[dpdk-dev] [PATCH v3 3/6] ena: disable readless communication regarding to HW revision

[Jan Medala <jan@semihalf.com>]

Depending on HW revision readless communcation between host and device
may be unavailable.
In that case prevent PMD of seting up readless communication mechanism.

Signed-off-by: Alexander Matushevsky <matua@amazon.com>
Signed-off-by: Jakub Palider <jpa@semihalf.com>
Signed-off-by: Jan Medala <jan@semihalf.com>
---
 drivers/net/ena/ena_ethdev.c | 12 +++++++++++-
 drivers/net/ena/ena_ethdev.h |  2 ++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ena/ena_ethdev.c b/drivers/net/ena/ena_ethdev.c
index 62232a4..25637a6 100644
--- a/drivers/net/ena/ena_ethdev.c
+++ b/drivers/net/ena/ena_ethdev.c
@@ -338,7 +338,8 @@ static void ena_config_host_info(struct ena_com_dev *ena_dev)
 	host_info->driver_version =
 		(DRV_MODULE_VER_MAJOR) |
 		(DRV_MODULE_VER_MINOR << ENA_ADMIN_HOST_INFO_MINOR_SHIFT) |
-		(DRV_MODULE_VER_SUBMINOR << ENA_ADMIN_HOST_INFO_SUB_MINOR_SHIFT);
+		(DRV_MODULE_VER_SUBMINOR <<
+			ENA_ADMIN_HOST_INFO_SUB_MINOR_SHIFT);
 
 	rc = ena_com_set_host_attributes(ena_dev);
 	if (rc) {
@@ -1145,6 +1146,7 @@ static int ena_device_init(struct ena_com_dev *ena_dev,
 			   struct ena_com_dev_get_features_ctx *get_feat_ctx)
 {
 	int rc;
+	bool readless_supported;
 
 	/* Initialize mmio registers */
 	rc = ena_com_mmio_reg_read_request_init(ena_dev);
@@ -1153,6 +1155,14 @@ static int ena_device_init(struct ena_com_dev *ena_dev,
 		return rc;
 	}
 
+	/* The PCIe configuration space revision id indicate if mmio reg
+	 * read is disabled.
+	 */
+	readless_supported =
+		!(((struct rte_pci_device *)ena_dev->dmadev)->id.class_id
+			       & ENA_MMIO_DISABLE_REG_READ);
+	ena_com_set_mmio_read_mode(ena_dev, readless_supported);
+
 	/* reset device */
 	rc = ena_com_dev_reset(ena_dev);
 	if (rc) {
diff --git a/drivers/net/ena/ena_ethdev.h b/drivers/net/ena/ena_ethdev.h
index ab9667f..61390a9 100644
--- a/drivers/net/ena/ena_ethdev.h
+++ b/drivers/net/ena/ena_ethdev.h
@@ -54,6 +54,8 @@
 
 #define ENA_PKT_MAX_BUFS     17
 
+#define ENA_MMIO_DISABLE_REG_READ	BIT(0)
+
 #define	ENA_CIRC_COUNT(head, tail, size)				\
 	(((uint16_t)((uint16_t)(head) - (uint16_t)(tail))) & ((size) - 1))
 
-- 
2.8.2