Merge tag 'for-linus' of git://github.com/openrisc/linux

Pull OpenRISC updates from Stafford Horne:
 "The OpenRISC work is a bit more interesting this time, adding SMP
  support and a few general cleanups.

  Small Things:

   - Move OpenRISC docs into Documentation and clean them up

   - Document previously undocumented devicetree bindings

   - Update the or1ksim dts to use stdout-path

  OpenRISC SMP support details:

   - First the "use shadow registers" and "define CPU_BIG_ENDIAN as
     true" get the architecture ready for SMP.

   - The "add 1 and 2 byte cmpxchg support" and "use qspinlocks and
     qrwlocks" add the SMP locking infrastructure as needed. Using the
     qspinlocks and qrwlocks as suggested by Peter Z while reviewing the
     original spinlocks implementation.

   - The "support for ompic" adds a new irqchip device which is used for
     IPI communication to support SMP.

   - The "initial SMP support" adds smp.c and makes changes to all of
     the necessary data-structures to be per-cpu.

  The remaining patches are bug fixes and debug helpers which I wanted
  to keep separate from the "initial SMP support" in order to allow them
  to be reviewed on their own. This includes:

   - add cacheflush support to fix icache aliasing

   - fix initial preempt state for secondary cpu tasks

   - sleep instead of spin on secondary wait

   - support framepointers and STACKTRACE_SUPPORT

   - enable LOCKDEP_SUPPORT and irqflags tracing

   - timer sync: Add tick timer sync logic

   - fix possible deadlock in timer sync, pointed out by mips guys

  Note: the irqchip patch was reviewed with Marc and we agreed to push
  it together with these patches"

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: fix possible deadlock scenario during timer sync
  openrisc: pass endianness info to sparse
  openrisc: add tick timer multi-core sync logic
  openrisc: enable LOCKDEP_SUPPORT and irqflags tracing
  openrisc: support framepointers and STACKTRACE_SUPPORT
  openrisc: add simple_smp dts and defconfig for simulators
  openrisc: add cacheflush support to fix icache aliasing
  openrisc: sleep instead of spin on secondary wait
  openrisc: fix initial preempt state for secondary cpu tasks
  openrisc: initial SMP support
  irqchip: add initial support for ompic
  dt-bindings: add openrisc to vendor prefixes list
  openrisc: use qspinlocks and qrwlocks
  openrisc: add 1 and 2 byte cmpxchg support
  openrisc: use shadow registers to save regs on exception
  dt-bindings: openrisc: Add OpenRISC platform SoC
  Documentation: openrisc: Updates to README
  Documentation: Move OpenRISC docs out of arch/
  MAINTAINERS: Add OpenRISC pic maintainer
  openrisc: dts: or1ksim: Add stdout-path

Documentation/devicetree/bindings/interrupt-controller/openrisc,ompic.txt

@@ -0,0 +1,22 @@
+Open Multi-Processor Interrupt Controller
+
+Required properties:
+
+- compatible : This should be "openrisc,ompic"
+- reg : Specifies base physical address and size of the register space. The
+  size is based on the number of cores the controller has been configured
+  to handle, this should be set to 8 bytes per cpu core.
+- interrupt-controller : Identifies the node as an interrupt controller.
+- #interrupt-cells : This should be set to 0 as this will not be an irq
+  parent.
+- interrupts : Specifies the interrupt line to which the ompic is wired.
+
+Example:
+
+ompic: interrupt-controller@98000000 {
+	compatible = "openrisc,ompic";
+	reg = <0x98000000 16>;
+	interrupt-controller;
+	#interrupt-cells = <0>;
+	interrupts = <1>;
+};

