MIPS: Add basic support for ptrace single step

In the current code, arch_has_single_step() is not defined on MIPS,
that means MIPS does not support instruction single-step for user mode.

Delve is a debugger for the Go programming language, the ptrace syscall
PtraceSingleStep() failed [1] on MIPS and then the single step function
can not work well, we can see that PtraceSingleStep() definition returns
ptrace(PTRACE_SINGLESTEP) [2].

So it is necessary to support ptrace single step on MIPS.

At the beginning, we try to use the Debug Single Step exception on the
Loongson 3A4000 platform, but it has no effect when set CP0_DEBUG SSt
bit, this is because CP0_DEBUG NoSSt bit is 1 which indicates no
single-step feature available [3], so this way which is dependent on the
hardware is almost impossible.

With further research, we find out there exists a common way used with
break instruction in arch/alpha/kernel/ptrace.c, it is workable.

For the above analysis, define arch_has_single_step(), add the common
function user_enable_single_step() and user_disable_single_step(), set
flag TIF_SINGLESTEP for child process, use break instruction to set
breakpoint.

We can use the following testcase to test it:
tools/testing/selftests/breakpoints/step_after_suspend_test.c

 $ make -C tools/testing/selftests TARGETS=breakpoints
 $ cd tools/testing/selftests/breakpoints

Without this patch:

 $ ./step_after_suspend_test -n
 TAP version 13
 1..4
 # ptrace(PTRACE_SINGLESTEP) not supported on this architecture: Input/output error
 ok 1 # SKIP CPU 0
 # ptrace(PTRACE_SINGLESTEP) not supported on this architecture: Input/output error
 ok 2 # SKIP CPU 1
 # ptrace(PTRACE_SINGLESTEP) not supported on this architecture: Input/output error
 ok 3 # SKIP CPU 2
 # ptrace(PTRACE_SINGLESTEP) not supported on this architecture: Input/output error
 ok 4 # SKIP CPU 3
 # Totals: pass:0 fail:0 xfail:0 xpass:0 skip:4 error:0

With this patch:

 $ ./step_after_suspend_test -n
 TAP version 13
 1..4
 ok 1 CPU 0
 ok 2 CPU 1
 ok 3 CPU 2
 ok 4 CPU 3
 # Totals: pass:4 fail:0 xfail:0 xpass:0 skip:0 error:0

[1] https://github.com/go-delve/delve/blob/master/pkg/proc/native/threads_linux.go#L50
[2] https://github.com/go-delve/delve/blob/master/vendor/golang.org/x/sys/unix/syscall_linux.go#L1573
[3] http://www.t-es-t.hu/download/mips/md00047f.pdf

Reported-by: Guoqi Chen <chenguoqi@loongson.cn>
Signed-off-by: Xingxing Su <suxingxing@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MAINTAINERS: replace non-matching patterns for loongson{2,3}

Commit ffe1f9356fbe ("MAINTAINERS: Add Loongson-2/Loongson-3 maintainers")
adds quite generic file entries for drivers/*/*loongson{2,3}* and
drivers/*/*/*loongson{2,3}* to be informed on changes to all loongson{2,3}
files in drivers.

However, only the pattern 'drivers/*/*loongson2*' matches to one file in
the repository, i.e., drivers/cpufreq/loongson2_cpufreq.c; all other
patterns have no file matches.

Hence, ./scripts/get_maintainer.pl --self-test=patterns complains:

  warning: no file matches    F:    drivers/*/*/*loongson2*
  warning: no file matches    F:    drivers/*/*/*loongson3*
  warning: no file matches    F:    drivers/*/*loongson3*

As in the last two and half years, no further files and drivers have
showed up to match those patterns, just name the one file that matches
explicitly and delete the others without a match.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Make check condition for SDBBP consistent with EJTAG spec

According to MIPS EJTAG Specification [1], a Debug Breakpoint
exception occurs when an SDBBP instruction is executed, the
CP0_DEBUG bit DBp indicates that a Debug Breakpoint exception
occurred.

When I read the original code, it looks a little confusing
at first glance, just check bit DBp for SDBBP to make the
code more readable, it will be much easier to understand.

[1] http://www.t-es-t.hu/download/mips/md00047f.pdf

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

mips: Replace lkml.org links with lore

As started by commit 05a5f51ca566 ("Documentation: Replace lkml.org
links with lore"), replace lkml.org links with lore to better use a
single source that's more likely to stay available long-term.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Revert "MIPS: microMIPS: Fix the judgment of mm_jr16_op and mm_jalr_op"

This reverts commit 9308579fef3ddde19da9d45e23bf36d41932417f.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: crash_dump.c: Simplify copy_oldmem_page()

Replace kmap_atomic_pfn() with kmap_local_pfn() which is preemptible and
can take page faults.

Remove the indirection of the dump page and the related cruft which is not
longer required.

Remove unused or redundant header files.

Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Revert "mips: Manually call fdt_init_reserved_mem() method"

This reverts commit 3751cbda8f223549d7ea28803cbec8ac87e43ed2.

Originally the patch was created to fix the reserved-memory DT-node
parsing failure on the early stages of the platform memory initialization.
That happened due to the two early memory allocators utilization that
time: bootmem and memblock. At first the platform-specific memory mapping
array was initialized. Then the early_init_fdt_scan_reserved_mem() was
called, which couldn't fully parse the "reserved-memory" DT-node since
neither memblock nor bootmem allocators hadn't been initialized at that
stage, so the fdt_init_reserved_mem() method failed on the memory
allocation calls. Only after that the platform-specific memory mapping
were used to create proper bootmem and memblock structures and let the
early memory allocations work.  That's why we had to call the
fdt_init_reserved_mem() method one more time to retry the initialization
of the features like CMA.

The necessity to have that fix was disappeared after the full memblock
support had been added to the MIPS kernel and all plat_mem_setup() had
been fixed to add the memory regions right into the memblock memory pool.
Let's revert that patch then especially after having Paul reported that
the second fdt_init_reserved_mem() call causes the reserved memory pool
being created twice bigger than implied.

Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map")
Reported-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: process: Fix no previous prototype warning

unwind_stack_by_address and unwind_stack need <asm/stacktrace.h>.
arch_align_stack needs <asm/exec.h>

link: https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org/thread/ZPL2RRA6RZKRQZI5IGOVLFXN2GVZBN3L/
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: compressed: fix build with enabled UBSAN

Commit 1e35918ad9d1 ("MIPS: Enable Undefined Behavior Sanitizer
UBSAN") added a possibility to build the entire kernel with UBSAN
instrumentation for MIPS, with the exception for VDSO.
However, self-extracting head wasn't been added to exceptions, so
this occurs:

mips-alpine-linux-musl-ld: arch/mips/boot/compressed/decompress.o:
in function `FSE_buildDTable_wksp':
decompress.c:(.text.FSE_buildDTable_wksp+0x278): undefined reference
to `__ubsan_handle_shift_out_of_bounds'
mips-alpine-linux-musl-ld: decompress.c:(.text.FSE_buildDTable_wksp+0x2a8):
undefined reference to `__ubsan_handle_shift_out_of_bounds'
mips-alpine-linux-musl-ld: decompress.c:(.text.FSE_buildDTable_wksp+0x2c4):
undefined reference to `__ubsan_handle_shift_out_of_bounds'
mips-alpine-linux-musl-ld: arch/mips/boot/compressed/decompress.o:
decompress.c:(.text.FSE_buildDTable_raw+0x9c): more undefined references
to `__ubsan_handle_shift_out_of_bounds' follow

Add UBSAN_SANITIZE := n to mips/boot/compressed/Makefile to exclude
it from instrumentation scope and fix this issue.

