As already demonstrated with PCI [1] and the platform bus [2], a
driver_override property in sysfs can be used to bypass the id
matching of a device to a AMBA driver. This can be used by VFIO to
bind to any AMBA device requested by the user.

[1] http://lists-archives.com/linux-kernel/28030441-pci-introduce-new-device-binding-path-using-pci_dev-driver_override.html
[2] https://www.redhat.com/archives/libvir-list/2014-April/msg00382.htmlSigned-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Reviewed-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

On qcom platforms we always enter the kernel in ARM mode,
regardless of the kernel being compiled for THUMB mode. Use
secondary_startup_arm() to properly switch the mode to what the
kernel expects if required.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Some platforms always enter the kernel in ARM mode even if the
kernel is compiled for THUMB2. Add a small wrapper on top of
secondary_startup() that switches into THUMB2 mode.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The __asmeq macro is used inside inline asm statements to ensure that
register asm variables that explicitly specify a register are mapped
correctly onto those registers when used in inline asm input and output
constraints. However, the string based matching fails to take into
account that 'fp' is often referred to as 'r11' and 'ip' is often
referred to as 'r12', (e.g., by clang), causing false negatives.

Fix this by making __asmeq consider the ("fp","r11"), ("r11","fp"),
("ip","r12") and ("r12","ip") cases specifically.
Reviewed-by: Alex Elder <elder@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The aurora_inv_range(), aurora_clean_range() and aurora_flush_range()
functions are highly redundant, both in source and in object code, and
they are harder to understand than necessary.

By moving the range loop into the aurora_pa_range() function, they
become trivial wrappers, and the object code start looking like what
one would expect for an optimal implementation.

Further optimization may be possible by using the per-CPU "virtual"
registers to avoid the spinlocks in most cases.

 (on Armada 370 RD and Armada XP GP, boot tested, plus a little bit of
 DMA traffic by reading data from a SD card)
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The aurora cache controller is the only remaining user of a couple
of functions in this file and are completely unused when that is
disabled, leading to build warnings:

arch/arm/mm/cache-l2x0.c:167:13: warning: 'l2x0_cache_sync' defined but not used [-Wunused-function]
arch/arm/mm/cache-l2x0.c:184:13: warning: 'l2x0_flush_all' defined but not used [-Wunused-function]
arch/arm/mm/cache-l2x0.c:194:13: warning: 'l2x0_disable' defined but not used [-Wunused-function]

With the knowledge that the code is now aurora-specific, we can
simplify it noticeably:

- The pl310 errata workarounds are not needed on aurora and can be removed
- As confirmed by Thomas Petazzoni from the data sheet, the cache_wait()
  macro is never needed.
- No need to hold the lock across atomic cache sync
- We can load the l2x0_base into a local variable across operations

There should be no functional change in this patch, but readability
and the generated object code improves, along with avoiding the
warnings.

 (on Armada 370 RD and Armada XP GP, boot tested, plus a little bit of
 DMA traffic by reading data from a SD card)
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Commit e1a5848e ("ARM: 7924/1: mm: don't bother with reserved ttbr0
when running with LPAE") removed the use of the reserved TTBR0 value
for LPAE systems, since the ASID is held in the TTBR and can be updated
atomicly with the pgd of the next mm.

Unfortunately, this patch forgot to update flush_context, which
deliberately avoids marking the local active ASID as allocated, since we
used to switch via ASID zero and didn't need to allocate the ASID of
the previous mm. The side-effect of this is that we can allocate the
same ASID to the next mm and, between flushing the local TLB and updating
TTBR0, we can perform speculative TLB fills for userspace nG mappings
using the page table of the previous mm.

The consequence of this is that the next mm can erroneously hit some
mappings of the previous mm. Note that this was made significantly
harder to hit by a391263c ("ARM: 8203/1: mm: try to re-use old ASID
assignments following a rollover") but is still theoretically possible.

This patch fixes the problem by removing the code from flush_context
that forces the allocated ASID to zero for the local CPU. Many thanks
to the Broadcom guys for tracking this one down.