Documentation/devicetree/bindings/openrisc/opencores/or1ksim.txt

@@ -0,0 +1,39 @@
+OpenRISC Generic SoC
+====================
+
+Boards and FPGA SoC's which support the OpenRISC standard platform.  The
+platform essentially follows the conventions of the OpenRISC architecture
+specification, however some aspects, such as the boot protocol have been defined
+by the Linux port.
+
+Required properties
+-------------------
+ - compatible: Must include "opencores,or1ksim"
+
+CPU nodes:
+----------
+A "cpus" node is required.  Required properties:
+ - #address-cells: Must be 1.
+ - #size-cells: Must be 0.
+A CPU sub-node is also required for at least CPU 0.  Since the topology may
+be probed via CPS, it is not necessary to specify secondary CPUs.  Required
+properties:
+ - compatible: Must be "opencores,or1200-rtlsvn481".
+ - reg: CPU number.
+ - clock-frequency: The CPU clock frequency in Hz.
+Example:
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		cpu@0 {
+			compatible = "opencores,or1200-rtlsvn481";
+			reg = <0>;
+			clock-frequency = <20000000>;
+		};
+	};
+
+
+Boot protocol
+-------------
+The bootloader may pass the following arguments to the kernel:
+ - r3:  address of a flattened device-tree blob or 0x0.

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -246,6 +246,7 @@ onion	Onion Corporation
 onnn	ON Semiconductor Corp.
 ontat	On Tat Industrial Company
 opencores	OpenCores.org
+openrisc	OpenRISC.io
 option	Option NV
 ORCL	Oracle Corporation
 ortustech	Ortus Technology Co., Ltd.

Documentation/openrisc/README

@@ -7,13 +7,7 @@ target architecture, specifically, is the 32-bit OpenRISC 1000 family (or1k).
 For information about OpenRISC processors and ongoing development:
 
 	website		http://openrisc.io
-
+	email		openrisc@lists.librecores.org
-For more information about Linux on OpenRISC, please contact South Pole AB.
-
-	email:		info@southpole.se
-
-	website:	http://southpole.se
-			http://southpoleconsulting.com
 
 ---------------------------------------------------------------------
 
@@ -24,37 +18,54 @@ In order to build and run Linux for OpenRISC, you'll need at least a basic
 toolchain and, perhaps, the architectural simulator.  Steps to get these bits
 in place are outlined here.
 
-1)  The toolchain can be obtained from openrisc.io.  Instructions for building
+1) Toolchain
-a toolchain can be found at:
 
-https://github.com/openrisc/tutorials
+Toolchain binaries can be obtained from openrisc.io or our github releases page.
+Instructions for building the different toolchains can be found on openrisc.io
+or Stafford's toolchain build and release scripts.
 
-2) or1ksim (optional)
+	binaries	https://github.com/openrisc/or1k-gcc/releases
+	toolchains	https://openrisc.io/software
+	building	https://github.com/stffrdhrn/or1k-toolchain-build
 
-or1ksim is the architectural simulator which will allow you to actually run
+2) Building
-your OpenRISC Linux kernel if you don't have an OpenRISC processor at hand.
 
-	git clone https://github.com/openrisc/or1ksim.git
+Build the Linux kernel as usual
-
-	cd or1ksim
-	./configure --prefix=$OPENRISC_PREFIX
-	make
-	make install
-
-3)  Linux kernel
-
-Build the kernel as usual
 
 	make ARCH=openrisc defconfig
 	make ARCH=openrisc
 
-4)  Run in architectural simulator
+3) Running on FPGA (optional)
 
-Grab the or1ksim platform configuration file (from the or1ksim source) and
+The OpenRISC community typically uses FuseSoC to manage building and programming
-together with your freshly built vmlinux, run your kernel with the following
+an SoC into an FPGA.  The below is an example of programming a De0 Nano
-incantation:
+development board with the OpenRISC SoC.  During the build FPGA RTL is code
+downloaded from the FuseSoC IP cores repository and built using the FPGA vendor
+tools.  Binaries are loaded onto the board with openocd.
 