Fixes: 1e35918ad9d1 ("MIPS: Enable Undefined Behavior Sanitizer UBSAN")
Cc: stable@vger.kernel.org # 5.0+
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: relocatable: Use __kaslr_offset in show_kernel_relocation

The type of the VMLINUX_LOAD_ADDRESS macro is the (unsigned long long)
in 32bits kernel but (unsigned long) in the 64-bit kernel. Although there
is no error here, avoid using it to calculate kaslr_offset.

Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: relocatable: Provide kaslr_offset() to get the kernel offset

Provide kaslr_offset() to get the kernel offset when KASLR is enabled.
Error may occur before update_kaslr_offset(), so put it at the end of
the offset branch.

Fixes: a307a4ce9ecd ("MIPS: Loongson64: Add KASLR support")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: kernel: Support extracting off-line stack traces from user-space with perf

Add perf_event_mips_regs/perf_reg_value/perf_reg_validate to support
features HAVE_PERF_REGS/HAVE_PERF_USER_STACK_DUMP in kernel.

[ayan@wavecomp.com: Repick this patch for unwinding userstack backtrace
 by perf and libunwind on MIPS based CPU.]

[ralf@linux-mips.org: Add perf_get_regs_user() which is required after
'commit 88a7c26af8da ("perf: Move task_pt_regs sampling into arch code")'.]

[yangtiezhu@loongson.cn: Fix build error about perf_get_regs_user() after
commit 76a4efa80900 ("perf/arch: Remove perf_sample_data::regs_user_copy"),
and also separate the original patches into two parts (MIPS kernel and perf
tools) to merge easily.]

The original patches:
https://lore.kernel.org/patchwork/patch/1126521/
https://lore.kernel.org/patchwork/patch/1126520/

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Archer Yan <ayan@wavecomp.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: pistachio: remove obsolete include/asm/mach-pistachio

Since commit 02bd530f888c ("MIPS: generic: Increase NR_IRQS to 256")
include/asm/mach-pistachio/irq.h just does nothing.
Remove the file along with mach-pistachio folder and include compiler
directive.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

mips: dts: Add support for Cisco SG220-26 switch

Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

dt-bindings: Add Cisco prefix to vendor list

Signed-off-by: Bert Vermeulen <bert@biot.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Add Realtek RTL838x/RTL839x support as generic MIPS system

This is just enough system to boot the kernel with earlycon working.

Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Sander Vanheule <sander@svanheule.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Add support for Realtek RTL838x/RTL839x switch SoCs

The RTL838x/839x family of SoCs are Realtek switches with an embedded
MIPS core.

* RTL838x - 500MHz 4kce single core - 1Gbit ports and L2 features
* RTL839x - 700MHz 34Kc single core - 1Gbit ports and L2 features

These switches, depending on the exact part number, will have anywhere
between 8 and 52 ports. The MIPS core is wired to a switch cpu port which
has a tagging feature allowing us to make use of the DSA subsystem.
The SoCs are somewhat basic in certain areas, getting better with more
advanced features on newer series.

The switch functionality is MMIO-mapped via a large MFD region.

The SoCs have the following peripherals
* ethernet
* switch
* uart - ns16550a
* spi-flash interface
* gpio
* wdt
* led

The code was derived from various vendor SDKs based on Linux v2.6
kernels.

This patchset allows us to boot RTL838x/RTL839x units with basic support.
Most of the other drivers are already written and functional, and work to
get them upstream is already in progress.

Signed-off-by: Birger Koblitz <mail@birger-koblitz.de>
Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Sander Vanheule <sander@svanheule.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

dt-bindings: mips: Add support for RTL83xx SoC series

Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: ralink: manage low reset lines

Reset lines with indices smaller than 8 are currently considered invalid
by the rt2880-reset reset controller.

The MT7621 SoC uses a number of these low reset lines. The DTS defines
reset lines "hsdma", "fe", and "mcm" with respective values 5, 6, and 2.
As a result of the above restriction, these resets cannot be asserted or
de-asserted by the reset controller. In cases where the bootloader does
not de-assert these lines, this results in e.g. the MT7621's internal
switch staying in reset.

Change the reset controller to only ignore the system reset, so all
reset lines with index greater than 0 are considered valid.

Signed-off-by: Sander Vanheule <sander@svanheule.net>
Acked-by: John Crispin <john@phrozen.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: of: Introduce helper function to get DTB

Selection of the DTB to be used was burried in more or less readable
code in head.S. Move this code into a inline helper function and
use it.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>

arch: mips: kernel: Fix two spelling in smp.c

s/logcal/logical/
s/intercpu/inter-CPU/

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: malta-time: remove unneeded semicolon

Eliminate the following coccicheck warning:
./arch/mips/mti-malta/malta-time.c:141:2-3: Unneeded semicolon

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

KVM: MIPS: remove unneeded semicolon

Eliminate the following coccicheck warning:
./arch/mips/kvm/mips.c:151:2-3: Unneeded semicolon

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: fix kernel_stack_pointer()

MIPS always save kernel stack pointer in regs[29]

Signed-off-by: Huang Pei <huangpei@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Fix inline asm input/output type mismatch in checksum.h used with Clang

Fix the following build error when make M=samples/bpf used with Clang:

  CLANG-bpf  samples/bpf/sockex2_kern.o
In file included from samples/bpf/sockex2_kern.c:7:
In file included from ./include/uapi/linux/if_tunnel.h:7:
In file included from ./include/linux/ip.h:16:
In file included from ./include/linux/skbuff.h:28:
In file included from ./include/net/checksum.h:22:
./arch/mips/include/asm/checksum.h:161:9: error: unsupported inline asm: input with type 'unsigned long' matching output with type '__wsum' (aka 'unsigned int')
        : "0" ((__force unsigned long)daddr),
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

This is a known issue on MIPS [1], the changed code can be compiled
successfully by both GCC and Clang.

[1] https://lore.kernel.org/linux-mips/CAG_fn=W0JHf8QyUX==+rQMp8PoULHrsQCa9Htffws31ga8k-iw@mail.gmail.com/

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: mm:remove function __uncached_access()

MIPS can now use the default uncached_access like other archs.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: loongson2ef: remove function __uncached_access()

We no longer need the MESA workaround, so remove it.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: asm: spram: remove unneeded semicolon

Remove a superfluous semicolon after function definition.

Signed-off-by: Chengyang Fan <cy.fan@huawei.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: vpe: Remove vpe_getcwd

I couldn't find any user of the dubious vpe_getcwd so far. So remove it and
get rid of another set_fs(KERNEL_DS).

