On systems that support MT ASE multithreading (ie. VPEs) we are very
likely to want to include that support as default. Rather than setting
it in various defconfigs, simply make CONFIG_MIPS_MT_SMP default y such
that systems which select CONFIG_SYS_SUPPORTS_MULTITHREADING get it by
default.

As well as allowing us to remove the selection of CONFIG_MIPS_MT_SMP
from various defconfigs, this also allows the generated generic
defconfigs which derive from generic_defconfig to automatically gain
support for MT ASE SMP when building for a suitable (pre-MIPSr6) ISA.

For malta_kvm_guest_defconfig CONFIG_MIPS_MT_SMP is explicitly disabled
since enabling SMP implicitly disables CONFIG_KVM_GUEST, which depends
on CONFIG_BROKEN_ON_SMP.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16947/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Modify the functions we use to read information about the topology of
the system (the number of cores, VPs & IOCUs that it contains) in order
to take into account multiple clusters, and provide a new function to
determine the number of clusters in the system.

Users of these functions are modified only such that they continue to
build successfully - having them actually handle multiple clusters is
left to further patches.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17016/
Patchwork: https://patchwork.linux-mips.org/patch/17218/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Move _save_fp(), _restore_fp(), _save_msa(), _restore_msa(),
_init_msa_upper() & _init_fpu() out of r4k_switch.S & into r4k_fpu.S.
This allows us to clean up the way in which Octeon includes the default
r4k implementations of these FP functions despite replacing resume(),
and makes CONFIG_R4K_FPU more straightforwardly represent all
configurations that have an R4K-style FPU, including Octeon.

Besides cleaning up this will be useful for later patches which disable
FP support.

[ralf@linux-mips.org: Fixed build issues reported by Arnd Bergmann
<arnd@arndb.de>]
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16237/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The kernel contains a small amount of incomplete code aimed at
supporting old R6000 CPUs. This is:

  - Unused, as no machine selects CONFIG_SYS_HAS_CPU_R6000.

  - Broken, since there are glaring errors such as r6000_fpu.S moving
    the FCSR register to t1, then ignoring it & instead saving t0 into
    struct sigcontext...

  - A maintenance headache, since it's code that nobody can test which
    nevertheless imposes constraints on code which it shares with other
    machines.

Remove this incomplete & broken R6000 CPU support in order to clean up
and in preparation for changes which will no longer need to consider
dragging the pretense of R6000 support along with them.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16236/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

We don't currently support the MT ASE for microMIPS kernels, and there
are no CPUs currently in existence that use both. They can however both
be enabled in Kconfig, resulting in build failures such as:

  AS      arch/mips/kernel/cps-vec.o
arch/mips/kernel/cps-vec.S: Assembler messages:
arch/mips/kernel/cps-vec.S:242: Warning: the 32-bit microMIPS architecture does not support the `mt' extension
arch/mips/kernel/cps-vec.S:276: Error: unrecognized opcode `mttc0 $13,$2,2'
arch/mips/kernel/cps-vec.S:282: Error: unrecognized opcode `mttc0 $8,$1,2'
arch/mips/kernel/cps-vec.S:285: Error: unrecognized opcode `mttc0 $0,$2,1'
...

Fix this by preventing MT from being enabled when targeting microMIPS.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16951/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

MIPS selects HAVE_SYSCALL_TRACEPOINTS twice. The first was added back in
v3.13 by commit 2d7bf993e073 ("MIPS: ftrace: Add support for syscall
tracepoints."), but then a second redundant one was added in v4.2 by
commit fb59e394 ("MIPS: ftrace: Enable support for syscall
tracepoints.").

Drop the duplicate select.

Fixes: fb59e394 ("MIPS: ftrace: Enable support for syscall tracepoints.")
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16654/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

CONFIG_MIPS_PGD_C0_CONTEXT, which allows a pointer to the page directory
to be stored in the cop0 Context register when enabled, was previously
only allowed for MIPSr2. MIPSr6 is just as able to make use of it, so
allow it there too.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16204/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Prior to MIPSr6 multithreading is only supported if CONFIG_MIPS_MT_SMP
is enabled, so CONFIG_MIPS_MT_SMP selects CONFIG_SYS_SUPPORTS_SCHED_SMT.
With MIPSr6 the CONFIG_MIPS_CPS SMP implementation always supports
multithreading, so have it select CONFIG_SYS_SUPPORTS_SCHED_SMT in order
to allow the scheduler to make better informed decisions on
multithreaded MIPSr6 systems (for example those using I6400 or I6500
CPUs).
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16195/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch switches MIPS to make use of generically implemented queued
spinlocks, rather than the ticket spinlocks used previously. This allows
us to drop a whole load of inline assembly, share more generic code, and
is also a performance win.

