2022-12-05 17:37:57

by Piergiorgio Beruto

[permalink] [raw]
Subject: [PATCH v3 net-next 1/4] net/ethtool: add netlink interface for the PLCA RS

Add support for configuring the PLCA Reconciliation Sublayer on
multi-drop PHYs that support IEEE802.3cg-2019 Clause 148 (e.g.,
10BASE-T1S). This patch adds the appropriate netlink interface
to ethtool.

Signed-off-by: Piergiorgio Beruto <[email protected]>
---
MAINTAINERS | 6 +
drivers/net/phy/phy.c | 34 ++++
drivers/net/phy/phy_device.c | 3 +
include/linux/ethtool.h | 11 +
include/linux/phy.h | 64 ++++++
include/uapi/linux/ethtool_netlink.h | 25 +++
net/ethtool/Makefile | 2 +-
net/ethtool/netlink.c | 30 +++
net/ethtool/netlink.h | 6 +
net/ethtool/plca.c | 290 +++++++++++++++++++++++++++
10 files changed, 470 insertions(+), 1 deletion(-)
create mode 100644 net/ethtool/plca.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 955c1be1efb2..7952243e4b43 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16396,6 +16396,12 @@ S: Maintained
F: Documentation/devicetree/bindings/iio/chemical/plantower,pms7003.yaml
F: drivers/iio/chemical/pms7003.c

+PLCA RECONCILIATION SUBLAYER (IEEE802.3 Clause 148)
+M: Piergiorgio Beruto <[email protected]>
+L: [email protected]
+S: Maintained
+F: net/ethtool/plca.c
+
PLDMFW LIBRARY
M: Jacob Keller <[email protected]>
S: Maintained
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index e5b6cb1a77f9..99e3497b6aa1 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -543,6 +543,40 @@ int phy_ethtool_get_stats(struct phy_device *phydev,
}
EXPORT_SYMBOL(phy_ethtool_get_stats);

+/**
+ *
+ */
+int phy_ethtool_get_plca_cfg(struct phy_device *dev,
+ struct phy_plca_cfg *plca_cfg)
+{
+ // TODO
+ return 0;
+}
+EXPORT_SYMBOL(phy_ethtool_get_plca_cfg);
+
+/**
+ *
+ */
+int phy_ethtool_set_plca_cfg(struct phy_device *dev,
+ struct netlink_ext_ack *extack,
+ const struct phy_plca_cfg *plca_cfg)
+{
+ // TODO
+ return 0;
+}
+EXPORT_SYMBOL(phy_ethtool_set_plca_cfg);
+
+/**
+ *
+ */
+int phy_ethtool_get_plca_status(struct phy_device *dev,
+ struct phy_plca_status *plca_st)
+{
+ // TODO
+ return 0;
+}
+EXPORT_SYMBOL(phy_ethtool_get_plca_status);
+
/**
* phy_start_cable_test - Start a cable test
*
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 716870a4499c..f248010c403d 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -3262,6 +3262,9 @@ static const struct ethtool_phy_ops phy_ethtool_phy_ops = {
.get_sset_count = phy_ethtool_get_sset_count,
.get_strings = phy_ethtool_get_strings,
.get_stats = phy_ethtool_get_stats,
+ .get_plca_cfg = phy_ethtool_get_plca_cfg,
+ .set_plca_cfg = phy_ethtool_set_plca_cfg,
+ .get_plca_status = phy_ethtool_get_plca_status,
.start_cable_test = phy_start_cable_test,
.start_cable_test_tdr = phy_start_cable_test_tdr,
};
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 9e0a76fc7de9..4bfe95ec1f0a 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -802,12 +802,16 @@ int ethtool_virtdev_set_link_ksettings(struct net_device *dev,

struct phy_device;
struct phy_tdr_config;
+struct phy_plca_cfg;
+struct phy_plca_status;

/**
* struct ethtool_phy_ops - Optional PHY device options
* @get_sset_count: Get number of strings that @get_strings will write.
* @get_strings: Return a set of strings that describe the requested objects
* @get_stats: Return extended statistics about the PHY device.
+ * @get_plca_cfg: Return PLCA configuration.
+ * @set_plca_cfg: Set PLCA configuration.
* @start_cable_test: Start a cable test
* @start_cable_test_tdr: Start a Time Domain Reflectometry cable test
*
@@ -819,6 +823,13 @@ struct ethtool_phy_ops {
int (*get_strings)(struct phy_device *dev, u8 *data);
int (*get_stats)(struct phy_device *dev,
struct ethtool_stats *stats, u64 *data);
+ int (*get_plca_cfg)(struct phy_device *dev,
+ struct phy_plca_cfg *plca_cfg);
+ int (*set_plca_cfg)(struct phy_device *dev,
+ struct netlink_ext_ack *extack,
+ const struct phy_plca_cfg *plca_cfg);
+ int (*get_plca_status)(struct phy_device *dev,
+ struct phy_plca_status *plca_st);
int (*start_cable_test)(struct phy_device *phydev,
struct netlink_ext_ack *extack);
int (*start_cable_test_tdr)(struct phy_device *phydev,
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 71eeb4e3b1fd..ab2c134d0a05 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -765,6 +765,63 @@ struct phy_tdr_config {
};
#define PHY_PAIR_ALL -1

