The kernel driver for the Interrupt Translation Service of ARM's Generic Interrupt Controller version 3 (sys/arm64/arm64/gicv3_its.c) reads the GICR_TYPER memory-mapped register of the redistributor in its its_init_cpu() function: /* Check if the ITS is enabled on this CPU */ if ((gic_r_read_4(gicv3, GICR_TYPER) & GICR_TYPER_PLPIS) == 0) ... This is a 32-bit read. However, GICR_TYPER is a 64-bit register and the GICv3 specification ([1], §11.1.3) only requires that such accesses be supported on systems with at least one core supporting Aarch32. By contrast, 64-bit reads are always supported. I suggest extending the read to 64 bits. By the way, the main GICv3 driver (sys/arm64/arm64/gic_v3.c) also reads GICR_TYPER, and it does so with bus_read_8(). This issue showed up on a software implementation of the ITS (hypervisor) that expected a 64-bit read. [1] https://developer.arm.com/documentation/ihi0069/latest
A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=1896a0094317c80d46beff5ad42b68215513c996 commit 1896a0094317c80d46beff5ad42b68215513c996 Author: Andrew Turner <andrew@FreeBSD.org> AuthorDate: 2021-09-15 09:13:41 +0000 Commit: Andrew Turner <andrew@FreeBSD.org> CommitDate: 2021-09-15 09:13:41 +0000 Use a 64 bit read to access GICR_TYPER The GICv3 ITS only needs to implement 32 bit access to the GICR_TYPER when the CPU implements AArch32. As this may not always be the case use a 64 bit read when checking if the ITS is enabled on the CPU. PR: 258217 Reported by: Olivier Delande <olivier.delande@provenrun.com> Sponsored by: The FreeBSD Foundation sys/arm64/arm64/gicv3_its.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Hey there! I've been able to boot FreeBSD 13.0-RELEASE arm64.aarch64 in UTM on M1 MBP, however FreeBSD 14.0-CURRENT does not boot. I get a kernel panic. Unfortunately I was not able to copy the console, so here's a screenshoot: https://antranigv.am/misc/freebsd-arm.jpg I feel like this issue is connected to this bug, let me know if my hunch is correct :) Thank you.
A commit in branch stable/13 references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=00c276a2502488f4198dcec4bf1a6d22159e2b62 commit 00c276a2502488f4198dcec4bf1a6d22159e2b62 Author: Andrew Turner <andrew@FreeBSD.org> AuthorDate: 2021-09-15 09:13:41 +0000 Commit: Andrew Turner <andrew@FreeBSD.org> CommitDate: 2021-10-11 10:50:42 +0000 Use a 64 bit read to access GICR_TYPER The GICv3 ITS only needs to implement 32 bit access to the GICR_TYPER when the CPU implements AArch32. As this may not always be the case use a 64 bit read when checking if the ITS is enabled on the CPU. PR: 258217 Reported by: Olivier Delande <olivier.delande@provenrun.com> Sponsored by: The FreeBSD Foundation (cherry picked from commit 1896a0094317c80d46beff5ad42b68215513c996) sys/arm64/arm64/gicv3_its.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)