-	sim -f arch/openrisc/or1ksim.cfg vmlinux
+	git clone https://github.com/olofk/fusesoc
+	cd fusesoc
+	sudo pip install -e .
+
+	fusesoc init
+	fusesoc build de0_nano
+	fusesoc pgm de0_nano
+
+	openocd -f interface/altera-usb-blaster.cfg \
+		-f board/or1k_generic.cfg
+
+	telnet localhost 4444
+	> init
+	> halt; load_image vmlinux ; reset
+
+4) Running on a Simulator (optional)
+
+QEMU is a processor emulator which we recommend for simulating the OpenRISC
+platform.  Please follow the OpenRISC instructions on the QEMU website to get
+Linux running on QEMU.  You can build QEMU yourself, but your Linux distribution
+likely provides binary packages to support OpenRISC.
+
+	qemu openrisc	https://wiki.qemu.org/Documentation/Platforms/OpenRISC
 
 ---------------------------------------------------------------------
 

MAINTAINERS

@@ -10037,7 +10037,11 @@ T:	git git://github.com/openrisc/linux.git
 L:	openrisc@lists.librecores.org
 W:	http://openrisc.io
 S:	Maintained
+F:	Documentation/devicetree/bindings/openrisc/
+F:	Documentation/openrisc/
 F:	arch/openrisc/
+F:	drivers/irqchip/irq-ompic.c
+F:	drivers/irqchip/irq-or1k-*
 
 OPENVSWITCH
 M:	Pravin Shelar <pshelar@nicira.com>

arch/openrisc/Kconfig

@@ -22,13 +22,19 @@ config OPENRISC
 	select HAVE_UID16
 	select GENERIC_ATOMIC64
 	select GENERIC_CLOCKEVENTS
+	select GENERIC_CLOCKEVENTS_BROADCAST
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
+	select GENERIC_SMP_IDLE_THREAD
 	select MODULES_USE_ELF_RELA
 	select HAVE_DEBUG_STACKOVERFLOW
 	select OR1K_PIC
 	select CPU_NO_EFFICIENT_FFS if !OPENRISC_HAVE_INST_FF1
 	select NO_BOOTMEM
+	select ARCH_USE_QUEUED_SPINLOCKS
+	select ARCH_USE_QUEUED_RWLOCKS
+	select OMPIC if SMP
+	select ARCH_WANT_FRAME_POINTERS
 
 config CPU_BIG_ENDIAN
 	def_bool y
@@ -56,6 +62,12 @@ config TRACE_IRQFLAGS_SUPPORT
 config GENERIC_CSUM
         def_bool y
 
+config STACKTRACE_SUPPORT
+	def_bool y
+
+config LOCKDEP_SUPPORT
+	def_bool  y
+
 source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"
@@ -73,6 +85,17 @@ config OR1K_1200
 
 endchoice
 
+config DCACHE_WRITETHROUGH
+	bool "Have write through data caches"
+	default n
+	help
+	  Select this if your implementation features write through data caches.
+	  Selecting 'N' here will allow the kernel to force flushing of data
+	  caches at relevant times. Most OpenRISC implementations support write-
+	  through data caches.
+
+	  If unsure say N here
+
 config OPENRISC_BUILTIN_DTB
         string "Builtin DTB"
         default ""
@@ -105,8 +128,19 @@ config OPENRISC_HAVE_INST_DIV
 endmenu
 
 config NR_CPUS
-	int
+	int "Maximum number of CPUs (2-32)"
-	default "1"
+	range 2 32
+	depends on SMP
+	default "2"
+
+config SMP
+	bool "Symmetric Multi-Processing support"
+	help
+	  This enables support for systems with more than one CPU. If you have
+	  a system with only one CPU, say N. If you have a system with more
+	  than one CPU, say Y.
+
+	  If you don't know what to do here, say N.
 
 source kernel/Kconfig.hz
 source kernel/Kconfig.preempt
@@ -125,6 +159,17 @@ config OPENRISC_NO_SPR_SR_DSX
 	  Say N here if you know that your OpenRISC processor has
 	  SPR_SR_DSX bit implemented. Say Y if you are unsure.
 
