ARMv8 cores have the exact same timer as ARMv7 cores. Make sure the
KVM timer code can match it in the device tree.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit f61701e0a2)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
The HYP mode world switch in all its glory.
Implements save/restore of host/guest registers, EL2 trapping,
IPA resolution, and additional services (tlb invalidation).
Reviewed-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 55c7401d92)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Provide EL2 with page tables and stack, and set the vectors
to point to the full blown world-switch code.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 092bd143cb)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Add the necessary infrastructure for identity-mapped HYP page
tables. Idmap-ed code must be in the ".hyp.idmap.text" linker
section.
The rest of the HYP ends up in ".hyp.text".
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 2240bbb697)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
To use the virtual counters from the host, we need to ensure that
CNTVOFF doesn't change unexpectedly. When we change to a guest, we
replace the host's CNTVOFF, but we don't restore it when returning to
the host.
As the host sets CNTVOFF to zero, and never changes it, we can simply
zero CNTVOFF when returning to the host. This patch adds said zeroing to
the return to host path.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Christoffer Dall <cdall@cs.columbia.edu>
(cherry picked from commit f793c23ebb)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
As KVM/arm64 is looming on the horizon, it makes sense to move some
of the common code to a single location in order to reduce duplication.
The code could live anywhere. Actually, most of KVM is already built
with a bunch of ugly ../../.. hacks in the various Makefiles, so we're
not exactly talking about style here. But maybe it is time to start
moving into a less ugly direction.
The include files must be in a "public" location, as they are accessed
from non-KVM files (arch/arm/kernel/asm-offsets.c).
For this purpose, introduce two new locations:
- virt/kvm/arm/ : x86 and ia64 already share the ioapic code in
virt/kvm, so this could be seen as a (very ugly) precedent.
- include/kvm/ : there is already an include/xen, and while the
intent is slightly different, this seems as good a location as
any
Eventually, we should probably have independant Makefiles at every
levels (just like everywhere else in the kernel), but this is just
the first step.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
(cherry picked from commit 7275acdfe2)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Linux requires a number of atomic operations to provide full barrier
semantics, that is no memory accesses after the operation can be
observed before any accesses up to and including the operation in
program order.
On arm64, these operations have been incorrectly implemented as follows:
// A, B, C are independent memory locations
<Access [A]>
// atomic_op (B)
1: ldaxr x0, [B] // Exclusive load with acquire
<op(B)>
stlxr w1, x0, [B] // Exclusive store with release
cbnz w1, 1b
<Access [C]>
The assumption here being that two half barriers are equivalent to a
full barrier, so the only permitted ordering would be A -> B -> C
(where B is the atomic operation involving both a load and a store).
Unfortunately, this is not the case by the letter of the architecture
and, in fact, the accesses to A and C are permitted to pass their
nearest half barrier resulting in orderings such as Bl -> A -> C -> Bs
or Bl -> C -> A -> Bs (where Bl is the load-acquire on B and Bs is the
store-release on B). This is a clear violation of the full barrier
requirement.
The simple way to fix this is to implement the same algorithm as ARMv7
using explicit barriers:
<Access [A]>
// atomic_op (B)
dmb ish // Full barrier
1: ldxr x0, [B] // Exclusive load
<op(B)>
stxr w1, x0, [B] // Exclusive store
cbnz w1, 1b
dmb ish // Full barrier
<Access [C]>
but this has the undesirable effect of introducing *two* full barrier
instructions. A better approach is actually the following, non-intuitive
sequence:
<Access [A]>
// atomic_op (B)
1: ldxr x0, [B] // Exclusive load
<op(B)>
stlxr w1, x0, [B] // Exclusive store with release
cbnz w1, 1b
dmb ish // Full barrier
<Access [C]>
The simple observations here are:
- The dmb ensures that no subsequent accesses (e.g. the access to C)
can enter or pass the atomic sequence.
- The dmb also ensures that no prior accesses (e.g. the access to A)
can pass the atomic sequence.
- Therefore, no prior access can pass a subsequent access, or
vice-versa (i.e. A is strictly ordered before C).
- The stlxr ensures that no prior access can pass the store component
of the atomic operation.
The only tricky part remaining is the ordering between the ldxr and the
access to A, since the absence of the first dmb means that we're now
permitting re-ordering between the ldxr and any prior accesses.