+/**
+ * struct phy_plca_cfg - Configuration of the PLCA (Physical Layer Collision
+ * Avoidance) Reconciliation Sublayer.
+ *
+ * @version: read-only PLCA register map version. 0 = not available. Ignored
+ * when setting the configuration. Format is the same as reported by the PLCA
+ * IDVER register (31.CA00). -1 = not available.
+ * @enabled: PLCA configured mode (enabled/disabled). -1 = not available / don't
+ * set. 0 = disabled, anything else = enabled.
+ * @node_id: the PLCA local node identifier. -1 = not available / don't set.
+ * Allowed values [0 .. 254]. 255 = node disabled.
+ * @node_cnt: the PLCA node count (maximum number of nodes having a TO). Only
+ * meaningful for the coordinator (node_id = 0). -1 = not available / don't
+ * set. Allowed values [0 .. 255].
+ * @to_tmr: The value of the PLCA to_timer in bit-times, which determines the
+ * PLCA transmit opportunity window opening. See IEEE802.3 Clause 148 for
+ * more details. The to_timer shall be set equal over all nodes.
+ * -1 = not available / don't set. Allowed values [0 .. 255].
+ * @burst_cnt: controls how many additional frames a node is allowed to send in
+ * single transmit opportunity (TO). The default value of 0 means that the
+ * node is allowed exactly one frame per TO. A value of 1 allows two frames
+ * per TO, and so on. -1 = not available / don't set.
+ * Allowed values [0 .. 255].
+ * @burst_tmr: controls how many bit times to wait for the MAC to send a new
+ * frame before interrupting the burst. This value should be set to a value
+ * greater than the MAC inter-packet gap (which is typically 96 bits).
+ * -1 = not available / don't set. Allowed values [0 .. 255].
+ *
+ * A structure containing configuration parameters for setting/getting the PLCA
+ * RS configuration. The driver does not need to implement all the parameters,
+ * but should report what is actually used.
+ */
+struct phy_plca_cfg {
+ s32 version;
+ s16 enabled;
+ s16 node_id;
+ s16 node_cnt;
+ s16 to_tmr;
+ s16 burst_cnt;
+ s16 burst_tmr;
+};
+
+/**
+ * struct phy_plca_status - Status of the PLCA (Physical Layer Collision
+ * Avoidance) Reconciliation Sublayer.
+ *
+ * @pst: The PLCA status as reported by the PST bit in the PLCA STATUS
+ * register(31.CA03), indicating BEACON activity.
+ *
+ * A structure containing status information of the PLCA RS configuration.
+ * The driver does not need to implement all the parameters, but should report
+ * what is actually used.
+ */
+struct phy_plca_status {
+ bool pst;
+};
+
/**
* struct phy_driver - Driver structure for a particular PHY type
*
@@ -1775,6 +1832,13 @@ int phy_ethtool_get_strings(struct phy_device *phydev, u8 *data);
int phy_ethtool_get_sset_count(struct phy_device *phydev);
int phy_ethtool_get_stats(struct phy_device *phydev,
struct ethtool_stats *stats, u64 *data);
+int phy_ethtool_get_plca_cfg(struct phy_device *dev,
+ struct phy_plca_cfg *plca_cfg);
+int phy_ethtool_set_plca_cfg(struct phy_device *dev,
+ struct netlink_ext_ack *extack,
+ const struct phy_plca_cfg *plca_cfg);
+int phy_ethtool_get_plca_status(struct phy_device *dev,
+ struct phy_plca_status *plca_st);

static inline int phy_package_read(struct phy_device *phydev, u32 regnum)
{
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index aaf7c6963d61..81e3d7b42d0f 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -51,6 +51,9 @@ enum {
ETHTOOL_MSG_MODULE_SET,
ETHTOOL_MSG_PSE_GET,
ETHTOOL_MSG_PSE_SET,
+ ETHTOOL_MSG_PLCA_GET_CFG,
+ ETHTOOL_MSG_PLCA_SET_CFG,
+ ETHTOOL_MSG_PLCA_GET_STATUS,

