XIP (eXecute In Place) kernel image is the image that can be run
directly from ROM, using RAM only for writable data.

XIP xtensa kernel differs from regular xtensa kernel in the following
ways:
- it has exception/IRQ vectors merged into text section. No vectors
  relocation takes place at kernel startup.
- .data/.bss location must be specified in the kernel configuration,
  its content is copied there in the _startup function.
- .init.text is merged with the rest of text and is executed from ROM.
- when MMU is used the virtual address where the kernel will be mapped
  must be specified in the kernel configuration. It may be in the KSEG
  or in the KIO, __pa macro is adjusted to be able to handle both.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Currently kernel memory layout settings are split between "Processor
type and features" and "Platform options" menus. Consolidate them under
"Platform options".
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

CONFIG_ARCH_NO_COHERENT_DMA_MMAP is now functionally identical to
!CONFIG_MMU, so remove the separate symbol.  The only difference is that
arm did not set it for !CONFIG_MMU, but arm uses a separate dma mapping
implementation including its own mmap method, which is handled by moving
the CONFIG_MMU check in dma_can_mmap so that is only applies to the
dma-direct case, just as the other ifdefs for it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	# m68k

Provide a Kconfig choice to select whether only the default ABI, only
call0 ABI or both are supported. The default for XEA2 is windowed, but
it may change for XEA3. Call0 only runs userspace with PS.WOE disabled.
Supporting both windowed and call0 ABIs is tricky, as there's no
indication in the ELF binaries which ABI they use. So it is done by
probing: each process is started with PS.WOE disabled, but the handler
of an illegal instruction exception taken with PS.WOE retries faulting
instruction after enabling PS.WOE. It must happen before any signal is
delivered to the process, otherwise it may be delivered incorrectly.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Allow architectures to opt into ARCH_HAS_BINFMT_FLAT support instead of
assuming that all nommu ports support the format.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: NGreg Ungerer <gerg@linux-m68k.org>

Use CONFIG_MEMMAP_CACHEATTR to initialize MPU as described in the Xtensa
LSP RM document. Coalesce adjacent regions with the same cacheattr.
Update Kconfig help text.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Currently, we have two different implementation of rwsem:

 1) CONFIG_RWSEM_GENERIC_SPINLOCK (rwsem-spinlock.c)
 2) CONFIG_RWSEM_XCHGADD_ALGORITHM (rwsem-xadd.c)

As we are going to use a single generic implementation for rwsem-xadd.c
and no architecture-specific code will be needed, there is no point
in keeping two different implementations of rwsem. In most cases, the
performance of rwsem-spinlock.c will be worse. It also doesn't get all
the performance tuning and optimizations that had been implemented in
rwsem-xadd.c over the years.

For simplication, we are going to remove rwsem-spinlock.c and make all
architectures use a single implementation of rwsem - rwsem-xadd.c.

All references to RWSEM_GENERIC_SPINLOCK and RWSEM_XCHGADD_ALGORITHM
in the code are removed.
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NWaiman Long <longman@redhat.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-um@lists.infradead.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: nios2-dev@lists.rocketboards.org
Cc: openrisc@lists.librecores.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Link: https://lkml.kernel.org/r/20190322143008.21313-3-longman@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

All new 32-bit architectures should have 64-bit userspace off_t type, but
existing architectures has 32-bit ones.

To enforce the rule, new config option is added to arch/Kconfig that defaults
ARCH_32BIT_OFF_T to be disabled for new 32-bit architectures. All existing
32-bit architectures enable it explicitly.

New option affects force_o_largefile() behaviour. Namely, if userspace
off_t is 64-bits long, we have no reason to reject user to open big files.

Note that even if architectures has only 64-bit off_t in the kernel
(arc, c6x, h8300, hexagon, nios2, openrisc, and unicore32),
a libc may use 32-bit off_t, and therefore want to limit the file size
to 4GB unless specified differently in the open flags.
Signed-off-by: NYury Norov <ynorov@caviumnetworks.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NYury Norov <ynorov@marvell.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

The OF_RESERVED_MEM can be used if we have either CMA or the generic
declare coherent code built and we support the early flattened DT.