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

mips: cacheinfo: Remove unnecessary increment of level

kernel test robot throws below warning ->

arch/mips/kernel/cacheinfo.c:112:3: warning: Variable 'level' is
modified but its new value is never used. [unreadVariable]

Remove unnecessary increment of level at the end.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Add is_jr_ra_ins() to end the loop early

For those leaf functions, they are likely to have no stack operations.
Add is_jr_ra_ins() to determine whether jr ra has been touched before
the frame_size is found. Without this patch, the get frame_size operation
may be out of range and get the frame_size from the next nested function.

There is no POOL32A format in uapi/asm/inst.h, so some bits here use the
format of r_format instead.
e.g.
---------------------------------------------------------------------
|    format      |  31:26  | 25:21 | 20:16 |    15:6    |    5:0    |
-----------------+---------+-------+-------+------------+------------
| pool32a_format | pool32a |  rt   |  rs   |   jalrc    | pool32axf |
-----------------+---------+-------+-------+------------+------------
|    r_format    |  opcode |  rs   |  rt   | rd:5, re:5 |    func   |
---------------------------------------------------------------------

Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Fix get_frame_info() handing of function size

[1]: Commit b6c7a324df37b ("MIPS: Fix get_frame_info() handling of
                            microMIPS function size")
[2]: Commit 2b424cfc69728 ("MIPS: Remove function size check in
                            get_frame_info()")

First patch added a constant to check the number of iterations against.
Second patch fixed the situation that info->func_size is zero.

However, func_size member became useless after the second commit. Without
ip_end, the get frame_size operation may be out of range although KALLSYMS
enabled. Thus, check func_size first. Then make ip_end be the sum of ip
and a constant (512) if func_size is equal to 0. Otherwise make ip_end be
the sum of ip and func_size.

Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: microMIPS: Fix the judgment of mm_jr16_op and mm_jalr_op

mm16_r5_format.rt is 5 bits, so directly judge the value if equal or not.
mm_jalr_op requires 7th to 16th bits. These 10 which bits generated by
shifting u_format.uimmediate by 6 may be affected by sign extension.
Thus, take out the 10 bits for comparison.

Without this patch, errors may occur, such as these bits are all ones.

Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: process: Remove unnecessary headers inclusion

Some headers are not necessary, remove them and sort includes.

Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MAINTAINERS: Update my e-mail address throughout

I find linux-mips.org too unreliable to rely on, so move to a place
I have proper control over.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

sound: Add n64 driver

This adds support for the Nintendo 64 console's sound.

Signed-off-by: Lauri Kasanen <cand@gmx.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: make kgdb depend on FPU support

kgdb fails to build when the FPU support is disabled:

arch/mips/kernel/kgdb.c: In function 'dbg_set_reg':
arch/mips/kernel/kgdb.c:147:35: error: 'struct thread_struct' has no member named 'fpu'
  147 |    memcpy((void *)&current->thread.fpu.fcr31, mem,
      |                                   ^
arch/mips/kernel/kgdb.c:155:34: error: 'struct thread_struct' has no member named 'fpu'
  155 |   memcpy((void *)&current->thread.fpu.fpr[fp_reg], mem,

This is only relevant for CONFIG_EXPERT=y, so disallowing it
in Kconfig is an easier workaround than fixing it properly.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: jazz: always allow little-endian builds

The kernel test robot keeps reporting the same bug when it
shows up in new files after random unrelated patches:

In file included from arch/mips/include/uapi/asm/byteorder.h:13,
                 from arch/mips/include/asm/bitops.h:20,
                 from include/linux/bitops.h:26,
                 from include/linux/kernel.h:12,
                 from include/linux/clk.h:13,
                 from drivers/base/regmap/regmap-mmio.c:7:
include/linux/byteorder/big_endian.h:8:2: warning: #warning inconsistent configuration, needs CONFIG_CPU_BIG_ENDIAN [-Wcpp]
    8 | #warning inconsistent configuration, needs CONFIG_CPU_BIG_ENDIAN
      |  ^~~~~~~
drivers/base/regmap/regmap-mmio.c: In function 'regmap_mmio_gen_context':
>> drivers/base/regmap/regmap-mmio.c:274:2: error: duplicate case value
  274 |  case REGMAP_ENDIAN_NATIVE:
      |  ^~~~
drivers/base/regmap/regmap-mmio.c:246:2: note: previously used here
  246 |  case REGMAP_ENDIAN_NATIVE:

The problem is that some randconfig builds end up on the MIPS jazz
platform with neither CONFIG_CPU_BIG_ENDIAN nor CONFIG_CPU_LITTLE_ENDIAN
because no specific machine is selected. As it turns out, all jazz
machines support little-endian kernels, so this can simply be allowed
globally.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Make definitions of MIPSInst_FMA_{FUNC,FMTM} consistent with MIPS64 manual

The kernel definitions of MIPSInst_FMA_FUNC and MIPSInst_FMA_FFMT are not
consistent with MADD.fmt, NMADD.fmt and NMSUB.fmt in the MIPS64 manual [1],
the field func is bit 5..3 and fmt is bit 2..0, fix them. Otherwise there
exists error when add new instruction simulation.

[1] https://www.mips.com/?do-download=the-mips64-instruction-set-v6-06

Reported-by: Ming Wang <wangming01@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

mips: Add N64 machine type

Add support for the Nintendo 64.

Signed-off-by: Lauri Kasanen <cand@gmx.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Revert "MIPS: Remove unused R4300 CPU support"

This reverts commit f9065b54d437c4660e3d974ad9ce5188c068cd76.

We're adding Nintendo 64 support, so the VR4300 is no longer unused.

Signed-off-by: Lauri Kasanen <cand@gmx.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: mm: Add prototype for function __update_cache

This commit adds a prototype to fix error at W=1:

arch/mips/mm/cache.c:129:6: error: no previous prototype
for '__update_cache' [-Werror=missing-prototypes]

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: mm: abort uaccess retries upon fatal signal

When there's a fatal signal pending, MIPS's do_page_fault()
implementation returns. The intent is that we'll return to the
faulting userspace instruction, delivering the signal on the way.

However, if we take a fatal signal during fixing up a uaccess, this
results in a return to the faulting kernel instruction, which will be
instantly retried, resulting in the same fault being taken forever. As
the task never reaches userspace, the signal is not delivered, and the
task is left unkillable. While the task is stuck in this state, it can
inhibit the forward progress of the system.

To avoid this, we must ensure that when a fatal signal is pending, we
apply any necessary fixup for a faulting kernel instruction. Thus we
will return to an error path, and it is up to that code to make forward
progress towards delivering the fatal signal.

[ Description taken from commit 746a272e4414 ("ARM: 8692/1: mm: abort
   uaccess retries upon fatal signal") ]

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>

MIPS: IRQ: Add prototype for function init_IRQ

This commit adds a prototype to fix error at W=1:

arch/mips/kernel/irq.c:52:13: error: no previous prototype for
'init_IRQ' [-Werror=missing-prototypes]

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Revert "MIPS: Octeon: Remove special handling of CONFIG_MIPS_ELF_APPENDED_DTB=y"

This reverts commit d9df9fb901d25b941ab2cfb5b570d91fb2abf7a3.

