Merge branch 'enetc-mqprio-fixes'

Wei Fang sayus:

====================
fix crash issue when setting MQPRIO for VFs

There is a crash issue when setting MQPRIO for ENETC VFs, the root casue
is that ENETC VFs don't like ENETC PFs, they don't have port registers,
so hw->port of VFs is NULL. However, this NULL pointer will be accessed
without any checks in enetc_mm_commit_preemptible_tcs() when configuring
MQPRIO for VFs. Therefore, two patches are added to fix this issue. The
first patch sets ENETC_SI_F_QBU flag only for SIs that support 802.1Qbu.
The second patch adds a check in enetc_change_preemptible_tcs() to ensure
that SIs that do not support 802.1Qbu do not configure preemptible TCs.

---
v1 Link: https://lore.kernel.org/imx/20241030082117.1172634-1-wei.fang@nxp.com/
v2 Link: https://lore.kernel.org/imx/20241104054309.1388433-1-wei.fang@nxp.com/
---
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 25 insertions, 12 deletions

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 35634c516e26..535969fa0fdb 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -29,6 +29,9 @@ EXPORT_SYMBOL_GPL(enetc_port_mac_wr);
 static void enetc_change_preemptible_tcs(struct enetc_ndev_priv *priv,
 					 u8 preemptible_tcs)
 {
+	if (!(priv->si->hw_features & ENETC_SI_F_QBU))
+		return;
+
 	priv->preemptible_tcs = preemptible_tcs;
 	enetc_mm_commit_preemptible_tcs(priv);
 }
@@ -1756,15 +1759,6 @@ void enetc_get_si_caps(struct enetc_si *si)
 		rss = enetc_rd(hw, ENETC_SIRSSCAPR);
 		si->num_rss = ENETC_SIRSSCAPR_GET_NUM_RSS(rss);
 	}
-
-	if (val & ENETC_SIPCAPR0_QBV)
-		si->hw_features |= ENETC_SI_F_QBV;
-
-	if (val & ENETC_SIPCAPR0_QBU)
-		si->hw_features |= ENETC_SI_F_QBU;
-
-	if (val & ENETC_SIPCAPR0_PSFP)
-		si->hw_features |= ENETC_SI_F_PSFP;
 }
 EXPORT_SYMBOL_GPL(enetc_get_si_caps);
 
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_hw.h b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
index 7c3285584f8a..55ba949230ff 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_hw.h
+++ b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
@@ -23,10 +23,7 @@
 #define ENETC_SICTR0	0x18
 #define ENETC_SICTR1	0x1c
 #define ENETC_SIPCAPR0	0x20
-#define ENETC_SIPCAPR0_PSFP	BIT(9)
 #define ENETC_SIPCAPR0_RSS	BIT(8)
-#define ENETC_SIPCAPR0_QBV	BIT(4)
-#define ENETC_SIPCAPR0_QBU	BIT(3)
 #define ENETC_SIPCAPR0_RFS	BIT(2)
 #define ENETC_SIPCAPR1	0x24
 #define ENETC_SITGTGR	0x30
@@ -194,6 +191,9 @@ enum enetc_bdr_type {TX, RX};
 #define ENETC_PCAPR0		0x0900
 #define ENETC_PCAPR0_RXBDR(val)	((val) >> 24)
 #define ENETC_PCAPR0_TXBDR(val)	(((val) >> 16) & 0xff)
+#define ENETC_PCAPR0_PSFP	BIT(9)
+#define ENETC_PCAPR0_QBV	BIT(4)
+#define ENETC_PCAPR0_QBU	BIT(3)
 #define ENETC_PCAPR1		0x0904
 #define ENETC_PSICFGR0(n)	(0x0940 + (n) * 0xc)  /* n = SI index */
 #define ENETC_PSICFGR0_SET_TXBDR(val)	((val) & 0xff)
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
index c47b4a743d93..203862ec1114 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
@@ -409,6 +409,23 @@ static void enetc_port_assign_rfs_entries(struct enetc_si *si)
 	enetc_port_wr(hw, ENETC_PRFSMR, ENETC_PRFSMR_RFSE);
 }
 
+static void enetc_port_get_caps(struct enetc_si *si)
+{
+	struct enetc_hw *hw = &si->hw;
+	u32 val;
+
+	val = enetc_port_rd(hw, ENETC_PCAPR0);
+
+	if (val & ENETC_PCAPR0_QBV)
+		si->hw_features |= ENETC_SI_F_QBV;
+
+	if (val & ENETC_PCAPR0_QBU)
+		si->hw_features |= ENETC_SI_F_QBU;
+
+	if (val & ENETC_PCAPR0_PSFP)
+		si->hw_features |= ENETC_SI_F_PSFP;
+}
+
 static void enetc_port_si_configure(struct enetc_si *si)
 {
 	struct enetc_pf *pf = enetc_si_priv(si);
@@ -416,6 +433,8 @@ static void enetc_port_si_configure(struct enetc_si *si)
 	int num_rings, i;
 	u32 val;
 
+	enetc_port_get_caps(si);
+
 	val = enetc_port_rd(hw, ENETC_PCAPR0);
 	num_rings = min(ENETC_PCAPR0_RXBDR(val), ENETC_PCAPR0_TXBDR(val));