So don't bother making it a user visible options that is selected
by most configs that fit the above category, but just select it when
the requirements are met.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NRob Herring <robh@kernel.org>

Drop custom spinlock/rwlock code and use ones from asm-generic. This way
there is less code duplication (atomic primitives are reused).
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

When building some xtensa config, I hit the following warning:
  drivers/staging/mt7621-dts/Kconfig:4:warning: 'BUILTIN_DTB' has wrong type.
  'select' only accept arguments of bool and tristate type

It is due to some arch use BUILTIN_DTB as a flag for the need to builtin
dtb but xtensa use it as a string for which dtb to bulltin.
But for this (which dtb to build), it is better to use
BUILTIN_DTB_SOURCE like other arch do.
Signed-off-by: NCorentin Labbe <clabbe@baylibre.com>
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

This patch fix a simple typo.
Signed-off-by: NCorentin Labbe <clabbe@baylibre.com>
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Use 3-byte 'nop' and 'j' instructions that are always present. Don't let
assembler mark a spot right after patchable 'j' instruction as
unreachable and later put literals or padding bytes there. Add separate
implementations of patch_text for SMP and UP cases, avoiding use of
atomics on UP.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Add TIF_SYSCALL_TRACEPOINT flag definition; add _TIF_SYSCALL_TRACEPOINT
to _TIF_WORK_MASK. Call trace_sys_enter from do_syscall_trace_enter and
trace_sys_exit from do_syscall_trace_leave when TIF_SYSCALL_TRACEPOINT
flag is set.
Add declaration of sys_call_table to arch/xtensa/include/asm/syscall.h
Add definition of NR_syscalls to arch/xtensa/include/asm/unistd.h
Select HAVE_SYSCALL_TRACEPOINTS.

This change allows tracing each syscall entry and exit through the
ftrace mechanism.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Implement syscall_get_nr, syscall_rollback, syscall_get_error,
syscall_{get,set}_return_value and syscall_{get,set}_arguments.
Select HAVE_ARCH_TRACEHOOK as Xtensa now has all support for that.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

All architectures except for sparc64 use the dma-direct code in some
form, and even for sparc64 we had the discussion of a direct mapping
mode a while ago.  In preparation for directly calling the direct
mapping code don't bother having it optionally but always build the
code in.  This is a minor hardship for some powerpc and arm configs
that don't pull it in yet (although they should in a relase ot two),
and sparc64 which currently doesn't need it at all, but it will
reduce the ifdef mess we'd otherwise need significantly.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJesper Dangaard Brouer <brouer@redhat.com>
Tested-by: NJesper Dangaard Brouer <brouer@redhat.com>
Tested-by: NTony Luck <tony.luck@intel.com>

These days architectures are mostly out of the business of dealing with
struct scatterlist at all, unless they have architecture specific iommu
drivers.  Replace the ARCH_HAS_SG_CHAIN symbol with a ARCH_NO_SG_CHAIN
one only enabled for architectures with horrible legacy iommu drivers
like alpha and parisc, and conditionally for arm which wants to keep it
disable for legacy platforms.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NPalmer Dabbelt <palmer@sifive.com>

The dma remap code only makes sense for not cache coherent architectures
(or possibly the corner case of highmem CMA allocations) and currently
is only used by arm, arm64, csky and xtensa.  Split it out into a
separate file with a separate Kconfig symbol, which gets the right
copyright notice given that this code was written by Laura Abbott
working for Code Aurora at that point.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NLaura Abbott <labbott@redhat.com>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>

There is nothing architecture specific in the PCMCIA core, so allow
building it everywhere.  The actual host controllers will depend on ISA,
PCI or a specific SOC.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NDominik Brodowski <linux@dominikbrodowski.net>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPaul Burton <paul.burton@mips.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

There is no good reason to duplicate the PCI menu in every architecture.
Instead provide a selectable HAVE_PCI symbol that indicates availability
of PCI support, and a FORCE_PCI symbol to for PCI on and the handle the
rest in drivers/pci.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NPalmer Dabbelt <palmer@sifive.com>
Acked-by: NMax Filippov <jcmvbkbc@gmail.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NPaul Burton <paul.burton@mips.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

All architecures use memblock for early memory management. There is no need
for the CONFIG_HAVE_MEMBLOCK configuration option.

