOLS is not set
# CONFIG_PAGE_OWNER is not set
CONFIG_DEBUG_FS=y
# CONFIG_HEADERS_CHECK is not set
# CONFIG_DEBUG_SECTION_MISMATCH is not set
CONFIG_ARCH_WANT_FRAME_POINTERS=y
CONFIG_FRAME_POINTER=y
# CONFIG_DEBUG_FORCE_WEAK_PER_CPU is not set
CONFIG_MAGIC_SYSRQ=y
CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE=0x1
CONFIG_DEBUG_KERNEL=y

#
# Memory Debugging
#
# CONFIG_PAGE_EXTENSION is not set
# CONFIG_DEBUG_PAGEALLOC is not set
# CONFIG_DEBUG_OBJECTS is not set
# CONFIG_DEBUG_SLAB is not set
CONFIG_HAVE_DEBUG_KMEMLEAK=y
# CONFIG_DEBUG_KMEMLEAK is not set
# CONFIG_DEBUG_STACK_USAGE is not set
# CONFIG_DEBUG_VM is not set
# CONFIG_DEBUG_MEMORY_INIT is not set
# CONFIG_DEBUG_PER_CPU_MAPS is not set
# CONFIG_DEBUG_SHIRQ is not set

#
# Debug Lockups and Hangs
#
# CONFIG_LOCKUP_DETECTOR is not set
# CONFIG_DETECT_HUNG_TASK is not set
# CONFIG_PANIC_ON_OOPS is not set
CONFIG_PANIC_ON_OOPS_VALUE=0
CONFIG_PANIC_TIMEOUT=0
CONFIG_SCHED_DEBUG=y
# CONFIG_SCHEDSTATS is not set
# CONFIG_SCHED_STACK_END_CHECK is not set
# CONFIG_TIMER_STATS is not set

#
# Lock Debugging (spinlocks, mutexes, etc...)
#
# CONFIG_DEBUG_RT_MUTEXES is not set
# CONFIG_DEBUG_SPINLOCK is not set
# CONFIG_DEBUG_MUTEXES is not set
# CONFIG_DEBUG_WW_MUTEX_SLOWPATH is not set
# CONFIG_DEBUG_LOCK_ALLOC is not set
# CONFIG_PROVE_LOCKING is not set
# CONFIG_LOCK_STAT is not set
# CONFIG_DEBUG_ATOMIC_SLEEP is not set
# CONFIG_DEBUG_LOCKING_API_SELFTESTS is not set
# CONFIG_LOCK_TORTURE_TEST is not set
# CONFIG_STACKTRACE is not set
# CONFIG_DEBUG_KOBJECT is not set
CONFIG_HAVE_DEBUG_BUGVERBOSE=y
CONFIG_DEBUG_BUGVERBOSE=y
# CONFIG_DEBUG_LIST is not set
# CONFIG_DEBUG_PI_LIST is not set
# CONFIG_DEBUG_SG is not set
# CONFIG_DEBUG_NOTIFIERS is not set
# CONFIG_DEBUG_CREDENTIALS is not set