For the OCTEON boards, it need to patch the built-in DTB before using
it. Previously it judges if it is a built-in DTB by checking
fw_passed_dtb. But after commit 37e5c69ffd41 ("MIPS: head.S: Init
fw_passed_dtb to builtin DTB", the fw_passed_dtb is initialized even
when using built-in DTB. This causes the OCTEON boards boot broken due
to an unpatched built-in DTB is used. Revert the commit d9df9fb901d2 to
restore the codes before the fw_passed_dtb is used and then fix this
issue.

Fixed: 37e5c69ffd41 ("MIPS: head.S: Init fw_passed_dtb to builtin DTB")
Cc: stable@vger.kernel.org
Suggested-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: relocatable: optimize the relocation process

For now, vmlinux relocation functions for relocatable kernel are
implemented as an array of handlers of a particular type.

Convert that array into a single switch-case function to:
 - remove unused arguments;
 - change the return type of simple handlers to void;
 - remove the array and don't use any data at all;
 - avoid using indirect calls;
 - allow the compiler to inline and greatly optimize
   the relocation function[s];

and also mark do_relocations() and show_kernel_relocation() static
as they aren't used anywhere else.

The result on MIPS32 R2 with GCC 10.2 -O2 is:

scripts/bloat-o-meter -c arch/mips/kernel/__relocate.o arch/mips/kernel/relocate.o
add/remove: 0/6 grow/shrink: 1/0 up/down: 356/-640 (-284)
Function                                     old     new   delta
relocate_kernel                              852    1208    +356
apply_r_mips_32_rel                           20       -     -20
apply_r_mips_hi16_rel                         40       -     -40
apply_r_mips_64_rel                           44       -     -44
apply_r_mips_26_rel                          144       -    -144
show_kernel_relocation                       164       -    -164
do_relocations                               228       -    -228
Total: Before=1780, After=1496, chg -15.96%
add/remove: 0/1 grow/shrink: 0/0 up/down: 0/-76 (-76)
Data                                         old     new   delta
reloc_handlers_rel                            76       -     -76
Total: Before=92, After=16, chg -82.61%
add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0 (0)
RO Data                                      old     new   delta
Total: Before=0, After=0, chg +0.00%

All functions were collapsed into the main one, relocate_kernel().

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: module: optimize module relocations processing

For now, module relocation functions are implemented as an array
of handlers of type reloc_handler_t.

Convert that array into a single switch-case function to:
 - remove unused arguments;
 - change the return type of simple handlers to void;
 - remove the array and don't use any data at all;
 - avoid using indirect calls;
 - allow the compiler to inline and greatly optimize
   the relocation function[s].

The result on MIPS32 R2 with GCC 10.2 -O2 is:

scripts/bloat-o-meter -c arch/mips/kernel/__module.o arch/mips/kernel/module.o
add/remove: 1/11 grow/shrink: 1/0 up/down: 876/-1436 (-560)
Function                                     old     new   delta
apply_relocate                               456    1148    +692
apply_r_mips_pc                                -     184    +184
apply_r_mips_none                              8       -      -8
apply_r_mips_32                               16       -     -16
apply_r_mips_64                               76       -     -76
apply_r_mips_highest                          88       -     -88
apply_r_mips_higher                          108       -    -108
apply_r_mips_26                              132       -    -132
apply_r_mips_pc26                            160       -    -160
apply_r_mips_pc21                            160       -    -160
apply_r_mips_pc16                            160       -    -160
apply_r_mips_hi16                            172       -    -172
apply_r_mips_lo16                            356       -    -356
Total: Before=2608, After=2048, chg -21.47%
add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0 (0)
Data                                         old     new   delta
Total: Before=12, After=12, chg +0.00%
add/remove: 0/1 grow/shrink: 0/0 up/down: 0/-248 (-248)
RO Data                                      old     new   delta
reloc_handlers                               248       -    -248
Total: Before=248, After=0, chg -100.00%

All functions were collapsed into a single one that is called
directly by $(srctree)/kernel/module.c.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: VDSO: Use CLANG_FLAGS instead of filtering out '--target='

Commit ee67855ecd9d ("MIPS: vdso: Allow clang's --target flag in VDSO
cflags") allowed the '--target=' flag from the main Makefile to filter
through to the vDSO. However, it did not bring any of the other clang
specific flags for controlling the integrated assembler and the GNU
tools locations (--prefix=, --gcc-toolchain=, and -no-integrated-as).
Without these, we will get a warning (visible with tinyconfig):

arch/mips/vdso/elf.S:14:1: warning: DWARF2 only supports one section per
compilation unit
.pushsection .note.Linux, "a",@note ; .balign 4 ; .long 2f - 1f ; .long
4484f - 3f ; .long 0 ; 1:.asciz "Linux" ; 2:.balign 4 ; 3:
^
arch/mips/vdso/elf.S:34:2: warning: DWARF2 only supports one section per
compilation unit
 .section .mips_abiflags, "a"
 ^

All of these flags are bundled up under CLANG_FLAGS in the main Makefile
and exported so that they can be added to Makefiles that set their own
CFLAGS. Use this value instead of filtering out '--target=' so there is
no warning and all of the tools are properly used.

Cc: stable@vger.kernel.org
Fixes: ee67855ecd9d ("MIPS: vdso: Allow clang's --target flag in VDSO cflags")
Link: https://github.com/ClangBuiltLinux/linux/issues/1256
Reported-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Ingenic: Disable HPTLB for D0 XBurst CPUs too

The JZ4760 has the HPTLB as well, but has a XBurst CPU with a D0 CPUID.

Disable the HPTLB for all XBurst CPUs with a D0 CPUID. In the case where
there is no HPTLB (e.g. for older SoCs), this won't have any side
effect.

Fixes: b02efeb05699 ("MIPS: Ingenic: Disable abandoned HPTLB function.")
Cc: <stable@vger.kernel.org> # 5.4
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Support binutils configured with --enable-mips-fix-loongson3-llsc=yes

From version 2.35, binutils can be configured with
--enable-mips-fix-loongson3-llsc=yes, which means it defaults to
-mfix-loongson3-llsc. This breaks labels which might then point at the
wrong instruction.

The workaround to explicitly pass -mno-fix-loongson3-llsc has been
added in Linux version 5.1, but is only enabled when building a Loongson
64 kernel. As vendors might use a common toolchain for building Loongson
and non-Loongson kernels, just move that workaround to
arch/mips/Makefile. At the same time update the comments to reflect the
current status.

Cc: stable@vger.kernel.org # 5.1+
Cc: YunQiang Su <syq@debian.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Compare __SYNC_loongson3_war against 0

When building with clang when CONFIG_CPU_LOONGSON3_WORKAROUNDS is
enabled:

 In file included from lib/errseq.c:4:
 In file included from ./include/linux/atomic.h:7:
 ./arch/mips/include/asm/atomic.h:52:1: warning: converting the result of
 '<<' to a boolean always evaluates to true
 [-Wtautological-constant-compare]
 ATOMIC_OPS(atomic64, s64)
 ^
 ./arch/mips/include/asm/atomic.h:40:9: note: expanded from macro
 'ATOMIC_OPS'
         return cmpxchg(&v->counter, o, n);
                ^
 ./arch/mips/include/asm/cmpxchg.h:194:7: note: expanded from macro
 'cmpxchg'
         if (!__SYNC_loongson3_war)
              ^
 ./arch/mips/include/asm/sync.h:147:34: note: expanded from macro
 '__SYNC_loongson3_war'
 # define __SYNC_loongson3_war   (1 << 31)
                                    ^

While it is not wrong that the result of this shift is always true in a
boolean context, it is not a problem here. Regardless, the warning is
really noisy so rather than making the shift a boolean implicitly, use
it in an equality comparison so the shift is used as an integer value.

