bnxt_en: Update interrupt coalescing logic.

New firmware spec. allows interrupt coalescing parameters, such as
maximums, timer units, supported features to be queried.  Update
the driver to make use of the new call to query these parameters
and provide the legacy defaults if the call is not available.

Replace the hard-coded values with these parameters.
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -4944,46 +4944,113 @@ static int bnxt_hwrm_check_rings(struct bnxt *bp, int tx_rings, int rx_rings,
 					cp_rings, vnics);
 }
 
-static void bnxt_hwrm_set_coal_params(struct bnxt_coal *hw_coal,
+static void bnxt_hwrm_coal_params_qcaps(struct bnxt *bp)
+{
+	struct hwrm_ring_aggint_qcaps_output *resp = bp->hwrm_cmd_resp_addr;
+	struct bnxt_coal_cap *coal_cap = &bp->coal_cap;
+	struct hwrm_ring_aggint_qcaps_input req = {0};
+	int rc;
+
+	coal_cap->cmpl_params = BNXT_LEGACY_COAL_CMPL_PARAMS;
+	coal_cap->num_cmpl_dma_aggr_max = 63;
+	coal_cap->num_cmpl_dma_aggr_during_int_max = 63;
+	coal_cap->cmpl_aggr_dma_tmr_max = 65535;
+	coal_cap->cmpl_aggr_dma_tmr_during_int_max = 65535;
+	coal_cap->int_lat_tmr_min_max = 65535;
+	coal_cap->int_lat_tmr_max_max = 65535;
+	coal_cap->num_cmpl_aggr_int_max = 65535;
+	coal_cap->timer_units = 80;
+
+	if (bp->hwrm_spec_code < 0x10902)
+		return;
+
+	bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_RING_AGGINT_QCAPS, -1, -1);
+	mutex_lock(&bp->hwrm_cmd_lock);
+	rc = _hwrm_send_message_silent(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+	if (!rc) {
+		coal_cap->cmpl_params = le32_to_cpu(resp->cmpl_params);
+		coal_cap->num_cmpl_dma_aggr_max =
+			le16_to_cpu(resp->num_cmpl_dma_aggr_max);
+		coal_cap->num_cmpl_dma_aggr_during_int_max =
+			le16_to_cpu(resp->num_cmpl_dma_aggr_during_int_max);
+		coal_cap->cmpl_aggr_dma_tmr_max =
+			le16_to_cpu(resp->cmpl_aggr_dma_tmr_max);
+		coal_cap->cmpl_aggr_dma_tmr_during_int_max =
+			le16_to_cpu(resp->cmpl_aggr_dma_tmr_during_int_max);
+		coal_cap->int_lat_tmr_min_max =
+			le16_to_cpu(resp->int_lat_tmr_min_max);
+		coal_cap->int_lat_tmr_max_max =
+			le16_to_cpu(resp->int_lat_tmr_max_max);
+		coal_cap->num_cmpl_aggr_int_max =
+			le16_to_cpu(resp->num_cmpl_aggr_int_max);
+		coal_cap->timer_units = le16_to_cpu(resp->timer_units);
+	}
+	mutex_unlock(&bp->hwrm_cmd_lock);
+}
+
+static u16 bnxt_usec_to_coal_tmr(struct bnxt *bp, u16 usec)
+{
+	struct bnxt_coal_cap *coal_cap = &bp->coal_cap;
+
+	return usec * 1000 / coal_cap->timer_units;
+}
+
+static void bnxt_hwrm_set_coal_params(struct bnxt *bp,
+	struct bnxt_coal *hw_coal,
 	struct hwrm_ring_cmpl_ring_cfg_aggint_params_input *req)
 {
-	u16 val, tmr, max, flags;
+	struct bnxt_coal_cap *coal_cap = &bp->coal_cap;
+	u32 cmpl_params = coal_cap->cmpl_params;
+	u16 val, tmr, max, flags = 0;
 
 	max = hw_coal->bufs_per_record * 128;
 	if (hw_coal->budget)
 		max = hw_coal->bufs_per_record * hw_coal->budget;
+	max = min_t(u16, max, coal_cap->num_cmpl_aggr_int_max);
 
 	val = clamp_t(u16, hw_coal->coal_bufs, 1, max);
 	req->num_cmpl_aggr_int = cpu_to_le16(val);
 