From an (arbitrary) observer's point of view, there are two scenarios:
1. We have observed the ldxr. This means that if we perform a store to
[B], the ldxr will still return older data. If we can observe the
ldxr, then we can potentially observe the permitted re-ordering
with the access to A, which is clearly an issue when compared to
the dmb variant of the code. Thankfully, the exclusive monitor will
save us here since it will be cleared as a result of the store and
the ldxr will retry. Notice that any use of a later memory
observation to imply observation of the ldxr will also imply
observation of the access to A, since the stlxr/dmb ensure strict
ordering.
2. We have not observed the ldxr. This means we can perform a store
and influence the later ldxr. However, that doesn't actually tell
us anything about the access to [A], so we've not lost anything
here either when compared to the dmb variant.
This patch implements this solution for our barriered atomic operations,
ensuring that we satisfy the full barrier requirements where they are
needed.
Cc: <stable@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 8e86f0b409)
Signed-off-by: Mark Brown <broonie@linaro.org>
The __sync_icache_dcache routine will only flush the dcache for the
first page of a compound page, potentially leading to stale icache
data residing further on in a hugetlb page.
This patch addresses this issue by taking into consideration the
order of the page when flushing the dcache.
Reported-by: Mark Brown <broonie@linaro.org>
Tested-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> # v3.11+
(cherry picked from commit 923b8f5044)
Signed-off-by: Mark Brown <broonie@linaro.org>
The architecture specification states that both DSB and ISB are required
between page table modifications and subsequent memory accesses using the
corresponding virtual address. When TLB invalidation takes place, the
tlb_flush_* functions already have the necessary barriers. However, there are
other functions like create_mapping() for which this is not the case.
The patch adds the DSB+ISB instructions in the set_pte() function for
valid kernel mappings. The invalid pte case is handled by tlb_flush_*
and the user mappings in general have a corresponding update_mmu_cache()
call containing a DSB. Even when update_mmu_cache() isn't called, the
kernel can still cope with an unlikely spurious page fault by
re-executing the instruction.
In addition, the set_pmd, set_pud() functions gain an ISB for
architecture compliance when block mappings are created.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Steve Capper <steve.capper@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
(cherry picked from commit 54d6ba0ede61f12b2a03d74bdbf004719a9cfefc)
Signed-off-by: Mark Brown <broonie@linaro.org>
The tlb maintainence functions: __cpu_flush_user_tlb_range and
__cpu_flush_kern_tlb_range do not take into consideration the page
granule when looping through the address range, and repeatedly flush
tlb entries for the same page when operating with 64K pages.
This patch re-works the logic s.t. we instead advance the loop by
1 << (PAGE_SHIFT - 12), so avoid repeating ourselves.
Also the routines have been converted from assembler to static inline
functions to aid with legibility and potential compiler optimisations.
The isb() has been removed from flush_tlb_kernel_range(.) as it is
only needed when changing the execute permission of a mapping. If one
needs to set an area of the kernel as execute/non-execute an isb()
must be inserted after the call to flush_tlb_kernel_range.
Cc: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit fa48e6f780)
Signed-off-by: Mark Brown <broonie@linaro.org>
The ASID is represented as an unsigned int in mm_context_t and we
currently use the mmid assembler macro to access this element of the
struct. This should be accessed with a register of 32-bit width. If
the incorrect register width is used the ASID will be returned in
bits[32:63] of the register when running under big-endian.
Fix a use of the mmid macro in tlb.S to use a 32-bit access.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit fc18047c73)
Signed-off-by: Mark Brown <broonie@linaro.org>
The kernel FDT functions predate libfdt and are much more limited in
functionality. Also, the kernel functions and libfdt functions are
not compatible with each other because they have different definitions
of node offsets. To avoid this incompatibility and in preparation to
add more FDT parsing functions which will need libfdt, let's first
convert the existing code to use libfdt.
The FDT unflattening, top-level FDT scanning, and property retrieval
functions are converted to use libfdt. The scanning code should be
re-worked to be more efficient and understandable by using libfdt to
find nodes directly by path or compatible strings.
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
(cherry picked from commit e6a6928c3e)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
drivers/of/fdt.c
Make of_get_flat_dt_prop arguments compatible with libfdt fdt_getprop
call in preparation to convert FDT code to use libfdt. Make the return
value const and the property length ptr type an int.
