[PATCH 24/29] iommu: exynos: create default iommu-based dma-mapping for master devices

Marek Szyprowski
2014-08-05T10:51:00Z

This patch adds code to create default per-device iommu-based
dma-mapping instance for all master devices, whose driver didn't set
DRIVER_HAS_OWN_IOMMU_MANAGER flag.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
drivers/iommu/exynos-iommu.c | 49 +++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 48 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 845f547..336b2f8 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -12,6 +12,7 @@
#define DEBUG
#endif

+#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
@@ -29,6 +30,7 @@
#include <linux/export.h>

#include <asm/cacheflush.h>
+#include <asm/dma-iommu.h>
#include <asm/pgtable.h>

typedef u32 sysmmu_iova_t;
@@ -1064,6 +1066,43 @@ static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *domain,
return phys;
}

+static int sysmmu_master_device_event(struct notifier_block *nb,
+ unsigned long val, void *p)
+{
+ struct device *dev = p;
+ struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ struct sysmmu_drvdata *data;
+
+ if (!owner)
+ return 0;
+
+ data = list_first_entry(&owner->clients, struct sysmmu_drvdata,
+ owner_node);
+ if (!data)
+ return 0;
+
+ switch (val) {
+
+ case IOMMU_GROUP_NOTIFY_BIND_DRIVER:
+ if (!(dev->driver->flags & DRIVER_HAS_OWN_IOMMU_MANAGER))
+ arm_iommu_create_default_mapping(dev, data->base,
+ data->size);
+ break;
+
+ case IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER:
+ case IOMMU_GROUP_NOTIFY_DRVBIND_FAILED:
+ if (!(dev->driver->flags & DRIVER_HAS_OWN_IOMMU_MANAGER))
+ arm_iommu_release_default_mapping(dev);
+ break;
+ }
+
+ return 0;
+}
+
+static struct notifier_block sysmmu_master_device_notifier = {
+ .notifier_call = sysmmu_master_device_event,
+};
+
static void __free_owner_struct(struct exynos_iommu_owner *owner,
struct device *dev)
{
@@ -1202,6 +1241,7 @@ static int exynos_iommu_add_device(struct device *dev)
if (ret != 0)
goto err;

+ iommu_group_register_notifier(group, &sysmmu_master_device_notifier);
iommu_group_put(group);

return 0;
@@ -1213,8 +1253,15 @@ err:
static void exynos_iommu_remove_device(struct device *dev)
{
struct exynos_iommu_owner *owner = dev->archdata.iommu;
+ struct iommu_group *group = iommu_group_get(dev);
+
+ if (group) {
+ iommu_group_unregister_notifier(group,
+ &sysmmu_master_device_notifier);
+ iommu_group_remove_device(dev);
+ iommu_group_put(group);
+ }

- iommu_group_remove_device(dev);
if (owner)
__free_owner_struct(owner, dev);
}
--
1.9.2