/* add new constants above here */
__ETHTOOL_MSG_USER_CNT,
@@ -97,6 +100,9 @@ enum {
ETHTOOL_MSG_MODULE_GET_REPLY,
ETHTOOL_MSG_MODULE_NTF,
ETHTOOL_MSG_PSE_GET_REPLY,
+ ETHTOOL_MSG_PLCA_GET_CFG_REPLY,
+ ETHTOOL_MSG_PLCA_GET_STATUS_REPLY,
+ ETHTOOL_MSG_PLCA_NTF,

/* add new constants above here */
__ETHTOOL_MSG_KERNEL_CNT,
@@ -880,6 +886,25 @@ enum {
ETHTOOL_A_PSE_MAX = (__ETHTOOL_A_PSE_CNT - 1)
};

+/* PLCA */
+
+enum {
+ ETHTOOL_A_PLCA_UNSPEC,
+ ETHTOOL_A_PLCA_HEADER, /* nest - _A_HEADER_* */
+ ETHTOOL_A_PLCA_VERSION, /* u16 */
+ ETHTOOL_A_PLCA_ENABLED, /* u8 */
+ ETHTOOL_A_PLCA_STATUS, /* u8 */
+ ETHTOOL_A_PLCA_NODE_CNT, /* u8 */
+ ETHTOOL_A_PLCA_NODE_ID, /* u8 */
+ ETHTOOL_A_PLCA_TO_TMR, /* u8 */
+ ETHTOOL_A_PLCA_BURST_CNT, /* u8 */
+ ETHTOOL_A_PLCA_BURST_TMR, /* u8 */
+
+ /* add new constants above here */
+ __ETHTOOL_A_PLCA_CNT,
+ ETHTOOL_A_PLCA_MAX = (__ETHTOOL_A_PLCA_CNT - 1)
+};
+
/* generic netlink info */
#define ETHTOOL_GENL_NAME "ethtool"
#define ETHTOOL_GENL_VERSION 1
diff --git a/net/ethtool/Makefile b/net/ethtool/Makefile
index 72ab0944262a..b18930e2ce9a 100644
--- a/net/ethtool/Makefile
+++ b/net/ethtool/Makefile
@@ -8,4 +8,4 @@ ethtool_nl-y := netlink.o bitset.o strset.o linkinfo.o linkmodes.o \
linkstate.o debug.o wol.o features.o privflags.o rings.o \
channels.o coalesce.o pause.o eee.o tsinfo.o cabletest.o \
tunnels.o fec.o eeprom.o stats.o phc_vclocks.o module.o \
- pse-pd.o
+ pse-pd.o plca.o
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 1a4c11356c96..eb044f48cb24 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -287,6 +287,8 @@ ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
[ETHTOOL_MSG_PHC_VCLOCKS_GET] = &ethnl_phc_vclocks_request_ops,
[ETHTOOL_MSG_MODULE_GET] = &ethnl_module_request_ops,
[ETHTOOL_MSG_PSE_GET] = &ethnl_pse_request_ops,
+ [ETHTOOL_MSG_PLCA_GET_CFG] = &ethnl_plca_cfg_request_ops,
+ [ETHTOOL_MSG_PLCA_GET_STATUS] = &ethnl_plca_status_request_ops,
};

static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
@@ -602,6 +604,7 @@ ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
[ETHTOOL_MSG_EEE_NTF] = &ethnl_eee_request_ops,
[ETHTOOL_MSG_FEC_NTF] = &ethnl_fec_request_ops,
[ETHTOOL_MSG_MODULE_NTF] = &ethnl_module_request_ops,
+ [ETHTOOL_MSG_PLCA_NTF] = &ethnl_plca_cfg_request_ops,
};

/* default notification handler */
@@ -695,6 +698,7 @@ static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
[ETHTOOL_MSG_EEE_NTF] = ethnl_default_notify,
[ETHTOOL_MSG_FEC_NTF] = ethnl_default_notify,
[ETHTOOL_MSG_MODULE_NTF] = ethnl_default_notify,
+ [ETHTOOL_MSG_PLCA_NTF] = ethnl_default_notify,
};

