[Intel-wired-lan] [PATCH net-next v2 11/13] ice: introduce clear_reset_state operation

[Jacob Keller <jacob.e.keller@intel.com>]

When hardware is reset, the VF relies on the VFGEN_RSTAT register to detect
when the VF is finished resetting. This is a tri-state register where 0
indicates a reset is in progress, 1 indicates the hardware is done
resetting, and 2 indicates that the software is done resetting.

Currently the PF driver relies on the device hardware resetting VFGEN_RSTAT
when a global reset occurs. This works ok, but it does mean that the VF
might not immediately notice a reset when the driver first detects that the
global reset is occurring.

This is also problematic for Scalable IOV, because there is no read/write
equivalent VFGEN_RSTAT register for the Scalable VSI type. Instead, the
Scalable IOV VFs will need to emulate this register.

To support this, introduce a new VF operation, clear_reset_state, which is
called when the PF driver first detects a global reset. The Single Root IOV
implementation can just write to VFGEN_RSTAT to ensure its cleared
immediately, without waiting for the actual hardware reset to begin. The
Scalable IOV implementation will use this as part of its tracking of the
reset status to allow properly reporting the emulated VFGEN_RSTAT to the VF
driver.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
Changes since v1:
* Add no-op version of  ice_set_vf_state_dis for when CONFIG_PCI_IOV is
  disabled.
* Make ice_set_state_qs_dis static since there are no callers outsice
  ice_vf_lib.c

 drivers/net/ethernet/intel/ice/ice_main.c   |  2 +-
 drivers/net/ethernet/intel/ice/ice_sriov.c  | 16 ++++++++++++++++
 drivers/net/ethernet/intel/ice/ice_vf_lib.c | 12 +++++++++++-
 drivers/net/ethernet/intel/ice/ice_vf_lib.h |  5 +++--
 4 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index 3b98721fd9d8..5d890b6aa9d2 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -537,7 +537,7 @@ ice_prepare_for_reset(struct ice_pf *pf, enum ice_reset_req reset_type)
 	/* Disable VFs until reset is completed */
 	mutex_lock(&pf->vfs.table_lock);
 	ice_for_each_vf(pf, bkt, vf)
-		ice_set_vf_state_qs_dis(vf);
+		ice_set_vf_state_dis(vf);
 	mutex_unlock(&pf->vfs.table_lock);
 
 	if (ice_is_eswitch_mode_switchdev(pf)) {
diff --git a/drivers/net/ethernet/intel/ice/ice_sriov.c b/drivers/net/ethernet/intel/ice/ice_sriov.c
index 46088c05d485..4d8930b83b35 100644
--- a/drivers/net/ethernet/intel/ice/ice_sriov.c
+++ b/drivers/net/ethernet/intel/ice/ice_sriov.c
@@ -654,6 +654,21 @@ static void ice_sriov_free_vf(struct ice_vf *vf)
 	kfree_rcu(vf, rcu);
 }
 
