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-rw-r--r--arch/mips/Kconfig11
-rw-r--r--arch/mips/kernel/cpu-probe.c26
-rw-r--r--arch/mips/kernel/process.c14
3 files changed, 50 insertions, 1 deletions
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 5c863bcd561..1e3aeccd732 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1190,8 +1190,19 @@ config SYS_HAS_CPU_RM9000
config SYS_HAS_CPU_SB1
bool
+#
+# CPU may reorder R->R, R->W, W->R, W->W
+# Reordering beyond LL and SC is handled in WEAK_REORDERING_BEYOND_LLSC
+#
config WEAK_ORDERING
bool
+
+#
+# CPU may reorder reads and writes beyond LL/SC
+# CPU may reorder R->LL, R->LL, W->LL, W->LL, R->SC, R->SC, W->SC, W->SC
+#
+config WEAK_REORDERING_BEYOND_LLSC
+ bool
endmenu
#
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index c6b8b074a81..06448a9656d 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -75,6 +75,27 @@ static void r4k_wait_irqoff(void)
local_irq_enable();
}
+/*
+ * The RM7000 variant has to handle erratum 38. The workaround is to not
+ * have any pending stores when the WAIT instruction is executed.
+ */
+static void rm7k_wait_irqoff(void)
+{
+ local_irq_disable();
+ if (!need_resched())
+ __asm__(
+ " .set push \n"
+ " .set mips3 \n"
+ " .set noat \n"
+ " mfc0 $1, $12 \n"
+ " sync \n"
+ " mtc0 $1, $12 # stalls until W stage \n"
+ " wait \n"
+ " mtc0 $1, $12 # stalls until W stage \n"
+ " .set pop \n");
+ local_irq_enable();
+}
+
/* The Au1xxx wait is available only if using 32khz counter or
* external timer source, but specifically not CP0 Counter. */
int allow_au1k_wait;
@@ -132,7 +153,6 @@ static inline void check_wait(void)
case CPU_R4700:
case CPU_R5000:
case CPU_NEVADA:
- case CPU_RM7000:
case CPU_4KC:
case CPU_4KEC:
case CPU_4KSC:
@@ -142,6 +162,10 @@ static inline void check_wait(void)
cpu_wait = r4k_wait;
break;
+ case CPU_RM7000:
+ cpu_wait = rm7k_wait_irqoff;
+ break;
+
case CPU_24K:
case CPU_34K:
cpu_wait = r4k_wait;
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 8f4cf27c715..bd05f5a927e 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -25,7 +25,9 @@
#include <linux/init.h>
#include <linux/completion.h>
#include <linux/kallsyms.h>
+#include <linux/random.h>
+#include <asm/asm.h>
#include <asm/bootinfo.h>
#include <asm/cpu.h>
#include <asm/dsp.h>
@@ -460,3 +462,15 @@ unsigned long get_wchan(struct task_struct *task)
out:
return pc;
}
+
+/*
+ * Don't forget that the stack pointer must be aligned on a 8 bytes
+ * boundary for 32-bits ABI and 16 bytes for 64-bits ABI.
+ */
+unsigned long arch_align_stack(unsigned long sp)
+{
+ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
+ sp -= get_random_int() & ~PAGE_MASK;
+
+ return sp & ALMASK;
+}