Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4d70b698 authored by Ram Pai's avatar Ram Pai Committed by Michael Ellerman
Browse files

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: default avatarThiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: default avatarRam Pai <linuxram@us.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 1b4037de

arch/powerpc/mm/pkeys.c

+47 −0
Original line number Diff line number Diff line
@@ -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);

}