Merge branches 'debug-choice', 'devel-stable' and 'misc' into for-linus

Documentation/arm/Booting

@@ -18,7 +18,8 @@ following:
 2. Initialise one serial port.
 3. Detect the machine type.
 4. Setup the kernel tagged list.
-5. Call the kernel image.
+5. Load initramfs.
+6. Call the kernel image.
 
 
 1. Setup and initialise RAM
@@ -120,12 +121,27 @@ tagged list.
 The boot loader must pass at a minimum the size and location of the
 system memory, and the root filesystem location.  The dtb must be
 placed in a region of memory where the kernel decompressor will not
-overwrite it.  The recommended placement is in the first 16KiB of RAM
-with the caveat that it may not be located at physical address 0 since
-the kernel interprets a value of 0 in r2 to mean neither a tagged list
-nor a dtb were passed.
+overwrite it, whilst remaining within the region which will be covered
+by the kernel's low-memory mapping.
 
-5. Calling the kernel image
+A safe location is just above the 128MiB boundary from start of RAM.
+
+5. Load initramfs.
+------------------
+
+Existing boot loaders:		OPTIONAL
+New boot loaders:		OPTIONAL
+
+If an initramfs is in use then, as with the dtb, it must be placed in
+a region of memory where the kernel decompressor will not overwrite it
+while also with the region which will be covered by the kernel's
+low-memory mapping.
+
+A safe location is just above the device tree blob which itself will
+be loaded just above the 128MiB boundary from the start of RAM as
+recommended above.
+
+6. Calling the kernel image
 ---------------------------
 
 Existing boot loaders:		MANDATORY
@@ -136,11 +152,17 @@ is stored in flash, and is linked correctly to be run from flash,
 then it is legal for the boot loader to call the zImage in flash
 directly.
 
-The zImage may also be placed in system RAM (at any location) and
-called there.  Note that the kernel uses 16K of RAM below the image
-to store page tables.  The recommended placement is 32KiB into RAM.
+The zImage may also be placed in system RAM and called there.  The
+kernel should be placed in the first 128MiB of RAM.  It is recommended
+that it is loaded above 32MiB in order to avoid the need to relocate
+prior to decompression, which will make the boot process slightly
+faster.
+
+When booting a raw (non-zImage) kernel the constraints are tighter.
+In this case the kernel must be loaded at an offset into system equal
+to TEXT_OFFSET - PAGE_OFFSET.
 
-In either case, the following conditions must be met:
+In any case, the following conditions must be met:
 
 - Quiesce all DMA capable devices so that memory does not get
   corrupted by bogus network packets or disk data. This will save

