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33 Commits (ca5788aba3e8153da38cf99ca3ce2294f032fb51)

Author SHA1 Message Date
Greentime Hu 987553894f nds32: fix build error "relocation truncated to fit: R_NDS32_25_PCREL_RELA" when
make allyesconfig

It will cause a linking error because the jump assembly code were using j,
however it may be not enough to jump to the destination. We have to change it
with pseudo instruction b. In that way, assembler will generate a set of safe
assembly codes to make sure the destination is able to jump.

Toolchain:
https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/8.1.0/x86_64-gcc-8.1.0-nolibc-nds32le-linux.tar.gz

Command:
PATH=/NOBACKUP/atcsqa06/greentime/os/toolchain-kernel.org/gcc-8.1.0-nolibc/nds32le-linux/bin:$PATH ARCH=nds32 CROSS_COMPILE=nds32le-linux- make allyesconfig
PATH=/NOBACKUP/atcsqa06/greentime/os/toolchain-kernel.org/gcc-8.1.0-nolibc/nds32le-linux/bin:$PATH ARCH=nds32 CROSS_COMPILE=nds32le-linux- make -j8

  MODPOST vmlinux.o
WARNING: EXPORT symbol "copy_page" [vmlinux] version generation failed, symbol will not be versioned.
WARNING: EXPORT symbol "clear_page" [vmlinux] version generation failed, symbol will not be versioned.
nds32le-linux-ld: kernel/futex.o:(.fixup+0x4): relocation truncated to fit: R_NDS32_25_PCREL_RELA against `.text'
nds32le-linux-ld: kernel/futex.o:(.fixup+0xaa): relocation truncated to fit: R_NDS32_25_PCREL_RELA against `.text'
nds32le-linux-ld: kernel/futex.o:(.fixup+0xb0): relocation truncated to fit: R_NDS32_25_PCREL_RELA against `.text'
nds32le-linux-ld: kernel/futex.o:(.fixup+0xb6): relocation truncated to fit: R_NDS32_25_PCREL_RELA against `.text'
nds32le-linux-ld: kernel/futex.o:(.fixup+0xbc): relocation truncated to fit: R_NDS32_25_PCREL_RELA against `.text'
nds32le-linux-ld: kernel/futex.o:(.fixup+0xc4): relocation truncated to fit: R_NDS32_25_PCREL_RELA against `.text'
Makefile:1010: recipe for target 'vmlinux' failed
make: *** [vmlinux] Error 1

Signed-off-by: Greentime Hu <greentime@andestech.com>
2018-07-05 16:13:47 +08:00
Greentime Hu f706abf188 nds32: To implement these icache invalidation APIs since nds32 cores don't snoop
data cache.
This issue is found by Guo Ren. Based on the Documentation/core-api/cachetlb.rst
and it says:

"Any necessary cache flushing or other coherency operations
that need to occur should happen here.  If the processor's
instruction cache does not snoop cpu stores, it is very
likely that you will need to flush the instruction cache
for copy_to_user_page()."

"If the icache does not snoop stores then this
routine(flush_icache_range) will need to flush it."

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
2018-07-03 11:11:56 +08:00
Linus Torvalds 0bbcce5d1e Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timers and timekeeping updates from Thomas Gleixner:

 - Core infrastucture work for Y2038 to address the COMPAT interfaces:

     + Add a new Y2038 safe __kernel_timespec and use it in the core
       code

     + Introduce config switches which allow to control the various
       compat mechanisms

     + Use the new config switch in the posix timer code to control the
       32bit compat syscall implementation.

 - Prevent bogus selection of CPU local clocksources which causes an
   endless reselection loop

 - Remove the extra kthread in the clocksource code which has no value
   and just adds another level of indirection

