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>

The SEAD3 board defines a custom implementation of read_persistent_clock
which does exactly the same dummy operation as the generic weak version.
Remove the not really implemented custom version.

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/14064/


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

Probe the img-ascii-lcd driver using device tree in order to display a
message on the SEAD3 board's LCD display, and remove the platform code
that was formerly performing this function. This removes more platform
code and moves SEAD3 further towards being entirely DT-based.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jacek Anaszewski <j.anaszewski@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/14063/


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

Add a driver for simple ASCII LCD displays found on the MIPS Boston,
Malta & SEAD3 development boards. The Boston display is an independent
memory mapped device with a simple memory mapped 8 byte register space
containing the 8 ASCII characters to display. The Malta display is
exposed as part of the Malta board registers, and provides 8 registers
each of which corresponds to one of the ASCII characters to display. The
SEAD3 display is slightly more complex, exposing an interface to an
S6A0069 LCD controller via registers provided by the boards CPLD.
However although the displays differ in their register interface, we
require similar functionality on each board so abstracting away the
differences within a single driver allows us to share a significant
amount of code & ensure consistent behaviour.

The driver displays the Linux kernel version as the default message, but
allows the message to be changed via a character device. Messages longer
then the number of characters that the display can show will scroll.

This provides different behaviour to the existing LCD display code for
the MIPS Malta or MIPS SEAD3 platforms in the following ways:

  - The default string to display is not "LINUX ON MALTA" or "LINUX ON
    SEAD3" but "Linux" followed by the version number of the kernel
    (UTS_RELEASE).

  - Since that string tends to be significantly longer it scrolls twice
    as fast, moving every 500ms rather than every 1s.

  - The LCD won't be updated until the driver is probed, so it doesn't
    provide the early "LINUX" string.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.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/14062/


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

Add documentation for a devicetree binding for the simple ASCII LCD
displays found on development boards such as the MIPS Boston, MIPS Malta
& MIPS SEAD3 from Imagination Technologies.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14061/


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

The SEAD3 board no longer uses the cobalt_lcdfb driver, so remove the
SEAD3-specific code from it.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Ondrej Zary <linux@rainbow-software.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Simon Horman <horms+renesas@verge.net.au>
Cc: linux-mips@linux-mips.org
Cc: linux-fbdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14060/


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

The 2 line * 16 character LCD display on the SEAD3 board has no real use
as a framebuffer device. It's far too small to produce any meaningful
output if used as the kernel console, SEAD3 is a development board that
will essentially always have a far more useful UART connection & the
code in sead3-display.c will overwrite whatever's on the display every
second anyway. Remove this unused code.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14059/


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

Parse the memsize argument provided by the bootloader in the DT shim
code, allowing the user to override it on the command line. This places
all of the DT manipulation code into sead3-dtshim.c.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14058/


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

Remove the custom platform code to restart when instructed to power off,
instead relying upon the generic restart-poweroff driver probed via DT
to do the same thing.

Remove also the halt implementation, which is incorrect. The generic
MIPS version will hang the system as halt should.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jacek Anaszewski <j.anaszewski@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/14057/


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

Remove the SEAD3 implementation of _machine_restart & instead make use
of the generic syscon-reboot driver probed via device tree.

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/14056/


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

Probe a driver for the PLED & FLED LEDs found on the SEAD3 board using
the register-bit-led driver via device tree, rather than a custom driver
via platform code. Enable support for the register-bit-led driver & its
prerequisite syscon in sead3_defconfig.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jacek Anaszewski <j.anaszewski@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/14054/


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

Probe the system parallel flash using device tree rather than platform
code, in order to reduce the amount of the latter.

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/14053/


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

The SEAD-3 board is now probing its EHCI controller using the generic
EHCI driver & its generic-ehci device tree binding. Remove the unused
SEAD-3 specific EHCI code.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14052/


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

Probe the SEAD3 EHCI controller using the generic-ehci driver & device
tree rather than platform code, in order to reduce the amount of the
latter.

Now that no devices probed from platform code require interrupts, remove
the retrieval of the IRQ domain & sead3int.h.

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/14051/


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

Probe the smsc911x ethernet controller using device tree rather than
platform code, reducing the amount of the latter.

