Using the __raw_{read,write}{b,w,l} functions to perform
repeatable MMIO could result in problems if the host bus
does not match the endianness of the PCI/ISA. This problem
is visible on big-endian SEAD3 configurations after commit
2925f6c0
"net: smc911x: use io{read,write}*_rep accessors". This effectively
moves away from using the __mem_* variants to __raw_* ones
and causes a kernel bug as follows:

Call Trace:
CPU 0 Unable to handle kernel paging request at virtual address 00000000,
epc == 00000000, ra == 8012b3b0
Oops[#1]:
Cpu 0
$ 0   : 00000000 00000065 00000000 00000004
$ 4   : 00000000 00000000 9a82dd60 00000000
$ 8   : 00000000 00000000 a00ae278 00000007
$12   : 0000000e 00000011 804c4228 ffff9411
$16   : 00000100 00000000 80560000 807fc6d0
$20   : 807fc8d0 807fcad0 807fbec0 00000100
$24   : 00009150 80109be0
$28   : 9a82c000 9a82dd28 00000001 8012b3b0
Hi    : 00000000
Lo    : 00000000
epc   : 00000000   (null)
    Not tainted
ra    : 8012b3b0 call_timer_fn.isra.39+0x24/0x84
Status: 10009503    KERNEL EXL IE
Cause : 00800808
BadVA : 00000000
PrId  : 00019c20 (MIPS M14Kc)
Modules linked in:
Process swapper (pid: 1, threadinfo=9a82c000, task=9a82ba18, tls=00000000)
Stack : 00000040 00000000 00000007 8056732c 80580000 00000001 9a82dd60 00200200
        80560000 8012b598 8056732c 80580000 00000001 00000000 9a82dd60 9a82dd60
        00000000 807fbd44 807fbd40 805664e0 0000000a 80800000 00000004 80125924
        0000fda0 000007f0 80000000 00000001 80800000 007f0000 00200140 80166338
        00000000 8100fda0 0000fda0 000007f0 80000000 00000001 80800000 007f0000
        ...
Call Trace:
[<8012b598>] run_timer_softirq+0x188/0x1f4
[<80125924>] __do_softirq+0xc4/0x18c
[<80166338>] handle_percpu_irq+0x54/0x84
[<80125aa4>] do_softirq+0x68/0x70
[<80103b50>] do_IRQ+0x18/0x28
[<80125d1c>] irq_exit+0x94/0xc0
[<80125aa4>] do_softirq+0x68/0x70
[<80102130>] ret_from_irq+0x0/0x4
[<80102130>] ret_from_irq+0x0/0x4
[<80125d1c>] irq_exit+0x94/0xc0
[<803165b0>] __bzero+0xd4/0x164
[<80346d0c>] mem32_serial_out+0x0/0x1c
[<8010d4ac>] free_init_pages+0x98/0xfc
[<80180a08>] free_hot_cold_page+0x2c/0x1c4
[<80180bd8>] __free_pages+0x38/0x98
[<8010d4a0>] free_init_pages+0x8c/0xfc
[<8010d4ac>] free_init_pages+0x98/0xfc
[<8049fb04>] kernel_init+0x28/0x15c
[<80147484>] schedule_tail+0x1c/0x60
[<8049fadc>] kernel_init+0x0/0x15c
[<80102178>] ret_from_kernel_thread+0x14/0x1c
[<8040a06f>] skb_pad+0xe7/0x13c
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: Steve Glendinning <steve.glendinning@shawell.net>
Cc: Ben Boeckel <mathstuf@gmail.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Cc: Jeffrey Deans <Jeffrey.Deans@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6672/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Having #ifdefs just to guard comments is not really helpful
so drop them. Moreover, the code wasn't really reached anyway
since there is a #ifndef CONFIG_CPU_MIPSR2 on the top of the file.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8513/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NIsamu Mogi <isamu@leafytree.jp>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8292/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Also include asm/mmu_context.h for ASID_MASK.
Signed-off-by: NIsamu Mogi <isamu@leafytree.jp>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8291/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit cf62a8b8 ("MIPS: lib: memcpy: Use macro to build the
copy_user code") switched to a macro in order to build the memcpy
symbols in preparation for the EVA support. However, this commit
also removed the NOP instruction after the 'jr ra' when returning
back to the caller. This had no visible side-effects since the next
instruction was a load to the t0 register which was already in the
clobbered list, but it may have undesired effects in the future
if some other code is introduced in between the .Ldone and
the .Ll_exc_copy labels.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # v3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8512/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Virtual page number of R3000 in entryhi is 20 bit from MSB. But in
dump_tlb(), the bit mask to read it from entryhi is 19 bit (0xffffe000).
The patch fixes that to 0xfffff000.
Signed-off-by: NIsamu Mogi <isamu@leafytree.jp>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8290/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