 - The usual bunch of trivial updates, cleanups and fixlets all over the
   place

 - More SPDX conversions

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  clocksource/drivers/mxs_timer: Switch to SPDX identifier
  clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier
  clocksource/drivers/timer-imx-gpt: Switch to SPDX identifier
  clocksource/drivers/timer-imx-gpt: Remove outdated file path
  clocksource/drivers/arc_timer: Add comments about locking while read GFRC
  clocksource/drivers/mips-gic-timer: Add pr_fmt and reword pr_* messages
  clocksource/drivers/sprd: Fix Kconfig dependency
  clocksource: Move inline keyword to the beginning of function declarations
  timer_list: Remove unused function pointer typedef
  timers: Adjust a kernel-doc comment
  tick: Prefer a lower rating device only if it's CPU local device
  clocksource: Remove kthread
  time: Change nanosleep to safe __kernel_* types
  time: Change types to new y2038 safe __kernel_* types
  time: Fix get_timespec64() for y2038 safe compat interfaces
  time: Add new y2038 safe __kernel_timespec
  posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME
  time: Introduce CONFIG_COMPAT_32BIT_TIME
  time: Introduce CONFIG_64BIT_TIME in architectures
  compat: Enable compat_get/put_timespec64 always
  ...
2018-06-04 20:27:54 -07:00
Linus Torvalds e5a594643a dma-mapping updates for 4.18:
- replaceme the force_dma flag with a dma_configure bus method.
    (Nipun Gupta, although one patch is Ñ–ncorrectly attributed to me
     due to a git rebase bug)
  - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)
  - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
    right thing for bounce buffering.
  - move dma-debug initialization to common code, and apply a few cleanups
    to the dma-debug code.
  - cleanup the Kconfig mess around swiotlb selection
  - swiotlb comment fixup (Yisheng Xie)
  - a trivial swiotlb fix. (Dan Carpenter)
  - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)
  - add a new generic dma-noncoherent dma_map_ops implementation and use
    it for arc, c6x and nds32.
  - improve scatterlist validity checking in dma-debug. (Robin Murphy)
  - add a struct device quirk to limit the dma-mask to 32-bit due to
    bridge/system issues, and switch x86 to use it instead of a local
    hack for VIA bridges.
  - handle devices without a dma_mask more gracefully in the dma-direct
    code.
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Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - replace the force_dma flag with a dma_configure bus method. (Nipun
   Gupta, although one patch is Ñ–ncorrectly attributed to me due to a
   git rebase bug)

 - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)

 - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
   right thing for bounce buffering.

 - move dma-debug initialization to common code, and apply a few
   cleanups to the dma-debug code.

 - cleanup the Kconfig mess around swiotlb selection

 - swiotlb comment fixup (Yisheng Xie)

 - a trivial swiotlb fix. (Dan Carpenter)

 - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)

 - add a new generic dma-noncoherent dma_map_ops implementation and use
   it for arc, c6x and nds32.

 - improve scatterlist validity checking in dma-debug. (Robin Murphy)

 - add a struct device quirk to limit the dma-mask to 32-bit due to
   bridge/system issues, and switch x86 to use it instead of a local
   hack for VIA bridges.

 - handle devices without a dma_mask more gracefully in the dma-direct
   code.

* tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits)
  dma-direct: don't crash on device without dma_mask
  nds32: use generic dma_noncoherent_ops
  nds32: implement the unmap_sg DMA operation
  nds32: consolidate DMA cache maintainance routines
  x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag
  x86/pci-dma: remove the explicit nodac and allowdac option
  x86/pci-dma: remove the experimental forcesac boot option
  Documentation/x86: remove a stray reference to pci-nommu.c
  core, dma-direct: add a flag 32-bit dma limits
  dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs
  dma-debug: check scatterlist segments
  c6x: use generic dma_noncoherent_ops
  arc: use generic dma_noncoherent_ops
  arc: fix arc_dma_{map,unmap}_page
  arc: fix arc_dma_sync_sg_for_{cpu,device}
  arc: simplify arc_dma_sync_single_for_{cpu,device}
  dma-mapping: provide a generic dma-noncoherent implementation
  dma-mapping: simplify Kconfig dependencies
  riscv: add swiotlb support
  riscv: only enable ZONE_DMA32 for 64-bit
  ...
2018-06-04 10:58:12 -07:00
Christoph Hellwig 267d2e18a2 nds32: use generic dma_noncoherent_ops
Switch to the generic noncoherent direct mapping implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Greentime Hu <greentime@andestech.com>
Tested-by: Greentime Hu <greentime@andestech.com>
2018-05-29 16:10:32 +02:00
Greentime Hu abb90a24ea nds32: To fix a cache inconsistency issue by setting correct cacheability of NTC
The nds32 architecture will use physical memory when interrupt or
exception comes and it will use the setting of NTC0-4. The original
implementation didn't consider the DRAM start address may start from 1GB,
2GB or 3GB to cause this issue. It will write the data to DRAM if it is
running in physical address however kernel will read the data with
virtaul address through data cache. In this case, the data of DRAM is
latest.