#
# RCU Debugging
#
# CONFIG_SPARSE_RCU_POINTER is not set
# CONFIG_TORTURE_TEST is not set
# CONFIG_RCU_TORTURE_TEST is not set
CONFIG_RCU_CPU_STALL_TIMEOUT=21
# CONFIG_RCU_CPU_STALL_INFO is not set
# CONFIG_RCU_TRACE is not set
# CONFIG_DEBUG_BLOCK_EXT_DEVT is not set
# CONFIG_NOTIFIER_ERROR_INJECTION is not set
# CONFIG_FAULT_INJECTION is not set
CONFIG_HAVE_FUNCTION_TRACER=y
CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y
CONFIG_HAVE_DYNAMIC_FTRACE=y
CONFIG_HAVE_FTRACE_MCOUNT_RECORD=y
CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
CONFIG_HAVE_C_RECORDMCOUNT=y
CONFIG_TRACING_SUPPORT=y
CONFIG_FTRACE=y
# CONFIG_FUNCTION_TRACER is not set
# CONFIG_IRQSOFF_TRACER is not set
# CONFIG_SCHED_TRACER is not set
# CONFIG_ENABLE_DEFAULT_TRACERS is not set
# CONFIG_FTRACE_SYSCALLS is not set
# CONFIG_TRACER_SNAPSHOT is not set
CONFIG_BRANCH_PROFILE_NONE=y
# CONFIG_PROFILE_ANNOTATED_BRANCHES is not set
# CONFIG_PROFILE_ALL_BRANCHES is not set
# CONFIG_STACK_TRACER is not set
# CONFIG_BLK_DEV_IO_TRACE is not set
# CONFIG_PROBE_EVENTS is not set
# CONFIG_TRACEPOINT_BENCHMARK is not set

#
# Runtime Testing
#
# CONFIG_LKDTM is not set
# CONFIG_TEST_LIST_SORT is not set
# CONFIG_BACKTRACE_SELF_TEST is not set
# CONFIG_RBTREE_TEST is not set
# CONFIG_ATOMIC64_SELFTEST is not set
# CONFIG_TEST_STRING_HELPERS is not set
# CONFIG_TEST_KSTRTOX is not set
# CONFIG_TEST_RHASHTABLE is not set
# CONFIG_DMA_API_DEBUG is not set
# CONFIG_TEST_FIRMWARE is not set
# CONFIG_TEST_UDELAY is not set
# CONFIG_SAMPLES is not set
CONFIG_HAVE_ARCH_KGDB=y
# CONFIG_KGDB is not set
# CONFIG_ARM64_PTDUMP is not set
# CONFIG_STRICT_DEVMEM is not set
# CONFIG_PID_IN_CONTEXTIDR is not set
# CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET is not set

#
# Security options
#
# CONFIG_KEYS is not set
# CONFIG_SECURITY_DMESG_RESTRICT is not set
# CONFIG_SECURITY is not set
# CONFIG_SECURITYFS is not set
CONFIG_DEFAULT_SECURITY_DAC=y
CONFIG_DEFAULT_SECURITY=""
CONFIG_CRYPTO=y

#
# Crypto core or helper
#
CONFIG_CRYPTO_ALGAPI=y
CONFIG_CRYPTO_ALGAPI2=y
CONFIG_CRYPTO_AEAD2=y
CONFIG_CRYPTO_BLKCIPHER=y
CONFIG_CRYPTO_BLKCIPHER2=y
CONFIG_CRYPTO_HASH=y
CONFIG_CRYPTO_HASH2=y
CONFIG_CRYPTO_RNG=y
CONFIG_CRYPTO_RNG2=y
CONFIG_CRYPTO_PCOMP2=y
CONFIG_CRYPTO_MANAGER=y
CONFIG_CRYPTO_MANAGER2=y
# CONFIG_CRYPTO_USER is not set
CONFIG_CRYPTO_MANAGER_DISABLE_TESTS=y
# CONFIG_CRYPTO_GF128MUL is not set
# CONFIG_CRYPTO_NULL is not set
# CONFIG_CRYPTO_PCRYPT is not set
CONFIG_CRYPTO_WORKQUEUE=y
# CONFIG_CRYPTO_CRYPTD is not set
# CONFIG_CRYPTO_MCRYPTD is not set
# CONFIG_CRYPTO_AUTHENC is not set

#
# Authenticated Encryption with Associated Data
#
# CONFIG_CRYPTO_CCM is not set
# CONFIG_CRYPTO_GCM is not set
# CONFIG_CRYPTO_SEQIV is not set

