[PATCH] bus/uacce: support no-iommu mode

[Chengwen Feng]

The uacce bus originally only supports devices with SVA capability.
This patch extends the uacce bus to support no-iommu mode for devices
without or not enabling IOMMU/SVA.

For no-iommu mode UACCE devices:
- The device api name is suffixed with _noiommu
- The device flags bit1 was set (UACCE_DEV_FLAG_NOIOMMU)

To support such devices, DPDK device drivers can mark
RTE_UACCE_DRV_SUPPORT_NOIOMMU_MODE in drv_flags to declare capability
of working with no-iommu devices.

This commit also fixes typo UACCE_DEV_FLGA_SVA -> UACCE_DEV_FLAG_SVA.

Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
---
 doc/guides/rel_notes/release_26_07.rst |  4 ++++
 drivers/bus/uacce/bus_uacce_driver.h   |  8 ++++++++
 drivers/bus/uacce/uacce.c              | 24 +++++++++++++++++-------
 3 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/doc/guides/rel_notes/release_26_07.rst b/doc/guides/rel_notes/release_26_07.rst
index f012d47a4b..1f53e1253e 100644
--- a/doc/guides/rel_notes/release_26_07.rst
+++ b/doc/guides/rel_notes/release_26_07.rst
@@ -63,6 +63,10 @@ New Features
     ``rte_eal_init`` and the application is responsible for probing each device,
   * ``--auto-probing`` enables the initial bus probing, which is the current default behavior.
 
+* **UACCE bus supports no-iommu mode.**
+
+  Support no-iommu mode for devices without or not enabling IOMMU/SVA.
+
 
 Removed Items
 -------------
diff --git a/drivers/bus/uacce/bus_uacce_driver.h b/drivers/bus/uacce/bus_uacce_driver.h
index c7445778a6..7ff9c7b483 100644
--- a/drivers/bus/uacce/bus_uacce_driver.h
+++ b/drivers/bus/uacce/bus_uacce_driver.h
@@ -15,6 +15,7 @@
 #include <stdlib.h>
 #include <linux/types.h>
 
+#include <rte_bitops.h>
 #include <rte_compat.h>
 #include <rte_devargs.h>
 #include <dev_driver.h>
@@ -28,6 +29,11 @@ extern "C" {
 #define RTE_UACCE_ALGS_NAME_SIZE	384
 #define RTE_UACCE_ATTR_MAX_SIZE		384
 
+/* UACCE device flag of SVA. */
+#define UACCE_DEV_FLAG_SVA	RTE_BIT32(0)
+/* UACCE device flag of NOIOMMU */
+#define UACCE_DEV_FLAG_NOIOMMU	RTE_BIT32(1)
+
 /*
  * Definition for queue file region type.
  */
@@ -106,6 +112,8 @@ struct rte_uacce_driver {
 
 /** Device driver supports forward compatibility device */
 #define RTE_UACCE_DRV_FORWARD_COMPATIBILITY_DEV	0x1
+/** Device driver supports NO-IOMMU mode */
+#define RTE_UACCE_DRV_SUPPORT_NOIOMMU_MODE	0x2
 
 /**
  * Get available queue number.
diff --git a/drivers/bus/uacce/uacce.c b/drivers/bus/uacce/uacce.c
index ade2452ad5..2dab3e1c4d 100644
--- a/drivers/bus/uacce/uacce.c
+++ b/drivers/bus/uacce/uacce.c
@@ -15,7 +15,6 @@
 #include <sys/types.h>
 
 #include <eal_export.h>
-#include <rte_bitops.h>
 #include <rte_common.h>
 #include <rte_devargs.h>
 #include <rte_eal_paging.h>
@@ -28,9 +27,6 @@
 
 #define UACCE_BUS_CLASS_PATH	"/sys/class/uacce"
 
-/* UACCE device flag of SVA. */
-#define UACCE_DEV_FLGA_SVA	RTE_BIT32(0)
-
 /* Support -a uacce:device-name when start DPDK application. */
 #define UACCE_DEV_PREFIX	"uacce:"
 
@@ -151,9 +147,19 @@ uacce_read_attr_u32(const char *dev_root, const char *attr, uint32_t *val)
 static int
 uacce_read_api(struct rte_uacce_device *dev)
 {
-	int ret = uacce_read_attr(dev->dev_root, "api", dev->api, sizeof(dev->api) - 1);
+#define NOIOMMU_SUBFIX		"_noiommu"
+	size_t api_len, sub_len;
+	int ret;
+
+	ret = uacce_read_attr(dev->dev_root, "api", dev->api, sizeof(dev->api) - 1);
 	if (ret < 0)
 		return ret;
+
+	api_len = strlen(dev->api);
+	sub_len = strlen(NOIOMMU_SUBFIX);
+	if (api_len > sub_len && strcmp(dev->api + api_len - sub_len, NOIOMMU_SUBFIX) == 0)
+		dev->api[api_len - sub_len] = 0;
+
 	return 0;
 }
 
@@ -196,8 +202,8 @@ uacce_read_qfrt_sz(struct rte_uacce_device *dev)
 static int
 uacce_verify(struct rte_uacce_device *dev)
 {
-	if (!(dev->flags & UACCE_DEV_FLGA_SVA)) {
-		UACCE_BUS_WARN("device %s don't support SVA, skip it!", dev->name);
+	if (!(dev->flags & (UACCE_DEV_FLAG_SVA | UACCE_DEV_FLAG_NOIOMMU))) {
+		UACCE_BUS_WARN("device %s don't support SVA or NOIOMMU, skip it!", dev->name);
 		return 1; /* >0 will skip this device. */
 	}
 
@@ -333,12 +339,16 @@ static bool
 uacce_match(const struct rte_uacce_driver *dr, struct rte_uacce_device *dev)
 {
 	bool forward_compat = !!(dr->drv_flags & RTE_UACCE_DRV_FORWARD_COMPATIBILITY_DEV);
+	bool support_noiommu = !!(dr->drv_flags & RTE_UACCE_DRV_SUPPORT_NOIOMMU_MODE);
 	uint32_t api_ver = uacce_calc_api_ver(dev->api, NULL);
 	const struct rte_uacce_id *id_table;
 	const char *map;
 	uint32_t len;
 
 	for (id_table = dr->id_table; id_table->dev_api != NULL; id_table++) {
+		if ((dev->flags & UACCE_DEV_FLAG_NOIOMMU) && !support_noiommu)
+			continue;
+
 		if (!uacce_match_api(dev, forward_compat, id_table))
 			continue;
 
-- 
2.17.1