diff mbox series

[RFC,net-next,7/8] net: phylink: use legacy_pre_march2020

Message ID E1mpSbV-00BXp0-5d@rmk-PC.armlinux.org.uk (mailing list archive)
State RFC
Delegated to: Netdev Maintainers
Headers show
Series net: phylink: introduce legacy mode flag | expand

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Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 79 this patch: 79
netdev/cc_maintainers warning 1 maintainers not CCed: linux@armlinux.org.uk
netdev/build_clang success Errors and warnings before: 34 this patch: 34
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 83 this patch: 83
netdev/checkpatch warning WARNING: 'seperate' may be misspelled - perhaps 'separate'?
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Russell King (Oracle) Nov. 23, 2021, 10 a.m. UTC
Use the legacy flag to indicate whether we should operate in legacy
mode. This allows us to stop using the presence of a PCS as an
indicator to the age of the phylink user, and make PCS presence
optional.

Legacy mode involves:
1) calling mac_config() whenever the link comes up
2) calling mac_config() whenever the inband advertisement changes,
   possibly followed by a call to mac_an_restart()
3) making use of mac_an_restart()
4) making use of mac_pcs_get_state()

All the above functionality was moved to a seperate "PCS" block of
operations in March 2020.

Update the documents to indicate that the differences that this flag
makes.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 12 ++++++------
 include/linux/phylink.h   | 17 +++++++++++++++++
 2 files changed, 23 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 3603c024109a..a935655c39c0 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -742,7 +742,7 @@  static void phylink_mac_pcs_an_restart(struct phylink *pl)
 	    phylink_autoneg_inband(pl->cur_link_an_mode)) {
 		if (pl->pcs_ops)
 			pl->pcs_ops->pcs_an_restart(pl->pcs);
-		else
+		else if (pl->config->legacy_pre_march2020)
 			pl->mac_ops->mac_an_restart(pl->config);
 	}
 }
@@ -803,7 +803,7 @@  static int phylink_change_inband_advert(struct phylink *pl)
 	if (test_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state))
 		return 0;
 
-	if (!pl->pcs_ops) {
+	if (!pl->pcs_ops && pl->config->legacy_pre_march2020) {
 		/* Legacy method */
 		phylink_mac_config(pl, &pl->link_config);
 		phylink_mac_pcs_an_restart(pl);
@@ -854,7 +854,8 @@  static void phylink_mac_pcs_get_state(struct phylink *pl,
 
 	if (pl->pcs_ops)
 		pl->pcs_ops->pcs_get_state(pl->pcs, state);
-	else if (pl->mac_ops->mac_pcs_get_state)
+	else if (pl->mac_ops->mac_pcs_get_state &&
+		 pl->config->legacy_pre_march2020)
 		pl->mac_ops->mac_pcs_get_state(pl->config, state);
 	else
 		state->link = 0;
@@ -1024,12 +1025,11 @@  static void phylink_resolve(struct work_struct *w)
 			}
 			phylink_major_config(pl, false, &link_state);
 			pl->link_config.interface = link_state.interface;
-		} else if (!pl->pcs_ops) {
+		} else if (!pl->pcs_ops && pl->config->legacy_pre_march2020) {
 			/* The interface remains unchanged, only the speed,
 			 * duplex or pause settings have changed. Call the
 			 * old mac_config() method to configure the MAC/PCS
-			 * only if we do not have a PCS installed (an
-			 * unconverted user.)
+			 * only if we do not have a legacy MAC driver.
 			 */
 			phylink_mac_config(pl, &link_state);
 		}
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index d005b8e36048..a2f266cc3442 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -190,6 +190,10 @@  void validate(struct phylink_config *config, unsigned long *supported,
  * negotiation completion state in @state->an_complete, and link up state
  * in @state->link. If possible, @state->lp_advertising should also be
  * populated.
+ *
+ * Note: This is a legacy method. This function will not be called unless
+ * legacy_pre_march2020 is set in &struct phylink_config and there is no
+ * PCS attached.
  */
 void mac_pcs_get_state(struct phylink_config *config,
 		       struct phylink_link_state *state);
@@ -230,6 +234,15 @@  int mac_prepare(struct phylink_config *config, unsigned int mode,
  * guaranteed to be correct, and so any mac_config() implementation must
  * never reference these fields.
  *
+ * Note: For legacy March 2020 drivers (drivers with legacy_pre_march2020 set
+ * in their &phylnk_config and which don't have a PCS), this function will be
+ * called on each link up event, and to also change the in-band advert. For
+ * non-legacy drivers, it will only be called to reconfigure the MAC for a
+ * "major" change in e.g. interface mode. It will not be called for changes
+ * in speed, duplex or pause modes or to change the in-band advertisement.
+ * In any case, it is strongly preferred that speed, duplex and pause settings
+ * are handled in the mac_link_up() method and not in this method.
+ *
  * (this requires a rewrite - please refer to mac_link_up() for situations
  *  where the PCS and MAC are not tightly integrated.)
  *
@@ -314,6 +327,10 @@  int mac_finish(struct phylink_config *config, unsigned int mode,
 /**
  * mac_an_restart() - restart 802.3z BaseX autonegotiation
  * @config: a pointer to a &struct phylink_config.
+ *
+ * Note: This is a legacy method. This function will not be called unless
+ * legacy_pre_march2020 is set in &struct phylink_config and there is no
+ * PCS attached.
  */
 void mac_an_restart(struct phylink_config *config);