#
# Block modes
#
CONFIG_CRYPTO_CBC=y
# CONFIG_CRYPTO_CTR is not set
# CONFIG_CRYPTO_CTS is not set
# CONFIG_CRYPTO_ECB is not set
# CONFIG_CRYPTO_LRW is not set
# CONFIG_CRYPTO_PCBC is not set
# CONFIG_CRYPTO_XTS is not set

#
# Hash modes
#
# CONFIG_CRYPTO_CMAC is not set
# CONFIG_CRYPTO_HMAC is not set
# CONFIG_CRYPTO_XCBC is not set
# CONFIG_CRYPTO_VMAC is not set

#
# Digest
#
CONFIG_CRYPTO_CRC32C=y
# CONFIG_CRYPTO_CRC32 is not set
# CONFIG_CRYPTO_CRCT10DIF is not set
# CONFIG_CRYPTO_GHASH is not set
# CONFIG_CRYPTO_MD4 is not set
CONFIG_CRYPTO_MD5=y
# CONFIG_CRYPTO_MICHAEL_MIC is not set
# CONFIG_CRYPTO_RMD128 is not set
# CONFIG_CRYPTO_RMD160 is not set
# CONFIG_CRYPTO_RMD256 is not set
# CONFIG_CRYPTO_RMD320 is not set
# CONFIG_CRYPTO_SHA1 is not set
# CONFIG_CRYPTO_SHA256 is not set
# CONFIG_CRYPTO_SHA512 is not set
# CONFIG_CRYPTO_TGR192 is not set
# CONFIG_CRYPTO_WP512 is not set

#
# Ciphers
#
CONFIG_CRYPTO_AES=y
# CONFIG_CRYPTO_ANUBIS is not set
# CONFIG_CRYPTO_ARC4 is not set
# CONFIG_CRYPTO_BLOWFISH is not set
# CONFIG_CRYPTO_CAMELLIA is not set
# CONFIG_CRYPTO_CAST5 is not set
# CONFIG_CRYPTO_CAST6 is not set
CONFIG_CRYPTO_DES=y
# CONFIG_CRYPTO_FCRYPT is not set
# CONFIG_CRYPTO_KHAZAD is not set
# CONFIG_CRYPTO_SALSA20 is not set
# CONFIG_CRYPTO_SEED is not set
# CONFIG_CRYPTO_SERPENT is not set
# CONFIG_CRYPTO_TEA is not set
# CONFIG_CRYPTO_TWOFISH is not set

#
# Compression
#
# CONFIG_CRYPTO_DEFLATE is not set
# CONFIG_CRYPTO_ZLIB is not set
# CONFIG_CRYPTO_LZO is not set
# CONFIG_CRYPTO_LZ4 is not set
# CONFIG_CRYPTO_LZ4HC is not set

#
# Random Number Generation
#
CONFIG_CRYPTO_ANSI_CPRNG=y
# CONFIG_CRYPTO_DRBG_MENU is not set
# CONFIG_CRYPTO_USER_API_HASH is not set
# CONFIG_CRYPTO_USER_API_SKCIPHER is not set
CONFIG_CRYPTO_HW=y
# CONFIG_CRYPTO_DEV_CCP is not set
# CONFIG_ARM64_CRYPTO is not set
# CONFIG_BINARY_PRINTF is not set

