[PATCH v11 05/10] uacce: Enable IOMMU_DEV_FEAT_IOPF
From: Jean-Philippe Brucker <hidden>
Date: 2021-01-25 11:25:27
Also in:
linux-acpi, linux-devicetree, linux-iommu
Subsystem:
char and misc drivers, the rest, uacce accelerator framework · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds, Zhangfei Gao, Zhou Wang
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@linaro.org> Signed-off-by: Jean-Philippe Brucker <redacted> --- Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Zhangfei Gao <zhangfei.gao@linaro.org> Cc: Zhou Wang <wangzhou1@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);
--
2.30.0
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