git: 964b3408fa87 - main - dpaa2: defer link_state updates until we are up

From: Bjoern A. Zeeb <bz_at_FreeBSD.org>
Date: Fri, 17 Nov 2023 12:20:32 UTC
The branch main has been updated by bz:

URL: https://cgit.FreeBSD.org/src/commit/?id=964b3408fa872178aacf58f2d84dc43564ec0aa7

commit 964b3408fa872178aacf58f2d84dc43564ec0aa7
Author:     Bjoern A. Zeeb <bz@FreeBSD.org>
AuthorDate: 2023-11-17 00:47:11 +0000
Commit:     Bjoern A. Zeeb <bz@FreeBSD.org>
CommitDate: 2023-11-17 12:20:03 +0000

    dpaa2: defer link_state updates until we are up
    
    dpaa2_ni_media_change() was called in early setup stages, before we
    were fully setup.  That lead to internal driver state being all synched
    and fine but hardware state was lost/never setup corrently.
    
    Introduce dpaa2_ni_media_change_locked() so we can avoid reccursive
    locking and call "dpaa2_ni_media_change()" instead of mii_mediachg()
    as the latter does not setup our state there either.
    
    In order for this all to work, call if_setdrvflagbits() just before
    rather than after the above.
    
    Also remove an unecessary direct call to dpaa2_ni_miibus_statchg()
    which mii_mediachg() will trigger anyway.
    
    This all fixes a problem [1] that one had to lose the link (either
    unplugging/replugging the cable or using ifconfig media none;
    ifconfig media auto) to re-trigger the all updates and get the
    full state programmed when hardware expected.
    
    MFC after:      3 days
    GH-Issue:       https://github.com/mcusim/freebsd-src/issues/21 [1]
    Reviewed by:    dsl, dch
    Differential Revision: https://reviews.freebsd.org/D42643
---
 sys/dev/dpaa2/dpaa2_ni.c | 46 ++++++++++++++++++++++++++++++++++++----------
 1 file changed, 36 insertions(+), 10 deletions(-)

diff --git a/sys/dev/dpaa2/dpaa2_ni.c b/sys/dev/dpaa2/dpaa2_ni.c
index b274d5670d5f..a9e6aa120549 100644
--- a/sys/dev/dpaa2/dpaa2_ni.c
+++ b/sys/dev/dpaa2/dpaa2_ni.c
@@ -116,6 +116,9 @@
 	mtx_assert(&(__sc)->lock, MA_OWNED);	\
 	mtx_unlock(&(__sc)->lock);		\
 } while (0)
+#define	DPNI_LOCK_ASSERT(__sc) do {		\
+	mtx_assert(&(__sc)->lock, MA_OWNED);	\
+} while (0)
 
 #define DPAA2_TX_RING(sc, chan, tc) \
 	(&(sc)->channels[(chan)]->txc_queue.tx_rings[(tc)])
@@ -2269,6 +2272,16 @@ dpaa2_ni_miibus_statchg(device_t dev)
 	if (sc->fixed_link || sc->mii == NULL) {
 		return;
 	}
+	if ((if_getdrvflags(sc->ifp) & IFF_DRV_RUNNING) == 0) {
+		/*
+		 * We will receive calls and adjust the changes but
+		 * not have setup everything (called before dpaa2_ni_init()
+		 * really).  This will then setup the link and internal
+		 * sc->link_state and not trigger the update once needed,
+		 * so basically dpmac never knows about it.
+		 */
+		return;
+	}
 
 	/*
 	 * Note: ifp link state will only be changed AFTER we are called so we
@@ -2344,23 +2357,33 @@ err_exit:
  * @brief Callback function to process media change request.
  */
 static int
-dpaa2_ni_media_change(if_t ifp)
+dpaa2_ni_media_change_locked(struct dpaa2_ni_softc *sc)
 {
-	struct dpaa2_ni_softc *sc = if_getsoftc(ifp);
 
-	DPNI_LOCK(sc);
+	DPNI_LOCK_ASSERT(sc);
 	if (sc->mii) {
 		mii_mediachg(sc->mii);
 		sc->media_status = sc->mii->mii_media.ifm_media;
 	} else if (sc->fixed_link) {
-		if_printf(ifp, "%s: can't change media in fixed mode\n",
+		if_printf(sc->ifp, "%s: can't change media in fixed mode\n",
 		    __func__);
 	}
-	DPNI_UNLOCK(sc);
 
 	return (0);
 }
 
+static int
+dpaa2_ni_media_change(if_t ifp)
+{
+	struct dpaa2_ni_softc *sc = if_getsoftc(ifp);
+	int error;
+
+	DPNI_LOCK(sc);
+	error = dpaa2_ni_media_change_locked(sc);
+	DPNI_UNLOCK(sc);
+	return (error);
+}
+
 /**
  * @brief Callback function to process media status request.
  */
@@ -2443,17 +2466,20 @@ dpaa2_ni_init(void *arg)
 	}
 
 	DPNI_LOCK(sc);
+	/* Announce we are up and running and can queue packets. */
+	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, IFF_DRV_OACTIVE);
+
 	if (sc->mii) {
-		mii_mediachg(sc->mii);
+		/*
+		 * mii_mediachg() will trigger a call into
+		 * dpaa2_ni_miibus_statchg() to setup link state.
+		 */
+		dpaa2_ni_media_change_locked(sc);
 	}
 	callout_reset(&sc->mii_callout, hz, dpaa2_ni_media_tick, sc);
 
-	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, IFF_DRV_OACTIVE);
 	DPNI_UNLOCK(sc);
 
-	/* Force link-state update to initilize things. */
-	dpaa2_ni_miibus_statchg(dev);
-
 	(void)DPAA2_CMD_NI_CLOSE(dev, child, DPAA2_CMD_TK(&cmd, ni_token));
 	(void)DPAA2_CMD_RC_CLOSE(dev, child, DPAA2_CMD_TK(&cmd, rc_token));
 	return;