ionic: support longer tx sg lists

The version 1 Tx queues can use longer SG lists than the
original version 0 queues, but we need to check to see if the
firmware supports the v1 Tx queues.  This implements the queue
type query for all queue types, and uses the information to
set up for using the longer Tx SG lists.

Because the Tx SG list can be longer, we need to limit the
max ring length to be sure we stay inside the boundaries of a
DMA allocation max size, so we lower the max Tx ring size.

The driver sets its highest known version in the Q_IDENTITY
command, and the FW returns the highest version that it knows,
bounded by the driver's version.  The negotiated version number
is later used in the Q_INIT commands.

Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 97 insertions, 15 deletions

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_if.h b/drivers/net/ethernet/pensando/ionic/ionic_if.h
index ceeb7629e7a0..799f3ea599e9 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_if.h
+++ b/drivers/net/ethernet/pensando/ionic/ionic_if.h
@@ -40,6 +40,7 @@ enum ionic_cmd_opcode {
 	IONIC_CMD_RX_FILTER_DEL			= 32,
 
 	/* Queue commands */
+	IONIC_CMD_Q_IDENTIFY			= 39,
 	IONIC_CMD_Q_INIT			= 40,
 	IONIC_CMD_Q_CONTROL			= 41,
 
@@ -469,6 +470,66 @@ struct ionic_lif_init_comp {
 	u8 rsvd2[12];
 };
 
+ /**
+  * struct ionic_q_identify_cmd - queue identify command
+  * @opcode:     opcode
+  * @lif_type:   LIF type (enum ionic_lif_type)
+  * @type:       Logical queue type (enum ionic_logical_qtype)
+  * @ver:        Highest queue type version that the driver supports
+  */
+struct ionic_q_identify_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 lif_type;
+	u8     type;
+	u8     ver;
+	u8     rsvd2[58];
+};
+
+/**
+ * struct ionic_q_identify_comp - queue identify command completion
+ * @status:     Status of the command (enum ionic_status_code)
+ * @comp_index: Index in the descriptor ring for which this is the completion
+ * @ver:        Queue type version that can be used with FW
+ */
+struct ionic_q_identify_comp {
+	u8     status;
+	u8     rsvd;
+	__le16 comp_index;
+	u8     ver;
+	u8     rsvd2[11];
+};
+
+/**
+ * union ionic_q_identity - queue identity information
+ *     @version:        Queue type version that can be used with FW
+ *     @supported:      Bitfield of queue versions, first bit = ver 0
+ *     @features:       Queue features
+ *     @desc_sz:        Descriptor size
+ *     @comp_sz:        Completion descriptor size
+ *     @sg_desc_sz:     Scatter/Gather descriptor size
+ *     @max_sg_elems:   Maximum number of Scatter/Gather elements
+ *     @sg_desc_stride: Number of Scatter/Gather elements per descriptor
+ */
+union ionic_q_identity {
+	struct {
+		u8      version;
+		u8      supported;
+		u8      rsvd[6];
+#define IONIC_QIDENT_F_CQ	0x01	/* queue has completion ring */
+#define IONIC_QIDENT_F_SG	0x02	/* queue has scatter/gather ring */
+#define IONIC_QIDENT_F_EQ	0x04	/* queue can use event queue */
+#define IONIC_QIDENT_F_CMB	0x08	/* queue is in cmb bar */
+		__le64  features;
+		__le16  desc_sz;
+		__le16  comp_sz;
+		__le16  sg_desc_sz;
+		__le16  max_sg_elems;
+		__le16  sg_desc_stride;
+	};
+	__le32 words[478];
+};
+
 /**
  * struct ionic_q_init_cmd - Queue init command
  * @opcode:       opcode
@@ -733,20 +794,31 @@ static inline void decode_txq_desc_cmd(u64 cmd, u8 *opcode, u8 *flags,
 	*addr = (cmd >> IONIC_TXQ_DESC_ADDR_SHIFT) & IONIC_TXQ_DESC_ADDR_MASK;
 };
 
-#define IONIC_TX_MAX_SG_ELEMS	8
-#define IONIC_RX_MAX_SG_ELEMS	8
-
 /**
- * struct ionic_txq_sg_desc - Transmit scatter-gather (SG) list
+ * struct ionic_txq_sg_elem - Transmit scatter-gather (SG) descriptor element
  * @addr:      DMA address of SG element data buffer
  * @len:       Length of SG element data buffer, in bytes
  */
+struct ionic_txq_sg_elem {
+	__le64 addr;
+	__le16 len;
+	__le16 rsvd[3];
+};
+
+/**
+ * struct ionic_txq_sg_desc - Transmit scatter-gather (SG) list
+ * @elems:     Scatter-gather elements
+ */
 struct ionic_txq_sg_desc {
-	struct ionic_txq_sg_elem {
-		__le64 addr;
-		__le16 len;
-		__le16 rsvd[3];
-	} elems[IONIC_TX_MAX_SG_ELEMS];
+#define IONIC_TX_MAX_SG_ELEMS		8
+#define IONIC_TX_SG_DESC_STRIDE		8
+	struct ionic_txq_sg_elem elems[IONIC_TX_MAX_SG_ELEMS];
+};
+
+struct ionic_txq_sg_desc_v1 {
+#define IONIC_TX_MAX_SG_ELEMS_V1		15
+#define IONIC_TX_SG_DESC_STRIDE_V1		16
+	struct ionic_txq_sg_elem elems[IONIC_TX_SG_DESC_STRIDE_V1];
 };
 
 /**
@@ -791,16 +863,24 @@ struct ionic_rxq_desc {
 };
 
 /**
- * struct ionic_rxq_sg_desc - Receive scatter-gather (SG) list
+ * struct ionic_rxq_sg_desc - Receive scatter-gather (SG) descriptor element
  * @addr:      DMA address of SG element data buffer
  * @len:       Length of SG element data buffer, in bytes
  */
+struct ionic_rxq_sg_elem {
+	__le64 addr;
+	__le16 len;
+	__le16 rsvd[3];
+};
+
+/**
+ * struct ionic_rxq_sg_desc - Receive scatter-gather (SG) list
+ * @elems:     Scatter-gather elements
+ */
 struct ionic_rxq_sg_desc {
-	struct ionic_rxq_sg_elem {
-		__le64 addr;
-		__le16 len;
-		__le16 rsvd[3];
-	} elems[IONIC_RX_MAX_SG_ELEMS];
+#define IONIC_RX_MAX_SG_ELEMS		8
+#define IONIC_RX_SG_DESC_STRIDE		8
+	struct ionic_rxq_sg_elem elems[IONIC_RX_SG_DESC_STRIDE];
 };
 
 /**
@@ -2389,6 +2469,7 @@ union ionic_dev_cmd {
 	struct ionic_qos_init_cmd qos_init;
 	struct ionic_qos_reset_cmd qos_reset;
 
+	struct ionic_q_identify_cmd q_identify;
 	struct ionic_q_init_cmd q_init;
 };
 
@@ -2421,6 +2502,7 @@ union ionic_dev_cmd_comp {
 	ionic_qos_init_comp qos_init;
 	ionic_qos_reset_comp qos_reset;
 
+	struct ionic_q_identify_comp q_identify;
 	struct ionic_q_init_comp q_init;
 };