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
(cherry picked from commit 9d0c4dfedd)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
arch/arc/kernel/devtree.c
arch/arm/kernel/devtree.c
arch/arm/mach-exynos/exynos.c
arch/arm/plat-samsung/s5p-dev-mfc.c
arch/powerpc/kernel/epapr_paravirt.c
arch/powerpc/kernel/prom.c
arch/powerpc/mm/hash_utils_64.c
arch/powerpc/platforms/powernv/opal.c
arch/xtensa/kernel/setup.c
drivers/of/fdt.c
In tag next-20140407, building with CONFIG_DEBUG_SECTION_MISMATCH
enabled, the following WARNING is occured:
WARNING: drivers/built-in.o(.text.unlikely+0x2220): Section mismatch
in reference from the function __reserved_mem_check_root() to the
function .init.text:of_get_flat_dt_prop()
The function __reserved_mem_check_root() references
the function __init of_get_flat_dt_prop().
This is often because __reserved_mem_check_root lacks a __init
annotation or the annotation of of_get_flat_dt_prop is wrong.
WARNING: vmlinux.o(.text.unlikely+0xb9d0): Section mismatch in reference
from the function __reserved_mem_check_root() to the (unknown reference)
.init.data:(unknown)
The function __reserved_mem_check_root() references
the (unknown reference) __initdata (unknown).
This is often because __reserved_mem_check_root lacks a __initdata
annotation or the annotation of (unknown) is wrong.
This is cause by :
'drivers: of: add initialization code for dynamic reserved memory'.
Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Rob Herring <robh@kernel.org>
(cherry picked from commit 5b6241185e)
Signed-off-by: Mark Brown <broonie@linaro.org>
When the reserved memory patches hit -next, several legacy (non-DT) boot
failures were detected and bisected down to that commit. There needs to
be some sanity checking whether a DT is even present before parsing the
reserved ranges.
Reported-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
(cherry picked from commit 2040b52768)
Signed-off-by: Mark Brown <broonie@linaro.org>
Add support for custom reserved memory drivers. Call their init() function
for each reserved region and prepare for using operations provided by them
with by the reserved_mem->ops array.
Based on previous code provided by Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
(cherry picked from commit f618c4703a)
Signed-off-by: Mark Brown <broonie@linaro.org>
This patch adds support for dynamically allocated reserved memory regions
declared in device tree. Such regions are defined by 'size', 'alignment'
and 'alloc-ranges' properties.
Based on previous code provided by Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
(cherry picked from commit 3f0c820664)
Signed-off-by: Mark Brown <broonie@linaro.org>
This patch adds support for static (defined by 'reg' property) reserved
memory regions declared in device tree.
Memory blocks can be reliably reserved only during early boot. This must
happen before the whole memory management subsystem is initialized,
because we need to ensure that the given contiguous blocks are not yet
allocated by kernel. Also it must happen before kernel mappings for the
whole low memory are created, to ensure that there will be no mappings
(for reserved blocks). Typically, all this happens before device tree
structures are unflattened, so we need to get reserved memory layout
directly from fdt.
Based on previous code provided by Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
(cherry picked from commit e8d9d1f548)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
drivers/of/fdt.c
include/linux/of_fdt.h
Add a function to scan the flattened device-tree starting from the
node given by the path. It is used to extract information (like reserved
memory), which is required on early boot before we can unflatten the tree.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Tomasz Figa <t.figa@samsung.com>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>
(cherry picked from commit 57d74bcf30)
Signed-off-by: Mark Brown <broonie@linaro.org>
devicetrees may have a linux,stdout-path property in the chosen
node describing the console device. This adds a helper function
to match a device against this property so a driver can call
add_preferred_console for a matching device.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 5c19e95216)
Signed-off-by: Mark Brown <broonie@linaro.org>
On some PAE architectures, the entire range of physical memory could reside
outside the 32-bit limit. These systems need the ability to specify the
initrd location using 64-bit numbers.
This patch globally modifies the early_init_dt_setup_initrd_arch() function to
use 64-bit numbers instead of the current unsigned long.
There has been quite a bit of debate about whether to use u64 or phys_addr_t.
