From e0a8e0d90a9f0be66ba49f4f2380a63c22d4aaae Mon Sep 17 00:00:00 2001 From: LEROY Christophe Date: Wed, 22 Apr 2015 12:06:43 +0200 Subject: powerpc/8xx: Handle PAGE_USER via APG bits Use of APG for handling PAGE_USER. All pages PP exec bits are set to either 000 or 011, which means respectively RW for Supervisor and no access for User, or RO for Supervisor and no access for user. Then we use the APG to say whether accesses are according to Page rules or "all Supervisor" rules (Access to all) Therefore, we define 2 APG groups corresponding to _PAGE_USER. Mx_AP are initialised as follows: GP0 => No user => 01 (all accesses performed according to page definition) GP1 => User => 00 (all accesses performed as supervisor according to page definition) This removes the special 8xx handling in pte_update() Signed-off-by: Christophe Leroy Signed-off-by: Scott Wood --- arch/powerpc/kernel/head_8xx.S | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) (limited to 'arch/powerpc/kernel/head_8xx.S') diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index c640bbb042b5..c79184d86f58 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -351,12 +351,15 @@ InstructionTLBMiss: rlwimi r11, r10, 32 - ((PAGE_SHIFT - 2) << 1), (PAGE_SHIFT - 2) << 1, 29 lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ - /* Load the MI_TWC with the attributes for this "segment." */ - MTSPR_CPU6(SPRN_MI_TWC, r11, r3) /* Set segment attributes */ - rlwinm r11, r11,0,0,19 /* Extract page descriptor page address */ /* Extract level 2 index */ rlwinm r10, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 - lwzx r10, r10, r11 /* Get the pte */ + rlwimi r10, r11, 0, 0, 32 - PAGE_SHIFT - 1 /* Add level 2 base */ + lwz r10, 0(r10) /* Get the pte */ + + /* Insert the APG into the TWC from the Linux PTE. */ + rlwimi r11, r10, 0, 26, 26 + /* Load the MI_TWC with the attributes for this "segment." */ + MTSPR_CPU6(SPRN_MI_TWC, r11, r3) /* Set segment attributes */ #ifdef CONFIG_SWAP rlwinm r11, r10, 32-5, _PAGE_PRESENT @@ -365,12 +368,12 @@ InstructionTLBMiss: #endif li r11, RPN_PATTERN /* The Linux PTE won't go exactly into the MMU TLB. - * Software indicator bits 21 and 28 must be clear. + * Software indicator bits 20-23 and 28 must be clear. * Software indicator bits 24, 25, 26, and 27 must be * set. All other Linux PTE bits control the behavior * of the MMU. */ - rlwimi r10, r11, 0, 0x07f8 /* Set 24-27, clear 21-23,28 */ + rlwimi r10, r11, 0, 0x0ff8 /* Set 24-27, clear 20-23,28 */ MTSPR_CPU6(SPRN_MI_RPN, r10, r3) /* Update TLB entry */ /* Restore registers */ @@ -411,13 +414,13 @@ DataStoreTLBMiss: rlwimi r10, r11, 0, 0, 32 - PAGE_SHIFT - 1 /* Add level 2 base */ lwz r10, 0(r10) /* Get the pte */ - /* Insert the Guarded flag into the TWC from the Linux PTE. - * It is bit 27 of both the Linux PTE and the TWC (at least + /* Insert the Guarded flag and APG into the TWC from the Linux PTE. + * It is bit 26-27 of both the Linux PTE and the TWC (at least * I got that right :-). It will be better when we can put * this into the Linux pgd/pmd and load it in the operation * above. */ - rlwimi r11, r10, 0, 27, 27 + rlwimi r11, r10, 0, 26, 27 /* Insert the WriteThru flag into the TWC from the Linux PTE. * It is bit 25 in the Linux PTE and bit 30 in the TWC */ -- cgit v1.2.3