Documentation/arm/kernel_mode_neon.txt

@@ -0,0 +1,121 @@
+Kernel mode NEON
+================
+
+TL;DR summary
+-------------
+* Use only NEON instructions, or VFP instructions that don't rely on support
+  code
+* Isolate your NEON code in a separate compilation unit, and compile it with
+  '-mfpu=neon -mfloat-abi=softfp'
+* Put kernel_neon_begin() and kernel_neon_end() calls around the calls into your
+  NEON code
+* Don't sleep in your NEON code, and be aware that it will be executed with
+  preemption disabled
+
+
+Introduction
+------------
+It is possible to use NEON instructions (and in some cases, VFP instructions) in
+code that runs in kernel mode. However, for performance reasons, the NEON/VFP
+register file is not preserved and restored at every context switch or taken
+exception like the normal register file is, so some manual intervention is
+required. Furthermore, special care is required for code that may sleep [i.e.,
+may call schedule()], as NEON or VFP instructions will be executed in a
+non-preemptible section for reasons outlined below.
+
+
+Lazy preserve and restore
+-------------------------
+The NEON/VFP register file is managed using lazy preserve (on UP systems) and
+lazy restore (on both SMP and UP systems). This means that the register file is
+kept 'live', and is only preserved and restored when multiple tasks are
+contending for the NEON/VFP unit (or, in the SMP case, when a task migrates to
+another core). Lazy restore is implemented by disabling the NEON/VFP unit after
+every context switch, resulting in a trap when subsequently a NEON/VFP
+instruction is issued, allowing the kernel to step in and perform the restore if
+necessary.
+
+Any use of the NEON/VFP unit in kernel mode should not interfere with this, so
+it is required to do an 'eager' preserve of the NEON/VFP register file, and
+enable the NEON/VFP unit explicitly so no exceptions are generated on first
+subsequent use. This is handled by the function kernel_neon_begin(), which
+should be called before any kernel mode NEON or VFP instructions are issued.
+Likewise, the NEON/VFP unit should be disabled again after use to make sure user
+mode will hit the lazy restore trap upon next use. This is handled by the
+function kernel_neon_end().
+
+
+Interruptions in kernel mode
+----------------------------
+For reasons of performance and simplicity, it was decided that there shall be no
+preserve/restore mechanism for the kernel mode NEON/VFP register contents. This
+implies that interruptions of a kernel mode NEON section can only be allowed if
+they are guaranteed not to touch the NEON/VFP registers. For this reason, the
+following rules and restrictions apply in the kernel:
+* NEON/VFP code is not allowed in interrupt context;
+* NEON/VFP code is not allowed to sleep;
+* NEON/VFP code is executed with preemption disabled.
+
+If latency is a concern, it is possible to put back to back calls to
+kernel_neon_end() and kernel_neon_begin() in places in your code where none of
+the NEON registers are live. (Additional calls to kernel_neon_begin() should be
+reasonably cheap if no context switch occurred in the meantime)
+
+
+VFP and support code
+--------------------
+Earlier versions of VFP (prior to version 3) rely on software support for things
+like IEEE-754 compliant underflow handling etc. When the VFP unit needs such
+software assistance, it signals the kernel by raising an undefined instruction
+exception. The kernel responds by inspecting the VFP control registers and the
+current instruction and arguments, and emulates the instruction in software.
+
+Such software assistance is currently not implemented for VFP instructions
+executed in kernel mode. If such a condition is encountered, the kernel will
+fail and generate an OOPS.
+
+
+Separating NEON code from ordinary code
+---------------------------------------
+The compiler is not aware of the special significance of kernel_neon_begin() and
+kernel_neon_end(), i.e., that it is only allowed to issue NEON/VFP instructions
+between calls to these respective functions. Furthermore, GCC may generate NEON
+instructions of its own at -O3 level if -mfpu=neon is selected, and even if the
+kernel is currently compiled at -O2, future changes may result in NEON/VFP
+instructions appearing in unexpected places if no special care is taken.
+
+Therefore, the recommended and only supported way of using NEON/VFP in the
+kernel is by adhering to the following rules:
+* isolate the NEON code in a separate compilation unit and compile it with
+  '-mfpu=neon -mfloat-abi=softfp';
+* issue the calls to kernel_neon_begin(), kernel_neon_end() as well as the calls
+  into the unit containing the NEON code from a compilation unit which is *not*
+  built with the GCC flag '-mfpu=neon' set.
+
+As the kernel is compiled with '-msoft-float', the above will guarantee that
+both NEON and VFP instructions will only ever appear in designated compilation
+units at any optimization level.
+
+
+NEON assembler
+--------------
+NEON assembler is supported with no additional caveats as long as the rules
+above are followed.
+
+
+NEON code generated by GCC
+--------------------------
+The GCC option -ftree-vectorize (implied by -O3) tries to exploit implicit
+parallelism, and generates NEON code from ordinary C source code. This is fully
+supported as long as the rules above are followed.
+
+
+NEON intrinsics
+---------------
+NEON intrinsics are also supported. However, as code using NEON intrinsics
+relies on the GCC header <arm_neon.h>, (which #includes <stdint.h>), you should
+observe the following in addition to the rules above:
+* Compile the unit containing the NEON intrinsics with '-ffreestanding' so GCC
+  uses its builtin version of <stdint.h> (this is a C99 header which the kernel
+  does not supply);
+* Include <arm_neon.h> last, or at least after <linux/types.h>

