[PATCH v2 09/13] iommu/rockchip: Use iommu_group_get_for_dev() for add_device

Jeffy Chen
2018-01-16T13:25:36Z

IOMMU drivers are supposed to call this function instead of manually
creating a group in their .add_device callback. This behavior is not
strictly required by ARM DMA mapping implementation, but ARM64 already
relies on it. This patch fixes the rockchip-iommu driver to comply with
this requirement.

Signed-off-by: Tomasz Figa <tfiga-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Signed-off-by: Jeffy Chen <jeffy.chen-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---

Changes in v2: None

drivers/iommu/rockchip-iommu.c | 120 +++++++++++++++++++++--------------------
1 file changed, 63 insertions(+), 57 deletions(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index a7442d59ca43..ea4df162108b 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -888,6 +888,39 @@ static struct rk_iommu *rk_iommu_from_dev(struct device *dev)
return rk_iommu;
}

+static void rk_iommu_detach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct rk_iommu *iommu;
+ struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
+ unsigned long flags;
+ int i;
+
+ /* Allow 'virtual devices' (eg drm) to detach from domain */
+ iommu = rk_iommu_from_dev(dev);
+ if (!iommu)
+ return;
+
+ spin_lock_irqsave(&rk_domain->iommus_lock, flags);
+ list_del_init(&iommu->node);
+ spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
+
+ /* Ignore error while disabling, just keep going */
+ WARN_ON(rk_iommu_enable_clocks(iommu));
+ rk_iommu_enable_stall(iommu);
+ rk_iommu_disable_paging(iommu);
+ for (i = 0; i < iommu->num_mmu; i++) {
+ rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, 0);
+ rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, 0);
+ }
+ rk_iommu_disable_stall(iommu);
+ rk_iommu_disable_clocks(iommu);
+
+ iommu->domain = NULL;
+
+ dev_dbg(dev, "Detached from iommu domain\n");
+}
+
static int rk_iommu_attach_device(struct iommu_domain *domain,
struct device *dev)
{
@@ -904,6 +937,9 @@ static int rk_iommu_attach_device(struct iommu_domain *domain,
if (!iommu)
return 0;

+ if (iommu->domain)
+ rk_iommu_detach_device(iommu->domain, dev);
+
ret = rk_iommu_enable_clocks(iommu);
if (ret)
return ret;
@@ -948,39 +984,6 @@ static int rk_iommu_attach_device(struct iommu_domain *domain,
return ret;
}

-static void rk_iommu_detach_device(struct iommu_domain *domain,
- struct device *dev)
-{
- struct rk_iommu *iommu;
- struct rk_iommu_domain *rk_domain = to_rk_domain(domain);
- unsigned long flags;
- int i;
-
- /* Allow 'virtual devices' (eg drm) to detach from domain */
- iommu = rk_iommu_from_dev(dev);
- if (!iommu)
- return;
-
- spin_lock_irqsave(&rk_domain->iommus_lock, flags);
- list_del_init(&iommu->node);
- spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
-
- /* Ignore error while disabling, just keep going */
- WARN_ON(rk_iommu_enable_clocks(iommu));
- rk_iommu_enable_stall(iommu);
- rk_iommu_disable_paging(iommu);
- for (i = 0; i < iommu->num_mmu; i++) {
- rk_iommu_write(iommu->bases[i], RK_MMU_INT_MASK, 0);
- rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR, 0);
- }
- rk_iommu_disable_stall(iommu);
- rk_iommu_disable_clocks(iommu);
-
- iommu->domain = NULL;
-
- dev_dbg(dev, "Detached from iommu domain\n");
-}
-
static struct iommu_domain *rk_iommu_domain_alloc(unsigned type)
{
struct rk_iommu_domain *rk_domain;
@@ -1131,41 +1134,20 @@ static int rk_iommu_add_device(struct device *dev)
{
struct iommu_group *group;
struct rk_iommu *iommu;
- int ret;

if (!rk_iommu_is_dev_iommu_master(dev))
return -ENODEV;

- group = iommu_group_get(dev);
- if (!group) {
- group = iommu_group_alloc();
- if (IS_ERR(group)) {
- dev_err(dev, "Failed to allocate IOMMU group\n");
- return PTR_ERR(group);
- }
- }
-
- ret = iommu_group_add_device(group, dev);
- if (ret)
- goto err_put_group;
-
- ret = rk_iommu_group_set_iommudata(group, dev);
- if (ret)
- goto err_remove_device;
+ group = iommu_group_get_for_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);

iommu = rk_iommu_from_dev(dev);
if (iommu)
iommu_device_link(&iommu->iommu, dev);

iommu_group_put(group);
-
return 0;
-
-err_remove_device:
- iommu_group_remove_device(dev);
-err_put_group:
- iommu_group_put(group);
- return ret;
}

static void rk_iommu_remove_device(struct device *dev)
@@ -1182,6 +1164,29 @@ static void rk_iommu_remove_device(struct device *dev)
iommu_group_remove_device(dev);
}

+static struct iommu_group *rk_iommu_device_group(struct device *dev)
+{
+ struct iommu_group *group;
+ int ret;
+
+ group = iommu_group_get(dev);
+ if (!group) {
+ group = iommu_group_alloc();
+ if (IS_ERR(group))
+ return group;
+ }
+
+ ret = rk_iommu_group_set_iommudata(group, dev);
+ if (ret)
+ goto err_put_group;
+
+ return group;
+
+err_put_group:
+ iommu_group_put(group);
+ return ERR_PTR(ret);
+}
+
static const struct iommu_ops rk_iommu_ops = {
.domain_alloc = rk_iommu_domain_alloc,
.domain_free = rk_iommu_domain_free,
@@ -1193,6 +1198,7 @@ static const struct iommu_ops rk_iommu_ops = {
.add_device = rk_iommu_add_device,
.remove_device = rk_iommu_remove_device,
.iova_to_phys = rk_iommu_iova_to_phys,
+ .device_group = rk_iommu_device_group,
.pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP,
};

--
2.11.0