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

Pull MIPS updates from Ralf Baechle:
 "Boston platform support:
   - Document DT bindings
   - Add CLK driver for board clocks

  CM:
   - Avoid per-core locking with CM3 & higher
   - WARN on attempt to lock invalid VP, not BUG

  CPS:
   - Select CONFIG_SYS_SUPPORTS_SCHED_SMT for MIPSr6
   - Prevent multi-core with dcache aliasing
   - Handle cores not powering down more gracefully
   - Handle spurious VP starts more gracefully

  DSP:
   - Add lwx & lhx missaligned access support

  eBPF:
   - Add MIPS support along with many supporting change to add the
     required infrastructure

  Generic arch code:
   - Misc sysmips MIPS_ATOMIC_SET fixes
   - Drop duplicate HAVE_SYSCALL_TRACEPOINTS
   - Negate error syscall return in trace
   - Correct forced syscall errors
   - Traced negative syscalls should return -ENOSYS
   - Allow samples/bpf/tracex5 to access syscall arguments for sane
     traces
   - Cleanup from old Kconfig options in defconfigs
   - Fix PREF instruction usage by memcpy for MIPS R6
   - Fix various special cases in the FPU eulation
   - Fix some special cases in MIPS16e2 support
   - Fix MIPS I ISA /proc/cpuinfo reporting
   - Sort MIPS Kconfig alphabetically
   - Fix minimum alignment requirement of IRQ stack as required by
     ABI / GCC
   - Fix special cases in the module loader
   - Perform post-DMA cache flushes on systems with MAARs
   - Probe the I6500 CPU
   - Cleanup cmpxchg and add support for 1 and 2 byte operations
   - Use queued read/write locks (qrwlock)
   - Use queued spinlocks (qspinlock)
   - Add CPU shared FTLB feature detection
   - Handle tlbex-tlbp race condition
   - Allow storing pgd in C0_CONTEXT for MIPSr6
   - Use current_cpu_type() in m4kc_tlbp_war()
   - Support Boston in the generic kernel

  Generic platform:
   - yamon-dt: Pull YAMON DT shim code out of SEAD-3 board
   - yamon-dt: Support > 256MB of RAM
   - yamon-dt: Use serial* rather than uart* aliases
   - Abstract FDT fixup application
   - Set RTC_ALWAYS_BCD to 0
   - Add a MAINTAINERS entry

  core kernel:
   - qspinlock.c: include linux/prefetch.h

  Loongson 3:
   - Add support

  Perf:
   - Add I6500 support

  SEAD-3:
   - Remove GIC timer from DT
   - Set interrupt-parent per-device, not at root node
   - Fix GIC interrupt specifiers

  SMP:
   - Skip IPI setup if we only have a single CPU

  VDSO:
   - Make comment match reality
   - Improvements to time code in VDSO"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (86 commits)
  locking/qspinlock: Include linux/prefetch.h
  MIPS: Fix MIPS I ISA /proc/cpuinfo reporting
  MIPS: Fix minimum alignment requirement of IRQ stack
  MIPS: generic: Support MIPS Boston development boards
  MIPS: DTS: img: Don't attempt to build-in all .dtb files
  clk: boston: Add a driver for MIPS Boston board clocks
  dt-bindings: Document img,boston-clock binding
  MIPS: Traced negative syscalls should return -ENOSYS
  MIPS: Correct forced syscall errors
  MIPS: Negate error syscall return in trace
  MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select
  MIPS16e2: Provide feature overrides for non-MIPS16 systems
  MIPS: MIPS16e2: Report ASE presence in /proc/cpuinfo
  MIPS: MIPS16e2: Subdecode extended LWSP/SWSP instructions
  MIPS: MIPS16e2: Identify ASE presence
  MIPS: VDSO: Fix a mismatch between comment and preprocessor constant
  MIPS: VDSO: Add implementation of gettimeofday() fallback
  MIPS: VDSO: Add implementation of clock_gettime() fallback
  MIPS: VDSO: Fix conversions in do_monotonic()/do_monotonic_coarse()
  MIPS: Use current_cpu_type() in m4kc_tlbp_war()
  ...