Fixes: 4d1dbfe6cbec ("MIPS: atomic: Emit Loongson3 sync workarounds within asm")
Fixes: a91f2a1dba44 ("MIPS: cmpxchg: Omit redundant barriers for Loongson3")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: pgtable: fix -Wshadow in asm/pgtable.h

Solves the following repetitive warning when building with -Wshadow:

In file included from ./include/linux/pgtable.h:6,
                 from ./include/linux/mm.h:33,
                 from ./include/linux/dax.h:6,
                 from ./include/linux/mempolicy.h:11,
                 from kernel/fork.c:34:
./arch/mips/include/asm/mmu_context.h: In function ‘switch_mm’:
./arch/mips/include/asm/pgtable.h:97:16: warning: declaration of ‘flags’ shadows a previous local [-Wshadow]
   97 |  unsigned long flags;      \
      |                ^~~~~
./arch/mips/include/asm/mmu_context.h:162:2: note: in expansion of macro ‘htw_stop’
  162 |  htw_stop();
      |  ^~~~~~~~
In file included from kernel/fork.c:102:
./arch/mips/include/asm/mmu_context.h:159:16: note: shadowed declaration is here
  159 |  unsigned long flags;
      |                ^~~~~

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: bitops: fix -Wshadow in asm/bitops.h

Solves the following repetitive warning when building with -Wshadow:

In file included from ./include/linux/bitops.h:32,
                 from ./include/linux/kernel.h:11,
                 from ./include/linux/skbuff.h:13,
                 from ./include/linux/if_ether.h:19,
                 from ./include/linux/etherdevice.h:20:
./arch/mips/include/asm/bitops.h: In function ‘test_and_set_bit_lock’:
./arch/mips/include/asm/bitops.h:46:16: warning: declaration of ‘orig’ shadows a previous local [-Wshadow]
   46 |  unsigned long orig, temp;    \
      |                ^~~~
./arch/mips/include/asm/bitops.h:190:10: note: in expansion of macro ‘__test_bit_op’
  190 |   orig = __test_bit_op(*m, "%0",
      |          ^~~~~~~~~~~~~
./arch/mips/include/asm/bitops.h:185:21: note: shadowed declaration is here
  185 |  unsigned long res, orig;
      |                     ^~~~
./arch/mips/include/asm/bitops.h: In function ‘test_and_clear_bit’:
./arch/mips/include/asm/bitops.h:46:16: warning: declaration of ‘orig’ shadows a previous local [-Wshadow]
   46 |  unsigned long orig, temp;    \
      |                ^~~~
./arch/mips/include/asm/bitops.h:236:9: note: in expansion of macro ‘__test_bit_op’
  236 |   res = __test_bit_op(*m, "%1",
      |         ^~~~~~~~~~~~~
./arch/mips/include/asm/bitops.h:229:21: note: shadowed declaration is here
  229 |  unsigned long res, orig;
      |                     ^~~~
./arch/mips/include/asm/bitops.h:46:16: warning: declaration of ‘orig’ shadows a previous local [-Wshadow]
   46 |  unsigned long orig, temp;    \
      |                ^~~~
./arch/mips/include/asm/bitops.h:241:10: note: in expansion of macro ‘__test_bit_op’
  241 |   orig = __test_bit_op(*m, "%0",
      |          ^~~~~~~~~~~~~
./arch/mips/include/asm/bitops.h:229:21: note: shadowed declaration is here
  229 |  unsigned long res, orig;
      |                     ^~~~
./arch/mips/include/asm/bitops.h: In function ‘test_and_change_bit’:
./arch/mips/include/asm/bitops.h:46:16: warning: declaration of ‘orig’ shadows a previous local [-Wshadow]
   46 |  unsigned long orig, temp;    \
      |                ^~~~
./arch/mips/include/asm/bitops.h:273:10: note: in expansion of macro ‘__test_bit_op’
  273 |   orig = __test_bit_op(*m, "%0",
      |          ^~~~~~~~~~~~~
./arch/mips/include/asm/bitops.h:266:21: note: shadowed declaration is here
  266 |  unsigned long res, orig;
      |                     ^~~~

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: select ARCH_WANT_LD_ORPHAN_WARN

Now, after that all the sections are explicitly described and
declared in vmlinux.lds.S, we can enable ld orphan warnings to
prevent from missing any new sections in future.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

vmlinux.lds.h: catch UBSAN's "unnamed data" into data

When building kernel with both LD_DEAD_CODE_DATA_ELIMINATION and
UBSAN, LLVM stack generates lots of "unnamed data" sections:

ld.lld: warning: net/built-in.a(netfilter/utils.o): (.data.$__unnamed_2)
is being placed in '.data.$__unnamed_2'
ld.lld: warning: net/built-in.a(netfilter/utils.o): (.data.$__unnamed_3)
is being placed in '.data.$__unnamed_3'
ld.lld: warning: net/built-in.a(netfilter/utils.o): (.data.$__unnamed_4)
is being placed in '.data.$__unnamed_4'
ld.lld: warning: net/built-in.a(netfilter/utils.o): (.data.$__unnamed_5)
is being placed in '.data.$__unnamed_5'

[...]

Also handle this by adding the related sections to generic definitions.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

vmlinux.lds.h: catch compound literals into data and BSS

When building kernel with LD_DEAD_CODE_DATA_ELIMINATION, LLVM stack
generates separate sections for compound literals, just like in case
with enabled LTO [0]:

ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o):
(.data..compoundliteral.14) is being placed in
'.data..compoundliteral.14'
ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o):
(.data..compoundliteral.15) is being placed in
'.data..compoundliteral.15'
ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o):
(.data..compoundliteral.16) is being placed in
'.data..compoundliteral.16'
ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o):
(.data..compoundliteral.17) is being placed in
'.data..compoundliteral.17'

[...]

Handle this by adding the related sections to generic definitions
as suggested by Sami [0].

[0] https://lore.kernel.org/lkml/20201211184633.3213045-3-samitolvanen@google.com

Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: vmlinux.lds.S: explicitly declare .got table

LLVM stack generates GOT table when building the kernel:

ld.lld: warning: <internal>:(.got) is being placed in '.got'

According to the debug assertions, it's not zero-sized and thus can't
be handled the way it's done for x86.
Also use the ARM64 path here and place it at the end of .text section.

Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols

According to linker warnings, both GCC and LLVM generate '.rel.dyn'
symbols:

mips-alpine-linux-musl-ld: warning: orphan section `.rel.dyn'
from `init/main.o' being placed in section `.rel.dyn'

Link-time assertion shows that this section is sometimes empty,
sometimes not, depending on machine bitness and the compiler [0]:

  LD      .tmp_vmlinux.kallsyms1
mips64-linux-gnu-ld: Unexpected run-time relocations (.rel) detected!

