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-rw-r--r--arch/arm/mm/alignment.c26
-rw-r--r--arch/arm/mm/cache-feroceon-l2.c4
-rw-r--r--arch/arm/mm/fault.c1
-rw-r--r--arch/arm/mm/mmu.c6
4 files changed, 32 insertions, 5 deletions
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index 133e65d166b..2d5884ce043 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -70,6 +70,10 @@ static unsigned long ai_dword;
static unsigned long ai_multi;
static int ai_usermode;
+#define UM_WARN (1 << 0)
+#define UM_FIXUP (1 << 1)
+#define UM_SIGNAL (1 << 2)
+
#ifdef CONFIG_PROC_FS
static const char *usermode_action[] = {
"ignored",
@@ -754,7 +758,7 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
user:
ai_user += 1;
- if (ai_usermode & 1)
+ if (ai_usermode & UM_WARN)
printk("Alignment trap: %s (%d) PC=0x%08lx Instr=0x%0*lx "
"Address=0x%08lx FSR 0x%03x\n", current->comm,
task_pid_nr(current), instrptr,
@@ -762,10 +766,10 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
thumb_mode(regs) ? tinstr : instr,
addr, fsr);
- if (ai_usermode & 2)
+ if (ai_usermode & UM_FIXUP)
goto fixup;
- if (ai_usermode & 4)
+ if (ai_usermode & UM_SIGNAL)
force_sig(SIGBUS, current);
else
set_cr(cr_no_alignment);
@@ -796,6 +800,22 @@ static int __init alignment_init(void)
res->write_proc = proc_alignment_write;
#endif
+ /*
+ * ARMv6 and later CPUs can perform unaligned accesses for
+ * most single load and store instructions up to word size.
+ * LDM, STM, LDRD and STRD still need to be handled.
+ *
+ * Ignoring the alignment fault is not an option on these
+ * CPUs since we spin re-faulting the instruction without
+ * making any progress.
+ */
+ if (cpu_architecture() >= CPU_ARCH_ARMv6 && (cr_alignment & CR_U)) {
+ cr_alignment &= ~CR_A;
+ cr_no_alignment &= ~CR_A;
+ set_cr(cr_alignment);
+ ai_usermode = UM_FIXUP;
+ }
+
hook_fault_code(1, do_alignment, SIGILL, "alignment exception");
hook_fault_code(3, do_alignment, SIGILL, "alignment exception");
diff --git a/arch/arm/mm/cache-feroceon-l2.c b/arch/arm/mm/cache-feroceon-l2.c
index 13cdae8b0d4..80cd207cbae 100644
--- a/arch/arm/mm/cache-feroceon-l2.c
+++ b/arch/arm/mm/cache-feroceon-l2.c
@@ -150,7 +150,7 @@ static void feroceon_l2_inv_range(unsigned long start, unsigned long end)
/*
* Clean and invalidate partial last cache line.
*/
- if (end & (CACHE_LINE_SIZE - 1)) {
+ if (start < end && end & (CACHE_LINE_SIZE - 1)) {
l2_clean_inv_pa(end & ~(CACHE_LINE_SIZE - 1));
end &= ~(CACHE_LINE_SIZE - 1);
}
@@ -158,7 +158,7 @@ static void feroceon_l2_inv_range(unsigned long start, unsigned long end)
/*
* Invalidate all full cache lines between 'start' and 'end'.
*/
- while (start != end) {
+ while (start < end) {
unsigned long range_end = calc_range_end(start, end);
l2_inv_pa_range(start, range_end - CACHE_LINE_SIZE);
start = range_end;
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 2df8d9facf5..22c9530e91e 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -11,6 +11,7 @@
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/mm.h>
+#include <linux/hardirq.h>
#include <linux/init.h>
#include <linux/kprobes.h>
#include <linux/uaccess.h>
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index e63db11f16a..7f36c825718 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -208,6 +208,12 @@ static struct mem_type mem_types[] = {
.prot_sect = PROT_SECT_DEVICE,
.domain = DOMAIN_IO,
},
+ [MT_UNCACHED] = {
+ .prot_pte = PROT_PTE_DEVICE,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
+ .domain = DOMAIN_IO,
+ },
[MT_CACHECLEAN] = {
.prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
.domain = DOMAIN_KERNEL,