1 files changed, 121 insertions, 159 deletions

diff --git a/arch/mips/include/asm/cmpxchg.h b/arch/mips/include/asm/cmpxchg.h
index b71ab4a5fd50..903f3bf48419 100644
--- a/arch/mips/include/asm/cmpxchg.h
+++ b/arch/mips/include/asm/cmpxchg.h
@@ -13,153 +13,107 @@
 #include <asm/compiler.h>
 #include <asm/war.h>
 
-static inline unsigned long __xchg_u32(volatile int * m, unsigned int val)
-{
-	__u32 retval;
-
-	smp_mb__before_llsc();
-
-	if (kernel_uses_llsc && R10000_LLSC_WAR) {
-		unsigned long dummy;
-
-		__asm__ __volatile__(
-		"	.set	arch=r4000				\n"
-		"1:	ll	%0, %3			# xchg_u32	\n"
-		"	.set	mips0					\n"
-		"	move	%2, %z4					\n"
-		"	.set	arch=r4000				\n"
-		"	sc	%2, %1					\n"
-		"	beqzl	%2, 1b					\n"
-		"	.set	mips0					\n"
-		: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m), "=&r" (dummy)
-		: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
-		: "memory");
-	} else if (kernel_uses_llsc) {
-		unsigned long dummy;
-
-		do {
-			__asm__ __volatile__(
-			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-			"	ll	%0, %3		# xchg_u32	\n"
-			"	.set	mips0				\n"
-			"	move	%2, %z4				\n"
-			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-			"	sc	%2, %1				\n"
-			"	.set	mips0				\n"
-			: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m),
-			  "=&r" (dummy)
-			: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
-			: "memory");
-		} while (unlikely(!dummy));
-	} else {
-		unsigned long flags;
-
-		raw_local_irq_save(flags);
-		retval = *m;
-		*m = val;
-		raw_local_irq_restore(flags);	/* implies memory barrier  */
-	}
-
-	smp_llsc_mb();
-
-	return retval;
-}
+/*
+ * Using a branch-likely instruction to check the result of an sc instruction
+ * works around a bug present in R10000 CPUs prior to revision 3.0 that could
+ * cause ll-sc sequences to execute non-atomically.
+ */
+#if R10000_LLSC_WAR
+# define __scbeqz "beqzl"
+#else
+# define __scbeqz "beqz"
+#endif
 
-#ifdef CONFIG_64BIT
-static inline __u64 __xchg_u64(volatile __u64 * m, __u64 val)
-{
-	__u64 retval;
-
-	smp_mb__before_llsc();
-
-	if (kernel_uses_llsc && R10000_LLSC_WAR) {
-		unsigned long dummy;
-
-		__asm__ __volatile__(
-		"	.set	arch=r4000				\n"
-		"1:	lld	%0, %3			# xchg_u64	\n"
-		"	move	%2, %z4					\n"
-		"	scd	%2, %1					\n"
-		"	beqzl	%2, 1b					\n"
-		"	.set	mips0					\n"
-		: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m), "=&r" (dummy)
-		: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
-		: "memory");
-	} else if (kernel_uses_llsc) {
-		unsigned long dummy;
-
-		do {
-			__asm__ __volatile__(
-			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-			"	lld	%0, %3		# xchg_u64	\n"
-			"	move	%2, %z4				\n"
-			"	scd	%2, %1				\n"
-			"	.set	mips0				\n"
-			: "=&r" (retval), "=" GCC_OFF_SMALL_ASM() (*m),
-			  "=&r" (dummy)
-			: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)
-			: "memory");
-		} while (unlikely(!dummy));
-	} else {
-		unsigned long flags;
-
-		raw_local_irq_save(flags);
-		retval = *m;
-		*m = val;
-		raw_local_irq_restore(flags);	/* implies memory barrier  */
-	}
+/*
+ * These functions doesn't exist, so if they are called you'll either:
+ *
+ * - Get an error at compile-time due to __compiletime_error, if supported by
+ *   your compiler.
+ *
+ * or:
+ *
+ * - Get an error at link-time due to the call to the missing function.
+ */
+extern unsigned long __cmpxchg_called_with_bad_pointer(void)
+	__compiletime_error("Bad argument size for cmpxchg");
+extern unsigned long __xchg_called_with_bad_pointer(void)
+	__compiletime_error("Bad argument size for xchg");
 