It was concluded to stick to u64 to be consistent with rest of the device
tree code. As summarized by Geert, "The address to load the initrd is decided
by the bootloader/user and set at that point later in time. The dtb should not
be tied to the kernel you are booting"
More details on the discussion can be found here:
https://lkml.org/lkml/2013/6/20/690https://lkml.org/lkml/2012/9/13/544
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
(cherry picked from commit 374d5c9964)
Signed-off-by: Mark Brown <broonie@linaro.org>
Add HYP and S2 page flags, for both normal and device memory.
Reviewed-by: Christopher Covington <cov@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 363116073a)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
arch/arm64/include/asm/pgtable-hwdef.h
arch/arm64/include/asm/pgtable.h
Fix for the arm64 kern_addr_valid() function to recognize
virtual addresses in the kernel logical memory map. The
function fails as written because it does not check whether
the addresses in that region are mapped at the pmd level to
2MB or 512MB pages, continues the page table walk to the
pte level, and issues a garbage value to pfn_valid().
Tested on 4K-page and 64K-page kernels.
Signed-off-by: Dave Anderson <anderson@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit da6e4cb67c)
Signed-off-by: Mark Brown <broonie@linaro.org>
The primary aim of this patchset is to remove the pgprot_default and
prot_sect_default global variables and rely strictly on predefined
values. The original goal was to be able to run SMP kernels on UP
hardware by not setting the Shareability bit. However, it is unlikely to
see UP ARMv8 hardware and even if we do, the Shareability bit is no
longer assumed to disable cacheable accesses.
A side effect is that the device mappings now have the Shareability
attribute set. The hardware, however, should ignore it since Device
accesses are always Outer Shareable.
Following the removal of the two global variables, there is some PROT_*
macro reshuffling and cleanup, including the __PAGE_* macros (replaced
by PAGE_*).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
(cherry picked from commit a501e32430)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
arch/arm64/include/asm/io.h
arch/arm64/include/asm/pgtable.h
arch/arm64/mm/mmu.c
At boot time, before switching to a virtual UEFI memory map, firmware
expects UEFI memory and IO regions to be identity mapped whenever
kernel makes runtime services calls. The existing early boot code
creates an identity map of kernel text/data but this is not sufficient
for UEFI. This patch adds a create_id_mapping() function which reuses
the core code of the existing create_mapping().
Signed-off-by: Mark Salter <msalter@redhat.com>
[ Fixed error message formatting (%pa). ]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
(cherry picked from commit d7ecbddf4c)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
arch/arm64/mm/mmu.c
Currently we place swapper_pg_dir and idmap_pg_dir below the kernel
image, between PHYS_OFFSET and (PHYS_OFFSET + TEXT_OFFSET). However,
bootloaders may use portions of this memory below the kernel and we do
not parse the memory reservation list until after the MMU has been
enabled. As such we may clobber some memory a bootloader wishes to have
preserved.
To enable the use of all of this memory by bootloaders (when the
required memory reservations are communicated to the kernel) it is
necessary to move our initial page tables elsewhere. As we currently
have an effectively unbound requirement for memory at the end of the
kernel image for .bss, we can place the page tables here.
This patch moves the initial page table to the end of the kernel image,
after the BSS. As they do not consist of any initialised data they will
be stripped from the kernel Image as with the BSS. The BSS clearing
routine is updated to stop at __bss_stop rather than _end so as to not
clobber the page tables, and memory reservations made redundant by the
new organisation are removed.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit bd00cd5f8c)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
arch/arm64/mm/init.c
With system caches for the host OS or architected caches for guest OS we
cannot easily guarantee that there are no dirty or stale cache lines for
the areas of memory written by the kernel during boot with the MMU off
(therefore non-cacheable accesses).
This patch adds the necessary cache maintenance during boot and relaxes
the booting requirements.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit c218bca74e)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
arch/arm64/kernel/head.S
Currently, the code for setting the __cpu_boot_mode flag is munged in
with el2_setup. This makes things difficult on a BE bringup as a
memory access has to have occurred before el2_setup which is the place
that we'd like to set the endianess on the current EL.
Create a new function for setting __cpu_boot_mode and have el2_setup
return the mode the CPU. Also define a new constant in virt.h,
BOOT_CPU_MODE_EL1, for readability.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 828e9834e9)
Signed-off-by: Mark Brown <broonie@linaro.org>
