[PATCH v4 05/07] iommu/ipmmu-vmsa: Add new IOMMU_DOMAIN_DMA ops

Magnus Damm
2016-06-08T07:28:57Z

Introduce an alternative set of iommu_ops suitable for 64-bit ARM
as well as 32-bit ARM when CONFIG_IOMMU_DMA=y.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
---

Changes since V3:
- Removed group parameter from ipmmu_init_platform_device()

Changes since V2:
- Included this new patch from the following series:
[PATCH 00/04] iommu/ipmmu-vmsa: IPMMU CONFIG_IOMMU_DMA update
- Use only a single iommu_ops structure with #ifdef CONFIG_IOMMU_DMA
- Folded in #ifdefs to handle CONFIG_ARM and CONFIG_IOMMU_DMA
- of_xlate() is now used without #ifdefs
- Made sure code compiles on both 32-bit and 64-bit ARM.

drivers/iommu/ipmmu-vmsa.c | 111 ++++++++++++++++++++++++++++++++++++++++----
1 file changed, 103 insertions(+), 8 deletions(-)

--- 0008/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c 2016-06-08 15:08:39.950607110 +0900
@@ -10,6 +10,7 @@

#include <linux/bitmap.h>
#include <linux/delay.h>
+#include <linux/dma-iommu.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/export.h>
@@ -22,8 +23,10 @@
#include <linux/sizes.h>
#include <linux/slab.h>

+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
#include <asm/dma-iommu.h>
#include <asm/pgalloc.h>
+#endif

#include "io-pgtable.h"

@@ -520,14 +523,6 @@ static struct iommu_domain *__ipmmu_doma
return &domain->io_domain;
}

-static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
-{
- if (type != IOMMU_DOMAIN_UNMANAGED)
- return NULL;
-
- return __ipmmu_domain_alloc(type);
-}
-
static void ipmmu_domain_free(struct iommu_domain *io_domain)
{
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
@@ -714,6 +709,8 @@ error:
return ret;
}

+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
+
static int ipmmu_add_device(struct device *dev)
{
struct ipmmu_vmsa_archdata *archdata;
@@ -807,6 +804,14 @@ static void ipmmu_remove_device(struct d
dev->archdata.iommu = NULL;
}

+static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
+{
+ if (type != IOMMU_DOMAIN_UNMANAGED)
+ return NULL;
+
+ return __ipmmu_domain_alloc(type);
+}
+
static const struct iommu_ops ipmmu_ops = {
.domain_alloc = ipmmu_domain_alloc,
.domain_free = ipmmu_domain_free,
@@ -821,6 +826,94 @@ static const struct iommu_ops ipmmu_ops
.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
};

+#endif /* !CONFIG_ARM && CONFIG_IOMMU_DMA */
+
+#ifdef CONFIG_IOMMU_DMA
+
+static struct iommu_domain *ipmmu_domain_alloc_dma(unsigned type)
+{
+ struct iommu_domain *io_domain;
+
+ if (type != IOMMU_DOMAIN_DMA)
+ return NULL;
+
+ io_domain = __ipmmu_domain_alloc(type);
+ if (io_domain)
+ iommu_get_dma_cookie(io_domain);
+
+ return io_domain;
+}
+
+static void ipmmu_domain_free_dma(struct iommu_domain *io_domain)
+{
+ iommu_put_dma_cookie(io_domain);
+ ipmmu_domain_free(io_domain);
+}
+
+static int ipmmu_add_device_dma(struct device *dev)
+{
+ struct iommu_group *group;
+
+ /* only accept devices with iommus property */
+ if (of_count_phandle_with_args(dev->of_node, "iommus",
+ "#iommu-cells") < 0)
+ return -ENODEV;
+
+ group = iommu_group_get_for_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ return 0;
+}
+
+static void ipmmu_remove_device_dma(struct device *dev)
+{
+ iommu_group_remove_device(dev);
+}
+
+static struct iommu_group *ipmmu_device_group_dma(struct device *dev)
+{
+ struct iommu_group *group;
+ int ret;
+
+ group = generic_device_group(dev);
+ if (IS_ERR(group))
+ return group;
+
+ ret = ipmmu_init_platform_device(dev);
+ if (ret) {
+ iommu_group_put(group);
+ group = ERR_PTR(ret);
+ }
+
+ return group;
+}
+
+static int ipmmu_of_xlate_dma(struct device *dev,
+ struct of_phandle_args *spec)
+{
+ /* dummy callback to satisfy of_iommu_configure() */
+ return 0;
+}
+
+static const struct iommu_ops ipmmu_ops = {
+ .domain_alloc = ipmmu_domain_alloc_dma,
+ .domain_free = ipmmu_domain_free_dma,
+ .attach_dev = ipmmu_attach_device,
+ .detach_dev = ipmmu_detach_device,
+ .map = ipmmu_map,
+ .unmap = ipmmu_unmap,
+ .map_sg = default_iommu_map_sg,
+ .iova_to_phys = ipmmu_iova_to_phys,
+ .add_device = ipmmu_add_device_dma,
+ .remove_device = ipmmu_remove_device_dma,
+ .device_group = ipmmu_device_group_dma,
+ .pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
+ .of_xlate = ipmmu_of_xlate_dma,
+};
+
+#endif /* CONFIG_IOMMU_DMA */
+
/* -----------------------------------------------------------------------------
* Probe/remove and init
*/
@@ -910,7 +1003,9 @@ static int ipmmu_remove(struct platform_
list_del(&mmu->list);
spin_unlock(&ipmmu_devices_lock);

+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
arm_iommu_release_mapping(mmu->mapping);
+#endif

ipmmu_device_reset(mmu);