-	smp_llsc_mb();
+#define __xchg_asm(ld, st, m, val)					\
+({									\
+	__typeof(*(m)) __ret;						\
+									\
+	if (kernel_uses_llsc) {						\
+		__asm__ __volatile__(					\
+		"	.set	push				\n"	\
+		"	.set	noat				\n"	\
+		"	.set	" MIPS_ISA_ARCH_LEVEL "		\n"	\
+		"1:	" ld "	%0, %2		# __xchg_asm	\n"	\
+		"	.set	mips0				\n"	\
+		"	move	$1, %z3				\n"	\
+		"	.set	" MIPS_ISA_ARCH_LEVEL "		\n"	\
+		"	" st "	$1, %1				\n"	\
+		"\t" __scbeqz "	$1, 1b				\n"	\
+		"	.set	pop				\n"	\
+		: "=&r" (__ret), "=" GCC_OFF_SMALL_ASM() (*m)		\
+		: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)			\
+		: "memory");						\
+	} else {							\
+		unsigned long __flags;					\
+									\
+		raw_local_irq_save(__flags);				\
+		__ret = *m;						\
+		*m = val;						\
+		raw_local_irq_restore(__flags);				\
+	}								\
+									\
+	__ret;								\
+})
 
-	return retval;
-}
-#else
-extern __u64 __xchg_u64_unsupported_on_32bit_kernels(volatile __u64 * m, __u64 val);
-#define __xchg_u64 __xchg_u64_unsupported_on_32bit_kernels
-#endif
+extern unsigned long __xchg_small(volatile void *ptr, unsigned long val,
+				  unsigned int size);
 
-static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
+static inline unsigned long __xchg(volatile void *ptr, unsigned long x,
+				   int size)
 {
 	switch (size) {
+	case 1:
+	case 2:
+		return __xchg_small(ptr, x, size);
+
 	case 4:
-		return __xchg_u32(ptr, x);
+		return __xchg_asm("ll", "sc", (volatile u32 *)ptr, x);
+
 	case 8:
-		return __xchg_u64(ptr, x);
-	}
+		if (!IS_ENABLED(CONFIG_64BIT))
+			return __xchg_called_with_bad_pointer();
+
+		return __xchg_asm("lld", "scd", (volatile u64 *)ptr, x);
 
-	return x;
+	default:
+		return __xchg_called_with_bad_pointer();
+	}
 }
 
 #define xchg(ptr, x)							\
 ({									\
-	BUILD_BUG_ON(sizeof(*(ptr)) & ~0xc);				\
+	__typeof__(*(ptr)) __res;					\
 									\
-	((__typeof__(*(ptr)))						\
-		__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))));	\
+	smp_mb__before_llsc();						\
+									\
+	__res = (__typeof__(*(ptr)))					\
+		__xchg((ptr), (unsigned long)(x), sizeof(*(ptr)));	\
+									\
+	smp_llsc_mb();							\
+									\
+	__res;								\
 })
 