Results from running the AIM7 short workload on a MIPS Creator Ci40 (ie.
2 core 2 thread interAptiv CPU clocked at 546MHz) with v4.12-rc4
pistachio_defconfig, with ftrace disabled due to a current bug, and both
with & without use of queued rwlocks & spinlocks:

  Forks | v4.12-rc4 | +qlocks  | Change
 -------|-----------|----------|--------
     10 | 52630.32  | 53316.31 | +1.01%
     20 | 51777.80  | 52623.15 | +1.02%
     30 | 51645.92  | 52517.26 | +1.02%
     40 | 51634.88  | 52419.89 | +1.02%
     50 | 51506.75  | 52307.81 | +1.02%
     60 | 51500.74  | 52322.72 | +1.02%
     70 | 51434.81  | 52288.60 | +1.02%
     80 | 51423.22  | 52434.85 | +1.02%
     90 | 51428.65  | 52410.10 | +1.02%

The kernels used for these tests also had my "MIPS: Hardcode cpu_has_*
where known at compile time due to ISA" patch applied, which allows the
kernel_uses_llsc checks in cmpxchg() & xchg() to be optimised away at
compile time.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16358/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch switches MIPS to make use of generically implemented queued
read/write locks, rather than the custom implementation used previously.
This allows us to drop a whole load of inline assembly, share more
generic code, and is also a performance win.

Results from running the AIM7 short workload on a MIPS Creator Ci40 (ie.
2 core 2 thread interAptiv CPU clocked at 546MHz) with v4.12-rc4
pistachio_defconfig, with ftrace disabled due to a current bug, and both
with & without use of queued rwlocks & spinlocks:

  Forks | v4.12-rc4 | +qlocks  | Change
 -------|-----------|----------|--------
     10 | 52630.32  | 53316.31 | +1.01%
     20 | 51777.80  | 52623.15 | +1.02%
     30 | 51645.92  | 52517.26 | +1.02%
     40 | 51634.88  | 52419.89 | +1.02%
     50 | 51506.75  | 52307.81 | +1.02%
     60 | 51500.74  | 52322.72 | +1.02%
     70 | 51434.81  | 52288.60 | +1.02%
     80 | 51423.22  | 52434.85 | +1.02%
     90 | 51428.65  | 52410.10 | +1.02%

The kernels used for these tests also had my "MIPS: Hardcode cpu_has_*
where known at compile time due to ISA" patch applied, which allows the
kernel_uses_llsc checks in cmpxchg() & xchg() to be optimised away at
compile time.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16357/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since the eBPF machine has 64-bit registers, we only support this in
64-bit kernels.  As of the writing of this commit log test-bpf is showing:

  test_bpf: Summary: 316 PASSED, 0 FAILED, [308/308 JIT'ed]

All current test cases are successfully compiled.

Many examples in samples/bpf are usable, specifically tracex5 which
uses tail calls works.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16369/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Sort the entries in config MIPS alphabetically so as to make entries
easier to find.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16068/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

There is a pinctrl driver for each of the Ingenic SoCs supported by the
upstream Linux kernel. In order to switch away from the old GPIO
platform code, we now enable the pinctrl drivers by default for the
Ingenic SoCs.
Signed-off-by: NPaul Cercueil <paul@crapouillou.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

all architectures converted
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We declare CONFIG_ARCH_HAS_ILOG2_U32 & CONFIG_ARCH_HAS_ILOG2_U64 in
Kconfig, but they are always false since nothing ever selects them. The
generic fls-based implementation is efficient for MIPS anyway. Remove
the redundant Kconfig entries.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15840/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This the mips version of commit c1bd55f9 ("x86: opt into
HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit").

Simply use the tls system call argument instead of extracting the tls
argument by magic from the pt_regs structure.

See commit 3033f14a ("clone: support passing tls argument via C
rather than pt_regs magic") for more background.
Signed-off-by: NJames Cowgill <James.Cowgill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15855/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Some newer Loongson-3 have 64 bytes cache lines, so select
MIPS_L1_CACHE_SHIFT_6.
Signed-off-by: NHuacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J . Hill <Steven.Hill@caviumnetworks.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15755/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Some users must have 4K pages while needing a 48-bit VA space size.
The cleanest way do do this is to go to a 4-level page table for this
case.  Each page table level using order-0 pages adds 9 bits to the
VA size (at 4K pages, so for four levels we get 9 * 4 + 12 == 48-bits.

For the 4K page size case only we add support functions for the PUD
level of the page table tree, also the TLB exception handlers get an
extra level of tree walk.

