From 4d70b698f9575cea7fa52e1d8f5020beca869907 Mon Sep 17 00:00:00 2001 From: Ram Pai Date: Thu, 18 Jan 2018 17:50:27 -0800 Subject: powerpc: helper functions to initialize AMR, IAMR and UAMOR registers Introduce helper functions that can initialize the bits in the AMR, IAMR and UAMOR register; the bits that correspond to the given pkey. Reviewed-by: Thiago Jung Bauermann Signed-off-by: Ram Pai Signed-off-by: Michael Ellerman --- arch/powerpc/mm/pkeys.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c index afa6d0d63f32..0cfe901594c7 100644 --- a/arch/powerpc/mm/pkeys.c +++ b/arch/powerpc/mm/pkeys.c @@ -12,6 +12,10 @@ bool pkey_execute_disable_supported; int pkeys_total; /* Total pkeys as per device tree */ u32 initial_allocation_mask; /* Bits set for reserved keys */ +#define AMR_BITS_PER_PKEY 2 +#define PKEY_REG_BITS (sizeof(u64)*8) +#define pkeyshift(pkey) (PKEY_REG_BITS - ((pkey+1) * AMR_BITS_PER_PKEY)) + int pkey_initialize(void) { int os_reserved, i; @@ -103,3 +107,46 @@ static inline void write_uamor(u64 value) { mtspr(SPRN_UAMOR, value); } + +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 & 0x1UL) << pkeyshift(pkey)); + u64 old_iamr = read_iamr() & ~((u64)(0x1ul) << pkeyshift(pkey)); + + write_iamr(old_iamr | new_iamr_bits); +} + +static void pkey_status_change(int pkey, bool enable) +{ + u64 old_uamor; + + /* Reset the AMR and IAMR bits for this key */ + init_amr(pkey, 0x0); + init_iamr(pkey, 0x0); + + /* Enable/disable key */ + old_uamor = read_uamor(); + if (enable) + old_uamor |= (0x3ul << pkeyshift(pkey)); + else + old_uamor &= ~(0x3ul << pkeyshift(pkey)); + write_uamor(old_uamor); +} + +void __arch_activate_pkey(int pkey) +{ + pkey_status_change(pkey, true); +} + +void __arch_deactivate_pkey(int pkey) +{ + pkey_status_change(pkey, false); +} -- cgit