+config OPENRISC_HAVE_SHADOW_GPRS
+	bool "Support for shadow gpr files" if !SMP
+	default y if SMP
+	help
+	  Say Y here if your OpenRISC processor features shadowed
+	  register files. They will in such case be used as a
+	  scratch reg storage on exception entry.
+
+	  On SMP systems, this feature is mandatory.
+	  On a unicore system it's safe to say N here if you are unsure.
+
 config CMDLINE
         string "Default kernel command string"
         default ""

arch/openrisc/Makefile

@@ -25,6 +25,7 @@ LDFLAGS_vmlinux :=
 LIBGCC 		:= $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name)
 
 KBUILD_CFLAGS	+= -pipe -ffixed-r10 -D__linux__
+CHECKFLAGS	+= -mbig-endian
 
 ifeq ($(CONFIG_OPENRISC_HAVE_INST_MUL),y)
 	KBUILD_CFLAGS += $(call cc-option,-mhard-mul)

arch/openrisc/boot/dts/or1ksim.dts

@@ -6,8 +6,13 @@
 	#size-cells = <1>;
 	interrupt-parent = <&pic>;
 
+	aliases {
+		uart0 = &serial0;
+	};
+
 	chosen {
-		bootargs = "console=uart,mmio,0x90000000,115200";
+		bootargs = "earlycon";
+		stdout-path = "uart0:115200";
 	};
 
 	memory@0 {

arch/openrisc/boot/dts/simple_smp.dts

@@ -0,0 +1,63 @@
+/dts-v1/;
+/ {
+	compatible = "opencores,or1ksim";
+	#address-cells = <1>;
+	#size-cells = <1>;
+	interrupt-parent = <&pic>;
+
+	aliases {
+		uart0 = &serial0;
+	};
+
+	chosen {
+		bootargs = "earlycon";
+		stdout-path = "uart0:115200";
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x00000000 0x02000000>;
+	};
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		cpu@0 {
+			compatible = "opencores,or1200-rtlsvn481";
+			reg = <0>;
+			clock-frequency = <20000000>;
+		};
+		cpu@1 {
+			compatible = "opencores,or1200-rtlsvn481";
+			reg = <1>;
+			clock-frequency = <20000000>;
+		};
+	};
+
+	ompic: ompic@98000000 {
+		compatible = "openrisc,ompic";
+		reg = <0x98000000 16>;
+		interrupt-controller;
+		#interrupt-cells = <0>;
+		interrupts = <1>;
+	};
+
+	/*
+	 * OR1K PIC is built into CPU and accessed via special purpose
+	 * registers.  It is not addressable and, hence, has no 'reg'
+	 * property.
+	 */
+	pic: pic {
+		compatible = "opencores,or1k-pic-level";
+		#interrupt-cells = <1>;
+		interrupt-controller;
+	};
+
+	serial0: serial@90000000 {
+		compatible = "opencores,uart16550-rtlsvn105", "ns16550a";
+		reg = <0x90000000 0x100>;
+		interrupts = <2>;
+		clock-frequency = <20000000>;
+	};
+
+};

