From 42d36969e307cf0c7a523755a6f66cecb69cd32c Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Thu, 3 Jul 2025 12:25:20 +0200 Subject: [PATCH] docs: arm64: gic-v5: Document booting requirements for GICv5 Document the requirements for booting a kernel on a system implementing a GICv5 interrupt controller. Specifically, other than DT/ACPI providing the required firmware representation, define what traps must be disabled if the kernel is booted at EL1 on a system where EL2 is implemented. Signed-off-by: Lorenzo Pieralisi Reviewed-by: Marc Zyngier Cc: Will Deacon Cc: Catalin Marinas Cc: Marc Zyngier Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20250703-gicv5-host-v7-30-12e71f1b3528@kernel.org Signed-off-by: Marc Zyngier --- Documentation/arch/arm64/booting.rst | 41 ++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst index ee9b790c0d72f..83e037351f6dc 100644 --- a/Documentation/arch/arm64/booting.rst +++ b/Documentation/arch/arm64/booting.rst @@ -223,6 +223,47 @@ Before jumping into the kernel, the following conditions must be met: - SCR_EL3.HCE (bit 8) must be initialised to 0b1. + For systems with a GICv5 interrupt controller to be used in v5 mode: + + - If the kernel is entered at EL1 and EL2 is present: + + - ICH_HFGRTR_EL2.ICC_PPI_ACTIVERn_EL1 (bit 20) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_PPI_PRIORITYRn_EL1 (bit 19) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_PPI_PENDRn_EL1 (bit 18) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_PPI_ENABLERn_EL1 (bit 17) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_PPI_HMRn_EL1 (bit 16) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_IAFFIDR_EL1 (bit 7) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_ICSR_EL1 (bit 6) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_PCR_EL1 (bit 5) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_HPPIR_EL1 (bit 4) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_HAPR_EL1 (bit 3) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_CR0_EL1 (bit 2) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_IDRn_EL1 (bit 1) must be initialised to 0b1. + - ICH_HFGRTR_EL2.ICC_APR_EL1 (bit 0) must be initialised to 0b1. + + - ICH_HFGWTR_EL2.ICC_PPI_ACTIVERn_EL1 (bit 20) must be initialised to 0b1. + - ICH_HFGWTR_EL2.ICC_PPI_PRIORITYRn_EL1 (bit 19) must be initialised to 0b1. + - ICH_HFGWTR_EL2.ICC_PPI_PENDRn_EL1 (bit 18) must be initialised to 0b1. + - ICH_HFGWTR_EL2.ICC_PPI_ENABLERn_EL1 (bit 17) must be initialised to 0b1. + - ICH_HFGWTR_EL2.ICC_ICSR_EL1 (bit 6) must be initialised to 0b1. + - ICH_HFGWTR_EL2.ICC_PCR_EL1 (bit 5) must be initialised to 0b1. + - ICH_HFGWTR_EL2.ICC_CR0_EL1 (bit 2) must be initialised to 0b1. + - ICH_HFGWTR_EL2.ICC_APR_EL1 (bit 0) must be initialised to 0b1. + + - ICH_HFGITR_EL2.GICRCDNMIA (bit 10) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICRCDIA (bit 9) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDDI (bit 8) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDEOI (bit 7) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDHM (bit 6) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDRCFG (bit 5) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDPEND (bit 4) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDAFF (bit 3) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDPRI (bit 2) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDDIS (bit 1) must be initialised to 0b1. + - ICH_HFGITR_EL2.GICCDEN (bit 0) must be initialised to 0b1. + + - The DT or ACPI tables must describe a GICv5 interrupt controller. + For systems with a GICv3 interrupt controller to be used in v3 mode: - If EL3 is present: -- 2.47.2