This should have been part of 40e084a5

 ('MIPS: Add uprobes support.').

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fixes: 40e084a5

 ("MIPS: Add uprobes support.")
Acked-by: Jonathan Corbet <corbet@lwn.net>
Cc: linux-mips@linux-mips.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14392/


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

Currently regs_return_value always negates reg[2] if it determines
the syscall has failed, but when called in kernel context this check is
invalid and may result in returning a wrong value.

This fixes errors reported by CONFIG_KPROBES_SANITY_TEST

Fixes: d7e7528b

 ("Audit: push audit success and retcode into arch ptrace.h")
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.3+
Patchwork: https://patchwork.linux-mips.org/patch/14381/


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

The aflags-vdso is based on ccflags-vdso, which already contains the -I*
and -EL/-EB flags from KBUILD_CFLAGS, but those flags are needlessly
added again to aflags-vdso.

Drop the duplication.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reported-by: Maciej W. Rozycki <macro@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14369/


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

The native ABI vDSO linker script vdso.lds is built by preprocessing
vdso.lds.S, with the native -mabi flag passed in to get the correct ABI
definitions. Unfortunately however certain toolchains choke on -mabi=64
without a corresponding compatible -march flag, for example:

cc1: error: ‘-march=mips32r2’ is not compatible with the selected ABI
scripts/Makefile.build:338: recipe for target 'arch/mips/vdso/vdso.lds' failed

Fix this by including ccflags-vdso in the KBUILD_CPPFLAGS for vdso.lds,
which includes the appropriate -march flag.

Fixes: ebb5e78c

 ("MIPS: Initial implementation of a VDSO")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 4.4.x-
Patchwork: https://patchwork.linux-mips.org/patch/14368/


Signed-off-by: Ralf 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: Paul 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: Ralf Baechle <ralf@linux-mips.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: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14354/


Signed-off-by: Ralf 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: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14353/


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

Add support for generating kernel images in the Flattened Image Tree
(.itb) format as supported by U-Boot. This format is essentially a
Flattened Device Tree binary containing images (kernels, DTBs, ramdisks)
and configurations which link those images together. The big advantages
of FIT images over the uImage format are:

  - We can include FDTs in the kernel image in a way that the bootloader
    can extract it & manipulate it before providing it to the kernel.
    Thus we can ship FDTs as part of the kernel giving us the advantages
    of being able to develop & maintain the DT within the kernel tree,
    but also have the benefits of the bootloader being able to
    manipulate the FDT. Example uses for this would be to inject the
    kernel command line into the chosen node, or to fill in the correct
    memory size.

  - We can include multiple configurations in a single kernel image.
    This means that a single FIT image can, given appropriate
    bootloaders, be booted on different boards with the bootloader
    selecting an appropriate configuration & providing the correct FDT
    to the kernel.

  - We can support a multitude of hashes over the data.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14352/


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

On MIPS64 we define the default CAC_BASE as one of the xkphys regions of
the virtual address space. Since the CCA is encoded in bits 61:59 of
xkphys addresses, fixing CAC_BASE to any particular one prevents us from
dynamically changing the CCA as we do for MIPS32 where CAC_BASE is
placed within kseg0. In order to make the kernel more generic, drop the
current kludge that gives CAC_BASE CCA=3 if CONFIG_DMA_NONCOHERENT is
selected (disregarding CONFIG_DMA_MAYBE_COHERENT) & CCA=5 (which is not
standardised by the architecture) otherwise. Instead read Config.K0 and
generate the appropriate offset into xkphys, presuming that either the
bootloader or early kernel code will have configured Config.K0
appropriately. This seems like the best option for a generic
implementation.

The ip27 spaces.h is adjusted to set its former value of CAC_BASE, since
it's the only user of CAC_BASE from assembly (in its smp_slave_setup
macro). This allows the generic case to focus solely on C code without
breaking ip27.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14351/


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

If a bus error occurs on a system with a MIPS Coherence Manager (CM)
then the CM may hold useful diagnostic information. Printing this out
has so far been left up to boards, with the requirement that they
register a board_be_handler function & call mips_cm_error_decode() from
there.

