| Message ID | 1464142194-32766-1-git-send-email-Wei.Chen@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
Hi Wei, Title: "Fix the MPIDR_HWID_MASK value for ARM64". On 25/05/16 03:09, Wei Chen wrote: > Current MPIDR_HWID_MASK is using the bit definition of ARM32 MPIDR. s/Current/Currently/ > This value is not correct while Xen is running on ARM64. I think s/while/when/ > Now, we add a correct value for this marco on ARM64. But this value s/marco/macro/ > is not a valid 64-bit immediate which can be encoded in mov instruction. > So we have to use ldr to load this value to register. You need to explain what is the valid value, i.e there is 4 level of affinity whilst AArch32 has only 3. It would be good to mention the spec too. > > Signed-off-by: Wei Chen <Wei.Chen@linaro.org> > --- > xen/arch/arm/arm64/head.S | 2 +- > xen/include/asm-arm/processor.h | 4 ++++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S > index d5831f2..3090beb 100644 > --- a/xen/arch/arm/arm64/head.S > +++ b/xen/arch/arm/arm64/head.S > @@ -270,7 +270,7 @@ common_start: > tbz x0, _MPIDR_SMP, 1f /* Multiprocessor extension not supported? */ > tbnz x0, _MPIDR_UP, 1f /* Uniprocessor system? */ > > - mov x13, #(~MPIDR_HWID_MASK) > + ldr x13, =(~MPIDR_HWID_MASK) > bic x24, x0, x13 /* Mask out flags to get CPU ID */ > 1: > > diff --git a/xen/include/asm-arm/processor.h b/xen/include/asm-arm/processor.h > index b4cce7e..284ad6a 100644 > --- a/xen/include/asm-arm/processor.h > +++ b/xen/include/asm-arm/processor.h > @@ -18,7 +18,11 @@ > #define MPIDR_SMP (_AC(1,U) << _MPIDR_SMP) > #define MPIDR_AFF0_SHIFT (0) > #define MPIDR_AFF0_MASK (_AC(0xff,U) << MPIDR_AFF0_SHIFT) > +#ifdef CONFIG_ARM_64 > +#define MPIDR_HWID_MASK _AC(0xff00ffffff,UL) > +#else > #define MPIDR_HWID_MASK _AC(0xffffff,U) > +#endif > #define MPIDR_INVALID (~MPIDR_HWID_MASK) > #define MPIDR_LEVEL_BITS (8) > > Regards,
diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S index d5831f2..3090beb 100644 --- a/xen/arch/arm/arm64/head.S +++ b/xen/arch/arm/arm64/head.S @@ -270,7 +270,7 @@ common_start: tbz x0, _MPIDR_SMP, 1f /* Multiprocessor extension not supported? */ tbnz x0, _MPIDR_UP, 1f /* Uniprocessor system? */ - mov x13, #(~MPIDR_HWID_MASK) + ldr x13, =(~MPIDR_HWID_MASK) bic x24, x0, x13 /* Mask out flags to get CPU ID */ 1: diff --git a/xen/include/asm-arm/processor.h b/xen/include/asm-arm/processor.h index b4cce7e..284ad6a 100644 --- a/xen/include/asm-arm/processor.h +++ b/xen/include/asm-arm/processor.h @@ -18,7 +18,11 @@ #define MPIDR_SMP (_AC(1,U) << _MPIDR_SMP) #define MPIDR_AFF0_SHIFT (0) #define MPIDR_AFF0_MASK (_AC(0xff,U) << MPIDR_AFF0_SHIFT) +#ifdef CONFIG_ARM_64 +#define MPIDR_HWID_MASK _AC(0xff00ffffff,UL) +#else #define MPIDR_HWID_MASK _AC(0xffffff,U) +#endif #define MPIDR_INVALID (~MPIDR_HWID_MASK) #define MPIDR_LEVEL_BITS (8)
Current MPIDR_HWID_MASK is using the bit definition of ARM32 MPIDR. This value is not correct while Xen is running on ARM64. Now, we add a correct value for this marco on ARM64. But this value is not a valid 64-bit immediate which can be encoded in mov instruction. So we have to use ldr to load this value to register. Signed-off-by: Wei Chen <Wei.Chen@linaro.org> --- xen/arch/arm/arm64/head.S | 2 +- xen/include/asm-arm/processor.h | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-)