+/**
+ * ice_sriov_clear_reset_state - clears VF Reset status register
+ * @vf: the vf to configure
+ */
+static void ice_sriov_clear_reset_state(struct ice_vf *vf)
+{
+	struct ice_hw *hw = &vf->pf->hw;
+
+	/* Clear the reset status register so that VF immediately sees that
+	 * the device is resetting, even if hardware hasn't yet gotten around
+	 * to clearing VFGEN_RSTAT for us.
+	 */
+	wr32(hw, VFGEN_RSTAT(vf->vf_id), VIRTCHNL_VFR_INPROGRESS);
+}
+
 /**
  * ice_sriov_clear_mbx_register - clears SRIOV VF's mailbox registers
  * @vf: the vf to configure
@@ -787,6 +802,7 @@ static void ice_sriov_post_vsi_rebuild(struct ice_vf *vf)
 static const struct ice_vf_ops ice_sriov_vf_ops = {
 	.reset_type = ICE_VF_RESET,
 	.free = ice_sriov_free_vf,
+	.clear_reset_state = ice_sriov_clear_reset_state,
 	.clear_mbx_register = ice_sriov_clear_mbx_register,
 	.trigger_reset_register = ice_sriov_trigger_reset_register,
 	.poll_reset_status = ice_sriov_poll_reset_status,
diff --git a/drivers/net/ethernet/intel/ice/ice_vf_lib.c b/drivers/net/ethernet/intel/ice/ice_vf_lib.c
index 1a5d64454f99..2ea801ebb2ac 100644
--- a/drivers/net/ethernet/intel/ice/ice_vf_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_vf_lib.c
@@ -717,7 +717,7 @@ int ice_reset_vf(struct ice_vf *vf, u32 flags)
  * ice_set_vf_state_qs_dis - Set VF queues state to disabled
  * @vf: pointer to the VF structure
  */
-void ice_set_vf_state_qs_dis(struct ice_vf *vf)
+static void ice_set_vf_state_qs_dis(struct ice_vf *vf)
 {
 	/* Clear Rx/Tx enabled queues flag */
 	bitmap_zero(vf->txq_ena, ICE_MAX_RSS_QS_PER_VF);
@@ -725,6 +725,16 @@ void ice_set_vf_state_qs_dis(struct ice_vf *vf)
 	clear_bit(ICE_VF_STATE_QS_ENA, vf->vf_states);
 }
 
+/**
+ * ice_set_vf_state_dis - Set VF state to disabled
+ * @vf: pointer to the VF structure
+ */
+void ice_set_vf_state_dis(struct ice_vf *vf)
+{
+	ice_set_vf_state_qs_dis(vf);
+	vf->vf_ops->clear_reset_state(vf);
+}
+
 /* Private functions only accessed from other virtualization files */
 
 /**
diff --git a/drivers/net/ethernet/intel/ice/ice_vf_lib.h b/drivers/net/ethernet/intel/ice/ice_vf_lib.h
index e3d94f3ca40d..5bb75edb6cef 100644
--- a/drivers/net/ethernet/intel/ice/ice_vf_lib.h
+++ b/drivers/net/ethernet/intel/ice/ice_vf_lib.h
@@ -56,6 +56,7 @@ struct ice_mdd_vf_events {
 struct ice_vf_ops {
 	enum ice_disq_rst_src reset_type;
 	void (*free)(struct ice_vf *vf);
+	void (*clear_reset_state)(struct ice_vf *vf);
 	void (*clear_mbx_register)(struct ice_vf *vf);
 	void (*trigger_reset_register)(struct ice_vf *vf, bool is_vflr);
 	bool (*poll_reset_status)(struct ice_vf *vf);
@@ -213,7 +214,7 @@ u16 ice_get_num_vfs(struct ice_pf *pf);
 struct ice_vsi *ice_get_vf_vsi(struct ice_vf *vf);
 bool ice_is_vf_disabled(struct ice_vf *vf);
 int ice_check_vf_ready_for_cfg(struct ice_vf *vf);
-void ice_set_vf_state_qs_dis(struct ice_vf *vf);
+void ice_set_vf_state_dis(struct ice_vf *vf);
 bool ice_is_any_vf_in_unicast_promisc(struct ice_pf *pf);
 void
 ice_vf_get_promisc_masks(struct ice_vf *vf, struct ice_vsi *vsi,
@@ -259,7 +260,7 @@ static inline int ice_check_vf_ready_for_cfg(struct ice_vf *vf)
 	return -EOPNOTSUPP;
 }
 
-static inline void ice_set_vf_state_qs_dis(struct ice_vf *vf)
+static inline void ice_set_vf_state_dis(struct ice_vf *vf)
 {
 }
 
-- 
2.39.1.405.gd4c25cc71f83

_______________________________________________
Intel-wired-lan mailing list
Intel-wired-lan@osuosl.org
https://lists.osuosl.org/mailman/listinfo/intel-wired-lan