diff options
| author | Liu Wei <liuwei09@cestc.cn> | 2024-06-25 11:05:04 +0800 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2024-07-04 16:33:13 +0100 |
| commit | f5a4af3c752704272e9094466e66e21d4ee4e414 (patch) | |
| tree | cdb1063521df7e587b89d315902147d863c9f5a6 /Documentation | |
| parent | bfe3f0df3e3c0afdbe147d2479fe9aee4d0683e9 (diff) | |
ACPI: Add acpi=nospcr to disable ACPI SPCR as default console on ARM64
For varying privacy and security reasons, sometimes we would like to
completely silence the _serial_ console, and only enable it when needed.
But there are many existing systems that depend on this _serial_ console,
so add acpi=nospcr to disable console in ACPI SPCR table as default
_serial_ console.
Signed-off-by: Liu Wei <liuwei09@cestc.cn>
Suggested-by: Prarit Bhargava <prarit@redhat.com>
Suggested-by: Will Deacon <will@kernel.org>
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Prarit Bhargava <prarit@redhat.com>
Link: https://lore.kernel.org/r/20240625030504.58025-1-liuwei09@cestc.cn
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index b600df82669d..68d8acc38c82 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -12,7 +12,7 @@ acpi= [HW,ACPI,X86,ARM64,RISCV64,EARLY] Advanced Configuration and Power Interface Format: { force | on | off | strict | noirq | rsdt | - copy_dsdt } + copy_dsdt | nospcr } force -- enable ACPI if default was off on -- enable ACPI but allow fallback to DT [arm64,riscv64] off -- disable ACPI if default was on @@ -21,8 +21,12 @@ strictly ACPI specification compliant. rsdt -- prefer RSDT over (default) XSDT copy_dsdt -- copy DSDT to memory - For ARM64 and RISCV64, ONLY "acpi=off", "acpi=on" or - "acpi=force" are available + nospcr -- disable console in ACPI SPCR table as + default _serial_ console on ARM64 + For ARM64, ONLY "acpi=off", "acpi=on", "acpi=force" or + "acpi=nospcr" are available + For RISCV64, ONLY "acpi=off", "acpi=on" or "acpi=force" + are available See also Documentation/power/runtime_pm.rst, pci=noacpi |