net: ena: add hardware hints capability to the driver

With this patch, ENA device can update the ena driver about
the desired timeout values:
These values are part of the "hardware hints" which are transmitted
to the driver as Asynchronous event through ENA async
event notification queue.

In case the ENA device does not support this capability,
the driver will use its own default values.

Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 32 insertions, 6 deletions

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index 02752d5b5b60..65d53d501139 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -511,7 +511,7 @@ static int ena_com_wait_and_process_admin_cq_polling(struct ena_comp_ctx *comp_c
 	unsigned long flags, timeout;
 	int ret;
 
-	timeout = jiffies + ADMIN_CMD_TIMEOUT_US;
+	timeout = jiffies + usecs_to_jiffies(admin_queue->completion_timeout);
 
 	while (1) {
 		spin_lock_irqsave(&admin_queue->q_lock, flags);
@@ -561,7 +561,8 @@ static int ena_com_wait_and_process_admin_cq_interrupts(struct ena_comp_ctx *com
 	int ret;
 
 	wait_for_completion_timeout(&comp_ctx->wait_event,
-				    usecs_to_jiffies(ADMIN_CMD_TIMEOUT_US));
+				    usecs_to_jiffies(
+					    admin_queue->completion_timeout));
 
 	/* In case the command wasn't completed find out the root cause.
 	 * There might be 2 kinds of errors
@@ -601,12 +602,15 @@ static u32 ena_com_reg_bar_read32(struct ena_com_dev *ena_dev, u16 offset)
 	struct ena_com_mmio_read *mmio_read = &ena_dev->mmio_read;
 	volatile struct ena_admin_ena_mmio_req_read_less_resp *read_resp =
 		mmio_read->read_resp;
-	u32 mmio_read_reg, ret;
+	u32 mmio_read_reg, ret, i;
 	unsigned long flags;
-	int i;
+	u32 timeout = mmio_read->reg_read_to;
 
 	might_sleep();
 
+	if (timeout == 0)
+		timeout = ENA_REG_READ_TIMEOUT;
+
 	/* If readless is disabled, perform regular read */
 	if (!mmio_read->readless_supported)
 		return readl(ena_dev->reg_bar + offset);
@@ -627,14 +631,14 @@ static u32 ena_com_reg_bar_read32(struct ena_com_dev *ena_dev, u16 offset)
 
 	writel(mmio_read_reg, ena_dev->reg_bar + ENA_REGS_MMIO_REG_READ_OFF);
 
-	for (i = 0; i < ENA_REG_READ_TIMEOUT; i++) {
+	for (i = 0; i < timeout; i++) {
 		if (read_resp->req_id == mmio_read->seq_num)
 			break;
 
 		udelay(1);
 	}
 
-	if (unlikely(i == ENA_REG_READ_TIMEOUT)) {
+	if (unlikely(i == timeout)) {
 		pr_err("reading reg failed for timeout. expected: req id[%hu] offset[%hu] actual: req id[%hu] offset[%hu]\n",
 		       mmio_read->seq_num, offset, read_resp->req_id,
 		       read_resp->reg_off);
@@ -1730,6 +1734,20 @@ int ena_com_get_dev_attr_feat(struct ena_com_dev *ena_dev,
 	memcpy(&get_feat_ctx->offload, &get_resp.u.offload,
 	       sizeof(get_resp.u.offload));
 
+	/* Driver hints isn't mandatory admin command. So in case the
+	 * command isn't supported set driver hints to 0
+	 */
+	rc = ena_com_get_feature(ena_dev, &get_resp, ENA_ADMIN_HW_HINTS);
+
+	if (!rc)
+		memcpy(&get_feat_ctx->hw_hints, &get_resp.u.hw_hints,
+		       sizeof(get_resp.u.hw_hints));
+	else if (rc == -EOPNOTSUPP)
+		memset(&get_feat_ctx->hw_hints, 0x0,
+		       sizeof(get_feat_ctx->hw_hints));
+	else
+		return rc;
+
 	return 0;
 }
 
@@ -1855,6 +1873,14 @@ int ena_com_dev_reset(struct ena_com_dev *ena_dev)
 		return rc;
 	}
 
+	timeout = (cap & ENA_REGS_CAPS_ADMIN_CMD_TO_MASK) >>
+		ENA_REGS_CAPS_ADMIN_CMD_TO_SHIFT;
+	if (timeout)
+		/* the resolution of timeout reg is 100ms */
+		ena_dev->admin_queue.completion_timeout = timeout * 100000;
+	else
+		ena_dev->admin_queue.completion_timeout = ADMIN_CMD_TIMEOUT_US;
+
 	return 0;
 }