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| author | Marc Zyngier <marc.zyngier@arm.com> | 2015-09-30 13:05:17 +0200 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2015-10-09 23:16:57 +0200 |
| commit | 6d32ab2d8a982ffd46c4dcad9739292f57bc26de (patch) | |
| tree | 9acf0cba051715af0af4c43c32f279ded3b8d4ea /Documentation/arm64 | |
| parent | irqchip/gic: Warn if GICv3 system registers are enabled (diff) | |
| download | linux-6d32ab2d8a982ffd46c4dcad9739292f57bc26de.tar.xz linux-6d32ab2d8a982ffd46c4dcad9739292f57bc26de.zip | |
arm64: Update booting requirements for GICv3 in GICv2 mode
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.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'Documentation/arm64')
| -rw-r--r-- | Documentation/arm64/booting.txt | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/Documentation/arm64/booting.txt b/Documentation/arm64/booting.txt index 7d9d3c2286b2..369a4f48eb0d 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 |