Merge tag 'xtensa-for-next-20140815' into for_next

Xtensa improvements for 3.17:
- support highmem on cores with aliasing data cache. Enable highmem on kc705
  by default;
- simplify addition of new core variants (no need to modify Kconfig /
  Makefiles);
- improve robustness of unaligned access handler and its interaction with
  window overflow/underflow exception handlers;
- deprecate atomic and spill registers syscalls;
- clean up Kconfig: remove orphan MATH_EMULATION, sort 'select' statements;
- wire up renameat2 syscall.

Various fixes:
- fix address checks in dma_{alloc,free}_coherent (runtime BUG);
- fix access to THREAD_RA/THREAD_SP/THREAD_DS (debug build breakage);
- fix TLBTEMP_BASE_2 region handling in fast_second_level_miss (runtime
  unrecoverable exception);
- fix a6 and a7 handling in fast_syscall_xtensa (runtime userspace register
  clobbering);
- fix kernel/user jump out of fast_unaligned (potential runtime unrecoverable
  exception);
- replace termios IOCTL code definitions with constants (userspace build
  breakage).

Signed-off-by: Chris Zankel <chris@zankel.net>

24 files changed, 497 insertions, 217 deletions

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 3a617af60d46..49c6c3d94449 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -4,24 +4,23 @@ config ZONE_DMA
 config XTENSA
         def_bool y
         select ARCH_WANT_FRAME_POINTERS
-        select HAVE_IDE
-        select GENERIC_ATOMIC64
-        select GENERIC_CLOCKEVENTS
-        select VIRT_TO_BUS
-        select GENERIC_IRQ_SHOW
-        select GENERIC_SCHED_CLOCK
-        select MODULES_USE_ELF_RELA
-        select GENERIC_PCI_IOMAP
         select ARCH_WANT_IPC_PARSE_VERSION
         select ARCH_WANT_OPTIONAL_GPIOLIB
         select BUILDTIME_EXTABLE_SORT
         select CLONE_BACKWARDS
-        select IRQ_DOMAIN
-        select HAVE_OPROFILE
+        select COMMON_CLK
+        select GENERIC_ATOMIC64
+        select GENERIC_CLOCKEVENTS
+        select GENERIC_IRQ_SHOW
+        select GENERIC_PCI_IOMAP
+        select GENERIC_SCHED_CLOCK
         select HAVE_FUNCTION_TRACER
         select HAVE_IRQ_TIME_ACCOUNTING
+        select HAVE_OPROFILE
         select HAVE_PERF_EVENTS
-        select COMMON_CLK
+        select IRQ_DOMAIN
+        select MODULES_USE_ELF_RELA
+        select VIRT_TO_BUS
         help
           Xtensa processors are 32-bit RISC machines designed by Tensilica
           primarily for embedded systems.  These processors are both
@@ -62,7 +61,9 @@ config TRACE_IRQFLAGS_SUPPORT
         def_bool y
 
 config MMU
-        def_bool n
+        bool
+        default n if !XTENSA_VARIANT_CUSTOM
+        default XTENSA_VARIANT_MMU if XTENSA_VARIANT_CUSTOM
 
 config VARIANT_IRQ_SWITCH
         def_bool n
@@ -102,8 +103,40 @@ config XTENSA_VARIANT_S6000
         select VARIANT_IRQ_SWITCH
         select ARCH_REQUIRE_GPIOLIB
         select XTENSA_CALIBRATE_CCOUNT
+
+config XTENSA_VARIANT_CUSTOM
+        bool "Custom Xtensa processor configuration"
+        select MAY_HAVE_SMP
+        select HAVE_XTENSA_GPIO32
+        help
+          Select this variant to use a custom Xtensa processor configuration.
+          You will be prompted for a processor variant CORENAME.
 endchoice
 
+config XTENSA_VARIANT_CUSTOM_NAME
+        string "Xtensa Processor Custom Core Variant Name"
+        depends on XTENSA_VARIANT_CUSTOM
+        help
+          Provide the name of a custom Xtensa processor variant.
+          This CORENAME selects arch/xtensa/variant/CORENAME.
+          Dont forget you have to select MMU if you have one.
+
+config XTENSA_VARIANT_NAME
+        string
+        default "dc232b"                        if XTENSA_VARIANT_DC232B
+        default "dc233c"                        if XTENSA_VARIANT_DC233C
+        default "fsf"                           if XTENSA_VARIANT_FSF
+        default "s6000"                         if XTENSA_VARIANT_S6000
+        default XTENSA_VARIANT_CUSTOM_NAME      if XTENSA_VARIANT_CUSTOM
+
+config XTENSA_VARIANT_MMU
+        bool "Core variant has a Full MMU (TLB, Pages, Protection, etc)"
+        depends on XTENSA_VARIANT_CUSTOM
+        default y
+        help
+          Build a Conventional Kernel with full MMU support,
+          ie: it supports a TLB with auto-loading, page protection.
+
 config XTENSA_UNALIGNED_USER
         bool "Unaligned memory access in use space"
         help
@@ -156,13 +189,9 @@ config HOTPLUG_CPU
 
           Say N if you want to disable CPU hotplug.
 
-config MATH_EMULATION
-        bool "Math emulation"
-        help
-        Can we use information of configuration file?
-
 config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
         bool "Initialize Xtensa MMU inside the Linux kernel code"
+        depends on MMU
         default y
         help
           Earlier version initialized the MMU in the exception vector
@@ -192,6 +221,7 @@ config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
 
 config HIGHMEM
         bool "High Memory Support"
+        depends on MMU
         help
           Linux can use the full amount of RAM in the system by
           default. However, the default MMUv2 setup only maps the
@@ -208,6 +238,32 @@ config HIGHMEM
 
           If unsure, say Y.
 
+config FAST_SYSCALL_XTENSA
+        bool "Enable fast atomic syscalls"
+        default n
+        help
+          fast_syscall_xtensa is a syscall that can make atomic operations
+          on UP kernel when processor has no s32c1i support.
+
+          This syscall is deprecated. It may have issues when called with
+          invalid arguments. It is provided only for backwards compatibility.
+          Only enable it if your userspace software requires it.
+
+          If unsure, say N.
+
+config FAST_SYSCALL_SPILL_REGISTERS
+        bool "Enable spill registers syscall"
+        default n
+        help
+          fast_syscall_spill_registers is a syscall that spills all active
+          register windows of a calling userspace task onto its stack.
+
+          This syscall is deprecated. It may have issues when called with
+          invalid arguments. It is provided only for backwards compatibility.
+          Only enable it if your userspace software requires it.
+
+          If unsure, say N.
+