void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
@@ -1040,6 +1044,32 @@ static const struct genl_ops ethtool_genl_ops[] = {
.policy = ethnl_pse_set_policy,
.maxattr = ARRAY_SIZE(ethnl_pse_set_policy) - 1,
},
+ {
+ .cmd = ETHTOOL_MSG_PLCA_GET_CFG,
+ .doit = ethnl_default_doit,
+ .start = ethnl_default_start,
+ .dumpit = ethnl_default_dumpit,
+ .done = ethnl_default_done,
+ .policy = ethnl_plca_get_cfg_policy,
+ .maxattr = ARRAY_SIZE(ethnl_plca_get_cfg_policy) - 1,
+ },
+ {
+ .cmd = ETHTOOL_MSG_PLCA_SET_CFG,
+ .flags = GENL_UNS_ADMIN_PERM,
+ .doit = ethnl_set_plca_cfg,
+ .policy = ethnl_plca_set_cfg_policy,
+ .maxattr = ARRAY_SIZE(ethnl_plca_set_cfg_policy) - 1,
+ },
+ {
+ .cmd = ETHTOOL_MSG_PLCA_GET_STATUS,
+ .doit = ethnl_default_doit,
+ .start = ethnl_default_start,
+ .dumpit = ethnl_default_dumpit,
+ .done = ethnl_default_done,
+ .policy = ethnl_plca_get_status_policy,
+ .maxattr = ARRAY_SIZE(ethnl_plca_get_status_policy) - 1,
+ },
+
};

static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 1bfd374f9718..c0ed1a6d0833 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -346,6 +346,8 @@ extern const struct ethnl_request_ops ethnl_stats_request_ops;
extern const struct ethnl_request_ops ethnl_phc_vclocks_request_ops;
extern const struct ethnl_request_ops ethnl_module_request_ops;
extern const struct ethnl_request_ops ethnl_pse_request_ops;
+extern const struct ethnl_request_ops ethnl_plca_cfg_request_ops;
+extern const struct ethnl_request_ops ethnl_plca_status_request_ops;

extern const struct nla_policy ethnl_header_policy[ETHTOOL_A_HEADER_FLAGS + 1];
extern const struct nla_policy ethnl_header_policy_stats[ETHTOOL_A_HEADER_FLAGS + 1];
@@ -386,6 +388,9 @@ extern const struct nla_policy ethnl_module_get_policy[ETHTOOL_A_MODULE_HEADER +
extern const struct nla_policy ethnl_module_set_policy[ETHTOOL_A_MODULE_POWER_MODE_POLICY + 1];
extern const struct nla_policy ethnl_pse_get_policy[ETHTOOL_A_PSE_HEADER + 1];
extern const struct nla_policy ethnl_pse_set_policy[ETHTOOL_A_PSE_MAX + 1];
+extern const struct nla_policy ethnl_plca_get_cfg_policy[ETHTOOL_A_PLCA_HEADER + 1];
+extern const struct nla_policy ethnl_plca_set_cfg_policy[ETHTOOL_A_PLCA_MAX + 1];
+extern const struct nla_policy ethnl_plca_get_status_policy[ETHTOOL_A_PLCA_HEADER + 1];

int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);
@@ -406,6 +411,7 @@ int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
int ethnl_set_fec(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_module(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_pse(struct sk_buff *skb, struct genl_info *info);
+int ethnl_set_plca_cfg(struct sk_buff *skb, struct genl_info *info);

