diff options
| author | Alex Hung | 2020-03-04 15:55:29 -0700 |
|---|---|---|
| committer | Rafael J. Wysocki | 2020-03-14 10:36:49 +0100 |
| commit | 1ffb8d032d03d686e3b06378780944608cc77906 (patch) | |
| tree | b886824b16cc977eef905509f927271d8e4f4478 | |
| parent | fa0fca68e1e64bc53fcb7cfd4bfac27c1b14a955 (diff) | |
acpi/x86: add a kernel parameter to disable ACPI BGRT
BGRT is for displaying seamless OEM logo from booting to login screen;
however, this mechanism does not always work well on all configurations
and the OEM logo can be displayed multiple times. This looks worse than
without BGRT enabled.
This patch adds a kernel parameter to disable BGRT in boot time. This is
easier than re-compiling a kernel with CONFIG_ACPI_BGRT disabled.
Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/acpi/boot.c | 10 |
2 files changed, 12 insertions, 1 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index c07815d230bc..83ba095b3cde 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -450,6 +450,9 @@ bert_disable [ACPI] Disable BERT OS support on buggy BIOSes. + bgrt_disable [ACPI][X86] + Disable BGRT to avoid flickering OEM logo. + bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards) bttv.radio= Most important insmod options are available as kernel args too. diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 04205ce127a1..d1757ceca8ae 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -45,6 +45,7 @@ EXPORT_SYMBOL(acpi_disabled); #define PREFIX "ACPI: " int acpi_noirq; /* skip ACPI IRQ initialization */ +int acpi_nobgrt; /* skip ACPI BGRT */ int acpi_pci_disabled; /* skip ACPI PCI scan and IRQ initialization */ EXPORT_SYMBOL(acpi_pci_disabled); @@ -1619,7 +1620,7 @@ int __init acpi_boot_init(void) acpi_process_madt(); acpi_table_parse(ACPI_SIG_HPET, acpi_parse_hpet); - if (IS_ENABLED(CONFIG_ACPI_BGRT)) + if (IS_ENABLED(CONFIG_ACPI_BGRT) && !acpi_nobgrt) acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt); if (!acpi_noirq) @@ -1671,6 +1672,13 @@ static int __init parse_acpi(char *arg) } early_param("acpi", parse_acpi); +static int __init parse_acpi_bgrt(char *arg) +{ + acpi_nobgrt = true; + return 0; +} +early_param("bgrt_disable", parse_acpi_bgrt); + /* FIXME: Using pci= for an ACPI parameter is a travesty. */ static int __init parse_pci(char *arg) { |