 #define __cmpxchg_asm(ld, st, m, old, new)				\
 ({									\
 	__typeof(*(m)) __ret;						\
 									\
-	if (kernel_uses_llsc && R10000_LLSC_WAR) {			\
-		__asm__ __volatile__(					\
-		"	.set	push				\n"	\
-		"	.set	noat				\n"	\
-		"	.set	arch=r4000			\n"	\
-		"1:	" ld "	%0, %2		# __cmpxchg_asm \n"	\
-		"	bne	%0, %z3, 2f			\n"	\
-		"	.set	mips0				\n"	\
-		"	move	$1, %z4				\n"	\
-		"	.set	arch=r4000			\n"	\
-		"	" st "	$1, %1				\n"	\
-		"	beqzl	$1, 1b				\n"	\
-		"2:						\n"	\
-		"	.set	pop				\n"	\
-		: "=&r" (__ret), "=" GCC_OFF_SMALL_ASM() (*m)		\
-		: GCC_OFF_SMALL_ASM() (*m), "Jr" (old), "Jr" (new)		\
-		: "memory");						\
-	} else if (kernel_uses_llsc) {					\
+	if (kernel_uses_llsc) {						\
 		__asm__ __volatile__(					\
 		"	.set	push				\n"	\
 		"	.set	noat				\n"	\
@@ -170,7 +124,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz
 		"	move	$1, %z4				\n"	\
 		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
 		"	" st "	$1, %1				\n"	\
-		"	beqz	$1, 1b				\n"	\
+		"\t" __scbeqz "	$1, 1b				\n"	\
 		"	.set	pop				\n"	\
 		"2:						\n"	\
 		: "=&r" (__ret), "=" GCC_OFF_SMALL_ASM() (*m)		\
@@ -189,44 +143,50 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz
 	__ret;								\
 })
 
-/*
- * This function doesn't exist, so you'll get a linker error
- * if something tries to do an invalid cmpxchg().
- */
-extern void __cmpxchg_called_with_bad_pointer(void);
+extern unsigned long __cmpxchg_small(volatile void *ptr, unsigned long old,
+				     unsigned long new, unsigned int size);
+
+static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
+				      unsigned long new, unsigned int size)
+{
+	switch (size) {
+	case 1:
+	case 2:
+		return __cmpxchg_small(ptr, old, new, size);
+
+	case 4:
+		return __cmpxchg_asm("ll", "sc", (volatile u32 *)ptr, old, new);
+
+	case 8:
+		/* lld/scd are only available for MIPS64 */
+		if (!IS_ENABLED(CONFIG_64BIT))
+			return __cmpxchg_called_with_bad_pointer();
+
+		return __cmpxchg_asm("lld", "scd", (volatile u64 *)ptr, old, new);
 
-#define __cmpxchg(ptr, old, new, pre_barrier, post_barrier)		\
+	default:
+		return __cmpxchg_called_with_bad_pointer();
+	}
+}
+
+#define cmpxchg_local(ptr, old, new)					\
+	((__typeof__(*(ptr)))						\
+		__cmpxchg((ptr),					\
+			  (unsigned long)(__typeof__(*(ptr)))(old),	\
+			  (unsigned long)(__typeof__(*(ptr)))(new),	\
+			  sizeof(*(ptr))))
+
+#define cmpxchg(ptr, old, new)						\
 ({									\
-	__typeof__(ptr) __ptr = (ptr);					\
-	__typeof__(*(ptr)) __old = (old);				\
-	__typeof__(*(ptr)) __new = (new);				\
-	__typeof__(*(ptr)) __res = 0;					\
+	__typeof__(*(ptr)) __res;					\
 									\
-	pre_barrier;							\
-									\
-	switch (sizeof(*(__ptr))) {					\
-	case 4:								\
-		__res = __cmpxchg_asm("ll", "sc", __ptr, __old, __new); \
-		break;							\
-	case 8:								\
-		if (sizeof(long) == 8) {				\
-			__res = __cmpxchg_asm("lld", "scd", __ptr,	\
-					   __old, __new);		\
-			break;						\
-		}							\
-	default:							\
-		__cmpxchg_called_with_bad_pointer();			\
-		break;							\
-	}								\
-									\
-	post_barrier;							\
+	smp_mb__before_llsc();						\
+	__res = cmpxchg_local((ptr), (old), (new));			\
+	smp_llsc_mb();							\
 									\
 	__res;								\
 })
 
-#define cmpxchg(ptr, old, new)		__cmpxchg(ptr, old, new, smp_mb__before_llsc(), smp_llsc_mb())
-#define cmpxchg_local(ptr, old, new)	__cmpxchg(ptr, old, new, , )
-
 #ifdef CONFIG_64BIT
 #define cmpxchg64_local(ptr, o, n)					\
   ({									\
@@ -245,4 +205,6 @@ extern void __cmpxchg_called_with_bad_pointer(void);
 #define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n))
 #endif
 
+#undef __scbeqz
+
 #endif /* __ASM_CMPXCHG_H */