extern const char stats_std_names[__ETHTOOL_STATS_CNT][ETH_GSTRING_LEN];
extern const char stats_eth_phy_names[__ETHTOOL_A_STATS_ETH_PHY_CNT][ETH_GSTRING_LEN];
diff --git a/net/ethtool/plca.c b/net/ethtool/plca.c
new file mode 100644
index 000000000000..0282acab1c4d
--- /dev/null
+++ b/net/ethtool/plca.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/phy.h>
+#include <linux/ethtool_netlink.h>
+
+#include "netlink.h"
+#include "common.h"
+
+struct plca_req_info {
+ struct ethnl_req_info base;
+};
+
+struct plca_reply_data {
+ struct ethnl_reply_data base;
+ struct phy_plca_cfg plca_cfg;
+ struct phy_plca_status plca_st;
+};
+
+#define PLCA_REPDATA(__reply_base) \
+ container_of(__reply_base, struct plca_reply_data, base)
+
+// PLCA get configuration message ------------------------------------------- //
+
+const struct nla_policy ethnl_plca_get_cfg_policy[] = {
+ [ETHTOOL_A_PLCA_HEADER] =
+ NLA_POLICY_NESTED(ethnl_header_policy),
+};
+
+static int plca_get_cfg_prepare_data(const struct ethnl_req_info *req_base,
+ struct ethnl_reply_data *reply_base,
+ struct genl_info *info)
+{
+ struct plca_reply_data *data = PLCA_REPDATA(reply_base);
+ struct net_device *dev = reply_base->dev;
+ const struct ethtool_phy_ops *ops;
+ int ret;
+
+ // check that the PHY device is available and connected
+ if (!dev->phydev) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ // note: rtnl_lock is held already by ethnl_default_doit
+ ops = ethtool_phy_ops;
+ if (!ops || !ops->get_plca_cfg) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ ret = ethnl_ops_begin(dev);
+ if (ret < 0)
+ goto out;
+
+ ret = ops->get_plca_cfg(dev->phydev, &data->plca_cfg);
+ if (ret < 0)
+ goto out;
+
+ ethnl_ops_complete(dev);
+
+out:
+ return ret;
+}
+
+static int plca_get_cfg_reply_size(const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ return nla_total_size(sizeof(u16)) + /* _VERSION */
+ nla_total_size(sizeof(u8)) + /* _ENABLED */
+ nla_total_size(sizeof(u8)) + /* _STATUS */
+ nla_total_size(sizeof(u8)) + /* _NODE_CNT */
+ nla_total_size(sizeof(u8)) + /* _NODE_ID */
+ nla_total_size(sizeof(u8)) + /* _TO_TIMER */
+ nla_total_size(sizeof(u8)) + /* _BURST_COUNT */
+ nla_total_size(sizeof(u8)); /* _BURST_TIMER */
+}
+
+static int plca_get_cfg_fill_reply(struct sk_buff *skb,
+ const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct plca_reply_data *data = PLCA_REPDATA(reply_base);
+ const struct phy_plca_cfg *plca = &data->plca_cfg;
+
+ if ((plca->version >= 0 &&
+ nla_put_u16(skb, ETHTOOL_A_PLCA_VERSION, (u16)plca->version)) ||
+ (plca->enabled >= 0 &&
+ nla_put_u8(skb, ETHTOOL_A_PLCA_ENABLED, !!plca->enabled)) ||
+ (plca->node_id >= 0 &&
+ nla_put_u8(skb, ETHTOOL_A_PLCA_NODE_ID, (u8)plca->node_id)) ||
+ (plca->node_cnt >= 0 &&
+ nla_put_u8(skb, ETHTOOL_A_PLCA_NODE_CNT, (u8)plca->node_cnt)) ||
+ (plca->to_tmr >= 0 &&
+ nla_put_u8(skb, ETHTOOL_A_PLCA_TO_TMR, (u8)plca->to_tmr)) ||
+ (plca->burst_cnt >= 0 &&
+ nla_put_u8(skb, ETHTOOL_A_PLCA_BURST_CNT, (u8)plca->burst_cnt)) ||
+ (plca->burst_tmr >= 0 &&
+ nla_put_u8(skb, ETHTOOL_A_PLCA_BURST_TMR, (u8)plca->burst_tmr)))
+ return -EMSGSIZE;
+
+ return 0;
+};
+
+const struct ethnl_request_ops ethnl_plca_cfg_request_ops = {
+ .request_cmd = ETHTOOL_MSG_PLCA_GET_CFG,
+ .reply_cmd = ETHTOOL_MSG_PLCA_GET_CFG_REPLY,
+ .hdr_attr = ETHTOOL_A_PLCA_HEADER,
+ .req_info_size = sizeof(struct plca_req_info),
+ .reply_data_size = sizeof(struct plca_reply_data),
+
+ .prepare_data = plca_get_cfg_prepare_data,
+ .reply_size = plca_get_cfg_reply_size,
+ .fill_reply = plca_get_cfg_fill_reply,
+};
+
+// PLCA set configuration message ------------------------------------------- //
+
+const struct nla_policy ethnl_plca_set_cfg_policy[] = {
+ [ETHTOOL_A_PLCA_HEADER] =
+ NLA_POLICY_NESTED(ethnl_header_policy),
+ [ETHTOOL_A_PLCA_ENABLED] = { .type = NLA_U8 },
+ [ETHTOOL_A_PLCA_NODE_ID] = { .type = NLA_U8 },
+ [ETHTOOL_A_PLCA_NODE_CNT] = { .type = NLA_U8 },