Just use the ARM64 approach and declare it in vmlinux.lds.S closer
to __init_end.

[0] https://lore.kernel.org/linux-mips/20210109111259.GA4213@alpha.franken.de

Reported-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: properly stop .eh_frame generation

Commit 866b6a89c6d1 ("MIPS: Add DWARF unwinding to assembly") added
-fno-asynchronous-unwind-tables to KBUILD_CFLAGS to prevent compiler
from emitting .eh_frame symbols.
However, as MIPS heavily uses CFI, that's not enough. Use the
approach taken for x86 (as it also uses CFI) and explicitly put CFI
symbols into the .debug_frame section (except for VDSO).
This allows us to drop .eh_frame from DISCARDS as it's no longer
being generated.

Fixes: 866b6a89c6d1 ("MIPS: Add DWARF unwinding to assembly")
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS

Discard GNU attributes (MIPS FP type, GNU Hash etc.) at link time
as kernel doesn't use it at all.
Solves a dozen of the following ld warnings (one per every file):

mips-alpine-linux-musl-ld: warning: orphan section `.gnu.attributes'
from `arch/mips/kernel/head.o' being placed in section
`.gnu.attributes'
mips-alpine-linux-musl-ld: warning: orphan section `.gnu.attributes'
from `init/main.o' being placed in section `.gnu.attributes'

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: CPS: don't create redundant .text.cps-vec section

A number of symbols from arch/mips/kernel/cps-vec.S is explicitly
placed into '.text.cps-vec' section.
There are no direct references to this section, so there's no need
to form it. '.balign 0x1000' directive will work anyway.

Moreover, this section was being placed in vmlinux differently
depending on CONFIG_LD_DEAD_CODE_DATA_ELIMINATION:
 - with this option enabled, '.text.cps-vec' was being caught
   by '.text.[0-9a-zA-Z_]*' from include/asm-generic/vmlinux.lds.h;
 - without this option, '.text.cps-vec' was being caught
   by discouraging '.text.*' from arch/mips/kernel/vmlinux.lds.S.

'.text.*' should not be used in vmlinux linker scripts at all as it
silently catches any orphan text sections.
So, remove both '.section .text.cps-vec' and '.text.*' from cps-vec.S
and vmlinux.lds.S respectively. As said, this does not affect related
functions alignment:

80116000 T mips_cps_core_entry
80116028 t not_nmi
80116200 T excep_tlbfill
80116280 T excep_xtlbfill
80116300 T excep_cache
80116380 T excep_genex
80116400 T excep_intex
80116480 T excep_ejtag
80116490 T mips_cps_core_init

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section

MIPS uses its own declaration of rwdata, and thus it should be kept
in sync with the asm-generic one. Currently PAGE_ALIGNED_DATA() is
missing from the linker script, which emits the following ld
warnings:

mips-alpine-linux-musl-ld: warning: orphan section
`.data..page_aligned' from `arch/mips/kernel/vdso.o' being placed
in section `.data..page_aligned'
mips-alpine-linux-musl-ld: warning: orphan section
`.data..page_aligned' from `arch/mips/vdso/vdso-image.o' being placed
in section `.data..page_aligned'

Add the necessary declaration, so the mentioned structures will be
placed in vmlinux as intended:

ffffffff80630580 D __end_once
ffffffff80630580 D __start___dyndbg
ffffffff80630580 D __start_once
ffffffff80630580 D __stop___dyndbg
ffffffff80634000 d mips_vdso_data
ffffffff80638000 d vdso_data
ffffffff80638580 D _gp
ffffffff8063c000 T __init_begin
ffffffff8063c000 D _edata
ffffffff8063c000 T _sinittext

->

ffffffff805a4000 D __end_init_task
ffffffff805a4000 D __nosave_begin
ffffffff805a4000 D __nosave_end
ffffffff805a4000 d mips_vdso_data
ffffffff805a8000 d vdso_data
ffffffff805ac000 D mmlist_lock
ffffffff805ac080 D tasklist_lock

Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO")
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: lantiq: irq: register the interrupt controllers with irqchip_init

Add support for more interrupt controllers by switching from
of_irq_init() to irqchip_init() in Lantiq's arch_init_irq(). This
requires switching the ICU interrupt controller to use
IRQCHIP_DECLARE(), like a real irqchip driver would do.

This is needed for future changes when new irqchip drivers are
implemented:
- a dedicated driver for the EIU interrupt controller
- a driver for the MSI PIC (Programmable Interrupt Controller) found on
  VRX200 and newer SoCs
- ..or any other driver which uses IRQCHIP_DECLARE

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

dt-bindings: mips: lantiq: Document Lantiq Xway DMA bindings

Document the Lantiq Xway SoC DMA Controller DT bindings.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

dt-bindings: mips: lantiq: Document Lantiq Xway EBU bindings

Document the Lantiq Xway SoC series External Bus Unit (EBU) bindings.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

dt-bindings: mips: lantiq: Document Lantiq Xway CGU bindings

Document the Lantiq Xway SoC series Clock Generation Unit (CGU) bindings.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

dt-bindings: mips: lantiq: Document Lantiq Xway PMU bindings

Document the Lantiq Xway SoC series Power Management Unit (PMU) bindings.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: bitops: Fix reference to ffz location

Unlike most other architectures, MIPS defines ffz() below ffs().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: UAPI: unexport unistd_nr_{n32,n64,o32}.h

unistd_nr_{n32,n64,o32}.h are needed only by include/asm/unistd.h,
which is a kernel-side header file, and their contents is generally
not for userland use.
Move their target destination from include/generated/uapi/asm/ to
include/generated/asm/ to disable exporting them as UAPI headers.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: lantiq: Explicitly compare LTQ_EBU_PCC_ISTAT against 0

When building xway_defconfig with clang:

arch/mips/lantiq/irq.c:305:48: error: use of logical '&&' with constant
operand [-Werror,-Wconstant-logical-operand]
        if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0) && LTQ_EBU_PCC_ISTAT)
                                                      ^ ~~~~~~~~~~~~~~~~~
arch/mips/lantiq/irq.c:305:48: note: use '&' for a bitwise operation
        if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0) && LTQ_EBU_PCC_ISTAT)
                                                      ^~
                                                      &
arch/mips/lantiq/irq.c:305:48: note: remove constant to silence this
warning
        if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0) && LTQ_EBU_PCC_ISTAT)
                                                     ~^~~~~~~~~~~~~~~~~~~~
1 error generated.

Explicitly compare the constant LTQ_EBU_PCC_ISTAT against 0 to fix the
warning. Additionally, remove the unnecessary parentheses as this is a
simple conditional statement and shorthand '== 0' to '!'.

Fixes: 3645da0276ae ("OF: MIPS: lantiq: implement irq_domain support")
Link: https://github.com/ClangBuiltLinux/linux/issues/807
Reported-by: Dmitry Golovin <dima@golovin.in>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: init: move externs to header file

This commit fixes the following checkpatch warnings:

    WARNING: externs should be avoided in .c files

    This is a warning for placing declarations in a ".c" file.
    This fix removes the declaration in ".c" and adds it to
    the common header file.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: zboot: Avoid endless loop in clear BSS.

