On Fri, Jan 23, 2015 at 05:54:45PM +0000, Russell King - ARM Linux wrote: > On Fri, Jan 23, 2015 at 05:50:39PM +0000, Will Deacon wrote: > > On Fri, Jan 23, 2015 at 05:31:54PM +0000, Andy Whitcroft wrote: > > > diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c > > > index f1dbca7..425cf78 100644 > > > --- a/arch/arm64/kernel/psci.c > > > +++ b/arch/arm64/kernel/psci.c > > > @@ -113,9 +113,14 @@ static void psci_power_state_unpack(u32 power_state, > > > * The following two functions are invoked via the invoke_psci_fn pointer > > > * and will not be inlined, allowing us to piggyback on the AAPCS. > > > */ > > > -static noinline int __invoke_psci_fn_hvc(u64 function_id, u64 arg0, u64 > > > arg1, > > > - u64 arg2) > > > +static noinline int __invoke_psci_fn_hvc(u64 _function_id, u64 _arg0, > > > + u64 _arg1, u64 _arg2) > > > { > > > + register u64 function_id asm("x0") = _function_id; > > > + register u64 arg0 asm("x1") = _arg0; > > > + register u64 arg1 asm("x2") = _arg1; > > > + register u64 arg2 asm("x3") = _arg2; > > > + > > > > Given that we've already been bitten by the compiler, I think we should > > just bite the bullet and implement these two functions in assembly in a > > separate file rather than rely on register variables doing what we want. > > The alternative is a naked function.
I wondered about that, but the gcc docs say that you can't then provide operands to the asm block, which would mean removing the __asmeq checks altogether (which terrifies me!). Will -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/