E200 have TLB1 only and it does not have TLB0.
So TLB1 are used for mapping kernel and user-space both.
TLB miss handler for E200 does not consider skipping TLBs
used for kernel mapping. This patch ensures that we skip
tlb1 entries used for kernel mapping (tlbcam_index).

Signed-off-by: Bharat Bhushan <bharat.bhus...@nxp.com>
---
 arch/powerpc/kernel/head_fsl_booke.S | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/head_fsl_booke.S 
b/arch/powerpc/kernel/head_fsl_booke.S
index bf4c602..951fb96 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -801,12 +801,28 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS)
        /* Round robin TLB1 entries assignment */
        mfspr   r12, SPRN_MAS0
 
+       /* Get first free tlbcam entry */
+       lis     r11, tlbcam_index@ha
+       lwz     r11, tlbcam_index@l(r11)
+
+       /* Extract MAS0(NV) */
+       andi.   r13, r12, 0xfff
+       cmpw    0, r13, r11
+       blt     0, 5f
+       b       6f
+5:
+       /* When NV is less than first free tlbcam entry, use first free
+        * tlbcam entry for ESEL and set NV */
+       rlwimi  r12, r11, 16, 4, 15
+       addi    r11, r11, 1
+       rlwimi  r12, r11, 0, 20, 31
+       b       7f
+6:
        /* Extract TLB1CFG(NENTRY) */
        mfspr   r11, SPRN_TLB1CFG
        andi.   r11, r11, 0xfff
 
-       /* Extract MAS0(NV) */
-       andi.   r13, r12, 0xfff
+       /* Set MAS0(NV) for next TLB miss exception */
        addi    r13, r13, 1
        cmpw    0, r13, r11
        addi    r12, r12, 1
-- 
1.9.3

Reply via email to