[david.daney@cavium.com: Forward port to v4.10.]
[david.daney@cavium.com: Forward port to v4.11.]
Signed-off-by: NAlex Belits <alex.belits@cavium.com>
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Alex Belits <alex.belits@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15312/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add missing macros and methods that are required by
CONFIG_GENERIC_CPU_AUTOPROBE: MAX_CPU_FEATURES, cpu_have_feature(),
cpu_feature().

Also set a default elf platform as currently it is not set for most MIPS
platforms resulting in incorrectly specified modalias values in cpu
autoprobe ("cpu:type:(null):feature:...").

Export 'elf_hwcap' symbol so that it can be accessed from modules that
use module_cpu_feature_match()
Signed-off-by: NMarcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15395/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Octeon III has VZ ASE support, so allow KVM to be enabled on Octeon
CPUs as it should now be functional.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org

When a 32-bit kernel is configured to support MIPS64r6 (CPU_MIPS64_R6),
MIPS_O32_FP64_SUPPORT won't be selected as it should be because
MIPS32_O32 is disabled (o32 is already the default ABI available on
32-bit kernels).

This results in userland FP breakage as CP0_Status.FR is read-only 1
since r6 (when an FPU is present) so __enable_fpu() will fail to clear
FR. This causes the FPU emulator to get used which will incorrectly
emulate 32-bit FPU registers.

Force o32 fp64 support in this case by also selecting
MIPS_O32_FP64_SUPPORT from CPU_MIPS64_R6 if 32BIT.

Fixes: 4e9d324d ("MIPS: Require O32 FP64 support for MIPS64 with O32 compat")
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Reviewed-by: NPaul Burton <paul.burton@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.0.x-
Patchwork: https://patchwork.linux-mips.org/patch/15310/Signed-off-by: NJames Hogan <james.hogan@imgtec.com>

Turn on CPU_SUPPORTS_CPUFREQ and MIPS_EXTERNAL_TIMER for BMIPS.
Signed-off-by: NMarkus Mayer <mmayer@broadcom.com>
Acked-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Big endian CPUs require SWAP_IO_SPACE enabled to swap accesses to little
endian peripherals.

Without this patch, big endian kernels fail to communicate with little
endian periperals, such as PCI devices, on QEMU and FPGA based
platforms.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Fixes: eed0eabd ("MIPS: generic: Introduce generic DT-based board support")
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15105/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Kconfig entries are not aligned properly, so remove incorrect whitespace.
Signed-off-by: NMarcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14631/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch_mmap_rnd() uses hard-coded limits of 16MB for the randomisation
of mmap within 32bit processes and 256MB in 64bit processes. Since v4.4
other arches support tuning this value in /proc/sys/vm/mmap_rnd_bits.
Add support for this to MIPS.

Set the minimum(default) number of bits randomisation for 32bit to 8 -
which with 4k pagesize is unchanged from the current 16MB total
randomness. The minimum(default) for 64bit is 12bits, again with 4k
pagesize this is the same as the current 256MB.

This patch is necessary for MIPS32 to pass the Android CTS tests, with
the number of random bits set to 15.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Daniel Cashman <dcashman@android.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14617/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

There's no reason for the pre-r6 instruction emulation code to be
limited to uniprocessor kernels. We already emulate atomic memory access
instructions in a way that works for SMP systems, and nothing else
should be affected. Remove the artificial limitation, allowing pre-r6
instruction emulation to be used with SMP kernels.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14410/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch removes ARCH_WANT_OPTIONAL_GPIOLIB due to upstream changes.
Signed-off-by: NKelvin Cheung <keguang.zhang@gmail.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Cc: Yang Ling <gnaygnil@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13855/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IRQs from peripherals such as i2c/uart/ethernet come via
the AXI Interrupt controller.

Select it in Kconfig for xilfpga and add the DT node
Signed-off-by: NZubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14592/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch enables KASLR for Octeon systems. The SMP startup code is
such that the secondaries monitor the volatile variable
'octeon_processor_relocated_kernel_entry' for any non-zero value.
The 'plat_post_relocation hook' is used to set that value to the
kernel entry point of the relocated kernel. The secondary CPUs will
then jusmp to the new kernel, perform their initialization again
and begin waiting for the boot CPU to start them via the relocated
loop 'octeon_spin_wait_boot'. Inspired by Steven's code from Cavium.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: NSteven J. Hill <steven.hill@cavium.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14669/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since do_IRQ is now invoked on a separate IRQ stack, we select
HAVE_IRQ_EXIT_ON_IRQ_STACK so that softirq's may be invoked directly
from irq_exit(), rather than requiring do_softirq_own_stack.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Acked-by: NJason A. Donenfeld <jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14744/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Enable CONFIG_HARDENED_USERCOPY checks for MIPS, calling check_object
size in all of copy_{to,from}_user(), __copy_{to,from}_user() &
__copy_{to,from}_user_inatomic().
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14371/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This came to light when implementing native 64-bit atomics for ARCv2.