Fixes: e1a5848e ("ARM: 7924/1: mm: don't bother with reserved ttbr0 when running with LPAE")

Cc: <stable@vger.kernel.org> # v3.14+
Reported-by: Raymond Ngun <rngun@broadcom.com>
Tested-by: Raymond Ngun <rngun@broadcom.com>
Reviewed-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

StrongARM core uses RCSR SMR bit to tell to bootloader that it was reset
by entering the sleep mode. After we have resumed, there is little point
in having that bit enabled. Moreover, if this bit is set before reboot,
the bootloader can become confused. Thus clear the SMR bit on resume
just before clearing the scratchpad (resume address) register.

Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Let kernel drivers to control wakeup sources instead of hardcoding them
in the collie.c board file.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Use handle_domain_irq instead of handle_IRQ to automatically map
hardware irq number to virq.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

As a part of driver consolidation, move GPIO-related IRQ code to
drivers/gpio/gpio-sa1100.c. The code does not use GPIOLIB_IRQCHIP (yet),
because sa1100 does not have a device for gpios, which is a requirement
for GPIOLIB_IRQCHIP. This will be the next step.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

As now both SC and GPIO irq domains start from 0 hwirq and do not
contain holes, switch to using irq_domain_add_simple() instead of
irq_domain_add_legacy().
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Now there is no difference between low and high GPIO irqdomains. Merge
them into single irqdomain handling all GPIOs.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Low GPIO pins use an interrupt in SC interrupts space. However it's
possible to handle them as if all the GPIO interrupts are instead tied
to single GPIO handler, which later decodes GEDR register and
chain-calls next IRQ handler. So split first 11 interrupts into system
part (IRQ_GPIO0_SC - IRQ_GPIO10_SC) which work exactly like the rest of
system controller interrupts and real GPIO interrupts
(IRQ_GPIO0..IRQ_GPIO10). A single handler sa1100_gpio_handler then
decodes and calls next handler.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The recently added ARM_KERNMEM_PERMS feature works by manipulating
the kernel page tables, which obviously requires an MMU. Trying
to enable this feature when the MMU is disabled results in a lot
of compile errors in mm/init.c, so let's add a Kconfig dependency
to avoid that case.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Minimal builds for v7M are broken when printk is disabled. The caller is
assembly so add the necessary ifdef around the call.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

There is currently a hardcoded limit of 64KB for the DTB to live in and
be extended with ATAG info.  Some DTBs have outgrown that limit:

$ du -b arch/arm/boot/dts/omap3-n900.dtb
70212   arch/arm/boot/dts/omap3-n900.dtb

Furthermore, the actual size passed to atags_to_fdt() included the stack
size which is obviously wrong.

The initial DTB size is known, so use it to size the allocated workspace
with a 50% growth assumption and relocate the temporary stack above that.
This is also clamped to 32KB min / 1MB max for robustness against bad
DTB data.
Reported-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

When tearing down the DMA ops for a device via of_dma_deconfigure, we
unconditionally detach the device from its IOMMU domain. For devices
that aren't actually behind an IOMMU, this produces a "Not attached"
warning message on the console.

This patch changes the teardown code so that we don't detach from the
IOMMU domain when there isn't an IOMMU dma mapping to start with.
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This line converts PHYS_OFFSET into PHYS_PFN_OFFSET.
It is better to use PAGE_SHIFT rather than the magic number 12.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This comment does not correspond to the actual code.

When zImage is loaded at a lower *OR* higher address of
the destination of Image, it won't overwrite itself.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

DMA contiguous allocations have been able to use highmem since commit
"95b0e655 ARM: mm: don't limit default CMA region only to low memory"
but a comment still notes the earlier "low memory" limitation.  Update
the comment to remove the low memory limitation and fix the
s/contigouos/contiguous/ typo while we're at it.
Signed-off-by: George G. Davis <george_davis@mentor.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

As of commit abda1bd5 __cpu_suspend()
takes only 2 arguments, and those arguments are passed by the platform
code. This comment thus makes no sense, as cpu_suspend() is not actually
hiding any arguments.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The current rounding of "size" is wrong:

 - If "start" is sufficiently near the next page boundary, "size"
   is decremented by more than enough and the last page is lost.

 - If "size" is sufficiently small, it is wrapped around and gets
   a bogus value.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

When building a multi_v7_defconfig kernel it is not possible to configure
DEBUG_LL to use any serial device except a ARM Primecell PL01X, or more
accurately and worse, it is possible to configure a different serial
device but KConfig does not honour this request. In fact this also
overrides the user selection for some of the single platform kernels, for
example I don't think DEBUG_LL can be targeted at ICE or semihosted
supervisor for ARCH_VERSATILE.