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/14050/


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

Stop selecting SYS_HAS_EARLY_PRINTK & remove the custom support for
early output to the ns16550a UARTs, instead relying upon generic
ns16550a earlycon support. This reduces the amount of platform code
required for SEAD3 without losing any functionality.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14049/


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

Probe the UARTs on SEAD3 boards using device tree rather than platform
code, in order to reduce the amount of the latter. This requires that
CONFIG_SERIAL_OF_PLATFORM be enabled, so enable it in sead3_defconfig.
The SEAD3 DT shim code is extended to read bootloader environment
variables to determine the appropriate UART & mode for kernel console
output & set the stdout-path property of the chosen node accordingly.

In contrast to the old platform code, which appears to have only ever
set "console=ttyS0,38400n8r" with the code in console_config never
having an effect, this will honor the "yamontty" environment variable to
select between the 2 UARTs on the board and then check the "modetty0" or
"modetty1" variable as appropriate to determine the UART configuration.

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/14048/


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

Probe the CPU interrupt controller & optional Global Interrupt
Controller (GIC) using devicetree rather than platform code. Because the
bootloader on SEAD3 does not provide a device tree to the kernel & the
device tree is always built in, we patch out the GIC node during boot if
we detect that a GIC is not present in the system.

The appropriate IRQ domain is discovered by platform code setting up
device IRQ numbers temporarily. It will be removed by further patches
which move the devices towards being probed via device tree.

No behavioural change is intended by this patch.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Jacek Anaszewski <j.anaszewski@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/14047/


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

Split the obj-y entries for SEAD3 onto a line each, so that they're more
independent & can be modified more clearly by later commits.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14046/


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

The MIPS Coherent Processing System (CPS) power management code has
previously generated code used to enter low power idle states once
during boot for all CPUs. This has the drawback that if a CPU is present
in the system but not being used (for example due to the maxcpus kernel
parameter) then we encounter problems due to not having probed that CPU
for information about its type & properties. The result of this is that
we generate entry code which is both unused, potentially entirely
invalid & likely to be unsuitable for the CPU in question anyway.

Avoid this by generating idle state entry code only when a CPU is
brought online. This way we only ever generate code for CPUs that we
know we've probed the properties of, and that will actually be used.

[ralf@linux-mips.org: Resolve merge conflict.]

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14259/


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

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  In the case of
kvm where it is modular, we can extend that to also include files
that are building basic support functionality but not related
to loading or registering the final module; such files also have
no need whatsoever for module.h

The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each instance for the
presence of either and replace as needed.  In this case, we did
not need to add either to any files.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14036/


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

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.

We also needed to remove the no-op MODULE_DEVICE_TABLE usage in
several instances to permit removal of the module.h include.  The
files in these instances were all controlled by bool Kconfig.

In one instance, module_param was being used so we transition the
module.h include onto a moduleparam.h include.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14035/


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

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.

The compiler.h additions are for an implict presence of the
"notrace" which module.h brought in but export.h does not.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14034/


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

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14033/


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

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.

In the case of the n32/o32 files, we have to get rid of a couple
no-op MODULE_ tags to facilitate the module.h removal.  They piggy
back off the fs/ elf binary support, which is also a bool Kconfig.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14032/


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

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

For the MIPS remote processor implementation, we need additional IPIs to
talk to the remote processor. Since MIPS GIC reserves exactly the right
number of IPI IRQs required by Linux for the number of VPs in the
system, this is not possible without releasing some recources.

This commit introduces mips_smp_ipi_allocate() which allocates IPIs to a
given cpumask. It is called as normal with the cpu_possible_mask at
bootup to initialise IPIs to all CPUs. mips_smp_ipi_free() may then be
used to free IPIs to a subset of those CPUs so that their hardware
resources can be reused.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Lisa Parratt <Lisa.Parratt@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-remoteproc@vger.kernel.org
Cc: lisa.parratt@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14285/


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

When adding a wired entry to the TLB via add_wired_entry, the tlb is
flushed with local_flush_tlb_all, which on CPUs with TLBINV results in
the new wired entry being flushed again.

