- add new kernel memory layouts for MMUv3 cores: with 256MB and 512MB
KSEG size, starting at physical address other than 0;
- make kernel load address configurable;
- clean up kernel memory layout macros;
- drop sysmem early allocator and switch to memblock;
- enable kmemleak and memory reservation from the device tree;
- wire up new syscalls: userfaultfd, membarrier, mlock2, copy_file_range,
preadv2 and pwritev2;
- add new platform: Cadence Configurable System Platform (CSP) and new
core variant for it: xt_lnx;
- rearrange CCOUNT calibration code, make most of it generic;
- improve machine reset code (XTFPGA now reboots reliably with MMUv3
cores);
- provide default memmap command line option for configurations without
device tree support;
- ISS fixes: simdisk is now capable of using highmem pages, panic
correctly terminates simulator.
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Merge tag 'xtensa-20161005' of git://github.com/jcmvbkbc/linux-xtensa
Pull Xtensa updates from Max Filippov:
"Updates for the xtensa architecture. It is a combined set of patches
for 4.8 that never got to the mainline and new patches for 4.9.
- add new kernel memory layouts for MMUv3 cores: with 256MB and 512MB
KSEG size, starting at physical address other than 0
- make kernel load address configurable
- clean up kernel memory layout macros
- drop sysmem early allocator and switch to memblock
- enable kmemleak and memory reservation from the device tree
- wire up new syscalls: userfaultfd, membarrier, mlock2,
copy_file_range, preadv2 and pwritev2
- add new platform: Cadence Configurable System Platform (CSP) and
new core variant for it: xt_lnx
- rearrange CCOUNT calibration code, make most of it generic
- improve machine reset code (XTFPGA now reboots reliably with MMUv3
cores)
- provide default memmap command line option for configurations
without device tree support
- ISS fixes: simdisk is now capable of using highmem pages, panic
correctly terminates simulator"
* tag 'xtensa-20161005' of git://github.com/jcmvbkbc/linux-xtensa: (24 commits)
xtensa: disable MMU initialization option on MMUv2 cores
xtensa: add default memmap and mmio32native options to defconfigs
xtensa: add default memmap option to common_defconfig
xtensa: add default memmap option to iss_defconfig
xtensa: ISS: allow simdisk to use high memory buffers
xtensa: ISS: define simc_exit and use it instead of inline asm
xtensa: xtfpga: group platform_* functions together
xtensa: rearrange CCOUNT calibration
xtensa: xtfpga: use clock provider, don't update DT
xtensa: Tweak xuartps UART driver Rx watermark for Cadence CSP config.
xtensa: initialize MMU before jumping to reset vector
xtensa: fix icountlevel setting in cpu_reset
xtensa: extract common CPU reset code into separate function
xtensa: Added Cadence CSP kernel configuration for Xtensa
xtensa: fix default kernel load address
xtensa: wire up new syscalls
xtensa: support reserved-memory DT node
xtensa: drop sysmem and switch to memblock
xtensa: minimize use of PLATFORM_DEFAULT_MEM_{ADDR,SIZE}
xtensa: cleanup MMU setup and kernel layout macros
...
DT-enabled kernel should have a CPU node connected to a clock. This clock
is the CCOUNT clock. Use old platform_calibrate_ccount call as a fallback
when CPU node cannot be found or has no clock and in non-DT-enabled
configurations.
Drop no longer needed code that updates CPU clock-frequency property in
the DT; drop DT-related code from the platform_calibrate_ccount too.
Move of_clk_init to the top of time_init, so that clocks are initialized
before CCOUNT calibration is attempted.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
When reset is simulated MMU need to be brought into its initial state,
because that's what bootloaders/OS kernels assume. This is especially
important for MMUv3 because TLB state when the kernel is running is
significatly different from its reset state.
With this change it is possible to boot linux and get back to U-Boot
repeatedly.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
icountlevel SR value specifies lowest intlevel that does not do
instruction counting, so to disable instruction counting completely it
must be set to 0, not to 15.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
platform_restart implementatations do the same thing to reset CPU.
Don't duplicate that code, move it to a function and call it from
platform_restart.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This partially reverts commit 69d99e6c0d keeping only the main
purpose of the original commit which is the removal of
of_platform_populate() call. The moving of of_clk_init() caused changes
in the initialization order breaking booting.
