The current requirements do not describe the case where a GICv3 system gets booted with system register access disabled, and expect the kernel to drive GICv3 in GICv2 mode.
Describe the expected settings for that particular case. Signed-off-by: Marc Zyngier <marc.zyng...@arm.com> --- Documentation/arm64/booting.txt | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/Documentation/arm64/booting.txt b/Documentation/arm64/booting.txt index 7d9d3c2..369a4f4 100644 --- a/Documentation/arm64/booting.txt +++ b/Documentation/arm64/booting.txt @@ -173,13 +173,22 @@ Before jumping into the kernel, the following conditions must be met: the kernel image will be entered must be initialised by software at a higher exception level to prevent execution in an UNKNOWN state. - For systems with a GICv3 interrupt controller: + For systems with a GICv3 interrupt controller to be used in v3 mode: - If EL3 is present: ICC_SRE_EL3.Enable (bit 3) must be initialiased to 0b1. ICC_SRE_EL3.SRE (bit 0) must be initialised to 0b1. - If the kernel is entered at EL1: ICC.SRE_EL2.Enable (bit 3) must be initialised to 0b1 ICC_SRE_EL2.SRE (bit 0) must be initialised to 0b1. + - The DT or ACPI tables must describe a GICv3 interrupt controller. + + For systems with a GICv3 interrupt controller to be used in + compatibility (v2) mode: + - If EL3 is present: + ICC_SRE_EL3.SRE (bit 0) must be initialised to 0b0. + - If the kernel is entered at EL1: + ICC_SRE_EL2.SRE (bit 0) must be initialised to 0b0. + - The DT or ACPI tables must describe a GICv2 interrupt controller. The requirements described above for CPU mode, caches, MMUs, architected timers, coherency and system registers apply to all CPUs. All CPUs must -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/