In order to avoid boards other than Malta needing to duplicate this
code, call mips_cm_error_decode() automatically if the board registers
no board_be_handler, and remove the Malta implementation of that.

This patch results in no functional change, but removes a further piece
of platform-specific code.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14350/


Signed-off-by: Ralf 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: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14349/


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

There are no cases where plat_device_is_coherent() will return zero
whilst hw_coherentio is non-zero, and acting any differently in such a
case doesn't make much sense - if a device is non-coherent with the CPU
caches then access to memory "coherent" with DMA must be uncached. Clean
up the nonsensical case.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14348/


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

The coherentio variable has previously been used as a boolean value,
indicating whether the user specified that coherent I/O should be
enabled or disabled. It failed to take into account the case where the
user does not specify any preference, in which case it makes sense that
we should default to coherent I/O if the hardware supports it
(hw_coherentio is non-zero).

Introduce an enum to clarify the 3 different values of coherentio & use
it throughout the code, modifying plat_device_is_coherent() &
r4k_cache_init() to take into account the default case.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Paul Burton <paul.burton@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/14347/


Signed-off-by: Ralf 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: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14346/


Signed-off-by: Ralf 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: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14345/


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

Split out the parts of pci.c that are used by existing systems with
MIPS-style PCI drivers but that will not be used by systems with more
generic PCI drivers such as pcie-xilinx. This is done in preparation for
allowing configurations where the code moved to pci-legacy.c is not
built.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Paul Burton <paul.burton@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/14344/


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

The MIPS implementation of pcibios_assign_all_busses trivially returns
1. Implement it as a static function in asm/pci.h such that the compiler
can inline it & optimise out never-taken paths.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14343/


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

In preparation for allowing configurations in which pcibios_init is not
included, make pcibios_set_cache_line_size an initcall. arch_initcall is
used such that it runs before the pcibios_init subsys_initcall for
platforms that continue to use it.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14342/


Signed-off-by: Ralf 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: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14341/


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

Rather than open-coding a linked list implementation, make use of the
one in linux/list.h.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14340/


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

Current instruction decoder for uprobe/kprobe handler only handles
branches with delay slots. For compact branches the behaviour is rather
unpredictable - and depending on the encoding of a compact branch
instruction may result in one (or more) of:
- executing an instruction that follows a branch which wasn't in a delay
  slot and shouldn't have been executed
- incorrectly emulating a branch leading to a jump to a wrong location
- unexpected branching out of the single-stepped code and never reaching
  the breakpoint that should terminate the probe handler

Results of these actions are generally unpredictable, but can end up
with a probed application or kernel crash, so disable placing probes on
compact branches until they are handled properly.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14336/


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

Currently both kprobes and uprobes code have definitions of the
insn_has_delay_slot method. Move it to a separate header as an inline
method that each probe-specific method can later use.
No functional change intended, although the methods slightly varied in
the constraints they set for the methods - the uprobes one was chosen as
it is slightly more specific when filtering opcode fields.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14335/


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

Use appended DTB when available.

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14337/


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

Changes node names of the interrupt-controller device nodes to
interrupt-controller instead of label strings.

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jonas Gorski <jonas.gorski@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: MIPS Mailing List <linux-mips@linux-mips.org>
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14004/


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

Adds NAND device nodes to BCM7xxx MIPS based SoCs.

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jonas Gorski <jonas.gorski@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: MIPS Mailing List <linux-mips@linux-mips.org>
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14003/


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

Adds SDHCI device nodes to BCM7xxx MIPS based SoCs.

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jonas Gorski <jonas.gorski@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: MIPS Mailing List <linux-mips@linux-mips.org>
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14002/


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

Adds GPIO device nodes to BCM7xxx MIPS based SoCs.

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jonas Gorski <jonas.gorski@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: MIPS Mailing List <linux-mips@linux-mips.org>
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14001/


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

Adds PWM device nodes to BCM7xxx MIPS based SoCs.

Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Jonas Gorski <jonas.gorski@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: MIPS Mailing List <linux-mips@linux-mips.org>
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14000/


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

The arch code will hang the machine with an infinite loop if the board
doesn't provide an impelementation of halt - let it, rather than
duplicating it.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14280/


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

Make use of the generic syscon-reboot driver to reboot the Malta board,
reducing the amount of platform code it requires.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Stephan Linz <linz@li-pro.net>
Cc: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14279/


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

Add the DT nodes required to probe the CFI compatible parallel monitor
flash found on the Malta development board, and remove the platform
code that was previously doing it. Delete the now-empty malta-platform.c
file. Adjust the Malta defconfigs that enable MTD & the pflash/CFI
driver to enable CONFIG_MTD_PHYSMAP_OF rather than CONFIG_MTD_PHYSMAP in
order to preserve their behaviour.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14278/


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

Add the DT node required to probe the RTC, and remove the platform code
that was previously doing it.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14277/


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

Since commit 44a7185c

 ("of/platform: Add common method to populate
default bus") the Malta publish_devices initcall has essentially been a
no-op. Remove it.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14276/


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

Since commit 44a7185c

 ("of/platform: Add common method to populate
default bus") platforms calling of_platform_bus_probe from an initcall
is either a rather unsafe race with of_platform_default_populate_init or
a no-op. The MIPS Malta board needs to probe devices under an ISA bus,
which we do support in the of_busses array but until now haven't
included in of_default_bus_match_table.

Add an "isa" entry to of_default_bus_match_table such that we can just
accept use of of_platform_default_populate_init & remove the
Malta-specific match table in a later patch.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14275/


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

Probe the CPU, GIC & i8259 interrupt controllers present in the Malta
system using device tree. This enables interrupts to be provided to
devices using device tree as they are moved over to being probed using
it.

Since Malta is very configurable it's unknown whether a GIC will be
present at compile time. In order to support both cases the
malta_dt_shim code is added in order to detect whether a GIC is present,
adjusting the DT to route interrupts correctly and nop out the GIC node
if no GIC is found.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14274/


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

Malta boards can have more than 256MB DDR available, but we have
previously only made use of up to 256MB (ie. the DDR accessible via
kseg0) by default, without the user manually specifying mem= kernel
parameters. This patch causes all available DDR, as reported by the
bootloader via the ememsize or memsize environment variables or
optionally on the command line, to be used when possible without the
user needing to manually provide the memory ranges.

Malta now has 2 subtly different memory maps which have to be taken into
account when setting this up. The original memory map (referred to by
the code as v1) has up to 2GB of DDR aliased in both the upper & lower
halves of the 32 bit physical address space, with a 256MB I/O region
obscuring 0x10000000-0x1fffffff only in the lower alias. The revised v2
memory map is flat with up to 4GB DDR starting from 0x0, and the I/O
region obscures 256MB of DDR which becomes inacessible. The memory map
in use is indicated by a register provided by the rocit2 system
controller, which is checked in order to set up the kernels memory
ranges accordingly.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14273/


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

Set the PCI_BAR0 register in all configurations such that PCI devices
can perform DMA to all of the bottom 2GB of the physical address space.
This is imperfect if we make use of the legacy Malta memory map, but it
is an improvement on the inconsistent values setup before.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14272/


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

The i8259A_irq_pending function is unused. Remove the dead code.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14271/


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

The default i8259 polling function (i8259_irq) is nicely generic but is
fairly costly. Platforms often provide an alternative means of polling
for an i8259 interrupt, and when using the i8259 without device tree
have typically just chained its parent interrupt to their own handler
function. In order to allow for platform-specific polling functions to
be used in cases where the driver is probed via device tree, provide an
i8259_set_poll function that accepts a pointer to an alternative poll
function that will override the default.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14270/


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

Mapping the parent IRQ will use a virq number which may conflict with
the hardcoded I8259A_IRQ_BASE..I8259A_IRQ_BASE+15 range that the i8259
driver expects to be free. If this occurs then we'll hit errors when
adding the i8259 IRQ domain, since one of its virq numbers will already
be in use.

Avoid this by adding the i8259 domain before mapping the parent IRQ,
such that the i8259 virq numbers become used before the parent interrupt
controller gets a chance to use any of them.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14269/


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