From: Magnus Damm <damm+rene...@opensource.se>
Extend the IPMMU driver to group devices together based
on the IPMMU device they are connected to. The slave
devices are kept on a list which is used to determine
if existing groups (and contexts) exist.
With this patch the two SYS-DMAC devices using IPMMU-DS0
on r8a7795 will be grouped together.
Signed-off-by: Magnus Damm <damm+rene...@opensource.se>
---
Changes since V1:
- New patch
drivers/iommu/ipmmu-vmsa.c | 68 ++++++++++++++++++++++++++++++++++++++------
1 file changed, 60 insertions(+), 8 deletions(-)
--- 0013/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c 2016-06-06 10:55:32.340607110 +0900
@@ -69,11 +69,16 @@ struct ipmmu_vmsa_archdata {
struct ipmmu_vmsa_device *mmu;
unsigned int *utlbs;
unsigned int num_utlbs;
+ struct device *dev;
+ struct list_head list;
};
static DEFINE_SPINLOCK(ipmmu_devices_lock);
static LIST_HEAD(ipmmu_devices);
+static DEFINE_SPINLOCK(ipmmu_slave_devices_lock);
+static LIST_HEAD(ipmmu_slave_devices);
+
static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom)
{
return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
@@ -619,6 +624,9 @@ static int ipmmu_attach_device(struct io
dev_err(dev, "Can't attach IPMMU %s to domain on IPMMU %s\n",
dev_name(mmu->dev), dev_name(domain->mmu->dev));
ret = -EINVAL;
+ } else {
+ dev_info(dev, "Reusing IPMMU context %u\n",
+ domain->context_id);
}
spin_unlock_irqrestore(&domain->lock, flags);
@@ -676,6 +684,42 @@ static phys_addr_t ipmmu_iova_to_phys(st
return domain->iop->iova_to_phys(domain->iop, iova);
}
+static struct device *ipmmu_find_sibling_device(struct device *dev)
+{
+ struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
+ struct ipmmu_vmsa_archdata *sibling_archdata = NULL;
+ bool found = false;
+
+ spin_lock(&ipmmu_slave_devices_lock);
+
+ list_for_each_entry(sibling_archdata, &ipmmu_slave_devices, list) {
+ if (archdata == sibling_archdata)
+ continue;
+ if (sibling_archdata->mmu == archdata->mmu) {
+ found = true;
+ break;
+ }
+ }
+
+ spin_unlock(&ipmmu_slave_devices_lock);
+
+ return found ? sibling_archdata->dev : NULL;
+}
+
+static struct iommu_group *ipmmu_find_group(struct device *dev)
+{
+ struct iommu_group *group;
+ struct device *sibling;
+
+ sibling = ipmmu_find_sibling_device(dev);
+ if (sibling)
+ group = iommu_group_get(sibling);
+ if (!sibling || IS_ERR(group))
+ group = generic_device_group(dev);
+
+ return group;
+}
+
static int ipmmu_find_utlbs(struct ipmmu_vmsa_device *mmu, struct device *dev,
unsigned int *utlbs, unsigned int num_utlbs)
{
@@ -756,6 +800,7 @@ static int ipmmu_init_platform_device(st
archdata->mmu = mmu;
archdata->utlbs = utlbs;
archdata->num_utlbs = num_utlbs;
+ archdata->dev = dev;
dev->archdata.iommu = archdata;
return 0;
@@ -908,6 +953,7 @@ static void ipmmu_domain_free_dma(struct
static int ipmmu_add_device_dma(struct device *dev)
{
+ struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
struct iommu_group *group;
/* only accept devices with iommus property */
@@ -919,11 +965,21 @@ static int ipmmu_add_device_dma(struct d
if (IS_ERR(group))
return PTR_ERR(group);
+ archdata = dev->archdata.iommu;
+ spin_lock(&ipmmu_slave_devices_lock);
+ list_add(&archdata->list, &ipmmu_slave_devices);
+ spin_unlock(&ipmmu_slave_devices_lock);
return 0;
}
static void ipmmu_remove_device_dma(struct device *dev)
{
+ struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
+
+ spin_lock(&ipmmu_slave_devices_lock);
+ list_del(&archdata->list);
+ spin_unlock(&ipmmu_slave_devices_lock);
+
iommu_group_remove_device(dev);
}
@@ -932,15 +988,11 @@ static struct iommu_group *ipmmu_device_
struct iommu_group *group;
int ret;
- group = generic_device_group(dev);
- if (IS_ERR(group))
- return group;
-
- ret = ipmmu_init_platform_device(dev, group);
- if (ret) {
- iommu_group_put(group);
+ ret = ipmmu_init_platform_device(dev, NULL);
+ if (!ret)
+ group = ipmmu_find_group(dev);
+ else
group = ERR_PTR(ret);
- }
return group;
}