#
# Library routines
#
CONFIG_BITREVERSE=y
CONFIG_GENERIC_STRNCPY_FROM_USER=y
CONFIG_GENERIC_STRNLEN_USER=y
CONFIG_GENERIC_NET_UTILS=y
CONFIG_GENERIC_PCI_IOMAP=y
CONFIG_GENERIC_IO=y
CONFIG_ARCH_USE_CMPXCHG_LOCKREF=y
# CONFIG_CRC_CCITT is not set
CONFIG_CRC16=y
# CONFIG_CRC_T10DIF is not set
# CONFIG_CRC_ITU_T is not set
CONFIG_CRC32=y
# CONFIG_CRC32_SELFTEST is not set
CONFIG_CRC32_SLICEBY8=y
# CONFIG_CRC32_SLICEBY4 is not set
# CONFIG_CRC32_SARWATE is not set
# CONFIG_CRC32_BIT is not set
# CONFIG_CRC7 is not set
CONFIG_LIBCRC32C=y
# CONFIG_CRC8 is not set
CONFIG_AUDIT_ARCH_COMPAT_GENERIC=y
# CONFIG_RANDOM32_SELFTEST is not set
CONFIG_ZLIB_INFLATE=y
CONFIG_ZLIB_DEFLATE=y
CONFIG_LZO_COMPRESS=y
CONFIG_LZO_DECOMPRESS=y
CONFIG_XZ_DEC=y
CONFIG_XZ_DEC_X86=y
CONFIG_XZ_DEC_POWERPC=y
CONFIG_XZ_DEC_IA64=y
CONFIG_XZ_DEC_ARM=y
CONFIG_XZ_DEC_ARMTHUMB=y
CONFIG_XZ_DEC_SPARC=y
CONFIG_XZ_DEC_BCJ=y
# CONFIG_XZ_DEC_TEST is not set
CONFIG_DECOMPRESS_GZIP=y
CONFIG_GENERIC_ALLOCATOR=y
CONFIG_HAS_IOMEM=y
CONFIG_HAS_IOPORT_MAP=y
CONFIG_HAS_DMA=y
CONFIG_CPU_RMAP=y
CONFIG_DQL=y
CONFIG_GLOB=y
# CONFIG_GLOB_SELFTEST is not set
CONFIG_NLATTR=y
CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE=y
# CONFIG_AVERAGE is not set
# CONFIG_CORDIC is not set
# CONFIG_DDR is not set
CONFIG_LIBFDT=y
CONFIG_UCS2_STRING=y
CONFIG_FONT_SUPPORT=y
CONFIG_FONTS=y
# CONFIG_FONT_8x8 is not set
# CONFIG_FONT_8x16 is not set
# CONFIG_FONT_6x11 is not set
# CONFIG_FONT_7x14 is not set
# CONFIG_FONT_PEARL_8x8 is not set
CONFIG_FONT_ACORN_8x8=y
# CONFIG_FONT_MINI_4x6 is not set
# CONFIG_FONT_6x10 is not set
# CONFIG_FONT_SUN8x16 is not set
# CONFIG_FONT_SUN12x22 is not set
# CONFIG_FONT_10x18 is not set
CONFIG_ARCH_HAS_SG_CHAIN=y
CONFIG_IOMMU_DMA=y

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Robin Murphy]

On 13/01/15 11:08, Stefano Stabellini wrote:
> On Mon, 12 Jan 2015, Robin Murphy wrote:
>> Hi all,
>>
>> Whilst it's a long way off perfect, this has reached the point of being
>> functional and stable enough to be useful, so here it is. The core
>> consists of the meat of the arch/arm implementation modified to remove
>> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
>> allocator instead of the bitmap-based one. For that, this series depends
>> on my "Genericise the IOVA allocator" series posted earlier[1].
>>
>> There are plenty of obvious things still to do, including:
>>
>>   * Domain and group handling is all wrong, but that's a bigger problem.
>>     For the moment it does more or less the same thing as the arch/arm
>>     code, which at least works for the one-IOMMU-per-device situation.
>>   * IOMMU domains and IOVA domains probably want to be better integrated
>>     with devices and each other, rather than having a proliferation of
>>     arch-specific structs.
>>   * The temporary map_sg implementation - I have a 'proper' iommu_map_sg
>>     based one in progress, but since the simple one works it's not been
>>     as high a priority.
>>   * Port arch/arm over to it. I'd guess it might be preferable to merge
>>     this through arm64 first, though, rather than overcomplicate matters.
>>   * There may well be scope for streamlining and tidying up the copied
>>     parts - In general I've simply avoided touching anything I don't
>>     fully understand.
>>   * In the same vein, I'm sure lots of it is fairly ARM-specific, so will
>>     need longer-term work to become truly generic.
>>
>> [1]:http://thread.gmane.org/gmane.linux.kernel.iommu/8208
>
> I tried to git-am and build a v3.19-rc4 kernel with this series (config
> file attached), but I get:
>
> In file included from include/linux/dma-mapping.h:82:0,
>                   from arch/arm64/kernel/asm-offsets.c:23:
> ./arch/arm64/include/asm/dma-mapping.h: In function ?phys_to_dma?:
> ./arch/arm64/include/asm/dma-mapping.h:69:2: error: ?struct dev_archdata? has no member named ?mapping?
> ./arch/arm64/include/asm/dma-mapping.h: In function ?dma_to_phys?:
> ./arch/arm64/include/asm/dma-mapping.h:81:19: error: ?struct dev_archdata? has no member named ?mapping?
> make[1]: *** [arch/arm64/kernel/asm-offsets.s] Error 1
>

