Add support for speed in mana ethtool get_link_ksettings
operation. This feature is not supported by all hardware.

Signed-off-by: Erni Sri Satya Vennela <ernis@linux.microsoft.com>
Reviewed-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
---
Changes in v2:
* Use -EOPNOTSUPP instead of -EPROTO in mana_query_link_cfg().
---
 drivers/net/ethernet/microsoft/mana/mana_en.c | 42 +++++++++++++++++++
 .../ethernet/microsoft/mana/mana_ethtool.c    |  6 +++
 include/net/mana/mana.h                       | 17 ++++++++
 3 files changed, 65 insertions(+)

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 2bac6be8f6a0..ba550fc7ece0 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -1156,6 +1156,48 @@ static int mana_cfg_vport_steering(struct mana_port_context *apc,
 	return err;
 }
 
+int mana_query_link_cfg(struct mana_port_context *apc)
+{
+	struct net_device *ndev = apc->ndev;
+	struct mana_query_link_config_resp resp = {};
+	struct mana_query_link_config_req req = {};
+	int err;
+
+	mana_gd_init_req_hdr(&req.hdr, MANA_QUERY_LINK_CONFIG,
+			     sizeof(req), sizeof(resp));
+
+	req.vport = apc->port_handle;
+
+	err = mana_send_request(apc->ac, &req, sizeof(req), &resp,
+				sizeof(resp));
+
+	if (err) {
+		netdev_err(ndev, "Failed to query link config: %d\n", err);
+		goto out;
+	}
+
+	err = mana_verify_resp_hdr(&resp.hdr, MANA_QUERY_LINK_CONFIG,
+				   sizeof(resp));
+
+	if (err || resp.hdr.status) {
+		netdev_err(ndev, "Failed to query link config: %d, 0x%x\n", err,
+			   resp.hdr.status);
+		if (!err)
+			err = -EOPNOTSUPP;
+		goto out;
+	}
+
+	if (resp.qos_unconfigured) {
+		err = -EINVAL;
+		goto out;
+	}
+	apc->speed = resp.link_speed_mbps;
+	return 0;
+
+out:
+	return err;
+}
+
 int mana_create_wq_obj(struct mana_port_context *apc,
 		       mana_handle_t vport,
 		       u32 wq_type, struct mana_obj_spec *wq_spec,
diff --git a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c
index c419626073f5..48234a738d26 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c
@@ -427,6 +427,12 @@ static int mana_set_ringparam(struct net_device *ndev,
 static int mana_get_link_ksettings(struct net_device *ndev,
 				   struct ethtool_link_ksettings *cmd)
 {
+	struct mana_port_context *apc = netdev_priv(ndev);
+	int err;
+
+	err = mana_query_link_cfg(apc);
+
+	cmd->base.speed = (err) ? SPEED_UNKNOWN : apc->speed;
 	cmd->base.duplex = DUPLEX_FULL;
 	cmd->base.port = PORT_OTHER;
 
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 0f78065de8fe..63193613c185 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h
@@ -468,6 +468,8 @@ struct mana_port_context {
 
 	u16 port_idx;
 
+	u32 speed;
+
 	bool port_is_up;
 	bool port_st_save; /* Saved port state */
 
@@ -497,6 +499,7 @@ struct bpf_prog *mana_xdp_get(struct mana_port_context *apc);
 void mana_chn_setxdp(struct mana_port_context *apc, struct bpf_prog *prog);
 int mana_bpf(struct net_device *ndev, struct netdev_bpf *bpf);
 void mana_query_gf_stats(struct mana_port_context *apc);
+int mana_query_link_cfg(struct mana_port_context *apc);
 int mana_pre_alloc_rxbufs(struct mana_port_context *apc, int mtu, int num_queues);
 void mana_pre_dealloc_rxbufs(struct mana_port_context *apc);
 
@@ -523,6 +526,7 @@ enum mana_command_code {
 	MANA_FENCE_RQ		= 0x20006,
 	MANA_CONFIG_VPORT_RX	= 0x20007,
 	MANA_QUERY_VPORT_CONFIG	= 0x20008,
+	MANA_QUERY_LINK_CONFIG	= 0x2000A,
 
 	/* Privileged commands for the PF mode */
 	MANA_REGISTER_FILTER	= 0x28000,
@@ -531,6 +535,19 @@ enum mana_command_code {
 	MANA_DEREGISTER_HW_PORT	= 0x28004,
 };
 
+/* Query Link Configuration*/
+struct mana_query_link_config_req {
+	struct gdma_req_hdr hdr;
+	mana_handle_t vport;
+}; /* HW DATA */
+
+struct mana_query_link_config_resp {
+	struct gdma_resp_hdr hdr;
+	u32 link_speed_mbps;
+	u8 qos_unconfigured;
+	u8 reserved[3];
+}; /* HW DATA */
+
 /* Query Device Configuration */
 struct mana_query_device_cfg_req {
 	struct gdma_req_hdr hdr;
-- 
2.34.1

On Sun, Apr 20, 2025 at 11:33:38PM -0700, Erni Sri Satya Vennela wrote:
> Add support for speed in mana ethtool get_link_ksettings
> operation. This feature is not supported by all hardware.

This needs a lot more justification. tc(1) will show you the current
HTB Qdisc setting. No other MAC driver i know of will show you Qdisc
info in ksettings. So why is mana special?

Something your said in an earlier thread might be relevant here. There
are two shaper settings involved. The Hypervisor can configure a
limit, which the VM has no control over. And then you have this second
limit the VM can set, which only has any effect if it is lower than
the hypervisor limit.

The hypervisor limit is much more like the value ksettings represents,
the media speed, which is impossible to go above, and the machine has
no control over. Reporting that limit in ksettings would seem
reasonable. But it does not appear your firmware offers that?

    Andrew

---
pw-bot: cr

On Mon, Apr 21, 2025 at 02:36:43PM +0200, Andrew Lunn wrote:
> On Sun, Apr 20, 2025 at 11:33:38PM -0700, Erni Sri Satya Vennela wrote:
> > Add support for speed in mana ethtool get_link_ksettings
> > operation. This feature is not supported by all hardware.
> 
> This needs a lot more justification. tc(1) will show you the current
> HTB Qdisc setting. No other MAC driver i know of will show you Qdisc
> info in ksettings. So why is mana special?
> 
> Something your said in an earlier thread might be relevant here. There
> are two shaper settings involved. The Hypervisor can configure a
> limit, which the VM has no control over. And then you have this second
> limit the VM can set, which only has any effect if it is lower than
> the hypervisor limit.
> 
> The hypervisor limit is much more like the value ksettings represents,
> the media speed, which is impossible to go above, and the machine has
> no control over. Reporting that limit in ksettings would seem
> reasonable. But it does not appear your firmware offers that?
> 
>     Andrew
> 
Yes, that is correct. I will keep the ethtool mana_get_link_ksettings
unchanged, since the link speed can be reported using tc too. I will
make this change in the next version of the patch.
Thankyou for the pointer, Andrew.
> ---
> pw-bot: cr