-	/* This is a 6-bit value and must not be 0, or we'll get non stop IRQ */
-	val = min_t(u16, val, 63);
+	val = min_t(u16, val, coal_cap->num_cmpl_dma_aggr_max);
 	req->num_cmpl_dma_aggr = cpu_to_le16(val);
 
-	/* This is a 6-bit value and must not be 0, or we'll get non stop IRQ */
-	val = clamp_t(u16, hw_coal->coal_bufs_irq, 1, 63);
+	val = clamp_t(u16, hw_coal->coal_bufs_irq, 1,
+		      coal_cap->num_cmpl_dma_aggr_during_int_max);
 	req->num_cmpl_dma_aggr_during_int = cpu_to_le16(val);
 
-	tmr = BNXT_USEC_TO_COAL_TIMER(hw_coal->coal_ticks);
-	tmr = max_t(u16, tmr, 1);
+	tmr = bnxt_usec_to_coal_tmr(bp, hw_coal->coal_ticks);
+	tmr = clamp_t(u16, tmr, 1, coal_cap->int_lat_tmr_max_max);
 	req->int_lat_tmr_max = cpu_to_le16(tmr);
 
 	/* min timer set to 1/2 of interrupt timer */
-	val = tmr / 2;
-	req->int_lat_tmr_min = cpu_to_le16(val);
+	if (cmpl_params & RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_INT_LAT_TMR_MIN) {
+		val = tmr / 2;
+		val = clamp_t(u16, val, 1, coal_cap->int_lat_tmr_min_max);
+		req->int_lat_tmr_min = cpu_to_le16(val);
+		req->enables |= cpu_to_le16(BNXT_COAL_CMPL_MIN_TMR_ENABLE);
+	}
 
 	/* buf timer set to 1/4 of interrupt timer */
-	val = max_t(u16, tmr / 4, 1);
+	val = clamp_t(u16, tmr / 4, 1, coal_cap->cmpl_aggr_dma_tmr_max);
 	req->cmpl_aggr_dma_tmr = cpu_to_le16(val);
 
-	tmr = BNXT_USEC_TO_COAL_TIMER(hw_coal->coal_ticks_irq);
-	tmr = max_t(u16, tmr, 1);
-	req->cmpl_aggr_dma_tmr_during_int = cpu_to_le16(tmr);
+	if (cmpl_params &
+	    RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_NUM_CMPL_DMA_AGGR_DURING_INT) {
+		tmr = bnxt_usec_to_coal_tmr(bp, hw_coal->coal_ticks_irq);
+		val = clamp_t(u16, tmr, 1,
+			      coal_cap->cmpl_aggr_dma_tmr_during_int_max);
+		req->cmpl_aggr_dma_tmr_during_int = cpu_to_le16(tmr);
+		req->enables |=
+			cpu_to_le16(BNXT_COAL_CMPL_AGGR_TMR_DURING_INT_ENABLE);
+	}
 
-	flags = RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_FLAGS_TIMER_RESET;
-	if (hw_coal->idle_thresh && hw_coal->coal_ticks < hw_coal->idle_thresh)
+	if (cmpl_params & RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_TIMER_RESET)
+		flags |= RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_FLAGS_TIMER_RESET;
+	if ((cmpl_params & RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_RING_IDLE) &&
+	    hw_coal->idle_thresh && hw_coal->coal_ticks < hw_coal->idle_thresh)
 		flags |= RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_FLAGS_RING_IDLE;
 	req->flags = cpu_to_le16(flags);
+	req->enables |= cpu_to_le16(BNXT_COAL_CMPL_ENABLES);
 }
 
 int bnxt_hwrm_set_ring_coal(struct bnxt *bp, struct bnxt_napi *bnapi)
@@ -5007,7 +5074,7 @@ int bnxt_hwrm_set_ring_coal(struct bnxt *bp, struct bnxt_napi *bnapi)
 	bnxt_hwrm_cmd_hdr_init(bp, &req_rx,
 			       HWRM_RING_CMPL_RING_CFG_AGGINT_PARAMS, -1, -1);
 