Oops, looks like I've been relying on having an actual IOMMU driver 
select CONFIG_IOMMU_API - enabling the ARM SMMU driver as well as "IOMMU 
hardware support" makes everything build, even if it doesn't actually 
work with the new framework (the patches for that exist, but are 
currently a big ugly mess).

The nested #include guard in arch/arm64/include/asm/device.h in patch 4 
is to blame - on reflection, I guess that isn't a great idea regardless 
of the logical dependency (I don't think my Kconfig-fu is strong enough 
to guarantee that dependency is enforced).

Robin.

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Catalin Marinas]

On Mon, Jan 12, 2015 at 08:48:52PM +0000, Robin Murphy wrote:
> Catalin Marinas (1):
>   arm64: Combine coherent and non-coherent swiotlb dma_ops
> 
> Robin Murphy (4):
>   arm64: implement generic IOMMU configuration
>   iommu: implement common IOMMU ops for DMA mapping
>   arm64: add IOMMU dma_ops
>   arm64: hook up IOMMU dma_ops

I queued the first two patches in this series for 3.20. The rest need to
go through some review rounds.

Thanks.

-- 
Catalin

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Robin Murphy]

On 23/01/15 16:47, Catalin Marinas wrote:
> On Mon, Jan 12, 2015 at 08:48:52PM +0000, Robin Murphy wrote:
>> Catalin Marinas (1):
>>    arm64: Combine coherent and non-coherent swiotlb dma_ops
>>
>> Robin Murphy (4):
>>    arm64: implement generic IOMMU configuration
>>    iommu: implement common IOMMU ops for DMA mapping
>>    arm64: add IOMMU dma_ops
>>    arm64: hook up IOMMU dma_ops
>
> I queued the first two patches in this series for 3.20. The rest need to
> go through some review rounds.
>
> Thanks.
>

Thanks Catalin, the less to rebase the better ;)

Robin.

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Marek Szyprowski]

Hello,

On 2015-01-12 21:48, Robin Murphy wrote:
> Hi all,
>
> Whilst it's a long way off perfect, this has reached the point of being
> functional and stable enough to be useful, so here it is. The core
> consists of the meat of the arch/arm implementation modified to remove
> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
> allocator instead of the bitmap-based one. For that, this series depends
> on my "Genericise the IOVA allocator" series posted earlier[1].

I've tested your patches on Exynos 5433 based system and I have a few
comments. To get them working I had to do some fixes. Most of them
are already reported in this thread, the remaining I will send in a few
minutes.

Do you plan to send an updated patchset?