+ [ETHTOOL_A_PLCA_TO_TMR] = { .type = NLA_U8 },
+ [ETHTOOL_A_PLCA_BURST_CNT] = { .type = NLA_U8 },
+ [ETHTOOL_A_PLCA_BURST_TMR] = { .type = NLA_U8 },
+};
+
+int ethnl_set_plca_cfg(struct sk_buff *skb, struct genl_info *info)
+{
+ struct ethnl_req_info req_info = {};
+ struct nlattr **tb = info->attrs;
+ const struct ethtool_phy_ops *ops;
+ struct phy_plca_cfg plca_cfg;
+ struct net_device *dev;
+
+ bool mod = false;
+ int ret;
+
+ ret = ethnl_parse_header_dev_get(&req_info,
+ tb[ETHTOOL_A_PLCA_HEADER],
+ genl_info_net(info), info->extack,
+ true);
+ if (ret < 0)
+ return ret;
+
+ dev = req_info.dev;
+
+ // check that the PHY device is available and connected
+ rtnl_lock();
+
+ if (!dev->phydev) {
+ ret = -EOPNOTSUPP;
+ goto out_rtnl;
+ }
+
+ ops = ethtool_phy_ops;
+ if (!ops || !ops->set_plca_cfg) {
+ ret = -EOPNOTSUPP;
+ goto out_rtnl;
+ }
+
+ ret = ethnl_ops_begin(dev);
+ if (ret < 0)
+ goto out_rtnl;
+
+ memset(&plca_cfg, 0xFF, sizeof(plca_cfg));
+
+ if (tb[ETHTOOL_A_PLCA_ENABLED]) {
+ plca_cfg.enabled = !!nla_get_u8(tb[ETHTOOL_A_PLCA_ENABLED]);
+ mod = true;
+ }
+
+ if (tb[ETHTOOL_A_PLCA_NODE_ID]) {
+ plca_cfg.node_id = nla_get_u8(tb[ETHTOOL_A_PLCA_NODE_ID]);
+ mod = true;
+ }
+
+ if (tb[ETHTOOL_A_PLCA_NODE_CNT]) {
+ plca_cfg.node_cnt = nla_get_u8(tb[ETHTOOL_A_PLCA_NODE_CNT]);
+ mod = true;
+ }
+
+ if (tb[ETHTOOL_A_PLCA_TO_TMR]) {
+ plca_cfg.to_tmr = nla_get_u8(tb[ETHTOOL_A_PLCA_TO_TMR]);
+ mod = true;
+ }
+
+ if (tb[ETHTOOL_A_PLCA_BURST_CNT]) {
+ plca_cfg.burst_cnt = nla_get_u8(tb[ETHTOOL_A_PLCA_BURST_CNT]);
+ mod = true;
+ }
+
+ if (tb[ETHTOOL_A_PLCA_BURST_TMR]) {
+ plca_cfg.burst_tmr = nla_get_u8(tb[ETHTOOL_A_PLCA_BURST_TMR]);
+ mod = true;
+ }
+
+ ret = 0;
+ if (!mod)
+ goto out_ops;
+
+ ret = ops->set_plca_cfg(dev->phydev, info->extack, &plca_cfg);
+
+ if (ret < 0)
+ goto out_ops;
+
+ ethtool_notify(dev, ETHTOOL_MSG_PLCA_NTF, NULL);
+
+out_ops:
+ ethnl_ops_complete(dev);
+out_rtnl:
+ rtnl_unlock();
+ ethnl_parse_header_dev_put(&req_info);
+
+ return ret;
+}
+
+// PLCA get status message -------------------------------------------------- //
+
+const struct nla_policy ethnl_plca_get_status_policy[] = {
+ [ETHTOOL_A_PLCA_HEADER] =
+ NLA_POLICY_NESTED(ethnl_header_policy),
+};
+
+static int plca_get_status_prepare_data(const struct ethnl_req_info *req_base,
+ struct ethnl_reply_data *reply_base,
+ struct genl_info *info)
+{
+ struct plca_reply_data *data = PLCA_REPDATA(reply_base);
+ struct net_device *dev = reply_base->dev;
+ const struct ethtool_phy_ops *ops;
+ int ret;
+
+ // check that the PHY device is available and connected
+ if (!dev->phydev) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ // note: rtnl_lock is held already by ethnl_default_doit
+ ops = ethtool_phy_ops;
+ if (!ops || !ops->get_plca_status) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ ret = ethnl_ops_begin(dev);
+ if (ret < 0)
+ goto out;
+
+ ret = ops->get_plca_status(dev->phydev, &data->plca_st);
+ if (ret < 0)
+ goto out;
+
+ ethnl_ops_complete(dev);
+out:
+ return ret;
+}
+
+static int plca_get_status_reply_size(const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ return nla_total_size(sizeof(u8)); /* _STATUS */
+}
+
+static int plca_get_status_fill_reply(struct sk_buff *skb,
+ const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct plca_reply_data *data = PLCA_REPDATA(reply_base);
+ const u8 status = data->plca_st.pst;
+
+ if (nla_put_u8(skb, ETHTOOL_A_PLCA_STATUS, !!status))
+ return -EMSGSIZE;
+
+ return 0;
+};
+
+const struct ethnl_request_ops ethnl_plca_status_request_ops = {
+ .request_cmd = ETHTOOL_MSG_PLCA_GET_STATUS,
+ .reply_cmd = ETHTOOL_MSG_PLCA_GET_STATUS_REPLY,
+ .hdr_attr = ETHTOOL_A_PLCA_HEADER,
+ .req_info_size = sizeof(struct plca_req_info),
+ .reply_data_size = sizeof(struct plca_reply_data),
+
+ .prepare_data = plca_get_status_prepare_data,
+ .reply_size = plca_get_status_reply_size,
+ .fill_reply = plca_get_status_fill_reply,
+};
--
2.35.1