-	bnxt_hwrm_set_coal_params(&coal, &req_rx);
+	bnxt_hwrm_set_coal_params(bp, &coal, &req_rx);
 
 	grp_idx = bnapi->index;
 	req_rx.ring_id = cpu_to_le16(bp->grp_info[grp_idx].cp_fw_ring_id);
@@ -5027,8 +5094,8 @@ int bnxt_hwrm_set_coal(struct bnxt *bp)
 	bnxt_hwrm_cmd_hdr_init(bp, &req_tx,
 			       HWRM_RING_CMPL_RING_CFG_AGGINT_PARAMS, -1, -1);
 
-	bnxt_hwrm_set_coal_params(&bp->rx_coal, &req_rx);
-	bnxt_hwrm_set_coal_params(&bp->tx_coal, &req_tx);
+	bnxt_hwrm_set_coal_params(bp, &bp->rx_coal, &req_rx);
+	bnxt_hwrm_set_coal_params(bp, &bp->tx_coal, &req_tx);
 
 	mutex_lock(&bp->hwrm_cmd_lock);
 	for (i = 0; i < bp->cp_nr_rings; i++) {
@@ -9075,6 +9142,8 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	bnxt_hwrm_set_cache_line_size(bp, cache_line_size());
 
+	bnxt_hwrm_coal_params_qcaps(bp);
+
 	if (BNXT_PF(bp)) {
 		if (!bnxt_pf_wq) {
 			bnxt_pf_wq =

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -631,6 +631,42 @@ struct bnxt_tx_ring_info {
 	struct bnxt_ring_struct	tx_ring_struct;
 };
 
+#define BNXT_LEGACY_COAL_CMPL_PARAMS					\
+	(RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_INT_LAT_TMR_MIN |		\
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_INT_LAT_TMR_MAX |		\
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_TIMER_RESET |		\
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_RING_IDLE |			\
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_NUM_CMPL_DMA_AGGR |		\
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_NUM_CMPL_DMA_AGGR_DURING_INT | \
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_CMPL_AGGR_DMA_TMR |		\
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_CMPL_AGGR_DMA_TMR_DURING_INT | \
+	 RING_AGGINT_QCAPS_RESP_CMPL_PARAMS_NUM_CMPL_AGGR_INT)
+
+#define BNXT_COAL_CMPL_ENABLES						\
+	(RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_ENABLES_NUM_CMPL_DMA_AGGR | \
+	 RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_ENABLES_CMPL_AGGR_DMA_TMR | \
+	 RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_ENABLES_INT_LAT_TMR_MAX | \
+	 RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_ENABLES_NUM_CMPL_AGGR_INT)
+
+#define BNXT_COAL_CMPL_MIN_TMR_ENABLE					\
+	RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_ENABLES_INT_LAT_TMR_MIN
+
+#define BNXT_COAL_CMPL_AGGR_TMR_DURING_INT_ENABLE			\
+	RING_CMPL_RING_CFG_AGGINT_PARAMS_REQ_ENABLES_NUM_CMPL_DMA_AGGR_DURING_INT
+
+struct bnxt_coal_cap {
+	u32			cmpl_params;
+	u32			nq_params;
+	u16			num_cmpl_dma_aggr_max;
+	u16			num_cmpl_dma_aggr_during_int_max;
+	u16			cmpl_aggr_dma_tmr_max;
+	u16			cmpl_aggr_dma_tmr_during_int_max;
+	u16			int_lat_tmr_min_max;
+	u16			int_lat_tmr_max_max;
+	u16			num_cmpl_aggr_int_max;
+	u16			timer_units;
+};
+
 struct bnxt_coal {
 	u16			coal_ticks;
 	u16			coal_ticks_irq;
@@ -1333,11 +1369,10 @@ struct bnxt {
 	u8			port_count;
 	u16			br_mode;
 
+	struct bnxt_coal_cap	coal_cap;
 	struct bnxt_coal	rx_coal;
 	struct bnxt_coal	tx_coal;
 
-#define BNXT_USEC_TO_COAL_TIMER(x)	((x) * 25 / 2)
-
 	u32			stats_coal_ticks;
 #define BNXT_DEF_STATS_COAL_TICKS	 1000000
 #define BNXT_MIN_STATS_COAL_TICKS	  250000