commit 7a1be318f5 ("ARM: 9012/1: move device tree mapping out of linear
region") use FDT_FIXED_BASE to map the whole FDT_FIXED_SIZE memory area
which contains fdt. But it only reserves the exact physical memory that
fdt occupied. Unfortunately, this mapping is non-shareable. An illegal or
speculative read access can bring the RAM content from non-fdt zone into
cache, PIPT makes it to be hit by subsequently read access through
shareable mapping(such as linear mapping), and the cache consistency
between cores is lost due to non-shareable property.
|<---------FDT_FIXED_SIZE------>|
| |
-------------------------------
| <non-fdt> | <fdt> | <non-fdt> |
-------------------------------
1. CoreA read <non-fdt> through MT_ROM mapping, the old data is loaded
into the cache.
2. CoreB write <non-fdt> to update data through linear mapping. CoreA
received the notification to invalid the corresponding cachelines, but
the property non-shareable makes it to be ignored.
3. CoreA read <non-fdt> through linear mapping, cache hit, the old data
is read.
To eliminate this risk, add a new memory type MT_MEMORY_RO. Compared to
MT_ROM, it is shareable and non-executable.
Here's an example:
list_del corruption. prev->next should be c0ecbf74, but was c08410dc
kernel BUG at lib/list_debug.c:53!
... ...
PC is at __list_del_entry_valid+0x58/0x98
LR is at __list_del_entry_valid+0x58/0x98
psr: 60000093
sp : c0ecbf30 ip : 00000000 fp : 00000001
r10: c08410d0 r9 : 00000001 r8 : c0825e0c
r7 : 20000013 r6 : c08410d0 r5 : c0ecbf74 r4 : c0ecbf74
r3 : c0825d08 r2 : 00000000 r1 : df7ce6f4 r0 : 00000044
... ...
Stack: (0xc0ecbf30 to 0xc0ecc000)
bf20: c0ecbf74 c0164fd0 c0ecbf70 c0165170
bf40: c0eca000 c0840c00 c0840c00 c0824500 c0825e0c c0189bbc c088f404 60000013
bf60: 60000013 c0e85100 000004ec 00000000 c0ebcdc0 c0ecbf74 c0ecbf74 c0825d08
... ... < next prev >
(__list_del_entry_valid) from (__list_del_entry+0xc/0x20)
(__list_del_entry) from (finish_swait+0x60/0x7c)
(finish_swait) from (rcu_gp_kthread+0x560/0xa20)
(rcu_gp_kthread) from (kthread+0x14c/0x15c)
(kthread) from (ret_from_fork+0x14/0x24)
The faulty list node to be deleted is a local variable, its address is
c0ecbf74. The dumped stack shows that 'prev' = c0ecbf74, but its value
before lib/list_debug.c:53 is c08410dc. A large amount of printing results
in swapping out the cacheline containing the old data(MT_ROM mapping is
read only, so the cacheline cannot be dirty), and the subsequent dump
operation obtains new data from the DDR.
Fixes: 7a1be318f5 ("ARM: 9012/1: move device tree mapping out of linear region")
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This implements create_mapping_late(), which we will use to populate
the UEFI Runtime Services page tables.
Tested-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Add basic NX support for kernel lowmem mappings. We mark any section
which does not overlap kernel text as non-executable, preventing it
from being used to write code and then execute directly from there.
This does not change the alignment of the sections, so the kernel
image doesn't grow significantly via this change, so we can do this
without needing a config option.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When using DEBUG_LL, the UART's (or other HW's) registers are mapped
into early page tables based on the results of assembly macro addruart.
Later, when the page tables are replaced, the same virtual address must
remain valid. Historically, this has been ensured by using defines from
<mach/iomap.h> in both the implementation of addruart, and the machine's
.map_io() function. However, with the move to single zImage, we wish to
remove <mach/iomap.h>. To enable this, the macro addruart may be used
when constructing the late page tables too; addruart is exposed as a
C function debug_ll_addr(), and used to set up the required mapping in
debug_ll_io_init(), which may called on an opt-in basis from a machine's
.map_io() function.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
[swarren: Mask map.virtual with PAGE_MASK. Checked for NULL results from
debug_ll_addr (e.g. when selected UART isn't valid). Fixed compile when
either !CONFIG_DEBUG_LL or CONFIG_DEBUG_SEMIHOSTING.]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
This adds a fixed virtual mapping for PCI i/o addresses. The mapping is
located at the last 2MB of vmalloc region (0xfee00000-0xff000000). 2MB
is used to align with PMD size, but IO_SPACE_LIMIT is 1MB. The space
is reserved after .map_io and can be mapped at any time later with
pci_ioremap_io. Platforms which need early i/o mapping (e.g. for vga
console) can call pci_map_io_early in their .map_io function.
This has changed completely from the 1st implementation which only
supported creating the static mapping at .map_io.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@linaro.org>
This patch adds support for CMA to dma-mapping subsystem for ARM
architecture. By default a global CMA area is used, but specific devices
are allowed to have their private memory areas if required (they can be
created with dma_declare_contiguous() function during board
initialisation).
Contiguous memory areas reserved for DMA are remapped with 2-level page
tables on boot. Once a buffer is requested, a low memory kernel mapping
is updated to to match requested memory access type.
GFP_ATOMIC allocations are performed from special pool which is created
early during boot. This way remapping page attributes is not needed on
allocation time.
CMA has been enabled unconditionally for ARMv6+ systems.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
CC: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Rob Clark <rob.clark@linaro.org>
Tested-by: Ohad Ben-Cohen <ohad@wizery.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Robert Nelson <robertcnelson@gmail.com>
Tested-by: Barry Song <Baohua.Song@csr.com>
On certain architectures, there might be a need to mark certain
addresses with strongly ordered memory attributes to avoid ordering
issues at the interconnect level.