Behavior of the TLBINV instruction applies to all applicable TLB entries
and is unaffected by the setting of the Wired register. Therefore if
the TLB has any wired entries, fall back to iterating over the entries
rather than blasting them all using TLBINVF.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: lisa.parratt@imgtec.com
Cc: Hugh Dickins <hughd@google.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-remoteproc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14283/


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

flush_icache_range() flushes icache lines in a protected fashion for
kernel addresses, however this isn't correct with EVA where protected
cache ops only operate on user addresses, making flush_icache_range()
ineffective.

Split the implementations of __flush_icache_user_range() from
flush_icache_range(), changing the normal flush_icache_range() to use
unprotected normal cache ops.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14156/


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

Convert KVM dynamic translation of guest instructions to flush icache
for guest mapped addresses using the new
__local_flush_icache_user_range() API to allow the more generic
flush_icache_range() to be changed to work on kernel addresses only.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14155/


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

Update arch_uprobe_copy_ixol() to use the kmap_atomic() based kernel
address to flush the icache with flush_icache_range(), rather than the
user mapping. We have the kernel mapping available anyway and this
avoids having to switch to using the new __flush_icache_user_range() for
the sake of Enhanced Virtual Addressing (EVA) where flush_icache_range()
will become ineffective on user addresses.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14154/
Patchwork: https://patchwork.linux-mips.org/patch/14308/


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

The cacheflush(2) system call uses flush_icache_range() to flush a range
of usermode addresses from the icache, so change it to utilise the new
__flush_icache_user_range() API to allow the more generic
flush_icache_range() to be changed to work on kernel addresses only.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14153/


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

flush_icache_range() is used for both user addresses (i.e.
cacheflush(2)), and kernel addresses (as the API documentation
describes).

This isn't really suitable however for Enhanced Virtual Addressing (EVA)
where cache operations on usermode addresses must use a different
instruction, and the protected cache ops assume user addresses, making
flush_icache_range() ineffective on kernel addresses.

Split out a new __flush_icache_user_range() and
__local_flush_icache_user_range() for users which actually want to flush
usermode addresses (note that flush_icache_user_range() already exists
on various architectures but with different arguments).

The implementation of flush_icache_range() will be changed in an
upcoming commit to use unprotected normal cache ops so as to always work
on the kernel mode address space.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14152/


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

The EVA conditional bc_wback_inv() at the end of flush_icache_range() to
flush the modified code all the way back to RAM was apparently there for
debug purposes and to accommodate the Malta EVA configuration which
makes use of a physical alias, and didn't use the CP0_EBase.WG (Write
Gate) bit to put the exception vector in the same physical alias where
the exception vector code is written and is being flushed.

Now that CP0_EBase.WG is used, lets drop this flush.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14151/


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

On CPUs which support the EBase WG (write gate) flag, the most
significant bits of the exception base can be changed. Firmware running
on a VP(E) using MIPS rproc may change EBase to point into the user
segment where the firmware is located such that it can service
interrupts. When control is transferred back to the kernel the EBase
must be switched back into the kernel segment, such that the kernel's
exception vectors are used.

Similarly when vectored interrupts (vint) or vectored external interrupt
controllers (veic) are enabled an exception vector is allocated from
bootmem, and written to the EBase register. Due to the WG flag being
clear, only bits 29:12 will be written. Asside from the rproc case above
this is normally fine (as it will usually be a low allocation within the
KSeg0 range, however when Enhanced Virtual Addressing (EVA) is enabled
the allocation may be outside of the traditional KSeg0/KSeg1 address
range, resulting in the wrong EBase being written.

Correct both cases (configure_exception_vector() for the boot CPU, and
per_cpu_trap_init() for secondary CPUs) to write EBase with the WG flag
first if supported.

On the Malta EVA configuration, KSeg0 is mapped to physical address 0,
and memory is allocated from the KUSeg segment which is mapped to
physical address 0x80000000, which physically aliases the RAM at 0. This
only worked due to the exception base address aliasing the same
underlying RAM that was written to & cache flushed, and due to
flush_icache_range() going beyond the call of duty and flushing from the
L2 cache too (due to the differing physical addresses).

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14150/


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