Commit 2ee1503e546f ("MIPS: zboot: head.S clean up").

After .noreorder removed, clear BSS fall into endless loop. The bne
instruction will add nop to the delay slot at compile time. So a0
register will not increment by 4. Fix it and clear BSS from _edata
to (_end - 1).

Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Remove empty prom_free_prom_memory functions

Most of the prom_free_prom_memory functions are empty. With
a new weak prom_free_prom_memory() we can remove all of them.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>

MIPS: c-r4k: Fix section mismatch for loongson2_sc_init

When building with clang, the following section mismatch warning occurs:

WARNING: modpost: vmlinux.o(.text+0x24490): Section mismatch in
reference from the function r4k_cache_init() to the function
.init.text:loongson2_sc_init()

This should have been fixed with commit ad4fddef5f23 ("mips: fix Section
mismatch in reference") but it was missed. Remove the improper __init
annotation like that commit did.

Fixes: 078a55fc824c ("MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code")
Link: https://github.com/ClangBuiltLinux/linux/issues/787
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Use address-of operator on section symbols

When building xway_defconfig with clang:

arch/mips/lantiq/prom.c:82:23: error: array comparison always evaluates
to true [-Werror,-Wtautological-compare]
        else if (__dtb_start != __dtb_end)
                             ^
1 error generated.

These are not true arrays, they are linker defined symbols, which are
just addresses. Using the address of operator silences the warning
and does not change the resulting assembly with either clang/ld.lld
or gcc/ld (tested with diff + objdump -Dr). Do the same thing across
the entire MIPS subsystem to ensure there are no more warnings around
this type of comparison.

Link: https://github.com/ClangBuiltLinux/linux/issues/1232
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: loongson64: smp.c: Fix block comment coding style

This patch fixes:
"WARNING: Block comments use a trailing */ on a separate line"
by checkpatch.pl

Signed-off-by: siyanteng <siyanteng@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Kill RM7K & RM9K IRQ Code

RM7000 IRQ driver never got really used by any of the platform,
and rm9k_cpu_irq_init only exist in a header.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: perf: Add support for OCTEON III perf events.

According to Hardware Reference Manual, OCTEON III
are mostly same as previous OCTEON models. So just
enable them and extend supported event code.
0x3e and 0x3f still reserved.

Signed-off-by: Jia Qingtong <jiaqingtong97@163.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Loongson64: Set cluster for cores

cluster is required for cacheinfo to set shared_cpu_map correctly.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: cacheinfo: Add missing VCache

Victim Cache is defined by Loongson as per-core unified
private Cache.
Add this into cacheinfo and make cache levels selfincrement
instead of hardcode levels.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: zboot: head.S clean up

.cprestore is removed as we don't expect Position Independent
zboot ELF.

.noreorder is also removed and rest instructions are massaged
to improve readability.

t9 register is used for indirect jump as MIPS ABI requirement.

start label is removed as it already defined in LEAF.

Reported-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Loongson64: Give chance to build under !CONFIG_NUMA and !CONFIG_SMP

In the current code, we can not build under !CONFIG_NUMA and !CONFIG_SMP
on the Loongson64 platform, it seems bad for the users who just want to
use pure single core (not nosmp) to debug, so do the following things to
give them a chance:

(1) Do not select NUMA and SMP for MACH_LOONGSON64 in Kconfig, make NUMA
depends on SMP, and then just set them in the loongson3_defconfig.
(2) Move szmem() from numa.c to init.c and add prom_init_memory() under
!CONFIG_NUMA.
(3) Clean up szmem() due to the statements of case SYSTEM_RAM_LOW and
SYSTEM_RAM_HIGH are the same.
(4) Remove the useless declaration of prom_init_memory() and add the
declaration of szmem() in loongson.h to avoid build error.

Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: No need to check CPU 0 in cps_cpu_disable()

After commit 9cce844abf07 ("MIPS: CPU#0 is not hotpluggable"),
c->hotpluggable is 0 for CPU 0 and it will not generate a control
file in sysfs for this CPU:

[root@linux loongson]# cat /sys/devices/system/cpu/cpu0/online
cat: /sys/devices/system/cpu/cpu0/online: No such file or directory
[root@linux loongson]# echo 0 > /sys/devices/system/cpu/cpu0/online
bash: /sys/devices/system/cpu/cpu0/online: Permission denied

So no need to check CPU 0 in cps_cpu_disable(), just remove it.

Reported-by: liwei (GF) <liwei391@huawei.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

mips: pci: convert comma to semicolon

Replace a comma between expression statements by a semicolon.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

mips: kernel: convert comma to semicolon

Replace a comma between expression statements by a semicolon.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Linux 5.11-rc1

proc mountinfo: make splice available again

Since commit 36e2c7421f02 ("fs: don't allow splice read/write without
explicit ops") we've required that file operation structures explicitly
enable splice support, rather than falling back to the default handlers.

Most /proc files use the indirect 'struct proc_ops' to describe their
file operations, and were fixed up to support splice earlier in commits
40be821d627c..b24c30c67863, but the mountinfo files interact with the
VFS directly using their own 'struct file_operations' and got missed as
a result.

This adds the necessary support for splice to work for /proc/*/mountinfo
and friends.

Reported-by: Joan Bruguera Micó <joanbrugueram@gmail.com>
Reported-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=209971
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'ntb-5.11' of git://github.com/jonmason/ntb

Pull NTB fixes from Jon Mason:
 "Bug fix for IDT NTB and Intel NTB LTR management support"

* tag 'ntb-5.11' of git://github.com/jonmason/ntb:
  ntb: intel: add Intel NTB LTR vendor support for gen4 NTB
  ntb: idt: fix error check in ntb_hw_idt.c

Merge branch 'linus' of git://git./linux/kernel/git/herbert/crypto-2.6

Pull crypto fixes from Herbert Xu:
 "Fix a number of autobuild failures due to missing Kconfig
  dependencies"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: qat - add CRYPTO_AES to Kconfig dependencies
  crypto: keembay - Add dependency on HAS_IOMEM
  crypto: keembay - CRYPTO_DEV_KEEMBAY_OCS_AES_SM4 should depend on ARCH_KEEMBAY

Merge tag 'objtool-urgent-2020-12-27' of git://git./linux/kernel/git/tip/tip

Pull objtool fix from Ingo Molnar:
 "Fix a segfault that occurs when built with Clang"

* tag 'objtool-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix seg fault with Clang non-section symbols

Merge tag 'locking-urgent-2020-12-27' of git://git./linux/kernel/git/tip/tip

Pull locking fixes from Ingo Molnar:
 "Misc fixes/updates:

   - Fix static keys usage in module __init sections

   - Add separate MAINTAINERS entry for static branches/calls

   - Fix lockdep splat with CONFIG_PREEMPTIRQ_EVENTS=y tracing"

* tag 'locking-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  softirq: Avoid bad tracing / lockdep interaction
  jump_label/static_call: Add MAINTAINERS
  jump_label: Fix usage in module __init

Merge tag 'timers-urgent-2020-12-27' of git://git./linux/kernel/git/tip/tip

Pull timer fixes from Ingo Molnar:
 "Update/fix two CPU sanity checks in the hotplug and the boot code, and
  fix a typo in the Kconfig help text.