arch/openrisc/configs/simple_smp_defconfig

@@ -0,0 +1,66 @@
+CONFIG_CROSS_COMPILE="or1k-linux-"
+CONFIG_LOCALVERSION="-simple-smp"
+CONFIG_NO_HZ=y
+CONFIG_LOG_BUF_SHIFT=14
+CONFIG_BLK_DEV_INITRD=y
+# CONFIG_RD_GZIP is not set
+# CONFIG_RD_BZIP2 is not set
+# CONFIG_RD_LZMA is not set
+# CONFIG_RD_XZ is not set
+# CONFIG_RD_LZO is not set
+# CONFIG_RD_LZ4 is not set
+CONFIG_EXPERT=y
+# CONFIG_KALLSYMS is not set
+# CONFIG_EPOLL is not set
+# CONFIG_TIMERFD is not set
+# CONFIG_EVENTFD is not set
+# CONFIG_AIO is not set
+# CONFIG_VM_EVENT_COUNTERS is not set
+# CONFIG_COMPAT_BRK is not set
+CONFIG_SLOB=y
+CONFIG_MODULES=y
+# CONFIG_BLOCK is not set
+CONFIG_OPENRISC_BUILTIN_DTB="simple_smp"
+CONFIG_SMP=y
+CONFIG_HZ_100=y
+CONFIG_OPENRISC_HAVE_SHADOW_GPRS=y
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_INET=y
+# CONFIG_INET_XFRM_MODE_TRANSPORT is not set
+# CONFIG_INET_XFRM_MODE_TUNNEL is not set
+# CONFIG_INET_XFRM_MODE_BEET is not set
+# CONFIG_INET_DIAG is not set
+CONFIG_TCP_CONG_ADVANCED=y
+# CONFIG_TCP_CONG_BIC is not set
+# CONFIG_TCP_CONG_CUBIC is not set
+# CONFIG_TCP_CONG_WESTWOOD is not set
+# CONFIG_TCP_CONG_HTCP is not set
+# CONFIG_IPV6 is not set
+# CONFIG_WIRELESS is not set
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+# CONFIG_PREVENT_FIRMWARE_BUILD is not set
+# CONFIG_FW_LOADER is not set
+CONFIG_NETDEVICES=y
+CONFIG_ETHOC=y
+CONFIG_MICREL_PHY=y
+# CONFIG_WLAN is not set
+# CONFIG_INPUT is not set
+# CONFIG_SERIO is not set
+# CONFIG_VT is not set
+# CONFIG_LEGACY_PTYS is not set
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
+CONFIG_SERIAL_OF_PLATFORM=y
+# CONFIG_HW_RANDOM is not set
+# CONFIG_HWMON is not set
+# CONFIG_USB_SUPPORT is not set
+# CONFIG_DNOTIFY is not set
+CONFIG_TMPFS=y
+CONFIG_NFS_FS=y
+CONFIG_XZ_DEC=y
+# CONFIG_ENABLE_WARN_DEPRECATED is not set
+# CONFIG_ENABLE_MUST_CHECK is not set
+# CONFIG_RCU_TRACE is not set

arch/openrisc/include/asm/Kbuild

@@ -1,7 +1,6 @@
 generic-y += barrier.h
 generic-y += bug.h
 generic-y += bugs.h
-generic-y += cacheflush.h
 generic-y += checksum.h
 generic-y += clkdev.h
 generic-y += current.h
@@ -28,6 +27,10 @@ generic-y += module.h
 generic-y += pci.h
 generic-y += percpu.h
 generic-y += preempt.h
+generic-y += qspinlock_types.h
+generic-y += qspinlock.h
+generic-y += qrwlock_types.h
+generic-y += qrwlock.h
 generic-y += sections.h
 generic-y += segment.h
 generic-y += string.h

