diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 189df0bcab99..c6859b94aaa7 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -431,8 +431,10 @@ and is between 256 and 4096 characters. It is defined in the file over the 8254 in addition to over the IO-APIC. The kernel tries to set a sensible default. - hpet= [X86-32,HPET] option to disable HPET and use PIT. - Format: disable + hpet= [X86-32,HPET] option to control HPET usage + Format: { enable (default) | disable | force } + disable: disable HPET and use PIT instead + force: allow force enabled of undocumented chips (ICH4, VIA) com20020= [HW,NET] ARCnet - COM20020 chipset Format: diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index f8367074da0d..22d8f00c80dc 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -69,12 +69,15 @@ static inline void hpet_clear_mapping(void) * HPET command line enable / disable */ static int boot_hpet_disable; +int hpet_force_user; static int __init hpet_setup(char* str) { if (str) { if (!strncmp("disable", str, 7)) boot_hpet_disable = 1; + if (!strncmp("force", str, 5)) + hpet_force_user = 1; } return 1; } diff --git a/include/asm-x86/hpet.h b/include/asm-x86/hpet.h index d4ab6db050b6..4f51519fc199 100644 --- a/include/asm-x86/hpet.h +++ b/include/asm-x86/hpet.h @@ -64,6 +64,7 @@ /* hpet memory map physical address */ extern unsigned long hpet_address; extern unsigned long force_hpet_address; +extern int hpet_force_user; extern int is_hpet_enabled(void); extern int hpet_enable(void); extern unsigned long hpet_readl(unsigned long a);