qed*: Reduce the memory footprint for Rx path

With the current default values for Rx path i.e., 8 queues of 8Kb entries
each with 4Kb size, interface will consume 256Mb for Rx. The default values
causing the driver probe to fail when the system memory is low. Based on
the perforamnce results, rx-ring count value of 1Kb gives the comparable
performance with Rx coalesce timeout of 12 seconds. Updating the default
values.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/qlogic/qed/qed_main.c

@@ -878,6 +878,7 @@ static int qed_slowpath_start(struct qed_dev *cdev,
 		}
 	}
 
+	cdev->rx_coalesce_usecs = QED_DEFAULT_RX_USECS;
 	rc = qed_nic_setup(cdev);
 	if (rc)
 		goto err;

drivers/net/ethernet/qlogic/qede/qede.h

@@ -354,7 +354,7 @@ void qede_update_rx_prod(struct qede_dev *edev, struct qede_rx_queue *rxq);
 #define RX_RING_SIZE		((u16)BIT(RX_RING_SIZE_POW))
 #define NUM_RX_BDS_MAX		(RX_RING_SIZE - 1)
 #define NUM_RX_BDS_MIN		128
-#define NUM_RX_BDS_DEF		NUM_RX_BDS_MAX
+#define NUM_RX_BDS_DEF		((u16)BIT(10) - 1)
 
 #define TX_RING_SIZE_POW	13
 #define TX_RING_SIZE		((u16)BIT(TX_RING_SIZE_POW))

include/linux/qed/qed_if.h

@@ -146,6 +146,7 @@ enum qed_led_mode {
 #define DIRECT_REG_RD(reg_addr) readl((void __iomem *)(reg_addr))
 
 #define QED_COALESCE_MAX 0xFF
+#define QED_DEFAULT_RX_USECS 12
 
 /* forward */
 struct qed_dev;