This fix will set the correct cacheability to let kernel write/read the
latest data in cache instead of DRAM.

Signed-off-by: Greentime Hu <greentime@andestech.com>
2018-05-23 13:26:22 +08:00
Greentime Hu 8769c22349 nds32: To refine readability of INT_MASK_INITAIAL_VAL
Refine readability of INT_MASK_INITAIAL_VAL with meaningful macro instead
of magic number.

Signed-off-by: Greentime Hu <greentime@andestech.com>
2018-05-23 13:26:21 +08:00
Greentime Hu bb912671e3 nds32: Fix the unknown type u8 issue.
It broke the 'allmodconfig' build.
We need to include <linux/types.h> to make sure the type is defined
before using it.

Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-05-23 13:26:21 +08:00
Greentime Hu e3f4624388 nds32: Fix the symbols undefined issue by exporting them.
It broke the 'allmodconfig' build.
  LD      vmlinux
  SYSMAP  System.map
  Building modules, stage 2.
  MODPOST 5028 modules
ERROR: "flush_dcache_page" [net/sunrpc/xprtrdma/rpcrdma.ko] undefined!
ERROR: "empty_zero_page" [net/ceph/libceph.ko] undefined!
ERROR: "save_stack_trace" [kernel/backtracetest.ko] undefined!
ERROR: "clear_page" [fs/ocfs2/dlm/ocfs2_dlm.ko] undefined!
ERROR: "copy_page" [fs/nilfs2/nilfs2.ko] undefined!
...

Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-05-23 13:26:20 +08:00
Greentime Hu 03969d0b3a nds32: Fix xfs_buf built failed by export invalidate_kernel_vmap_range and flush_kernel_vmap_range
It broke the 'allmodconfig' build.
fs/xfs/xfs_buf.c: In function 'xfs_buf_bio_end_io':
fs/xfs/xfs_buf.c:1242:3: error: implicit declaration of function 'invalidate_kernel_vmap_range' [-Werror=implicit-function-declaration]
   invalidate_kernel_vmap_range(bp->b_addr, xfs_buf_vmap_len(bp));
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/xfs/xfs_buf.c: In function 'xfs_buf_ioapply_map':
fs/xfs/xfs_buf.c:1312:4: error: implicit declaration of function 'flush_kernel_vmap_range' [-Werror=implicit-function-declaration]
    flush_kernel_vmap_range(bp->b_addr,
    ^~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-05-23 13:26:20 +08:00
Greentime Hu 8cedb78fdf nds32: Fix drivers/gpu/drm/udl/udl_fb.c building error by defining PAGE_SHARED
It broke the 'allmodconfig' build.
drivers/gpu/drm/udl/udl_fb.c: In function 'udl_fb_mmap':
drivers/gpu/drm/udl/udl_fb.c:183:52: error: 'PAGE_SHARED' undeclared (first use in this function)
   if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))
                                                    ^~~~~~~~~~~
drivers/gpu/drm/udl/udl_fb.c:183:52: note: each undeclared identifier is reported only once for each function it appears in
make[4]: *** [drivers/gpu/drm/udl/udl_fb.o] Error 1

Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-05-23 13:26:20 +08:00
Greentime Hu 81560e011a nds32: Fix building error of crypto/xor.c by adding xor.h
When I compiled with allmodconfig, it caused this building failed.
crypto/xor.c:25:21: fatal error: asm/xor.h: No such file or directory
 #include <asm/xor.h>
                     ^
compilation terminated.

Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-05-23 13:26:20 +08:00
Arnd Bergmann 2b5a9a37e9 time: Add an asm-generic/compat.h file
We have a couple of files that try to include asm/compat.h on
architectures where this is available. Those should generally use the
higher-level linux/compat.h file, but that in turn fails to include
asm/compat.h when CONFIG_COMPAT is disabled, unless we can provide
that header on all architectures.

This adds the asm/compat.h for all remaining architectures to
simplify the dependencies.

Architectures that are getting removed in linux-4.17 are not changed
here, to avoid needless conflicts with the removal patches. Those
architectures are broken by this patch, but we have already shown
that they have no users.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-04-19 13:28:51 +02:00
Matthew Wilcox b93b016313 page cache: use xa_lock
Remove the address_space ->tree_lock and use the xa_lock newly added to
the radix_tree_root.  Rename the address_space ->page_tree to ->i_pages,
since we don't really care that it's a tree.

