[PATCH v14 05/10] uacce: Enable IOMMU_DEV_FEAT_IOPF
Jean-Philippe Brucker
jean-philippe at linaro.org
Thu Apr 1 16:47:14 BST 2021
The IOPF (I/O Page Fault) feature is now enabled independently from the
SVA feature, because some IOPF implementations are device-specific and
do not require IOMMU support for PCIe PRI or Arm SMMU stall.
Enable IOPF unconditionally when enabling SVA for now. In the future, if
a device driver implementing a uacce interface doesn't need IOPF
support, it will need to tell the uacce module, for example with a new
flag.
Acked-by: Zhangfei Gao <zhangfei.gao at linaro.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
Cc: Arnd Bergmann <arnd at arndb.de>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Cc: Zhangfei Gao <zhangfei.gao at linaro.org>
Cc: Zhou Wang <wangzhou1 at hisilicon.com>
---
drivers/misc/uacce/uacce.c | 39 +++++++++++++++++++++++++++++---------
1 file changed, 30 insertions(+), 9 deletions(-)
diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
index d07af4edfcac..6db7a98486ec 100644
--- a/drivers/misc/uacce/uacce.c
+++ b/drivers/misc/uacce/uacce.c
@@ -385,6 +385,33 @@ static void uacce_release(struct device *dev)
kfree(uacce);
}
+static unsigned int uacce_enable_sva(struct device *parent, unsigned int flags)
+{
+ if (!(flags & UACCE_DEV_SVA))
+ return flags;
+
+ flags &= ~UACCE_DEV_SVA;
+
+ if (iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_IOPF))
+ return flags;
+
+ if (iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA)) {
+ iommu_dev_disable_feature(parent, IOMMU_DEV_FEAT_IOPF);
+ return flags;
+ }
+
+ return flags | UACCE_DEV_SVA;
+}
+
+static void uacce_disable_sva(struct uacce_device *uacce)
+{
+ if (!(uacce->flags & UACCE_DEV_SVA))
+ return;
+
+ iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
+ iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_IOPF);
+}
+
/**
* uacce_alloc() - alloc an accelerator
* @parent: pointer of uacce parent device
@@ -404,11 +431,7 @@ struct uacce_device *uacce_alloc(struct device *parent,
if (!uacce)
return ERR_PTR(-ENOMEM);
- if (flags & UACCE_DEV_SVA) {
- ret = iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA);
- if (ret)
- flags &= ~UACCE_DEV_SVA;
- }
+ flags = uacce_enable_sva(parent, flags);
uacce->parent = parent;
uacce->flags = flags;
@@ -432,8 +455,7 @@ struct uacce_device *uacce_alloc(struct device *parent,
return uacce;
err_with_uacce:
- if (flags & UACCE_DEV_SVA)
- iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
+ uacce_disable_sva(uacce);
kfree(uacce);
return ERR_PTR(ret);
}
@@ -487,8 +509,7 @@ void uacce_remove(struct uacce_device *uacce)
mutex_unlock(&uacce->queues_lock);
/* disable sva now since no opened queues */
- if (uacce->flags & UACCE_DEV_SVA)
- iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
+ uacce_disable_sva(uacce);
if (uacce->cdev)
cdev_device_del(uacce->cdev, &uacce->dev);
--
2.31.1
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