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-rw-r--r--arch/arm/mm/Kconfig21
-rw-r--r--arch/arm/mm/abort-ev6.S16
-rw-r--r--arch/arm/mm/mm-armv.c5
3 files changed, 40 insertions, 2 deletions
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 5b670c9ac5e..c4fc6be629d 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -409,3 +409,24 @@ config CPU_BPREDICT_DISABLE
depends on CPU_ARM1020
help
Say Y here to disable branch prediction. If unsure, say N.
+
+config TLS_REG_EMUL
+ bool
+ default y if (SMP || CPU_32v6) && (CPU_32v5 || CPU_32v4 || CPU_32v3)
+ help
+ We might be running on an ARMv6+ processor which should have the TLS
+ register but for some reason we can't use it, or maybe an SMP system
+ using a pre-ARMv6 processor (there are apparently a few prototypes
+ like that in existence) and therefore access to that register must
+ be emulated.
+
+config HAS_TLS_REG
+ bool
+ depends on CPU_32v6
+ default y if !TLS_REG_EMUL
+ help
+ This selects support for the CP15 thread register.
+ It is defined to be available on ARMv6 or later. If a particular
+ ARMv6 or later CPU doesn't support it then it must omc;ide "select
+ TLS_REG_EMUL" along with its other caracteristics.
+
diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S
index 38b2cbb89be..8f76f3df7b4 100644
--- a/arch/arm/mm/abort-ev6.S
+++ b/arch/arm/mm/abort-ev6.S
@@ -1,5 +1,6 @@
#include <linux/linkage.h>
#include <asm/assembler.h>
+#include "abort-macro.S"
/*
* Function: v6_early_abort
*
@@ -13,11 +14,26 @@
* : sp = pointer to registers
*
* Purpose : obtain information about current aborted instruction.
+ * Note: we read user space. This means we might cause a data
+ * abort here if the I-TLB and D-TLB aren't seeing the same
+ * picture. Unfortunately, this does happen. We live with it.
*/
.align 5
ENTRY(v6_early_abort)
mrc p15, 0, r1, c5, c0, 0 @ get FSR
mrc p15, 0, r0, c6, c0, 0 @ get FAR
+/*
+ * Faulty SWP instruction on 1136 doesn't set bit 11 in DFSR.
+ * The test below covers all the write situations, including Java bytecodes
+ */
+ bic r1, r1, #1 << 11 | 1 << 10 @ clear bits 11 and 10 of FSR
+ tst r3, #PSR_J_BIT @ Java?
+ movne pc, lr
+ do_thumb_abort
+ ldreq r3, [r2] @ read aborted ARM instruction
+ do_ldrd_abort
+ tst r3, #1 << 20 @ L = 0 -> write
+ orreq r1, r1, #1 << 11 @ yes.
mov pc, lr
diff --git a/arch/arm/mm/mm-armv.c b/arch/arm/mm/mm-armv.c
index f5a87db8b49..585dfb8e20b 100644
--- a/arch/arm/mm/mm-armv.c
+++ b/arch/arm/mm/mm-armv.c
@@ -411,9 +411,10 @@ static void __init build_mem_type_table(void)
mem_types[MT_MEMORY].prot_sect &= ~PMD_BIT4;
mem_types[MT_ROM].prot_sect &= ~PMD_BIT4;
/*
- * Mark cache clean areas read only from SVC mode
- * and no access from userspace.
+ * Mark cache clean areas and XIP ROM read only
+ * from SVC mode and no access from userspace.
*/
+ mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
}