[rppt@linux.vnet.ibm.com: of/fdt: fixup #ifdefs]
  Link: http://lkml.kernel.org/r/20180919103457.GA20545@rapoport-lnx
[rppt@linux.vnet.ibm.com: csky: fixups after bootmem removal]
  Link: http://lkml.kernel.org/r/20180926112744.GC4628@rapoport-lnx
[rppt@linux.vnet.ibm.com: remove stale #else and the code it protects]
  Link: http://lkml.kernel.org/r/1538067825-24835-1-git-send-email-rppt@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1536927045-23536-4-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Tested-by: NJonathan Cameron <jonathan.cameron@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All achitectures select NO_BOOTMEM which essentially becomes 'Y' for any
kernel configuration and therefore it can be removed.

[alexander.h.duyck@linux.intel.com: remove now defunct NO_BOOTMEM from depends list for deferred init]
  Link: http://lkml.kernel.org/r/20180925201814.3576.15105.stgit@localhost.localdomain
Link: http://lkml.kernel.org/r/1536927045-23536-3-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@linux.intel.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ZONE_DMA is intended for magic < 32-bit pools (usually ISA DMA), which
isn't required on xtensa.  Move all the non-highmem memory into
ZONE_NORMAL instead to match other architectures.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

All the cache maintainance is already stubbed out when not enabled,
but merging the two allows us to nicely handle the case where
cache maintainance is required for some devices, but not others.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

A kernel may not need any boot parameters from the bootloader, allow
disabling bootparam parsing in that case.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

If an xtensa core provides an additional IRQ controller it should be
treated as a separate piece of hardware and be driven by an irqchip
driver.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Drop PLATFORM_DEFAULT_MEM_START from the platform/hardware.h headers.
Provide definition of CONFIG_DEFAULT_MEM_START always, allow changing it
only in noMMU configurations when PLATFORM_WANT_DEFAULT_MEM is selected.
Change prompt and description so that it's clear that it controls
PAGE_OFFSET and PHYS_OFFSET.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Now that noMMU cache attributes are set up separately drop no longer
used macro PLATFORM_DEFAULT_MEM_SIZE and config symbol
CONFIG_DEFAULT_MEM_SIZE used for setting it.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Marking default memory region as cached is not always sufficient and is
not flexible. Allow specifying cache attributes for the whole memory
address space with new config entry MEMMAP_CACHEATTR. Apply it after
cache initialization.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Almost all architectures include it.  Add a ARCH_NO_PREEMPT symbol to
disable preempt support for alpha, hexagon, non-coldfire m68k and
user mode Linux.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Move the source of lib/Kconfig.debug and arch/$(ARCH)/Kconfig.debug to
the top-level Kconfig.  For two architectures that means moving their
arch-specific symbols in that menu into a new arch Kconfig.debug file,
and for a few more creating a dummy file so that we can include it
unconditionally.

Also move the actual 'Kernel hacking' menu to lib/Kconfig.debug, where
it belongs.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Instead of duplicating the source statements in every architecture just
do it once in the toplevel Kconfig file.

Note that with this the inclusion of arch/$(SRCARCH/Kconfig moves out of
the top-level Kconfig into arch/Kconfig so that don't violate ordering
constraits while keeping a sensible menu structure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Switch to the generic noncoherent direct mapping implementation.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

HAVE_CC_STACKPROTECTOR should be selected by architectures with stack
canary implementation.  It is not about the compiler support.

For the consistency with commit 050e9baa ("Kbuild: rename
CC_STACKPROTECTOR[_STRONG] config variables"), remove 'CC_' from the
config symbol.

I moved the 'select' lines to keep the alphabetical sorting.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is no arch specific code required for dma-debug, so there is no
need to opt into the support either.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>

This enables KASAN check of the destination buffer.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

Cover kernel addresses above 0x90000000 by the shadow map. Enable
HAVE_ARCH_KASAN when MMU is enabled. Provide kasan_early_init that fills
shadow map with writable copies of kasan_zero_page. Call
kasan_early_init right after mmu initialization in the setup_arch.
Provide kasan_init that allocates proper shadow map pages from the
memblock and puts these pages into the shadow map for addresses from
VMALLOC area to the end of KSEG. Call kasan_init right after memblock
initialization. Don't use KASAN for the boot code, MMU and KASAN
initialization and page fault handler. Make kernel stack size 4 times
larger when KASAN is enabled to avoid stack overflows.
GCC 7.3, 8 or newer is required to build the xtensa kernel with KASAN.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>

The implementation is adopted from the ARM arch. GCC 7.3, 8 or newer is
required for building the xtensa kernel with SSP.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>