Documentation/devicetree/bindings/arm/l2cc.txt

@@ -16,9 +16,11 @@ Required properties:
      performs the same operation).
 	"marvell,"aurora-outer-cache: Marvell Controller designed to be
 	 compatible with the ARM one with outer cache mode.
-	"bcm,bcm11351-a2-pl310-cache": For Broadcom bcm11351 chipset where an
+	"brcm,bcm11351-a2-pl310-cache": For Broadcom bcm11351 chipset where an
 	offset needs to be added to the address before passing down to the L2
 	cache controller
+	"bcm,bcm11351-a2-pl310-cache": DEPRECATED by
+	                               "brcm,bcm11351-a2-pl310-cache"
 - cache-unified : Specifies the cache is a unified cache.
 - cache-level : Should be set to 2 for a level 2 cache.
 - reg : Physical base address and size of cache controller's memory mapped

arch/arm/Kconfig

@@ -52,6 +52,7 @@ config ARM
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_UID16
+	select IRQ_FORCED_THREADING
 	select KTIME_SCALAR
 	select PERF_USE_VMALLOC
 	select RTC_LIB
@@ -1372,6 +1373,15 @@ config ARM_ERRATA_798181
 	  which sends an IPI to the CPUs that are running the same ASID
 	  as the one being invalidated.
 
+config ARM_ERRATA_773022
+	bool "ARM errata: incorrect instructions may be executed from loop buffer"
+	depends on CPU_V7
+	help
+	  This option enables the workaround for the 773022 Cortex-A15
+	  (up to r0p4) erratum. In certain rare sequences of code, the
+	  loop buffer may deliver incorrect instructions. This
+	  workaround disables the loop buffer to avoid the erratum.
+
 endmenu
 
 source "arch/arm/common/Kconfig"
@@ -1613,13 +1623,49 @@ config ARCH_NR_GPIO
 
 source kernel/Kconfig.preempt
 
-config HZ
+config HZ_FIXED
 	int
 	default 200 if ARCH_EBSA110 || ARCH_S3C24XX || ARCH_S5P64X0 || \
 		ARCH_S5PV210 || ARCH_EXYNOS4
 	default AT91_TIMER_HZ if ARCH_AT91
 	default SHMOBILE_TIMER_HZ if ARCH_SHMOBILE
-	default 100
+
+choice
+	depends on !HZ_FIXED
+	prompt "Timer frequency"
+
+config HZ_100
+	bool "100 Hz"
+
+config HZ_200
+	bool "200 Hz"
+
+config HZ_250
+	bool "250 Hz"
+
+config HZ_300
+	bool "300 Hz"
+
+config HZ_500
+	bool "500 Hz"
+
+config HZ_1000
+	bool "1000 Hz"
+
+endchoice
+
+config HZ
+	int
+	default HZ_FIXED if HZ_FIXED
+	default 100 if HZ_100
+	default 200 if HZ_200
+	default 250 if HZ_250
+	default 300 if HZ_300
+	default 500 if HZ_500
+	default 1000
+
+config SCHED_HRTICK
+	def_bool HIGH_RES_TIMERS
 
 config SCHED_HRTICK
 	def_bool HIGH_RES_TIMERS
@@ -1756,6 +1802,9 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE
        def_bool y
        depends on ARM_LPAE
 
+config ARCH_WANT_GENERAL_HUGETLB
+	def_bool y
+
 source "mm/Kconfig"
 
 config FORCE_MAX_ZONEORDER
@@ -2175,6 +2224,13 @@ config NEON
 	  Say Y to include support code for NEON, the ARMv7 Advanced SIMD
 	  Extension.
 
+config KERNEL_MODE_NEON
+	bool "Support for NEON in kernel mode"
+	default n
+	depends on NEON
+	help
+	  Say Y to include support for NEON in kernel mode.
+
 endmenu
 
 menu "Userspace binary formats"
@@ -2199,7 +2255,7 @@ source "kernel/power/Kconfig"
 
 config ARCH_SUSPEND_POSSIBLE
 	depends on !ARCH_S5PC100
-	depends on CPU_ARM920T || CPU_ARM926T || CPU_SA1100 || \
+	depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
 		CPU_V6 || CPU_V6K || CPU_V7 || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
 	def_bool y