The atomic64 self-test code uses CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
to check whether atomic64_dec_if_positive() is available.  It seems it
was needed when not every arch defined it.  However as of current code
the Kconfig option seems needless

 - for CONFIG_GENERIC_ATOMIC64 it is auto-enabled in lib/Kconfig and a
   generic definition of API is present lib/atomic64.c
 - arches with native 64-bit atomics select it in arch/*/Kconfig and
   define the API in their headers

So I see no point in keeping the Kconfig option

Compile tested for:
 - blackfin (CONFIG_GENERIC_ATOMIC64)
 - x86 (!CONFIG_GENERIC_ATOMIC64)
 - ia64

Link: http://lkml.kernel.org/r/1473703083-8625-3-git-send-email-vgupta@synopsys.comSigned-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ming Lin <ming.l@ssi.samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert the MIPS SEAD-3 board support to be a generic board, supported
by generic kernels.

Because the SEAD-3 boot protocol was defined long ago and we don't want
to force a switch to the UHI protocol, SEAD-3 is added as a legacy board
which is detected by reading the REVISION register. This may technically
not be a valid memory read & future work will include attempting to
handle that gracefully. In practice since SEAD-3 is the only legacy
board supported by the generic kernel so far the read will only happen
on SEAD-3 boards, and even once Malta is converted the same REVISION
register exists there too. Other boards such as Boston, Ci20 & Ci40 will
use the UHI boot protocol & thus not run any of the legacy board detect
functions.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14354/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Introduce a "generic" platform, which aims to be board-agnostic by
making use of device trees passed by the boot protocol defined in the
MIPS UHI (Universal Hosting Interface) specification. Provision is made
for supporting boards which use a legacy boot protocol that can't be
changed, but adding support for such boards or any others is left to
followon patches.

Right now the built kernels expect to be loaded to 0x80100000, ie. in
kseg0. This is fine for the vast majority of MIPS platforms, but
nevertheless it would be good to remove this limitation in the future by
mapping the kernel via the TLB such that it can be loaded anywhere & map
itself appropriately.

Configuration is handled by dynamically generating configs using
scripts/kconfig/merge_config.sh, somewhat similar to the way powerpc
makes use of it. This allows for variations upon the configuration, eg.
differing architecture revisions or subsets of driver support for
differing boards, to be handled without having a large number of
defconfig files.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14353/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

On some MIPS systems, a subset of devices may have DMA coherent with CPU
caches. For example in systems including a MIPS I/O Coherence Unit
(IOCU), some devices may be connected to that IOCU whilst others are
not.

Prior to this patch, we have a plat_device_is_coherent() function but no
implementation which does anything besides return a global true or
false, optionally chosen at runtime. For devices such as those described
above this is insufficient.

Fix this by tracking DMA coherence on a per-device basis with a
dma_coherent field in struct dev_archdata. Setting this from
arch_setup_dma_ops() takes care of devices which set the dma-coherent
property via device tree, and any PCI devices beneath a bridge described
in DT, automatically.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14349/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Introduce support for PCI drivers using only functionality provided
generically by the PCI subsystem, by adding the minimum arch-provided
functions required.

The driver this has been developed for & tested with the xilinx-pcie on
a MIPS Boston development board.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14346/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Introduce 2 Kconfig symbols, CONFIG_PCI_DRIVERS_GENERIC &
CONFIG_PCI_DRIVERS_LEGACY, which indicate whether the system should be
built to for PCI drivers using the MIPS-specific struct pci_controller
API (hereafter "legacy" drivers) or more generic drivers using only
functionality provided by the PCI core (hereafter "generic" drivers).

The Kconfig entries are created such that platforms have to select
CONFIG_PCI_DRIVERS_GENERIC if they wish to use it - that is, the default
is CONFIG_PCI_DRIVERS_LEGACY so that existing platforms need no
modification.

The functions declared in pci.h are rearranged with those provided only
by pci-legacy.c being guarded by an #ifdef CONFIG_PCI_DRIVERS_LEGACY to
ensure they are only used in configurations where they are implemented.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14345/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Introduce support for CONFIG_PCI_DOMAINS_GENERIC, allowing for platforms
to make use of generic PCI domains instead of the MIPS-specific
implementation. The set_pci_need_domain_info function is introduced to
abstract away the removed need_domain_info field in struct
pci_controller, and pcibios_scanbus is adjusted to use the pci_domain_nr
accessor instead of directly accessing the index field.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14341/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>