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Re: [RFC v6 15/62] powerpc: helper functions to initialize AMR, IAMR and UMOR registers

From Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Newsgroups linux.kernel
Subject Re: [RFC v6 15/62] powerpc: helper functions to initialize AMR, IAMR and UMOR registers
Date 2017-07-27 22:50 +0200
Message-ID <u7XTl-2wS-21@gated-at.bofh.it> (permalink)
References <u3ISR-1St-3@gated-at.bofh.it> <u3ISS-1St-23@gated-at.bofh.it>
Organization linux.* mail to news gateway

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Ram Pai <linuxram@us.ibm.com> writes:

> Introduce helper functions that can initialize the bits in the AMR,
> IAMR and UMOR register; the bits that correspond to the given pkey.
>
> Signed-off-by: Ram Pai <linuxram@us.ibm.com>

s/UMOR/UAMOR/ here and in the subject as well.

> --- a/arch/powerpc/mm/pkeys.c
> +++ b/arch/powerpc/mm/pkeys.c
> @@ -16,3 +16,47 @@
>  #include <linux/pkeys.h>                /* PKEY_*                       */
>
>  bool pkey_inited;
> +#define pkeyshift(pkey) ((arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY)
> +
> +static inline void init_amr(int pkey, u8 init_bits)
> +{
> +	u64 new_amr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
> +	u64 old_amr = read_amr() & ~((u64)(0x3ul) << pkeyshift(pkey));
> +
> +	write_amr(old_amr | new_amr_bits);
> +}
> +
> +static inline void init_iamr(int pkey, u8 init_bits)
> +{
> +	u64 new_iamr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
> +	u64 old_iamr = read_iamr() & ~((u64)(0x3ul) << pkeyshift(pkey));
> +
> +	write_amr(old_iamr | new_iamr_bits);
> +}

init_iamr should call write_iamr, not write_amr.

-- 
Thiago Jung Bauermann
IBM Linux Technology Center

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Re: [RFC v6 15/62] powerpc: helper functions to initialize AMR, IAMR and UMOR registers Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> - 2017-07-27 22:50 +0200
  Re: [RFC v6 15/62] powerpc: helper functions to initialize AMR, IAMR  and UMOR registers Ram Pai <linuxram@us.ibm.com> - 2017-07-30 02:40 +0200

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