bnxt_en: Re-enable SR-IOV after firmware reset

When the firmware undergoes a hot-reset and the driver re-opens the
device, previously active Virtual Functions lose their resource
configuration.  bnxt_reenable_sriov() restores that configuration by
replaying bnxt_cfg_hw_sriov() with the saved resource parameters.

The function is called from bnxt_fw_reset_task() in the
BNXT_FW_RESET_STATE_OPENING state, guarded by #ifdef PCI_IOV.
Because bnxt_cfg_hw_sriov() is a no-op when active_vfs is zero the
call is safe on any PF regardless of whether VFs were ever created.

MFC after:      1 month
Reviewed by:    ssaxena
Differential Revision: https://reviews.freebsd.org/D56201

2 files changed, 13 insertions, 0 deletions

diff --git a/sys/dev/bnxt/bnxt_en/bnxt_sriov.c b/sys/dev/bnxt/bnxt_en/bnxt_sriov.c
index 2d9b43728c2d..2aeefd9308fb 100644
--- a/sys/dev/bnxt/bnxt_en/bnxt_sriov.c
+++ b/sys/dev/bnxt/bnxt_en/bnxt_sriov.c
@@ -972,3 +972,13 @@ void bnxt_sriov_attach(struct bnxt_softc *softc)
 		device_printf(dev, "Failed to initialize SR-IOV (error=%d)\n", rc);
 }
 
+void bnxt_reenable_sriov(struct bnxt_softc *bp)
+{
+	if (BNXT_PF(bp)) {
+		struct bnxt_pf_info *pf = &bp->pf;
+		uint16_t n = pf->active_vfs;
+
+		if (n)
+			bnxt_cfg_hw_sriov(bp, &n, true);
+	}
+}
diff --git a/sys/dev/bnxt/bnxt_en/if_bnxt.c b/sys/dev/bnxt/bnxt_en/if_bnxt.c
index 8023ee1524c5..b48c28f002d8 100644
--- a/sys/dev/bnxt/bnxt_en/if_bnxt.c
+++ b/sys/dev/bnxt/bnxt_en/if_bnxt.c
@@ -2327,6 +2327,9 @@ static void bnxt_fw_reset_task(struct work_struct *work)
 		bnxt_ulp_start(bp, 0);
 		clear_bit(BNXT_STATE_FW_ACTIVATE, &bp->state);
 		set_bit(BNXT_STATE_OPEN, &bp->state);
+#ifdef PCI_IOV
+		bnxt_reenable_sriov(bp);
+#endif
 		rtnl_unlock();
 	}
 	return;