> There are plenty of obvious things still to do, including:
>
>   * Domain and group handling is all wrong, but that's a bigger problem.
>     For the moment it does more or less the same thing as the arch/arm
>     code, which at least works for the one-IOMMU-per-device situation.
>   * IOMMU domains and IOVA domains probably want to be better integrated
>     with devices and each other, rather than having a proliferation of
>     arch-specific structs.
>   * The temporary map_sg implementation - I have a 'proper' iommu_map_sg
>     based one in progress, but since the simple one works it's not been
>     as high a priority.

Well, for ARM arch this was the main feature of IOMMU and DMA-mapping
integration. It is heavily used by some multimedia devices and dma-buf
realted stuff to get a scattered buffer mapped into contiguous IO address
space.

>   * Port arch/arm over to it. I'd guess it might be preferable to merge
>     this through arm64 first, though, rather than overcomplicate matters.

I think that the code in arch/arm is already quite well tested and can be
almost directly reused for common dma-mapping helpers.

>   * There may well be scope for streamlining and tidying up the copied
>     parts - In general I've simply avoided touching anything I don't
>     fully understand.
>   * In the same vein, I'm sure lots of it is fairly ARM-specific, so will
>     need longer-term work to become truly generic.
>
> [1]:http://thread.gmane.org/gmane.linux.kernel.iommu/8208

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland

[RFC PATCH 0/5] arm64: IOMMU-backed DMA mapping

[Robin Murphy]

Hi Marek,

On 05/03/15 14:31, Marek Szyprowski wrote:
> Hello,
>
> On 2015-01-12 21:48, Robin Murphy wrote:
>> Hi all,
>>
>> Whilst it's a long way off perfect, this has reached the point of being
>> functional and stable enough to be useful, so here it is. The core
>> consists of the meat of the arch/arm implementation modified to remove
>> the assumption of PAGE_SIZE pages and ported over to the Intel IOVA
>> allocator instead of the bitmap-based one. For that, this series depends
>> on my "Genericise the IOVA allocator" series posted earlier[1].
>
> I've tested your patches on Exynos 5433 based system and I have a few
> comments. To get them working I had to do some fixes. Most of them
> are already reported in this thread, the remaining I will send in a few
> minutes.

Thanks!

> Do you plan to send an updated patchset?

I already sent a v2 which addressed some of the major issues here:

http://thread.gmane.org/gmane.linux.kernel.iommu/8773

Following some of the feedback there I've currently got a v3 in 
development, which reworks a lot of it more in favour of scatterlists, 
and fills in some of the gaps needed to move arch/arm over (I still need 
to look at how to handle the drivers currently making use of 
dma_iommu_mapping directly).

Robin.

>
>> There are plenty of obvious things still to do, including:
>>
>>    * Domain and group handling is all wrong, but that's a bigger problem.
>>      For the moment it does more or less the same thing as the arch/arm
>>      code, which at least works for the one-IOMMU-per-device situation.
>>    * IOMMU domains and IOVA domains probably want to be better integrated
>>      with devices and each other, rather than having a proliferation of
>>      arch-specific structs.
>>    * The temporary map_sg implementation - I have a 'proper' iommu_map_sg
>>      based one in progress, but since the simple one works it's not been
>>      as high a priority.
>
> Well, for ARM arch this was the main feature of IOMMU and DMA-mapping
> integration. It is heavily used by some multimedia devices and dma-buf
> realted stuff to get a scattered buffer mapped into contiguous IO address
> space.
>
>>    * Port arch/arm over to it. I'd guess it might be preferable to merge
>>      this through arm64 first, though, rather than overcomplicate matters.
>
> I think that the code in arch/arm is already quite well tested and can be
> almost directly reused for common dma-mapping helpers.
>
>>    * There may well be scope for streamlining and tidying up the copied
>>      parts - In general I've simply avoided touching anything I don't
>>      fully understand.
>>    * In the same vein, I'm sure lots of it is fairly ARM-specific, so will
>>      need longer-term work to become truly generic.
>>
>> [1]:http://thread.gmane.org/gmane.linux.kernel.iommu/8208
>
> Best regards
>