Fixes: 69d99e6c0d ("xtensa: Remove unnecessary of_platform_populate with default match table")
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Commit 69d99e6c0d ("xtensa: Remove unnecessary of_platform_populate
with default match table") dropped various include files from
arch/xtensa/kernel/setup.c. This results in the following build error.
arch/xtensa/kernel/setup.c: In function ‘xtensa_dt_io_area’:
arch/xtensa/kernel/setup.c:213:2: error:
implicit declaration of function ‘of_read_ulong’
Fixes: 69d99e6c0d ("xtensa: Remove unnecessary of_platform_populate with default match table")
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Memblock is the standard kernel boot-time memory tracker/allocator. Use
it instead of the custom sysmem allocator. This allows using kmemleak,
CMA and device tree memory reservation.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Now that the kernel load address and KSEG physical base address have
their own Kconfig symbols PLATFORM_DEFAULT_MEM seems redundant. It makes
little sense to use it in MMU configurations instead of KSEG_PADDR.
In noMMU configurations there's no explicit KSEG, so it's still useful
for the early cache initialization and definition of ARCH_PFN_OFFSET,
which affects mem_map size.
- limit it to noMMU; MMU variants have XCHAL_KSEG_PADDR and
XCHAL_KSEG_SIZE;
- don't use it to define TASK_SIZE or MAX_LOW_PFN: first doesn't make
any difference in noMMU, second is meaningless as there's no high
memory;
- don't add default physical memory region: memory layout should come
from the DT, bootloader tags, or memmap= command line parameter.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
After patch "of/platform: Add common method to populate default bus",
it is possible for arch code to remove unnecessary callers of
of_platform_populate with default match table.
Move of_clk_init() into time_init(), then drop xtensa_device_probe() fully.
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Rob Herring <robh@kernel.org>
There are multiple factors adding to the issue in different
configurations:
- commit 17290231df ("xtensa: add fixup for double exception raised
in window overflow") added function window_overflow_restore_a0_fixup to
double exception vector overlapping reset vector location of secondary
processor cores.
- on MMUv2 cores RESET_VECTOR1_VADDR may point to uncached kernel memory
making code overlapping depend on cache type and size, so that without
cache or with WT cache reset vector code overwrites double exception
code, making issue even harder to detect.
- on MMUv3 cores RESET_VECTOR1_VADDR may point to unmapped area, as
MMUv3 cores change virtual address map to match MMUv2 layout, but
reset vector virtual address is given for the original MMUv3 mapping.
- physical memory region of the secondary reset vector is not reserved
in the physical memory map, and thus may be allocated and overwritten
at arbitrary moment.
Fix it as follows:
- move window_overflow_restore_a0_fixup code to .text section.
- define RESET_VECTOR1_VADDR so that it points to reset vector in the
cacheable MMUv2 map for cores with MMU.
- reserve reset vector region in the physical memory map. Drop separate
literal section and build mxhead.S with text section literals.
Cc: <stable@vger.kernel.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
KIO region location is different for noMMU cores. Provide different
default physical address and make KIO virtual address equal to physical.
Move xtensa_get_kio_paddr function close to XCHAL_KIO_PADDR definition
and define it not only for MMUv3, but for all MMU options except MMUv2.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
printk and friends can now format bitmaps using '%*pb[l]'. cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Unify the various architectures __dtb_start and __dtb_end definitions
moving them into of_fdt.h.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-metag@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-xtensa@linux-xtensa.org
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
This option is useful for reserving memory regions for secondary cores
in AMP configurations.
Implement the following memmap variants:
- memmap=nn[KMG]@ss[KMG]: force usage of a specific region of memory;
- memmap=nn[KMG]$ss[KMG]: mark specified memory as reserved;
- memmap=nn[KMG]: set end of memory.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Bootparam meminfo is a bootloader ABI, kernel meminfo is for the kernel
bookkeeping, keep them separate. Kernel doesn't care of memory region
types, so drop the type field and don't pass it to add_sysmem_bank.
Move kernel sysmem structures and prototypes to asm/sysmem.h and sysmem
variable and add_sysmem_bank to mm/init.c
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Use the simple-bus node to discover the io area, and remap the cached and
bypass io ranges. The parent-bus-address value of the first triplet in the
"ranges" property is used. This value is rounded down to the nearest 256MB
boundary. The length of the io area is fixed at 256MB; the "ranges" property
length value is ignored.
Other limitations: (1) only the first simple-bus node is considered, and (2)
only the first triplet of the "ranges" property is considered.
See ePAPR 1.1 §6.5 for the simple-bus node description, and §2.3.8 for the
"ranges" property description.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This is largely based on SMP code from the xtensa-2.6.29-smp tree by
Piet Delaney, Marc Gauthier, Joe Taylor, Christian Zankel (and possibly
other Tensilica folks).
