diff options
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/kernel/acpi.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index fd1917336d3a..a73b87ac815c 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -45,6 +45,7 @@ EXPORT_SYMBOL(acpi_pci_disabled); static bool param_acpi_off __initdata; static bool param_acpi_on __initdata; static bool param_acpi_force __initdata; +static bool param_acpi_nospcr __initdata; static int __init parse_acpi(char *arg) { @@ -58,6 +59,8 @@ static int __init parse_acpi(char *arg) param_acpi_on = true; else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */ param_acpi_force = true; + else if (strcmp(arg, "nospcr") == 0) /* disable SPCR as default console */ + param_acpi_nospcr = true; else return -EINVAL; /* Core will print when we return error */ @@ -237,7 +240,20 @@ done: acpi_put_table(facs); } #endif - acpi_parse_spcr(earlycon_acpi_spcr_enable, true); + + /* + * For varying privacy and security reasons, sometimes need + * to completely silence the serial console output, and only + * enable it when needed. + * But there are many existing systems that depend on this + * behaviour, use acpi=nospcr to disable console in ACPI SPCR + * table as default serial console. + */ + acpi_parse_spcr(earlycon_acpi_spcr_enable, + !param_acpi_nospcr); + pr_info("Use ACPI SPCR as default console: %s\n", + param_acpi_nospcr ? "No" : "Yes"); + if (IS_ENABLED(CONFIG_ACPI_BGRT)) acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt); } |