[PATCH v5 10/22] powerpc/8xx: regroup TLB handler routines

From: Christophe Leroy
Date: Tue Sep 25 2018 - 12:51:03 EST


As this is running with MMU off, the CPU only does speculative
fetch for code in the same page.

Following the significant size reduction of TLB handler routines,
the side handlers can be brought back close to the main part,
ie in the same page.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/kernel/head_8xx.S | 112 ++++++++++++++++++++---------------------
1 file changed, 54 insertions(+), 58 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index d69c6e3d5cc1..3e38af7489a9 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -400,6 +400,23 @@ InstructionTLBMiss:
rfi
#endif

+#ifndef CONFIG_PIN_TLB_TEXT
+ITLBMissLinear:
+ mtcr r11
+ /* Set 8M byte page and mark it valid */
+ li r11, MI_PS8MEG | MI_SVALID
+ mtspr SPRN_MI_TWC, r11
+ rlwinm r10, r10, 20, 0x0f800000 /* 8xx supports max 256Mb RAM */
+ ori r10, r10, 0xf0 | MI_SPS16K | _PAGE_SH | _PAGE_DIRTY | \
+ _PAGE_PRESENT
+ mtspr SPRN_MI_RPN, r10 /* Update TLB entry */
+
+0: mfspr r10, SPRN_SPRG_SCRATCH0
+ mfspr r11, SPRN_SPRG_SCRATCH1
+ rfi
+ patch_site 0b, patch__itlbmiss_exit_2
+#endif
+
. = 0x1200
DataStoreTLBMiss:
mtspr SPRN_SPRG_SCRATCH0, r10
@@ -485,6 +502,43 @@ DataStoreTLBMiss:
rfi
#endif

+DTLBMissIMMR:
+ mtcr r11
+ /* Set 512k byte guarded page and mark it valid */
+ li r10, MD_PS512K | MD_GUARDED | MD_SVALID
+ mtspr SPRN_MD_TWC, r10
+ mfspr r10, SPRN_IMMR /* Get current IMMR */
+ rlwinm r10, r10, 0, 0xfff80000 /* Get 512 kbytes boundary */
+ ori r10, r10, 0xf0 | MD_SPS16K | _PAGE_SH | _PAGE_DIRTY | \
+ _PAGE_PRESENT | _PAGE_NO_CACHE
+ mtspr SPRN_MD_RPN, r10 /* Update TLB entry */
+
+ li r11, RPN_PATTERN
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+
+0: mfspr r10, SPRN_SPRG_SCRATCH0
+ mfspr r11, SPRN_SPRG_SCRATCH1
+ rfi
+ patch_site 0b, patch__dtlbmiss_exit_2
+
+DTLBMissLinear:
+ mtcr r11
+ /* Set 8M byte page and mark it valid */
+ li r11, MD_PS8MEG | MD_SVALID
+ mtspr SPRN_MD_TWC, r11
+ rlwinm r10, r10, 20, 0x0f800000 /* 8xx supports max 256Mb RAM */
+ ori r10, r10, 0xf0 | MD_SPS16K | _PAGE_SH | _PAGE_DIRTY | \
+ _PAGE_PRESENT
+ mtspr SPRN_MD_RPN, r10 /* Update TLB entry */
+
+ li r11, RPN_PATTERN
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+
+0: mfspr r10, SPRN_SPRG_SCRATCH0
+ mfspr r11, SPRN_SPRG_SCRATCH1
+ rfi
+ patch_site 0b, patch__dtlbmiss_exit_3
+
/* This is an instruction TLB error on the MPC8xx. This could be due
* to many reasons, such as executing guarded memory or illegal instruction
* addresses. There is nothing to do but handle a big time error fault.
@@ -584,64 +638,6 @@ InstructionBreakpoint:

. = 0x2000

-/*
- * Bottom part of DataStoreTLBMiss handlers for IMMR area and linear RAM.
- * not enough space in the DataStoreTLBMiss area.
- */
-DTLBMissIMMR:
- mtcr r11
- /* Set 512k byte guarded page and mark it valid */
- li r10, MD_PS512K | MD_GUARDED | MD_SVALID
- mtspr SPRN_MD_TWC, r10
- mfspr r10, SPRN_IMMR /* Get current IMMR */
- rlwinm r10, r10, 0, 0xfff80000 /* Get 512 kbytes boundary */
- ori r10, r10, 0xf0 | MD_SPS16K | _PAGE_SH | _PAGE_DIRTY | \
- _PAGE_PRESENT | _PAGE_NO_CACHE
- mtspr SPRN_MD_RPN, r10 /* Update TLB entry */
-
- li r11, RPN_PATTERN
- mtspr SPRN_DAR, r11 /* Tag DAR */
-
-0: mfspr r10, SPRN_SPRG_SCRATCH0
- mfspr r11, SPRN_SPRG_SCRATCH1
- rfi
- patch_site 0b, patch__dtlbmiss_exit_2
-
-DTLBMissLinear:
- mtcr r11
- /* Set 8M byte page and mark it valid */
- li r11, MD_PS8MEG | MD_SVALID
- mtspr SPRN_MD_TWC, r11
- rlwinm r10, r10, 20, 0x0f800000 /* 8xx supports max 256Mb RAM */
- ori r10, r10, 0xf0 | MD_SPS16K | _PAGE_SH | _PAGE_DIRTY | \
- _PAGE_PRESENT
- mtspr SPRN_MD_RPN, r10 /* Update TLB entry */
-
- li r11, RPN_PATTERN
- mtspr SPRN_DAR, r11 /* Tag DAR */
-
-0: mfspr r10, SPRN_SPRG_SCRATCH0
- mfspr r11, SPRN_SPRG_SCRATCH1
- rfi
- patch_site 0b, patch__dtlbmiss_exit_3
-
-#ifndef CONFIG_PIN_TLB_TEXT
-ITLBMissLinear:
- mtcr r11
- /* Set 8M byte page and mark it valid */
- li r11, MI_PS8MEG | MI_SVALID
- mtspr SPRN_MI_TWC, r11
- rlwinm r10, r10, 20, 0x0f800000 /* 8xx supports max 256Mb RAM */
- ori r10, r10, 0xf0 | MI_SPS16K | _PAGE_SH | _PAGE_DIRTY | \
- _PAGE_PRESENT
- mtspr SPRN_MI_RPN, r10 /* Update TLB entry */
-
-0: mfspr r10, SPRN_SPRG_SCRATCH0
- mfspr r11, SPRN_SPRG_SCRATCH1
- rfi
- patch_site 0b, patch__itlbmiss_exit_2
-#endif
-
/* This is the procedure to calculate the data EA for buggy dcbx,dcbi instructions
* by decoding the registers used by the dcbx instruction and adding them.
* DAR is set to the calculated address.
--
2.13.3