Re: [PATCH v2 02/17] powerpc/cell: Move data segment faulting code out of cell platform

Aneesh Kumar K.V
2014-10-01T09:45:56Z

Michael Neuling <mikey@neuling.org> writes:

> From: Ian Munsie <imunsie@au1.ibm.com>
>
> __spu_trap_data_seg() currently contains code to determine the VSID and ESID
> required for a particular EA and mm struct.
>
> This code is generically useful for other co-processors. This moves the code
> of the cell platform so it can be used by other powerpc code. It also adds 1TB
> segment handling which Cell didn't have.
>
> Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
> Signed-off-by: Michael Neuling <mikey@neuling.org>
> ---
> arch/powerpc/include/asm/mmu-hash64.h | 7 ++++-
> arch/powerpc/mm/copro_fault.c | 48 ++++++++++++++++++++++++++++++++++
> arch/powerpc/mm/slb.c | 3 ---
> arch/powerpc/platforms/cell/spu_base.c | 41 +++--------------------------
> 4 files changed, 58 insertions(+), 41 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/mmu-hash64.h b/arch/powerpc/include/asm/mmu-hash64.h
> index d765144..6d0b7a2 100644
> --- a/arch/powerpc/include/asm/mmu-hash64.h
> +++ b/arch/powerpc/include/asm/mmu-hash64.h
> @@ -189,7 +189,12 @@ static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize)
> #define LP_MASK(i) ((0xFF >> (i)) << LP_SHIFT)
>
> #ifndef __ASSEMBLY__
> -
> +static inline int slb_vsid_shift(int ssize)
> +{
> + if (ssize == MMU_SEGSIZE_256M)
> + return SLB_VSID_SHIFT;
> + return SLB_VSID_SHIFT_1T;
> +}
> static inline int segment_shift(int ssize)
> {
> if (ssize == MMU_SEGSIZE_256M)
> diff --git a/arch/powerpc/mm/copro_fault.c b/arch/powerpc/mm/copro_fault.c
> index ba7df14..b865697 100644
> --- a/arch/powerpc/mm/copro_fault.c
> +++ b/arch/powerpc/mm/copro_fault.c
> @@ -90,3 +90,51 @@ out_unlock:
> return ret;
> }
> EXPORT_SYMBOL_GPL(copro_handle_mm_fault);
> +
> +int copro_data_segment(struct mm_struct *mm, u64 ea, u64 *esid, u64 *vsid)
> +{
> + int psize, ssize;
> +
> + *esid = (ea & ESID_MASK) | SLB_ESID_V;
> +
> + switch (REGION_ID(ea)) {
> + case USER_REGION_ID:
> + pr_devel("copro_data_segment: 0x%llx -- USER_REGION_ID\n", ea);
> +#ifdef CONFIG_PPC_MM_SLICES
> + psize = get_slice_psize(mm, ea);
> +#else
> + psize = mm->context.user_psize;
> +#endif

We don't really need that as explained in last review.

-aneesh