2022-12-05 18:47:14

by Russell King (Oracle)

[permalink] [raw]
Subject: Re: [PATCH v3 net-next 1/4] net/ethtool: add netlink interface for the PLCA RS

On Mon, Dec 05, 2022 at 06:17:37PM +0100, Piergiorgio Beruto wrote:
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index e5b6cb1a77f9..99e3497b6aa1 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -543,6 +543,40 @@ int phy_ethtool_get_stats(struct phy_device *phydev,
> }
> EXPORT_SYMBOL(phy_ethtool_get_stats);
>
> +/**
> + *
> + */
> +int phy_ethtool_get_plca_cfg(struct phy_device *dev,
> + struct phy_plca_cfg *plca_cfg)
> +{
> + // TODO
> + return 0;
> +}
> +EXPORT_SYMBOL(phy_ethtool_get_plca_cfg);
> +
> +/**
> + *
> + */
> +int phy_ethtool_set_plca_cfg(struct phy_device *dev,
> + struct netlink_ext_ack *extack,
> + const struct phy_plca_cfg *plca_cfg)
> +{
> + // TODO
> + return 0;
> +}
> +EXPORT_SYMBOL(phy_ethtool_set_plca_cfg);
> +
> +/**
> + *
> + */
> +int phy_ethtool_get_plca_status(struct phy_device *dev,
> + struct phy_plca_status *plca_st)
> +{
> + // TODO
> + return 0;
> +}
> +EXPORT_SYMBOL(phy_ethtool_get_plca_status);
> +
> /**
> * phy_start_cable_test - Start a cable test
> *
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index 716870a4499c..f248010c403d 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -3262,6 +3262,9 @@ static const struct ethtool_phy_ops phy_ethtool_phy_ops = {
> .get_sset_count = phy_ethtool_get_sset_count,
> .get_strings = phy_ethtool_get_strings,
> .get_stats = phy_ethtool_get_stats,
> + .get_plca_cfg = phy_ethtool_get_plca_cfg,
> + .set_plca_cfg = phy_ethtool_set_plca_cfg,
> + .get_plca_status = phy_ethtool_get_plca_status,
> .start_cable_test = phy_start_cable_test,
> .start_cable_test_tdr = phy_start_cable_test_tdr,
> };

From what I can see, none of the above changes need to be part of
patch 1 - nothing in the rest of the patch requires these members to be
filled in, since you explicitly test to see whether they are before
calling them.

So, rather than introducing docbook stubs and stub functions that
do nothing, marked with "TODO" comments, just merge these changes
above with patch 3, where you actually populate these functions.

Also, why do they need to be exported to modules? From what I can see,
the only user of these functions is phy_device.c, which is part of
the same module as phy.c where the functions live, meaning that they
don't need to be exported.

It's also surely wrong to introduce stubs that return success but
do nothing.

--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

2022-12-05 18:58:52

by Piergiorgio Beruto

[permalink] [raw]
Subject: Re: [PATCH v3 net-next 1/4] net/ethtool: add netlink interface for the PLCA RS

