crypto: hisilicon/sec2 - Add iommu status check

In order to improve performance of small packets (<512Bytes)
in SMMU translation scenario, we need to identify the type of IOMMU
in the SEC probe to process small packets by a different method.
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Signed-off-by: Zaibo Xu <xuzaibo@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/hisilicon/sec2/sec.h

@@ -165,6 +165,7 @@ struct sec_dev {
 	struct list_head list;
 	struct sec_debug debug;
 	u32 ctx_q_num;
+	bool iommu_used;
 	u32 num_vfs;
 	unsigned long status;
 };

drivers/crypto/hisilicon/sec2/sec_main.c

@@ -7,6 +7,7 @@
 #include <linux/debugfs.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/iommu.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -832,6 +833,23 @@ static void sec_probe_uninit(struct hisi_qm *qm)
 	destroy_workqueue(qm->wq);
 }
 
+static void sec_iommu_used_check(struct sec_dev *sec)
+{
+	struct iommu_domain *domain;
+	struct device *dev = &sec->qm.pdev->dev;
+
+	domain = iommu_get_domain_for_dev(dev);
+
+	/* Check if iommu is used */
+	sec->iommu_used = false;
+	if (domain) {
+		if (domain->type & __IOMMU_DOMAIN_PAGING)
+			sec->iommu_used = true;
+		dev_info(dev, "SMMU Opened, the iommu type = %u\n",
+			domain->type);
+	}
+}
+
 static int sec_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	struct sec_dev *sec;
@@ -845,6 +863,7 @@ static int sec_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	pci_set_drvdata(pdev, sec);
 
 	sec->ctx_q_num = ctx_q_num;
+	sec_iommu_used_check(sec);
 
 	qm = &sec->qm;