[willy@infradead.org: fix nds32, fs/dax.c]
  Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:39 -07:00
Greentime Hu e71ea3bada nds32: Build infrastructure
This patch adds Makefile, Kconfig and vmlinux.lds.S files required for building
an nds32 kernel.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:35 +08:00
Greentime Hu 5c86fa7f7f nds32: Miscellaneous header files
This patch introduces some miscellaneous header files.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:34 +08:00
Greentime Hu c9a4a8da6b nds32: Loadable modules
This patch adds support for loadable modules.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by:  Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:34 +08:00
Greentime Hu 3af6e29254 nds32: L2 cache support
This patch adds L2 cache support.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:34 +08:00
Greentime Hu e9d0704aa1 nds32: Debugging support
This patch adds ptrace support.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:34 +08:00
Greentime Hu ace02e2bad nds32: Library functions
This patch add support for various library functions.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:33 +08:00
Greentime Hu 7ecbac743a nds32: Signal handling support
This patch adds support for signal handling.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
2018-02-22 10:44:33 +08:00
Greentime Hu eefacd1dfe nds32: VDSO support
This patch adds VDSO support. The VDSO code is currently used for
sys_rt_sigreturn() and optimised gettimeofday() (using the SoC timer counter).

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:33 +08:00
Greentime Hu 1932fbe36e nds32: System calls handling
This patch adds support for system calls.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:33 +08:00
Greentime Hu 3172c605eb nds32: ELF definitions
This patch adds definitions for the ELF format, relocation types, vdso
locations and EXEC_PAGESIZE.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:33 +08:00
Greentime Hu 80081b3391 nds32: DMA mapping API
This patch adds support for the DMA mapping API. It uses dma_map_ops for
flexibility.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:32 +08:00
Greentime Hu 4a64f68dbd nds32: Device specific operations
This patch introduces ioremap implementations.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:32 +08:00
Greentime Hu 484367b6a9 nds32: Atomic operations
This patch includes the atomic and futex operations. Many atomic operations use
the load-lock word(llw) and store-condition word(scw) operations.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:32 +08:00
Greentime Hu f13c34b906 nds32: IRQ handling
This patch includes irq related functions and irqchip_init().

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:32 +08:00
Greentime Hu a15e9ffa87 nds32: Process management
This patch includes copy_thread(), start_thread() implementation and cpu_context
structure definition. nds32 uses $r25 to get current task_struct.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:32 +08:00
Greentime Hu 7de9cf4740 nds32: Cache and TLB routines
This patch contains cache and TLB maintenance functions.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:32 +08:00
Greentime Hu 2e1aecb970 nds32: MMU definitions
This patch includes virtual memory layout, PHYS_OFFSET is defined as 0x0. It
also includes the 4KB/8KB page size configurations and pte operations.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:31 +08:00
Greentime Hu 2923f5ea77 nds32: Exception handling
This patch includes the exception/interrupt entries, pt_reg structure and
related accessors.

/* Unaligned accessing handling*/
Andes processors cannot load/store information which is not naturally
aligned on the bus, i.e., loading a 4 byte data whose start address must
be divisible by 4. If unaligned data accessing is happened, data
unaligned exception will be triggered and user will get SIGSEGV or
kernel oops according to the unaligned address. In order to make user be
able to load/store data from an unaligned address, software load/store
emulation is implemented in arch/nds32/mm/alignment.c to address data
unaligned exception.

Unaligned accessing handling is disabled by default because it is not a
normal case. User can enable this feature by following steps.

A. Compile time:
    1. Enable kernel config CONFIG_ALIGNMENT_TRAP
B. Run time:
    1. Enter /proc/sys/nds32/unaligned_acess folder
    2. Write 1 to file enable_mode to enable unaligned accessing
       handling. User can disable it by writing 0 to this file.
    3. Write 1 to file debug to show which unaligned address is under
       processing. User can disable it by writing 0 to this file.

However, unaligned accessing handler cannot work if this unaligned
address is not accessible such as protection violation. On this
condition, the default behaviors for addressing data unaligned exception
still happen

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:31 +08:00
Greentime Hu e1d82de681 nds32: Assembly macros and definitions
This patch includes assembly macros, bit field definitions used in .S
files across arch/nds32/.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2018-02-22 10:44:31 +08:00