This happens because DEBUG_UART_PL01X is automatically enabled by
some architectures and this means user decisions made regarding
the DEBUG_LL backend will be overridden. Problem is fixed by removing the
automatic enabling of this option.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

On EP93XX uncompress.h uses CONFIG_DEBUG_UART_PHYS instead of a hard
coded serial port. This means the build breaks when DEBUG_LL
(and DEBUG_LL_UART_PL01X) is not enabled.

This is fixed by adding a new dependency.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

As part of the migration we introduce DEBUG_UART_PHYS/DEBUG_UART_VIRT
which default to UART1 but allow a user to configure UART2 or UART3.
We also introduce symbolic names for the registers and flags.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The omap1's debug-macro.S is similar to the generic 8250 code. Compared to
the 8520 code the omap1 macro automatically determines what UART to use
based on breadcrumbs left by the bootloader and automatically copes with
the eccentric register layout on OMAP7XX.

This patch drops both these features and relies instead on the generic
8250 macros:

1. Dropping support for the bootloader breadcrumbs is identical to the
   way the migration was handled for OMAP2 (see 808b7e07...).

2. Support for OMAP7XX still exists but it must be configured by hand
   (DEBUG_OMAP7XXUART1/2/3) rather than handled at runtime.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: linux-omap@vger.kernel.org
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

As part of the migration a couple of uart definitions have been copied
from of the platform specific header files.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Only a very small handful of platforms support DEBUG_LL_UART_NONE but it
lurks in the menus of every single platform config ready to break the
build. This is an especial problem for defconfig/oldconfig since it is
often selected by default.

This patch solves the problem by removing this option. Any platforms
still depending upon this option must be migrated.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

All defconfigs touched by this patch already enable DEBUG_LL and by
default DEBUG_LL_UART_NONE will be selected. This causes no issues
today because due to some back compatibility magic we eventually need
to remove it is not actually honoured. Nevertheless DEBUG_LL_UART_8250
is the right value for these platforms and should be set in the config
files.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The default value for DEBUG_CNS3xxx appears twice. This patch removes
the one with the wrong sort order.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Replace the amba_pclk_enable and amba_pclk_disable macros with static
inline functions and remove checks for IS_ERR. The amba bus clock won't
be ERR because probe would fail before the use of these functions.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This code was restored with commit 080fc66f ("ARM: Bring back ARMv3 IO
and user access code") because the RiscPC memory bus does not understand
half-word load/stores.  However only the IO code needed restoring since
the alternative user access code contains no half-word accesses, is
already used when CONFIG_PREEMPT is set and runs faster on a StrongARM.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This patch adds device tree nodes for L2 cache controller present on
Exynos4 SoCs.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

On Exynos SoCs it is necessary to resume operation of L2C early in
assembly code, because otherwise certain systems will crash. This patch
adds necessary code to non-secure resume handler.

[rewrote the code accessing l2x0_saved_regs]
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Exynos4 SoCs equipped with an L2C-310 cache controller and running under
secure firmware require certain registers of aforementioned IP to be
accessed only from secure mode. This means that SMC calls are required
for certain register writes. To handle this, an implementation of
.write_sec and .configure callbacks is provided by this patch.

[added comment and reworked unconditional call to SMC_CMD_L2X0INVALL]
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Firmware on certain boards (e.g. ODROID-U3) can leave incorrect L2C prefetch
settings configured in registers leading to crashes if L2C is enabled
without overriding them. This patch introduces bindings to enable
prefetch settings to be specified from DT and necessary support in the
driver.

[mszyprow: rebased onto v3.18-rc1, added error message when prefetch related
 dt property has been provided without any value]
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Certain platforms (i.e. Exynos) might need to set .write_sec callback
from firmware initialization which is happenning in .init_early callback
of machine descriptor. However current code will overwrite the pointer
with whatever is present in machine descriptor, even though it can be
already set earlier. This patch fixes this by making the assignment
conditional, depending on whether current .write_sec callback is NULL.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Because certain secure hypervisor do not allow writes to individual L2C
registers, but rather expect set of parameters to be passed as argument
to secure monitor calls, there is a need to provide an interface for the
L2C driver to ask the firmware to configure the hardware according to
specified parameters. This patch adds such.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>