We were returning maxlen like the userland strnlen if no '\0' character
was encountered while the kernel version is expected to return a value
larger than maxlen.  Fixed to return maxlen + 1.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: Nchenj <chenj@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: chenhc@lemote.com
Patchwork: https://patchwork.linux-mips.org/patch/7542/
Patchwork: https://patchwork.linux-mips.org/patch/7550/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This small update to the previous fix to __delay removes a conditional
around the ABI-dependent subtraction operation within an inline asm in
favor to the standard <asm/asm.h> LONG_SUBU macro.  No change in code
produced.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6703/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This change reverts most of commit
60724ca5 [MIPS: IP checksums: Remove
unncessary .set pseudos] that introduced warnings with the
CPU_DADDI_WORKAROUNDS option set:

arch/mips/lib/csum_partial.S: Assembler messages:
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3"
[...]
arch/mips/lib/csum_partial.S:577: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:577: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:577: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3"
arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3"
[and so on, and so on...]

The warnings are benign and good code is produced regardless because no
macros that'd use the assembler's temporary register are involved, however
the `.set noat' directives removed by the commit referred are crucial to
guarantee this is still going to be the case after any changes in the
future.  Therefore they need to be brought back to place which this
change does.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6686/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This corrects assembler warnings and broken code generated in
__strncpy_from_user_asm:

arch/mips/lib/strncpy_user.S: Assembler messages:
arch/mips/lib/strncpy_user.S:52: Warning: Macro instruction expanded into
multiple instructions in a branch delay slot

with the CPU_DADDI_WORKAROUNDS option set.  The function schedules delay
slots manually where there is really no need to as GAS is happy to do it
all itself, so undo it all and remove `.set noreorder'.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6685/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

With CPU_DADDI_WORKAROUNDS enabled __delay assembles with a macro in a
branch delay slot:

{standard input}: Assembler messages:
{standard input}:18: Warning: Macro instruction expanded into multiple
instructions in a branch delay slot

and broken code results:

0000000000000000 <__delay>:
   0:	1480ffff 	bnez	a0,0 <__delay>
   4:	24010001 	li	at,1
   8:	0081202f 	dsubu	a0,a0,at
   c:	03e00008 	jr	ra
  10:	00000000 	nop
  14:	00000000 	nop

Consequently the function loops indefinitely, showing up prominently as a
hang in the delay loop calibration at bootstrap.

This change corrects the problem by forcing the immediate 1 into a
register while keeping code produced identical where CPU_DADDI_WORKAROUNDS
is disabled.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6669/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Use EVA specific functions to read and write data to
user address space.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

In preparation for EVA support, we use a macro to build the
__csum_partial_copy_user main code so it can be shared across
multiple implementations. EVA uses the same code but it replaces
the load/store/prefetch instructions with the EVA specific ones
therefore using a macro avoids unnecessary code duplications.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Each load/store macro always adds an entry to the __ex_table
using the EXC macro. There are cases where a load instruction may
never fail such as when we are sure the load happens in the kernel
address space. Therefore, we merge these the EXC and LOADX/STOREX
macros into a single one. We also expand the argument list in the EXC
macro to make the macro more flexible. The extra 'type' argument is not
used by this commit, but it will be used when EVA support is added to
memcpy.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

The 'copy_user' symbol can be used to copy from or to
userland so we will use two different symbols for these
operations. This makes no difference in the existing code,
but when the core is operating in EVA mode, different instructions
need to be used to read and write to userland address space.
The old function has also been renamed to 'copy_kernel' to denote
that it is suitable for copy data to and from kernel space.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Build the __bzero function using the EVA load/store instructions
when operating in the EVA mode. This function is only used when
accessing user code so there is no need to build two distinct symbols
for user and kernel operations respectively.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Build the __bzero symbol using a macor. In EVA mode we will
need to use similar code to do the userspace load operations so
it is better if we use a macro to avoid code duplications.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Add copy_{to,from,in}_user when the CPU operates in EVA mode.
This is necessary so the EVA specific instructions can be used
to perform the virtual to physical translation for user space
addresses. We will use the non-EVA functions to read from kernel
if needed.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

