The branch stable/12 has been updated by kevans: URL: https://cgit.FreeBSD.org/src/commit/?id=354d310fe9871df0cbc3edfd5c3ef61ad39acfbf
commit 354d310fe9871df0cbc3edfd5c3ef61ad39acfbf Author: Kyle Evans <[email protected]> AuthorDate: 2022-03-19 03:03:44 +0000 Commit: Kyle Evans <[email protected]> CommitDate: 2022-09-17 19:29:35 +0000 arm64: gic: disable the ITS if it's enabled prior to configuration The ITS is defined to be disabled on a warm reset, but we may be coming in via another kernel/hypervisor type setup where the ITS has been previously configured then relinquished to the next kernel in the chain. If it's enabled, the later configuration of GITS_BASER will almost certainly fail -- clear it to prevent that. Reviewed by: andrew Sponsored by: Ampere Computing Submitted by: Klara, Inc. (cherry picked from commit 1236b04bb7045e541b2343543e356273db20ee56) --- sys/arm64/arm64/gicv3_its.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/sys/arm64/arm64/gicv3_its.c b/sys/arm64/arm64/gicv3_its.c index 6521752b5a62..465d01558ae2 100644 --- a/sys/arm64/arm64/gicv3_its.c +++ b/sys/arm64/arm64/gicv3_its.c @@ -784,7 +784,7 @@ gicv3_its_attach(device_t dev) { struct gicv3_its_softc *sc; const char *name; - uint32_t iidr; + uint32_t ctlr, iidr; int domain, err, i, rid; sc = device_get_softc(dev); @@ -813,6 +813,18 @@ gicv3_its_attach(device_t dev) } } + /* + * GIT_CTLR_EN is mandated to reset to 0 on a Warm reset, but we may be + * coming in via, for instance, a kexec/kboot style setup where a + * previous kernel has configured then relinquished control. Clear it + * so that we can reconfigure GITS_BASER*. + */ + ctlr = gic_its_read_4(sc, GITS_CTLR); + if ((ctlr & GITS_CTLR_EN) != 0) { + ctlr &= ~GITS_CTLR_EN; + gic_its_write_4(sc, GITS_CTLR, ctlr); + } + /* Allocate the private tables */ err = gicv3_its_table_init(dev, sc); if (err != 0) @@ -845,8 +857,7 @@ gicv3_its_attach(device_t dev) sc->sc_its_cols[cpu] = NULL; /* Enable the ITS */ - gic_its_write_4(sc, GITS_CTLR, - gic_its_read_4(sc, GITS_CTLR) | GITS_CTLR_EN); + gic_its_write_4(sc, GITS_CTLR, ctlr | GITS_CTLR_EN); /* Create the LPI configuration table */ gicv3_its_conftable_init(sc);