arch/openrisc/include/asm/cacheflush.h

@@ -0,0 +1,96 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
+ * et al.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_CACHEFLUSH_H
+#define __ASM_CACHEFLUSH_H
+
+#include <linux/mm.h>
+
+/*
+ * Helper function for flushing or invalidating entire pages from data
+ * and instruction caches. SMP needs a little extra work, since we need
+ * to flush the pages on all cpus.
+ */
+extern void local_dcache_page_flush(struct page *page);
+extern void local_icache_page_inv(struct page *page);
+
+/*
+ * Data cache flushing always happen on the local cpu. Instruction cache
+ * invalidations need to be broadcasted to all other cpu in the system in
+ * case of SMP configurations.
+ */
+#ifndef CONFIG_SMP
+#define dcache_page_flush(page)      local_dcache_page_flush(page)
+#define icache_page_inv(page)        local_icache_page_inv(page)
+#else  /* CONFIG_SMP */
+#define dcache_page_flush(page)      local_dcache_page_flush(page)
+#define icache_page_inv(page)        smp_icache_page_inv(page)
+extern void smp_icache_page_inv(struct page *page);
+#endif /* CONFIG_SMP */
+
+/*
+ * Synchronizes caches. Whenever a cpu writes executable code to memory, this
+ * should be called to make sure the processor sees the newly written code.
+ */
+static inline void sync_icache_dcache(struct page *page)
+{
+	if (!IS_ENABLED(CONFIG_DCACHE_WRITETHROUGH))
+		dcache_page_flush(page);
+	icache_page_inv(page);
+}
+
+/*
+ * Pages with this bit set need not be flushed/invalidated, since
+ * they have not changed since last flush. New pages start with
+ * PG_arch_1 not set and are therefore dirty by default.
+ */
+#define PG_dc_clean                  PG_arch_1
+
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
+static inline void flush_dcache_page(struct page *page)
+{
+	clear_bit(PG_dc_clean, &page->flags);
+}
+
+/*
+ * Other interfaces are not required since we do not have virtually
+ * indexed or tagged caches. So we can use the default here.
+ */
+#define flush_cache_all()				do { } while (0)
+#define flush_cache_mm(mm)				do { } while (0)
+#define flush_cache_dup_mm(mm)				do { } while (0)
+#define flush_cache_range(vma, start, end)		do { } while (0)
+#define flush_cache_page(vma, vmaddr, pfn)		do { } while (0)
+#define flush_dcache_mmap_lock(mapping)			do { } while (0)
+#define flush_dcache_mmap_unlock(mapping)		do { } while (0)
+#define flush_icache_range(start, end)			do { } while (0)
+#define flush_icache_page(vma, pg)			do { } while (0)
+#define flush_icache_user_range(vma, pg, adr, len)	do { } while (0)
+#define flush_cache_vmap(start, end)			do { } while (0)
+#define flush_cache_vunmap(start, end)			do { } while (0)
+
+#define copy_to_user_page(vma, page, vaddr, dst, src, len)           \
+	do {                                                         \
+		memcpy(dst, src, len);                               \
+		if (vma->vm_flags & VM_EXEC)                         \
+			sync_icache_dcache(page);                    \
+	} while (0)
+
+#define copy_from_user_page(vma, page, vaddr, dst, src, len)         \
+	memcpy(dst, src, len)
+
+#endif /* __ASM_CACHEFLUSH_H */

arch/openrisc/include/asm/cmpxchg.h

@@ -1,32 +1,29 @@
 /*
+ * 1,2 and 4 byte cmpxchg and xchg implementations for OpenRISC.
+ *
  * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
+ * Copyright (C) 2017 Stafford Horne <shorne@gmail.com>
  *
  * This file is licensed under the terms of the GNU General Public License
  * version 2.  This program is licensed "as is" without any warranty of any
  * kind, whether express or implied.
+ *
+ * Note:
+ * The portable implementations of 1 and 2 byte xchg and cmpxchg using a 4
+ * byte cmpxchg is sourced heavily from the sh and mips implementations.
  */
 
 #ifndef __ASM_OPENRISC_CMPXCHG_H
 #define __ASM_OPENRISC_CMPXCHG_H
 
 #include  <linux/types.h>
-
+#include  <linux/bitops.h>
-/*
- * 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);
 
 #define __HAVE_ARCH_CMPXCHG 1
 
-static inline unsigned long
+static inline unsigned long cmpxchg_u32(volatile void *ptr,
-__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
+		unsigned long old, unsigned long new)
 {
-	if (size != 4) {
-		__cmpxchg_called_with_bad_pointer();
-		return old;
-	}
-
 	__asm__ __volatile__(
 		"1:	l.lwa %0, 0(%1)		\n"
 		"	l.sfeq %0, %2		\n"
@@ -43,28 +40,9 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
 	return old;
 }
 
-#define cmpxchg(ptr, o, n)						\
+static inline unsigned long xchg_u32(volatile void *ptr,
-	({								\
+		unsigned long val)
-		(__typeof__(*(ptr))) __cmpxchg((ptr),			\
-					       (unsigned long)(o),	\
-					       (unsigned long)(n),	\
-					       sizeof(*(ptr)));		\
-	})
-
-/*
- * This function doesn't exist, so you'll get a linker error if
- * something tries to do an invalidly-sized xchg().
- */
-extern void __xchg_called_with_bad_pointer(void);
-
-static inline unsigned long __xchg(unsigned long val, volatile void *ptr,
-				   int size)
 {
-	if (size != 4) {
-		__xchg_called_with_bad_pointer();
-		return val;
-	}
-
 	__asm__ __volatile__(
 		"1:	l.lwa %0, 0(%1)		\n"
 		"	l.swa 0(%1), %2		\n"
@@ -77,10 +55,115 @@ static inline unsigned long __xchg(unsigned long val, volatile void *ptr,
 	return val;
 }
 
