RE: [net-next, v3, 05/10] ethtool: add a new command for getting PHC virtual clocks

Hi Jakub,

-----Original Message-----
From: Jakub Kicinski <kuba@kernel.org>
Sent: 2021年6月16日 3:49
To: Y.b. Lu <yangbo.lu@nxp.com>
Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org;
linux-kselftest@vger.kernel.org; mptcp@lists.linux.dev; Richard Cochran
[off-list ref]; David S . Miller [off-list ref]; Mat
Martineau [off-list ref]; Matthieu Baerts
[off-list ref]; Shuah Khan [off-list ref]; Michal
Kubecek [off-list ref]; Florian Fainelli [off-list ref];
Andrew Lunn [off-list ref]; Rui Sousa [off-list ref]; Sebastien
Laveze [off-list ref]
Subject: Re: [net-next, v3, 05/10] ethtool: add a new command for getting PHC
virtual clocks

On Tue, 15 Jun 2021 17:45:12 +0800 Yangbo Lu wrote:

quoted

Add an interface for getting PHC (PTP Hardware Clock) virtual clocks,
which are based on PHC physical clock providing hardware timestamp to
network packets.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>

quoted

diff --git a/include/uapi/linux/ethtool.h

b/include/uapi/linux/ethtool.h index cfef6b08169a..0fb04f945767 100644

--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h

@@ -17,6 +17,7 @@
 #include <linux/const.h>
 #include <linux/types.h>
 #include <linux/if_ether.h>
+#include <linux/ptp_clock.h>

 #ifndef __KERNEL__
 #include <limits.h> /* for INT_MAX */ @@ -1341,6 +1342,18 @@ struct

ethtool_ts_info {
 	__u32	rx_reserved[3];
 };

+/**
+ * struct ethtool_phc_vclocks - holds a device's PTP virtual clocks
+ * @cmd: command number = %ETHTOOL_GET_PHC_VCLOCKS
+ * @num: number of PTP vclocks
+ * @index: all index values of PTP vclocks  */ struct
+ethtool_phc_vclocks {
+	__u32	cmd;
+	__u8	num;
+	__s32	index[PTP_MAX_VCLOCKS];
+};
+
 /*
  * %ETHTOOL_SFEATURES changes features present in features[].valid to

the

quoted

  * values of corresponding bits in features[].requested. Bits in
.requested @@ -1552,6 +1565,7 @@ enum ethtool_fec_config_bits {
 #define ETHTOOL_PHY_STUNABLE	0x0000004f /* Set PHY tunable

configuration */

quoted

 #define ETHTOOL_GFECPARAM	0x00000050 /* Get FEC settings */
 #define ETHTOOL_SFECPARAM	0x00000051 /* Set FEC settings */
+#define ETHTOOL_GET_PHC_VCLOCKS	0x00000052 /* Get PHC virtual

clocks info */

We don't add new IOCTL commands, only netlink API is going to be extended.
Please remove the IOCTL interface & uAPI.

Will remove. Thanks.

quoted

 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET

quoted

+/* PHC VCLOCKS */
+
+enum {
+	ETHTOOL_A_PHC_VCLOCKS_UNSPEC,
+	ETHTOOL_A_PHC_VCLOCKS_HEADER,			/* nest - _A_HEADER_*

*/

quoted

+	ETHTOOL_A_PHC_VCLOCKS_NUM,			/* u8 */

u32, no need to limit yourself, the netlink attribute is rounded up to 4B
anyway.

Get it. Will use u32.

quoted

+	ETHTOOL_A_PHC_VCLOCKS_INDEX,			/* s32 */

This is an array, AFAICT, not a single s32.

Will fix. Thanks.

quoted

+
+	/* add new constants above here */
+	__ETHTOOL_A_PHC_VCLOCKS_CNT,
+	ETHTOOL_A_PHC_VCLOCKS_MAX = (__ETHTOOL_A_PHC_VCLOCKS_CNT -

1) };

quoted

+
 /* CABLE TEST */

 enum {

quoted

+static int phc_vclocks_fill_reply(struct sk_buff *skb,
+				  const struct ethnl_req_info *req_base,
+				  const struct ethnl_reply_data *reply_base) {
+	const struct phc_vclocks_reply_data *data =
+		PHC_VCLOCKS_REPDATA(reply_base);
+	const struct ethtool_phc_vclocks *phc_vclocks = &data->phc_vclocks;
+
+	if (phc_vclocks->num <= 0)
+		return 0;
+
+	if (nla_put_u32(skb, ETHTOOL_A_PHC_VCLOCKS_NUM, phc_vclocks->num)

||

quoted

+	    nla_put(skb, ETHTOOL_A_PHC_VCLOCKS_INDEX,
+		    sizeof(phc_vclocks->index), phc_vclocks->index))

Looks like you'll report the whole array, why not just num?

Will report just num. Thanks.

quoted

+		return -EMSGSIZE;
+
+	return 0;
+}
+
+const struct ethnl_request_ops ethnl_phc_vclocks_request_ops = {
+	.request_cmd		= ETHTOOL_MSG_PHC_VCLOCKS_GET,
+	.reply_cmd		= ETHTOOL_MSG_PHC_VCLOCKS_GET_REPLY,
+	.hdr_attr		= ETHTOOL_A_PHC_VCLOCKS_HEADER,
+	.req_info_size		= sizeof(struct phc_vclocks_req_info),
+	.reply_data_size	= sizeof(struct phc_vclocks_reply_data),
+
+	.prepare_data		= phc_vclocks_prepare_data,
+	.reply_size		= phc_vclocks_reply_size,
+	.fill_reply		= phc_vclocks_fill_reply,
+};