lkml.org 
[lkml]   [2013]   [Sep]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH v2] powerpc 8xx: Fixing issue with CONFIG_PIN_TLB
This is a reorganisation of the setup of the TLB at kernel startup, in order
to handle the CONFIG_PIN_TLB case in accordance with chapter 8.10.3 of MPC866
and MPC885 reference manuals.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

diff -ur linux-3.11.org/arch/powerpc/kernel/head_8xx.S linux-3.11/arch/powerpc/kernel/head_8xx.S
--- linux-3.11.org/arch/powerpc/kernel/head_8xx.S 2013-09-02 22:46:10.000000000 +0200
+++ linux-3.11/arch/powerpc/kernel/head_8xx.S 2013-09-09 11:28:54.000000000 +0200
@@ -785,27 +785,24 @@
* these mappings is mapped by page tables.
*/
initial_mmu:
- tlbia /* Invalidate all TLB entries */
-/* Always pin the first 8 MB ITLB to prevent ITLB
- misses while mucking around with SRR0/SRR1 in asm
-*/
- lis r8, MI_RSV4I@h
- ori r8, r8, 0x1c00
-
+ lis r8, MI_RESETVAL@h
mtspr SPRN_MI_CTR, r8 /* Set instruction MMU control */

-#ifdef CONFIG_PIN_TLB
- lis r10, (MD_RSV4I | MD_RESETVAL)@h
- ori r10, r10, 0x1c00
- mr r8, r10
-#else
lis r10, MD_RESETVAL@h
-#endif
#ifndef CONFIG_8xx_COPYBACK
oris r10, r10, MD_WTDEF@h
#endif
mtspr SPRN_MD_CTR, r10 /* Set data TLB control */

+ tlbia /* Invalidate all TLB entries */
+
+ ori r8, r8, 0x1c00
+ mtspr SPRN_MI_CTR, r8 /* Set instruction MMU control */
+#ifdef CONFIG_PIN_TLB
+ ori r10, r10, 0x1c00
+ mtspr SPRN_MD_CTR, r10 /* Set data TLB control */
+#endif
+
/* Now map the lower 8 Meg into the TLBs. For this quick hack,
* we can load the instruction and data TLB registers with the
* same values.
@@ -825,6 +822,12 @@
mtspr SPRN_MI_AP, r8
mtspr SPRN_MD_AP, r8

+ /* Always pin the first 8 MB ITLB to prevent ITLB
+ * misses while mucking around with SRR0/SRR1 in asm
+ */
+ lis r8, (MI_RSV4I | MI_RESETVAL)@h
+ mtspr SPRN_MI_CTR, r8 /* Set instruction MMU control */
+
/* Map another 8 MByte at the IMMR to get the processor
* internal registers (among other things).
*/
@@ -870,7 +873,15 @@
mtspr SPRN_MD_TWC, r9
addis r11, r11, 0x0080 /* Add 8M */
mtspr SPRN_MD_RPN, r11
+
+ lis r10, (MD_RSV4I | MD_RESETVAL)@h
+#else
+ lis r10, MD_RESETVAL@h
#endif
+#ifndef CONFIG_8xx_COPYBACK
+ oris r10, r10, MD_WTDEF@h
+#endif
+ mtspr SPRN_MD_CTR, r10 /* Set data TLB control */

/* Since the cache is enabled according to the information we
* just loaded into the TLB, invalidate and enable the caches here.

\
 
 \ /
  Last update: 2013-09-13 05:21    [W:0.105 / U:1.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site