On 19 January 2015 at 11:42, Catalin Marinas <catalin.marinas@xxxxxxx> wrote: > On Wed, Jan 14, 2015 at 03:04:52PM +0000, Hanjun Guo wrote: >> From: Al Stone <al.stone@xxxxxxxxxx> >> >> Introduce one early parameters "off" and "force" for "acpi", acpi=off >> will be the default behavior for ARM64, so introduce acpi=force to >> enable ACPI on ARM64. >> >> Disable ACPI before early parameters parsed, and enable it to pass >> "acpi=force" if people want use ACPI on ARM64. This ensures DT be >> the prefer one if ACPI table and DT both are provided at this moment. > [...] >> --- a/arch/arm64/kernel/setup.c >> +++ b/arch/arm64/kernel/setup.c >> @@ -62,6 +62,7 @@ >> #include <asm/memblock.h> >> #include <asm/psci.h> >> #include <asm/efi.h> >> +#include <asm/acpi.h> >> >> unsigned int processor_id; >> EXPORT_SYMBOL(processor_id); >> @@ -388,6 +389,8 @@ void __init setup_arch(char **cmdline_p) >> early_fixmap_init(); >> early_ioremap_init(); >> >> + disable_acpi(); >> + >> parse_early_param(); >> >> /* > > Did we get to any conclusion here? DT being the preferred one is fine > when both DT and ACPI are present but do we still want the kernel to > ignore ACPI altogether if DT is not present? It's a bit harder to detect > the presence of DT at this point since the EFI_STUB added one already. I > guess we could move the "acpi=force" argument passing to EFI_STUB if no > DT is present at boot. > Since the EFI stub populates the /chosen node in DT, I would prefer for it to add a property there to indicate whether it created the DT from scratch rather than adding ACPI specific stuff in there (even if it is just a string to concatenate) -- Ard. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
