Merge tag 'arc-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC updates from Vineet Gupta:
 "We have a relatively big changeset for ARC for 4.7.

  The highlight is support for EZChip (now Mellanox) NPS-400 network
  processor, a 400-Gb throughput C-programmable packet processor based
  on ARC700 cores from Synopsys. See

        http://www.mellanox.com/related-docs/prod_npu/PB_NPS-400.pdf

  Also present are irqchip and clocksource drivers for NPS as agreed
  with respective maintainers to go via ARC tree due to an soc header
  dependency.  I have the needed ACKs from Jason, Marc, Daniel.  You
  might run into a trivial merge conflict in drivers/irqchip/*

  This EZChip platform support required some deep changes in ARC
  architecture code and also opportunity to cleanup past sins (legacy
  irq domains, missing irq domain lookup, hard coded timer irqs...)

  Summary:

   - Support for EZChip (now Mellanox) NPS-400 Network processor based
     on ARC700

   - NPS interrupt controller and clocksource drivers

   - ARC timers probed off DT

   - ARC iqrchips switching to linear domain (upgrade from legacy
     domains)"

* tag 'arc-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (37 commits)
  arc: axs103_smp: Fix CPU frequency to 100MHz for dual-core
  arc: axs10x: Add DT bindings for I2S PLL Clock
  ARC: pae: STRICT_MM_TYPECHECKS was broken
  ARC: Add eznps platform to Kconfig and Makefile
  ARC: [plat-eznps] Use dedicated COMMAND_LINE_SIZE
  ARC: [plat-eznps] Use dedicated cpu_relax()
  ARC: [plat-eznps] Use dedicated identity auxiliary register.
  ARC: [plat-eznps] Use dedicated SMP barriers
  ARC: [plat-eznps] Use dedicated atomic/bitops/cmpxchg
  ARC: [plat-eznps] Use dedicated user stack top
  ARC: [plat-eznps] Add eznps platform
  ARC: [plat-eznps] Add eznps board defconfig and dts
  ARC: Mark secondary cpu online only after all HW setup is done
  ARC: rwlock: disable interrupts in !LLSC variant
  ARC: Make vmalloc size configurable
  ARC: clean out UAPI byteorder.h clean off Kconfig symbol
  irqchip: add nps Internal and external irqchips
  clocksource: Add NPS400 timers driver
  soc: Support for EZchip SoC
  Documentation: Add EZchip vendor to binding list
  ...

1 files changed, 68 insertions, 8 deletions

diff --git a/arch/arc/include/asm/cmpxchg.h b/arch/arc/include/asm/cmpxchg.h
index a444be67cd53..d819de1c5d10 100644
--- a/arch/arc/include/asm/cmpxchg.h
+++ b/arch/arc/include/asm/cmpxchg.h
@@ -44,7 +44,7 @@ __cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
 	return prev;
 }
 
-#else
+#elif !defined(CONFIG_ARC_PLAT_EZNPS)
 
 static inline unsigned long
 __cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
@@ -64,23 +64,48 @@ __cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
 	return prev;
 }
 
+#else /* CONFIG_ARC_PLAT_EZNPS */
+
+static inline unsigned long
+__cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
+{
+	/*
+	 * Explicit full memory barrier needed before/after
+	 */
+	smp_mb();
+
+	write_aux_reg(CTOP_AUX_GPA1, expected);
+
+	__asm__ __volatile__(
+	"	mov r2, %0\n"
+	"	mov r3, %1\n"
+	"	.word %2\n"
+	"	mov %0, r2"
+	: "+r"(new)
+	: "r"(ptr), "i"(CTOP_INST_EXC_DI_R2_R2_R3)
+	: "r2", "r3", "memory");
+
+	smp_mb();
+
+	return new;
+}
+
 #endif /* CONFIG_ARC_HAS_LLSC */
 
 #define cmpxchg(ptr, o, n) ((typeof(*(ptr)))__cmpxchg((ptr), \
 				(unsigned long)(o), (unsigned long)(n)))
 
 /*
- * Since not supported natively, ARC cmpxchg() uses atomic_ops_lock (UP/SMP)
- * just to gaurantee semantics.
- * atomic_cmpxchg() needs to use the same locks as it's other atomic siblings
- * which also happens to be atomic_ops_lock.
- *
- * Thus despite semantically being different, implementation of atomic_cmpxchg()
- * is same as cmpxchg().
+ * atomic_cmpxchg is same as cmpxchg
+ *   LLSC: only different in data-type, semantics are exactly same
+ *  !LLSC: cmpxchg() has to use an external lock atomic_ops_lock to guarantee
+ *         semantics, and this lock also happens to be used by atomic_*()
  */
 #define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
 
 
+#ifndef CONFIG_ARC_PLAT_EZNPS
+
 /*
  * xchg (reg with memory) based on "Native atomic" EX insn
  */
@@ -143,6 +168,41 @@ static inline unsigned long __xchg(unsigned long val, volatile void *ptr,
 
 #endif
 
+#else /* CONFIG_ARC_PLAT_EZNPS */
+
+static inline unsigned long __xchg(unsigned long val, volatile void *ptr,
+				   int size)
+{
+	extern unsigned long __xchg_bad_pointer(void);
+
+	switch (size) {
+	case 4:
+		/*
+		 * Explicit full memory barrier needed before/after
+		 */
+		smp_mb();
+
+		__asm__ __volatile__(
+		"	mov r2, %0\n"
+		"	mov r3, %1\n"
+		"	.word %2\n"
+		"	mov %0, r2\n"
+		: "+r"(val)
+		: "r"(ptr), "i"(CTOP_INST_XEX_DI_R2_R2_R3)
+		: "r2", "r3", "memory");
+
+		smp_mb();
+
+		return val;
+	}
+	return __xchg_bad_pointer();
+}
+
+#define xchg(ptr, with) ((typeof(*(ptr)))__xchg((unsigned long)(with), (ptr), \
+						 sizeof(*(ptr))))
+
+#endif /* CONFIG_ARC_PLAT_EZNPS */
+
 /*
  * "atomic" variant of xchg()
  * REQ: It needs to follow the same serialization rules as other atomic_xxx()