+static inline u32 cmpxchg_small(volatile void *ptr, u32 old, u32 new,
+				int size)
+{
+	int off = (unsigned long)ptr % sizeof(u32);
+	volatile u32 *p = ptr - off;
+#ifdef __BIG_ENDIAN
+	int bitoff = (sizeof(u32) - size - off) * BITS_PER_BYTE;
+#else
+	int bitoff = off * BITS_PER_BYTE;
+#endif
+	u32 bitmask = ((0x1 << size * BITS_PER_BYTE) - 1) << bitoff;
+	u32 load32, old32, new32;
+	u32 ret;
+
+	load32 = READ_ONCE(*p);
+
+	while (true) {
+		ret = (load32 & bitmask) >> bitoff;
+		if (old != ret)
+			return ret;
+
+		old32 = (load32 & ~bitmask) | (old << bitoff);
+		new32 = (load32 & ~bitmask) | (new << bitoff);
+
+		/* Do 32 bit cmpxchg */
+		load32 = cmpxchg_u32(p, old32, new32);
+		if (load32 == old32)
+			return old;
+	}
+}
+
+/* xchg */
+
+static inline u32 xchg_small(volatile void *ptr, u32 x, int size)
+{
+	int off = (unsigned long)ptr % sizeof(u32);
+	volatile u32 *p = ptr - off;
+#ifdef __BIG_ENDIAN
+	int bitoff = (sizeof(u32) - size - off) * BITS_PER_BYTE;
+#else
+	int bitoff = off * BITS_PER_BYTE;
+#endif
+	u32 bitmask = ((0x1 << size * BITS_PER_BYTE) - 1) << bitoff;
+	u32 oldv, newv;
+	u32 ret;
+
+	do {
+		oldv = READ_ONCE(*p);
+		ret = (oldv & bitmask) >> bitoff;
+		newv = (oldv & ~bitmask) | (x << bitoff);
+	} while (cmpxchg_u32(p, oldv, newv) != oldv);
+
+	return ret;
+}
+
+/*
+ * This function doesn't exist, so you'll get a linker error
+ * if something tries to do an invalid cmpxchg().
+ */
+extern unsigned long __cmpxchg_called_with_bad_pointer(void)
+	__compiletime_error("Bad argument size for cmpxchg");
+
+static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
+		unsigned long new, int size)
+{
+	switch (size) {
+	case 1:
+	case 2:
+		return cmpxchg_small(ptr, old, new, size);
+	case 4:
+		return cmpxchg_u32(ptr, old, new);
+	default:
+		return __cmpxchg_called_with_bad_pointer();
+	}
+}
+
+#define cmpxchg(ptr, o, n)						\
+	({								\
+		(__typeof__(*(ptr))) __cmpxchg((ptr),			\
+					       (unsigned long)(o),	\
+					       (unsigned long)(n),	\
+					       sizeof(*(ptr)));		\
+	})
+
+/*
+ * This function doesn't exist, so you'll get a linker error if
+ * something tries to do an invalidly-sized xchg().
+ */
+extern unsigned long __xchg_called_with_bad_pointer(void)
+	__compiletime_error("Bad argument size for xchg");
+
+static inline unsigned long __xchg(volatile void *ptr, unsigned long with,
+		int size)
+{
+	switch (size) {
+	case 1:
+	case 2:
+		return xchg_small(ptr, with, size);
+	case 4:
+		return xchg_u32(ptr, with);
+	default:
+		return __xchg_called_with_bad_pointer();
+	}
+}
+
 #define xchg(ptr, with) 						\
 	({								\
-		(__typeof__(*(ptr))) __xchg((unsigned long)(with),	\
+		(__typeof__(*(ptr))) __xchg((ptr),			\
-					    (ptr),			\
+					    (unsigned long)(with),	\
 					    sizeof(*(ptr)));		\
 	})
 

arch/openrisc/include/asm/cpuinfo.h

@@ -19,7 +19,7 @@
 #ifndef __ASM_OPENRISC_CPUINFO_H
 #define __ASM_OPENRISC_CPUINFO_H
 
