[PATCH 5.4.y 1/2] i40e: increase max descriptors for XL710

[Sasha Levin <sashal@kernel.org>]

From: Justin Bronder <jsbronder@cold-front.org>

[ Upstream commit aa6908ca3bd1e713fd6cd8d7193a008f060bf7d9 ]

In Tables 8-12 and 8-22 in the X710/XXV710/XL710 datasheet, the QLEN
description states that the maximum size of the descriptor queue is 8k
minus 32, or 8160.

Signed-off-by: Justin Bronder <jsbronder@cold-front.org>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20231113231047.548659-2-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 55d225670def ("i40e: add validation for ring_len param")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/intel/i40e/i40e.h        |  1 +
 .../net/ethernet/intel/i40e/i40e_ethtool.c    | 25 ++++++++++++++-----
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index edb5e408c980f..1622573ffe37a 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -48,6 +48,7 @@
 #define I40E_MAX_VEB			16
 
 #define I40E_MAX_NUM_DESCRIPTORS	4096
+#define I40E_MAX_NUM_DESCRIPTORS_XL710	8160
 #define I40E_MAX_CSR_SPACE		(4 * 1024 * 1024 - 64 * 1024)
 #define I40E_DEFAULT_NUM_DESCRIPTORS	512
 #define I40E_REQ_DESCRIPTOR_MULTIPLE	32
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index 95a6f8689b6f1..4c42c8b0e8936 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -1914,6 +1914,18 @@ static void i40e_get_drvinfo(struct net_device *netdev,
 		drvinfo->n_priv_flags += I40E_GL_PRIV_FLAGS_STR_LEN;
 }
 
+static u32 i40e_get_max_num_descriptors(struct i40e_pf *pf)
+{
+	struct i40e_hw *hw = &pf->hw;
+
+	switch (hw->mac.type) {
+	case I40E_MAC_XL710:
+		return I40E_MAX_NUM_DESCRIPTORS_XL710;
+	default:
+		return I40E_MAX_NUM_DESCRIPTORS;
+	}
+}
+
 static void i40e_get_ringparam(struct net_device *netdev,
 			       struct ethtool_ringparam *ring)
 {
@@ -1921,8 +1933,8 @@ static void i40e_get_ringparam(struct net_device *netdev,
 	struct i40e_pf *pf = np->vsi->back;
 	struct i40e_vsi *vsi = pf->vsi[pf->lan_vsi];
 
-	ring->rx_max_pending = I40E_MAX_NUM_DESCRIPTORS;
-	ring->tx_max_pending = I40E_MAX_NUM_DESCRIPTORS;
+	ring->rx_max_pending = i40e_get_max_num_descriptors(pf);
+	ring->tx_max_pending = i40e_get_max_num_descriptors(pf);
 	ring->rx_mini_max_pending = 0;
 	ring->rx_jumbo_max_pending = 0;
 	ring->rx_pending = vsi->rx_rings[0]->count;
@@ -1945,12 +1957,12 @@ static bool i40e_active_tx_ring_index(struct i40e_vsi *vsi, u16 index)
 static int i40e_set_ringparam(struct net_device *netdev,
 			      struct ethtool_ringparam *ring)
 {
+	u32 new_rx_count, new_tx_count, max_num_descriptors;
 	struct i40e_ring *tx_rings = NULL, *rx_rings = NULL;
 	struct i40e_netdev_priv *np = netdev_priv(netdev);
 	struct i40e_hw *hw = &np->vsi->back->hw;
 	struct i40e_vsi *vsi = np->vsi;
 	struct i40e_pf *pf = vsi->back;
-	u32 new_rx_count, new_tx_count;
 	u16 tx_alloc_queue_pairs;
 	int timeout = 50;
 	int i, err = 0;
@@ -1958,14 +1970,15 @@ static int i40e_set_ringparam(struct net_device *netdev,
 	if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
 		return -EINVAL;
 
-	if (ring->tx_pending > I40E_MAX_NUM_DESCRIPTORS ||
+	max_num_descriptors = i40e_get_max_num_descriptors(pf);
+	if (ring->tx_pending > max_num_descriptors ||
 	    ring->tx_pending < I40E_MIN_NUM_DESCRIPTORS ||
-	    ring->rx_pending > I40E_MAX_NUM_DESCRIPTORS ||
+	    ring->rx_pending > max_num_descriptors ||
 	    ring->rx_pending < I40E_MIN_NUM_DESCRIPTORS) {
 		netdev_info(netdev,
 			    "Descriptors requested (Tx: %d / Rx: %d) out of range [%d-%d]\n",
 			    ring->tx_pending, ring->rx_pending,
-			    I40E_MIN_NUM_DESCRIPTORS, I40E_MAX_NUM_DESCRIPTORS);
+			    I40E_MIN_NUM_DESCRIPTORS, max_num_descriptors);
 		return -EINVAL;
 	}
 
-- 
2.51.0