On OMAP4, the asynchronous bridge buffers can only be drained
with strongly ordered accesses and hence the need to mark the
memory strongly ordered.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Woodruff Richard <r-woodruff2@ti.com>
Tested-by: Vishwanath BS <vishwanath.bs@ti.com>
The earlier TCM memory regions were mapped as MT_MEMORY_UNCACHED
which doesn't really work on platforms supporting the new v6
features like the NX bit. Add unique MT_MEMORY_[I|D]TCM types
instead.
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch provides a device drivers, which has a omap iommu, with
address mapping APIs between device virtual address(iommu), physical
address and MPU virtual address.
There are 4 possible patterns for iommu virtual address(iova/da) mapping.
|iova/ mapping iommu_ page
| da pa va (d)-(p)-(v) function type
---------------------------------------------------------------------------
1 | c c c 1 - 1 - 1 _kmap() / _kunmap() s
2 | c c,a c 1 - 1 - 1 _kmalloc()/ _kfree() s
3 | c d c 1 - n - 1 _vmap() / _vunmap() s
4 | c d,a c 1 - n - 1 _vmalloc()/ _vfree() n*
'iova': device iommu virtual address
'da': alias of 'iova'
'pa': physical address
'va': mpu virtual address
'c': contiguous memory area
'd': dicontiguous memory area
'a': anonymous memory allocation
'()': optional feature
'n': a normal page(4KB) size is used.
's': multiple iommu superpage(16MB, 1MB, 64KB, 4KB) size is used.
'*': not yet, but feasible.
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
This patch adds a Non-cacheable Normal ARM executable memory type,
MT_MEMORY_NONCACHED.
On OMAP3, this is used for rapid dynamic voltage/frequency scaling in
the VDD2 voltage domain. OMAP3's SDRAM controller (SDRC) is in the
VDD2 voltage domain, and its clock frequency must change along with
voltage. The SDRC clock change code cannot run from SDRAM itself,
since SDRAM accesses are paused during the clock change. So the
current implementation of the DVFS code executes from OMAP on-chip
SRAM, aka "OCM RAM."
If the OCM RAM pages are marked as Cacheable, the ARM cache controller
will attempt to flush dirty cache lines to the SDRC, so it can fill
those lines with OCM RAM instruction code. The problem is that the
SDRC is paused during DVFS, and so any SDRAM access causes the ARM MPU
subsystem to hang.
TI's original solution to this problem was to mark the OCM RAM
sections as Strongly Ordered memory, thus preventing caching. This is
overkill: since the memory is marked as non-bufferable, OCM RAM writes
become needlessly slow. The idea of "Strongly Ordered SRAM" is also
conceptually disturbing. Previous LAKML list discussion is here:
http://www.spinics.net/lists/arm-kernel/msg54312.html
This memory type MT_MEMORY_NONCACHED is used for OCM RAM by a future
patch.
Cc: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Mikael Pettersson reported:
The 2.6.28-rc kernels fail to detect PCI device 0000:00:01.0
(the first ethernet port) on my Thecus n2100 XScale box.
There is however still a strange "ghost" device that gets partially
detected in 2.6.28-rc2 vanilla.
The IOP321 manual says:
The user designates the memory region containing the OCCDR as
non-cacheable and non-bufferable from the IntelR XScaleTM core.
This guarantees that all load/stores to the OCCDR are only of
DWORD quantities.
Ensure that the OCCDR is so mapped.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As of the previous commit, MT_DEVICE_IXP2000 encodes to the same
PTE bit encoding as MT_DEVICE, so it's now redundant. Convert
MT_DEVICE_IXP2000 to use MT_DEVICE instead, and remove its aliases.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch provides an ARM implementation of ioremap_wc().
We use different page table attributes depending on which CPU we
are running on:
- Non-XScale ARMv5 and earlier systems: The ARMv5 ARM documents four
possible mapping types (CB=00/01/10/11). We can't use any of the
cached memory types (CB=10/11), since that breaks coherency with
peripheral devices. Both CB=00 and CB=01 are suitable for _wc, and
CB=01 (Uncached/Buffered) allows the hardware more freedom than
CB=00, so we'll use that.
(The ARMv5 ARM seems to suggest that CB=01 is allowed to delay stores
but isn't allowed to merge them, but there is no other mapping type
we can use that allows the hardware to delay and merge stores, so
we'll go with CB=01.)
- XScale v1/v2 (ARMv5): same as the ARMv5 case above, with the slight
difference that on these platforms, CB=01 actually _does_ allow
merging stores. (If you want noncoalescing bufferable behavior
on Xscale v1/v2, you need to use XCB=101.)
- Xscale v3 (ARMv5) and ARMv6+: on these systems, we use TEXCB=00100
mappings (Inner/Outer Uncacheable in xsc3 parlance, Uncached Normal
in ARMv6 parlance).
The ARMv6 ARM explicitly says that any accesses to Normal memory can
be merged, which makes Normal memory more suitable for _wc mappings
than Device or Strongly Ordered memory, as the latter two mapping
types are guaranteed to maintain transaction number, size and order.
We use the Uncached variety of Normal mappings for the same reason
that we can't use C=1 mappings on ARMv5.
The xsc3 Architecture Specification documents TEXCB=00100 as being
Uncacheable and allowing coalescing of writes, which is also just
what we need.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-02 21:32:35 +01:00
Renamed from include/asm-arm/mach/map.h (Browse further)