-struct cpuinfo {
+struct cpuinfo_or1k {
 	u32 clock_frequency;
 
 	u32 icache_size;
@@ -29,8 +29,11 @@ struct cpuinfo {
 	u32 dcache_size;
 	u32 dcache_block_size;
 	u32 dcache_ways;
+
+	u16 coreid;
 };
 
-extern struct cpuinfo cpuinfo;
+extern struct cpuinfo_or1k cpuinfo_or1k[NR_CPUS];
+extern void setup_cpuinfo(void);
 
 #endif /* __ASM_OPENRISC_CPUINFO_H */

arch/openrisc/include/asm/mmu_context.h

@@ -34,7 +34,7 @@ extern void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  * registers like cr3 on the i386
  */
 
-extern volatile pgd_t *current_pgd;   /* defined in arch/openrisc/mm/fault.c */
+extern volatile pgd_t *current_pgd[]; /* defined in arch/openrisc/mm/fault.c */
 
 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
 {

arch/openrisc/include/asm/pgtable.h

@@ -94,7 +94,7 @@ extern void paging_init(void);
  * 64 MB of vmalloc area is comparable to what's available on other arches.
  */
 
-#define VMALLOC_START	(PAGE_OFFSET-0x04000000)
+#define VMALLOC_START	(PAGE_OFFSET-0x04000000UL)
 #define VMALLOC_END	(PAGE_OFFSET)
 #define VMALLOC_VMADDR(x) ((unsigned long)(x))
 
@@ -416,15 +416,19 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* defined in head.S */
 
 struct vm_area_struct;
 
-/*
+static inline void update_tlb(struct vm_area_struct *vma,
- * or32 doesn't have any external MMU info: the kernel page
+	unsigned long address, pte_t *pte)
- * tables contain all the necessary information.
+{
- *
+}
- * Actually I am not sure on what this could be used for.
+
- */
+extern void update_cache(struct vm_area_struct *vma,
+	unsigned long address, pte_t *pte);
+
 static inline void update_mmu_cache(struct vm_area_struct *vma,
 	unsigned long address, pte_t *pte)
 {
+	update_tlb(vma, address, pte);
+	update_cache(vma, address, pte);
 }
 
 /* __PHX__ FIXME, SWAP, this probably doesn't work */

arch/openrisc/include/asm/serial.h

@@ -29,7 +29,7 @@
  * it needs to be correct to get the early console working.
  */
 
-#define BASE_BAUD (cpuinfo.clock_frequency/16)
+#define BASE_BAUD (cpuinfo_or1k[smp_processor_id()].clock_frequency/16)
 
 #endif /* __KERNEL__ */
 

arch/openrisc/include/asm/smp.h

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2.  This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#ifndef __ASM_OPENRISC_SMP_H
+#define __ASM_OPENRISC_SMP_H
+
+#include <asm/spr.h>
+#include <asm/spr_defs.h>
+
+#define raw_smp_processor_id()	(current_thread_info()->cpu)
+#define hard_smp_processor_id()	mfspr(SPR_COREID)
+
+extern void smp_init_cpus(void);
+
+extern void arch_send_call_function_single_ipi(int cpu);
+extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
+
+extern void set_smp_cross_call(void (*)(const struct cpumask *, unsigned int));
+extern void handle_IPI(unsigned int ipi_msg);
+
+#endif /* __ASM_OPENRISC_SMP_H */

arch/openrisc/include/asm/spinlock.h

@@ -19,6 +19,16 @@
 #ifndef __ASM_OPENRISC_SPINLOCK_H
 #define __ASM_OPENRISC_SPINLOCK_H
 
-#error "or32 doesn't do SMP yet"
+#include <asm/qspinlock.h>
+
+#include <asm/qrwlock.h>
+
+#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
+#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
+
+#define arch_spin_relax(lock)	cpu_relax()
+#define arch_read_relax(lock)	cpu_relax()
+#define arch_write_relax(lock)	cpu_relax()
+
 
 #endif