On Mon, Dec 05, 2022 at 06:05:07PM +0000, Russell King (Oracle) wrote:
> On Mon, Dec 05, 2022 at 06:17:37PM +0100, Piergiorgio Beruto wrote:
> > diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> > index e5b6cb1a77f9..99e3497b6aa1 100644
> > --- a/drivers/net/phy/phy.c
> > +++ b/drivers/net/phy/phy.c
> > @@ -543,6 +543,40 @@ int phy_ethtool_get_stats(struct phy_device *phydev,
> > }
> > EXPORT_SYMBOL(phy_ethtool_get_stats);
> >
> > +/**
> > + *
> > + */
> > +int phy_ethtool_get_plca_cfg(struct phy_device *dev,
> > + struct phy_plca_cfg *plca_cfg)
> > +{
> > + // TODO
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(phy_ethtool_get_plca_cfg);
> > +
> > +/**
> > + *
> > + */
> > +int phy_ethtool_set_plca_cfg(struct phy_device *dev,
> > + struct netlink_ext_ack *extack,
> > + const struct phy_plca_cfg *plca_cfg)
> > +{
> > + // TODO
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(phy_ethtool_set_plca_cfg);
> > +
> > +/**
> > + *
> > + */
> > +int phy_ethtool_get_plca_status(struct phy_device *dev,
> > + struct phy_plca_status *plca_st)
> > +{
> > + // TODO
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(phy_ethtool_get_plca_status);
> > +
> > /**
> > * phy_start_cable_test - Start a cable test
> > *
> > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> > index 716870a4499c..f248010c403d 100644
> > --- a/drivers/net/phy/phy_device.c
> > +++ b/drivers/net/phy/phy_device.c
> > @@ -3262,6 +3262,9 @@ static const struct ethtool_phy_ops phy_ethtool_phy_ops = {
> > .get_sset_count = phy_ethtool_get_sset_count,
> > .get_strings = phy_ethtool_get_strings,
> > .get_stats = phy_ethtool_get_stats,
> > + .get_plca_cfg = phy_ethtool_get_plca_cfg,
> > + .set_plca_cfg = phy_ethtool_set_plca_cfg,
> > + .get_plca_status = phy_ethtool_get_plca_status,
> > .start_cable_test = phy_start_cable_test,
> > .start_cable_test_tdr = phy_start_cable_test_tdr,
> > };
>
> From what I can see, none of the above changes need to be part of
> patch 1 - nothing in the rest of the patch requires these members to be
> filled in, since you explicitly test to see whether they are before
> calling them.
My apologies, in my understanding of this process (which is new to me)
the idea of dividing the patches into smaller parts is to facilitate the
review. It was not clear to me that the single patches had to be
self-consistent also from a formal perspective. I was assuming that a
patchset can be accepted or rejected as a whole. Is this the case, or
can you accept only a subset of patches in a set?

In short, I did this because I -thought- it would help the reader
understanding what the intention of the change would be. If this is not
the case, fair enough, I'll not do this in the future.

>
> So, rather than introducing docbook stubs and stub functions that
> do nothing, marked with "TODO" comments, just merge these changes
> above with patch 3, where you actually populate these functions.
Clear. Do you want me to regenerate the patches into a v4 or do you
think we can move forward with v3 anyway?

> Also, why do they need to be exported to modules? From what I can see,
> the only user of these functions is phy_device.c, which is part of
> the same module as phy.c where the functions live, meaning that they
> don't need to be exported.
I did this because similar functions in the same file are all exported
to modules (e.g. phy_config_aneg, phy_speed_down, phy_start_cable_test).
Therefore, I assumed the intention was to let modules (maybe out-of-tree
modules?) make use of these functions. If you think we should not do
this, would kindly explain why for example the phy_start_cable_test is
exported? I'm really asking because I'm trying to learn the rationales
behind the architectural choices that I see here.

>
> It's also surely wrong to introduce stubs that return success but
> do nothing.
No doubt it would be wrong if the patch can be integrated regardless of
the other patches in the same set.

>
> --
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

2022-12-06 03:38:08

by Andrew Lunn

[permalink] [raw]
Subject: Re: [PATCH v3 net-next 1/4] net/ethtool: add netlink interface for the PLCA RS

> > Also, why do they need to be exported to modules? From what I can see,
> > the only user of these functions is phy_device.c, which is part of
> > the same module as phy.c where the functions live, meaning that they
> > don't need to be exported.
> I did this because similar functions in the same file are all exported
> to modules (e.g. phy_config_aneg, phy_speed_down, phy_start_cable_test).
> Therefore, I assumed the intention was to let modules (maybe out-of-tree
> modules?) make use of these functions. If you think we should not do
> this, would kindly explain why for example the phy_start_cable_test is
> exported?

phy_start_cable_test probably should not be exported. I probably got
this wrong. At one point, it might of been called directly from
net/ethtool/cabletest.c, but not any more. It is now accessed via
phy_ethtool_phy_ops.

Each kernel module is its own name space. You can only reference
something within a kernel module if it is exported. So you will find
all the helper functions in phy_device.c which are used by PHY drivers
are exported, for example.

You need to watch out for circular dependencies between modules, since
they are loaded sequentially. PHYs are generally leaves, they depend
on phylib and nothing else, so that is simple. The phylib module is
loaded first, and then the PHY drivers.

But there are more complex scenarios. A built in driver cannot
reference a module, that would result in undefined symbols. That is
probably what i got wrong with cable tests. I did all my testing with
it built in. But phylib can be built as a module. But that then
implies the core ethtool code cannot be built in, otherwise you get
undefined reference. So it was reworked to reference phylib via
phy_ethtool_phy_ops.

So as Russell says, if a function is only referenced within a module,
there is no need to export it, so keeping the kernel namespace clean.

Andrew