Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  [MIPS] User stack pointer randomisation
  [MIPS] Remove unused include/asm-mips/gfx.h
  [MIPS] Remove unused include/asm-mips/ds1216.h
  [MIPS] Workaround for RM7000 WAIT instruction aka erratum 38
  [MIPS] Make support for weakly ordered LL/SC a config option.
  [MIPS] Disable UserLocal runtime detection on platforms which never have it.
  [MIPS] Disable MT runtime detection on platforms which never support MT.

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;
+}