The code can be shared between EVA and non-EVA configurations,
therefore use a macro to build it to avoid code duplications.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

In preparation for EVA support, the PREF macro is split into two
separate macros, PREFS and PREFD, for source and destination data
prefetching respectively.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Each load/store macro always adds an entry to the __ex_table
using the EXC macro. Therefore, these load/store macros are now merged
with the EXC one. The argument list is also expanded in order to make
the macro more flexible. The extra 'type' argument is not used by this
commit, but it will be used when the EVA support is added to the memcpy.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

In non-EVA mode, strncpy_from_user* aliases are used for the
strncpy_from_kernel* symbols since the code is identical. In EVA
mode, new strcpy_from_user* symbols are used which use the EVA
specific instructions to load values from userspace.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Build the __strncpy_from_user symbol using a macro. In EVA mode we will
need to use similar code to do the userspace load operations so
it is better if we use a macro to avoid code duplications.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

In non-EVA mode, strlen_user* aliases are used for the
strlen_kernel* symbols since the code is identical. In EVA
mode, new strlen_user* symbols are used which use the EVA
specific instructions to load values from userspace.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Build the __strlen_user symbol using a macro. In EVA mode we will
need to use similar code to do the userspace load operations so
it is better if we use a macro to avoid code duplications.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

In non-EVA mode, a strlen_user* alias is used for the
strlen_kernel* symbols since the code is identical. In EVA
mode, a new strlen_user* symbol is used which uses the EVA
specific instructions to load values from userspace.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

Build the __strnlen_user symbol using a macro. In EVA mode we will
need to use similar code to do the userspace load operations so
it is better if we use a macro to avoid code duplications.
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>

None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6320/

commit 3747069b25e419f6b51395f48127e9812abc3596 upstream.

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit  -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings.  In any case, they are temporary and harmless.

Here, we remove all the MIPS __cpuinit from C code and __CPUINIT
from asm files.  MIPS is interesting in this respect, because there
are also uasm users hiding behind their own renamed versions of the
__cpuinit macros.

[1] https://lkml.org/lkml/2013/5/20/589

[ralf@linux-mips.org: Folded in Paul's followup fix.]
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5494/
Patchwork: https://patchwork.linux-mips.org/patch/5495/
Patchwork: https://patchwork.linux-mips.org/patch/5509/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This reverts commit d532f3d2.

The original commit has several problems:

1) Doesn't work with 64-bit kernels.

2) Calls TLBMISS_HANDLER_SETUP() before the code is generated.

3) Calls TLBMISS_HANDLER_SETUP() twice in per_cpu_trap_init() when
   only one call is needed.

[ralf@linux-mips.org: Also revert the bits of the ASID patch which were
hidden in the KVM merge.]
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5242/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Optimise 'strnlen' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: NSteven J. Hill <Steven.Hill@imgtec.com>

Optimise 'strlen' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: NSteven J. Hill <Steven.Hill@imgtec.com>

Optimise 'strncpy' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: NSteven J. Hill <Steven.Hill@imgtec.com>

Optimise 'memset' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: NSteven J. Hill <Steven.Hill@imgtec.com>

Original patch by Ralf Baechle and removed by Harold Koerfgen
with commit f67e4ffc79905482c3b9b8c8dd65197bac7eb508. This
allows for more generic kernels since the size of the ASID
and corresponding masks can be determined at run-time. This
patch is also required for the new Aptiv cores and has been
tested on Malta and Malta Aptiv platforms.

[ralf@linux-mips.org: Added relevant part of fix
https://patchwork.linux-mips.org/patch/5213/]
Signed-off-by: NSteven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The operations on the bitmap pointers are protected by "memory"
clobbering raw_local_irq_{save,restore}(), so there is no need for
volatile here.  By removing the volatile we get better code generation
out of the compiler.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4966/Acked-by: NJohn Crispin <blogic@openwrt.org>