[PATCH] MIPS: Optimize TLB refill for RI/XI configurations.

[PATCH] MIPS: Optimize TLB refill for RI/XI configurations.

[David Daney]

From: David Daney <ddaney@caviumnetworks.com>

We don't have to do a separate shift to eliminate the software bits,
just rotate them into the fill and they will be ignored.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
---
 arch/mips/mm/tlbex.c | 23 +++++++----------------
 1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 03eb0ef..4f33acd 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -587,8 +587,7 @@ static __cpuinit __maybe_unused void build_convert_pte_to_entrylo(u32 **p,
 								  unsigned int reg)
 {
 	if (kernel_uses_smartmips_rixi) {
-		UASM_i_SRL(p, reg, reg, ilog2(_PAGE_NO_EXEC));
-		UASM_i_ROTR(p, reg, reg, ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+		UASM_i_ROTR(p, reg, reg, ilog2(_PAGE_GLOBAL));
 	} else {
 #ifdef CONFIG_64BIT_PHYS_ADDR
 		uasm_i_dsrl_safe(p, reg, reg, ilog2(_PAGE_GLOBAL));
@@ -991,11 +990,9 @@ static void __cpuinit build_update_entries(u32 **p, unsigned int tmp,
 		uasm_i_ld(p, tmp, 0, ptep); /* get even pte */
 		uasm_i_ld(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
 		if (kernel_uses_smartmips_rixi) {
-			UASM_i_SRL(p, tmp, tmp, ilog2(_PAGE_NO_EXEC));
-			UASM_i_SRL(p, ptep, ptep, ilog2(_PAGE_NO_EXEC));
-			UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+			UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
 			UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
-			UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+			UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL));
 		} else {
 			uasm_i_dsrl_safe(p, tmp, tmp, ilog2(_PAGE_GLOBAL)); /* convert to entrylo0 */
 			UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
@@ -1018,13 +1015,11 @@ static void __cpuinit build_update_entries(u32 **p, unsigned int tmp,
 	if (r45k_bvahwbug())
 		build_tlb_probe_entry(p);
 	if (kernel_uses_smartmips_rixi) {
-		UASM_i_SRL(p, tmp, tmp, ilog2(_PAGE_NO_EXEC));
-		UASM_i_SRL(p, ptep, ptep, ilog2(_PAGE_NO_EXEC));
-		UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+		UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
 		if (r4k_250MHZhwbug())
 			UASM_i_MTC0(p, 0, C0_ENTRYLO0);
 		UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
-		UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+		UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL));
 	} else {
 		UASM_i_SRL(p, tmp, tmp, ilog2(_PAGE_GLOBAL)); /* convert to entrylo0 */
 		if (r4k_250MHZhwbug())
@@ -1184,13 +1179,9 @@ build_fast_tlb_refill_handler (u32 **p, struct uasm_label **l,
 		UASM_i_LW(p, odd, sizeof(pte_t), ptr); /* get odd pte */
 	}
 	if (kernel_uses_smartmips_rixi) {
-		uasm_i_dsrl_safe(p, even, even, ilog2(_PAGE_NO_EXEC));
-		uasm_i_dsrl_safe(p, odd, odd, ilog2(_PAGE_NO_EXEC));
-		uasm_i_drotr(p, even, even,
-			     ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+		uasm_i_drotr(p, even, even, ilog2(_PAGE_GLOBAL));
 		UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
-		uasm_i_drotr(p, odd, odd,
-			     ilog2(_PAGE_GLOBAL) - ilog2(_PAGE_NO_EXEC));
+		uasm_i_drotr(p, odd, odd, ilog2(_PAGE_GLOBAL));
 	} else {
 		uasm_i_dsrl_safe(p, even, even, ilog2(_PAGE_GLOBAL));
 		UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
-- 
1.7.11.4

Re: [PATCH] MIPS: Optimize TLB refill for RI/XI configurations.

[Ralf Baechle]

Thanks, queued.

  Ralf