[PATCH net-next 12/16] bnxt_en: Change IRQ assignment for RDMA driver.

[Michael Chan <michael.chan@broadcom.com>]

In the current code, the range of MSIX vectors allocated for the RDMA
driver is disjoint from the network driver.  This creates a problem
for the new firmware ring reservation scheme.  The new scheme requires
the reserved completion rings/MSIX vectors to be in a contiguous
range.

Change the logic to allocate RDMA MSIX vectors to be contiguous with
the vectors used by bnxt_en on new firmware using the new scheme.
The new function bnxt_get_num_msix() calculates the exact number of
vectors needed by both drivers.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     | 31 +++++++++++++++++++++++++--
 drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c | 30 +++++++++++++++++++++++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h |  3 +++
 3 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 8c8ef6b..041b800 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -4720,6 +4720,21 @@ static int bnxt_hwrm_reserve_rings(struct bnxt *bp, int tx, int rx, int grp,
 		return bnxt_hwrm_reserve_vf_rings(bp, tx, rx, grp, cp, vnic);
 }
 
+static int bnxt_cp_rings_in_use(struct bnxt *bp)
+{
+	int cp = bp->cp_nr_rings;
+	int ulp_msix, ulp_base;
+
+	ulp_msix = bnxt_get_ulp_msix_num(bp);
+	if (ulp_msix) {
+		ulp_base = bnxt_get_ulp_msix_base(bp);
+		cp += ulp_msix;
+		if ((ulp_base + ulp_msix) > cp)
+			cp = ulp_base + ulp_msix;
+	}
+	return cp;
+}
+
 static int bnxt_trim_rings(struct bnxt *bp, int *rx, int *tx, int max,
 			   bool shared);
 
@@ -5893,12 +5908,24 @@ void bnxt_set_max_func_irqs(struct bnxt *bp, unsigned int max_irqs)
 	bp->hw_resc.max_irqs = max_irqs;
 }
 
+static int bnxt_get_num_msix(struct bnxt *bp)
+{
+	if (!(bp->flags & BNXT_FLAG_NEW_RM))
+		return bnxt_get_max_func_irqs(bp);
+
+	return bnxt_cp_rings_in_use(bp);
+}
+
 static int bnxt_init_msix(struct bnxt *bp)
 {
-	int i, total_vecs, rc = 0, min = 1;
+	int i, total_vecs, max, rc = 0, min = 1;
 	struct msix_entry *msix_ent;
 
-	total_vecs = bnxt_get_max_func_irqs(bp);
+	total_vecs = bnxt_get_num_msix(bp);
+	max = bnxt_get_max_func_irqs(bp);
+	if (total_vecs > max)
+		total_vecs = max;
+
 	msix_ent = kcalloc(total_vecs, sizeof(struct msix_entry), GFP_KERNEL);
 	if (!msix_ent)
 		return -ENOMEM;
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
index 997e10e..62636cd 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
@@ -116,6 +116,9 @@ static int bnxt_req_msix_vecs(struct bnxt_en_dev *edev, int ulp_id,
 	if (!(bp->flags & BNXT_FLAG_USING_MSIX))
 		return -ENODEV;
 
+	if (edev->ulp_tbl[ulp_id].msix_requested)
+		return -EAGAIN;
+
 	max_cp_rings = bnxt_get_max_func_cp_rings(bp);
 	max_idx = min_t(int, bp->total_irqs, max_cp_rings);
 	avail_msix = max_idx - bp->cp_nr_rings;
@@ -124,7 +127,11 @@ static int bnxt_req_msix_vecs(struct bnxt_en_dev *edev, int ulp_id,
 	if (avail_msix > num_msix)
 		avail_msix = num_msix;
 
-	idx = max_idx - avail_msix;
+	if (bp->flags & BNXT_FLAG_NEW_RM)
+		idx = bp->cp_nr_rings;
+	else
+		idx = max_idx - avail_msix;
+	edev->ulp_tbl[ulp_id].msix_base = idx;
 	for (i = 0; i < avail_msix; i++) {
 		ent[i].vector = bp->irq_tbl[idx + i].vector;
 		ent[i].ring_idx = idx + i;
@@ -154,6 +161,27 @@ static int bnxt_free_msix_vecs(struct bnxt_en_dev *edev, int ulp_id)
 	return 0;
 }
 
+int bnxt_get_ulp_msix_num(struct bnxt *bp)
+{
+	if (bnxt_ulp_registered(bp->edev, BNXT_ROCE_ULP)) {
+		struct bnxt_en_dev *edev = bp->edev;
+
+		return edev->ulp_tbl[BNXT_ROCE_ULP].msix_requested;
+	}
+	return 0;
+}
+
+int bnxt_get_ulp_msix_base(struct bnxt *bp)
+{
+	if (bnxt_ulp_registered(bp->edev, BNXT_ROCE_ULP)) {
+		struct bnxt_en_dev *edev = bp->edev;
+
+		if (edev->ulp_tbl[BNXT_ROCE_ULP].msix_requested)
+			return edev->ulp_tbl[BNXT_ROCE_ULP].msix_base;
+	}
+	return 0;
+}
+
 void bnxt_subtract_ulp_resources(struct bnxt *bp, int ulp_id)
 {
 	ASSERT_RTNL();
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h
index d247106..c9fa7eb 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h
@@ -49,6 +49,7 @@ struct bnxt_ulp {
 	unsigned long	*async_events_bmap;
 	u16		max_async_event_id;
 	u16		msix_requested;
+	u16		msix_base;
 	atomic_t	ref_count;
 };
 
@@ -84,6 +85,8 @@ static inline bool bnxt_ulp_registered(struct bnxt_en_dev *edev, int ulp_id)
 	return false;
 }
 
+int bnxt_get_ulp_msix_num(struct bnxt *bp);
+int bnxt_get_ulp_msix_base(struct bnxt *bp);
 void bnxt_subtract_ulp_resources(struct bnxt *bp, int ulp_id);
 void bnxt_ulp_stop(struct bnxt *bp);
 void bnxt_ulp_start(struct bnxt *bp);
-- 
1.8.3.1