  [ Context: the first two commits are the result of an ongoing
    annotation+review work of (intentional) tick_do_timer_cpu() data
    races reported by KCSAN, but the annotations aren't fully cooked
    yet ]"

* tag 'timers-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Fix spelling mistake in Kconfig "fullfill" -> "fulfill"
  tick/sched: Remove bogus boot "safety" check
  tick: Remove pointless cpu valid check in hotplug code

Merge tag 'sched-urgent-2020-12-27' of git://git./linux/kernel/git/tip/tip

Pull scheduler fix from Ingo Molnar:
 "Fix a context switch performance regression"

* tag 'sched-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Optimize finish_lock_switch()

mfd: ab8500-debugfs: Remove extraneous seq_putc

Commit c9a3c4e637ac ("mfd: ab8500-debugfs: Remove extraneous curly
brace") removed a left-over curly brace that caused build failures, but
Joe Perches points out that the subsequent 'seq_putc()' should also be
removed, because the commit that caused all these problems already added
the final '\n' to the seq_printf() above it.

Reported-by: Joe Perches <joe@perches.com>
Fixes: 886c8121659d ("mfd: ab8500-debugfs: Remove the racy fiddling with irq_desc")
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'pci-v5.11-fixes-1' of git://git./linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:

 - Fix a tegra enumeration regression (Rob Herring)

 - Fix a designware-host check that warned on *success*, not failure
   (Alexander Lobakin)

* tag 'pci-v5.11-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: dwc: Fix inverted condition of DMA mask setup warning
  PCI: tegra: Fix host link initialization

mfd: ab8500-debugfs: Remove extraneous curly brace

Clang errors:

  drivers/mfd/ab8500-debugfs.c:1526:2: error: non-void function does not return a value [-Werror,-Wreturn-type]
          }
          ^
  drivers/mfd/ab8500-debugfs.c:1528:2: error: expected identifier or '('
  return 0;
          ^
  drivers/mfd/ab8500-debugfs.c:1529:1: error: extraneous closing brace ('}')
  }
  ^
  3 errors generated.

The cleanup in ab8500_interrupts_show left a curly brace around, remove
it to fix the error.

Fixes: 886c8121659d ("mfd: ab8500-debugfs: Remove the racy fiddling with irq_desc")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

PCI: dwc: Fix inverted condition of DMA mask setup warning

Commit 660c486590aa ("PCI: dwc: Set 32-bit DMA mask for MSI target address
allocation") added dma_mask_set() call to explicitly set 32-bit DMA mask
for MSI message mapping, but for now it throws a warning on ret == 0, while
dma_set_mask() returns 0 in case of success.

Fix this by inverting the condition.

[bhelgaas: join string to make it greppable]
Fixes: 660c486590aa ("PCI: dwc: Set 32-bit DMA mask for MSI target address allocation")
Link: https://lore.kernel.org/r/20201222150708.67983-1-alobakin@pm.me
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: tegra: Fix host link initialization

Commit b9ac0f9dc8ea ("PCI: dwc: Move dw_pcie_setup_rc() to DWC common
code") broke enumeration of downstream devices on Tegra:

In non-working case (next-20201211):

  0001:00:00.0 PCI bridge: NVIDIA Corporation Device 1ad2 (rev a1)
  0001:01:00.0 SATA controller: Marvell Technology Group Ltd. Device 9171 (rev 13)
  0005:00:00.0 PCI bridge: NVIDIA Corporation Device 1ad0 (rev a1)

In working case (v5.10-rc7):

  0001:00:00.0 PCI bridge: Molex Incorporated Device 1ad2 (rev a1)
  0001:01:00.0 SATA controller: Marvell Technology Group Ltd. Device 9171 (rev 13)
  0005:00:00.0 PCI bridge: Molex Incorporated Device 1ad0 (rev a1)
  0005:01:00.0 PCI bridge: PLX Technology, Inc. Device 3380 (rev ab)
  0005:02:02.0 PCI bridge: PLX Technology, Inc. Device 3380 (rev ab)
  0005:03:00.0 USB controller: PLX Technology, Inc. Device 3380 (rev ab)

The problem seems to be dw_pcie_setup_rc() is now called twice before and
after the link up handling. The fix is to move Tegra's link up handling to
.start_link() function like other DWC drivers. Tegra is a bit more
complicated than others as it re-inits the whole DWC controller to retry
the link. With this, the initialization ordering is restored to match the
prior sequence.

Fixes: b9ac0f9dc8ea ("PCI: dwc: Move dw_pcie_setup_rc() to DWC common code")
Link: https://lore.kernel.org/r/20201218143905.1614098-1-robh@kernel.org
Reported-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Tested-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Vidya Sagar <vidyas@nvidia.com>

drm/amd/display: avoid uninitialized variable warning

clang (quite rightly) complains fairly loudly about the newly added
mpc1_get_mpc_out_mux() function returning an uninitialized value if the
'opp_id' checks don't pass.

This may not happen in practice, but the code really shouldn't return
garbage if the sanity checks don't pass.

So just initialize 'val' to zero to avoid the issue.

Fixes: 110b055b2827 ("drm/amd/display: add getter routine to retrieve mpcc mux")
Cc: Josip Pavic <Josip.Pavic@amd.com>
Cc: Bindu Ramamurthy <bindu.r@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'perf-tools-2020-12-24' of git://git./linux/kernel/git/acme/linux

Pull more perf tools updates from Arnaldo Carvalho de Melo:

 - Refactor 'perf stat' per CPU/socket/die/thread aggregation fixing use
   cases in ARM machines.

 - Fix memory leak when synthesizing SDT probes in 'perf probe'.

 - Update kernel header copies related to KVM, epol_pwait. msr-index and
   powerpc and s390 syscall tables.

* tag 'perf-tools-2020-12-24' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (24 commits)
  perf probe: Fix memory leak when synthesizing SDT probes
  perf stat aggregation: Add separate thread member
  perf stat aggregation: Add separate core member
  perf stat aggregation: Add separate die member
  perf stat aggregation: Add separate socket member
  perf stat aggregation: Add separate node member
  perf stat aggregation: Start using cpu_aggr_id in map
  perf cpumap: Drop in cpu_aggr_map struct
  perf cpumap: Add new map type for aggregation
  perf stat: Replace aggregation ID with a struct
  perf cpumap: Add new struct for cpu aggregation
  perf cpumap: Use existing allocator to avoid using malloc
  perf tests: Improve topology test to check all aggregation types
  perf tools: Update s390's syscall.tbl copy from the kernel sources
  perf tools: Update powerpc's syscall.tbl copy from the kernel sources
  perf s390: Move syscall.tbl check into check-headers.sh
  perf powerpc: Move syscall.tbl check to check-headers.sh
  tools headers UAPI: Synch KVM's svm.h header with the kernel
  tools kvm headers: Update KVM headers from the kernel sources
  tools headers UAPI: Sync KVM's vmx.h header with the kernel sources
  ...