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Secondary CPUs need this declaration to initialize their MMUs.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Otherwise exceptions may occur prior to exception handling mechanism
initialization, resulting in silently dead system.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
All arches do essentially the same thing now for
early_init_dt_setup_initrd_arch, so it can now be removed.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Convert xtensa to use new early_init_dt_scan function.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: linux-xtensa@linux-xtensa.org
Use the common unflatten_and_copy_device_tree to copy the built-in FDT
out of init section.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Acked-by: Grant Likely <grant.likely@linaro.org>
Use ccount_freq directly to make the code a little more readable.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
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>
flat DT copy code calls bootmem allocator with @align = 0.
This is probably OK with legacy allocator which xtensa uses right now,
but this will panic right away with memblock allocator
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Marc Gauthier <marc@tensilica.com>
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
The virtual address of boot parameters chain is passed to the kernel via
a2 register. Adjust it in case it is remapped during MMUv3 -> MMUv2
mapping change, i.e. when it is in the first 128M.
Also fix interpretation of initrd and FDT addresses passed in the boot
parameters: these are physical addresses.
Cc: stable@vger.kernel.org
Reported-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Add support for dispatching medium-priority interrupts, that is,
interrupts of priority levels 2 to EXCM_LEVEL. IRQ handling may be
preempted by higher priority IRQ.
Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Remove heading and trailing spaces, trim trailing lines, and wrap lines
that are longer than 80 characters.
Signed-off-by: Chris Zankel <chris@zankel.net>
Device trees allow specification of hardware topology and device
parameters at runtime instead of hard-coding them in platform setup
code. This allows running single binary kernel on a range of compatible
boards.
New boot parameters tag BP_TAG_FDT is allocated and a pointer to flat
device tree is passed in it.
Note that current interrupt mapping scheme uses single cell for
interrupt identification. That means that IRQ numbers used in DTS must
be CPU internal IRQ numbers, not external. It is possible to extend
interrupt identification to two cells, and use second cell to tell
external IRQ numbers form internal. That would allow to use single DTS
on multiple boards with different mapping of external IRQ numbers.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Add a brief sanity test of S32C1I functionality. This instruction
is needed by the kernel and userland as part of the base ABI
(including GCC atomic builtins, certain threading packages, future
atomic support in the C++ standard, etc). However, correct operation
of this instruction requires some cooperation by hardware external to
the processor (such as bus bridge, bus fabric, or memory controller).
Minimally exercising this mechanism and reporting explicit status
early in the boot process is helpful to chip vendors using the Linux
kernel as a benchmark of correctness of hardware.
As it turns out, S32C1I is not exercised by the kernel and by uClibc
based userland as of early June 2008. This is expected to change
soon as both incorporate more recent open source developments.
Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Boot parameter tags with handlers are ignored like this:
[ 0.000000] Ignoring tag 0x00001003
[ 0.000000] Ignoring tag 0x00001001
[ 0.000000] Ignoring tag 0x00001004
because neither tagtable entries nor tag handlers appear in the vmlinux.
Fix tagtable definition attributes so that tag entries are not dropped.
Fix end of memory bank calculation in parse_tag_mem: it is intended to
round down to page size, but instead did something strange leading to
hang right after boot.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Remove Kconfig entries, boot subdirectory, dependencies from other
boot-* Makefiles, and sections from ld scripts.
Remove stale redboot code that used to pass initrd addresses in a3 and
a4 to _start.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
* ->put_char changes
* HIGHMEM is bogus it seems, there is no kmap_atomic() et al
* some includes
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Chris Zankel <zankel@tensilica.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I don't know why this was there, but it was dead code.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: chris@zankel.net
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit
boundary. For example:
u64 val = PAGE_ALIGN(size);
always returns a value < 4GB even if size is greater than 4GB.
The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for
example):
#define PAGE_SHIFT 12
#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
...
#define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)
The "~" is performed on a 32-bit value, so everything in "and" with
PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary.
Using the ALIGN() macro seems to be the right way, because it uses
typeof(addr) for the mask.
Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in
include/linux/mm.h.
See also lkml discussion: http://lkml.org/lkml/2008/6/11/237
[akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c]
[akpm@linux-foundation.org: fix v850]
[akpm@linux-foundation.org: fix powerpc]
[akpm@linux-foundation.org: fix arm]
[akpm@linux-foundation.org: fix mips]
[akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c]
[akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c]
[akpm@linux-foundation.org: fix powerpc]
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Christian Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The header files in the asm-xtensa directory are not clean and
'make headers_check' fails. This is a first patch to fix most of
the header files. It removes unnecessary include statements and
adds some that are required for building the kernel. The linker
script required some updates or the linking stage would fail.
Signed-off-by: Chris Zankel <chris@zankel.net>