We use virt_to_pte(NULL, va) a lot, which isn't very obvious.
I added virt_to_kpte(va) as a more obvious wrapper function,
that also validates the va as being a kernel adddress.
And, I fixed the semantics of virt_to_pte() so that we handle
the pud and pmd the same way, and we now document the fact that
we handle the final pte level differently.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Newer hypervisors have an API for reporting per-cpu statistics
information. This change allows seeing that information via
/sys/devices/system/cpu/cpuN/hv_stats file for each core.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Enter kernel debugger at boot with:
--hvd UART_1=1 --hvx kgdbwait --hvx kgdboc=ttyS1,115200
or at runtime with:
echo ttyS1,115200 > /sys/module/kgdboc/parameters/kgdboc
echo g > /proc/sysrq-trigger
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The existing code relied on the hardware definition (<arch/chip.h>)
to specify how much VA and PA space was available. It's convenient
to allow customizing this for some configurations, so provide symbols
MAX_PA_WIDTH and MAX_VA_WIDTH in <asm/page.h> that can be modified
if desired.
Additionally, move away from the MEM_XX_INTRPT nomenclature to
define the start of various regions within the VA space. In fact
the cleaner symbol is, for example, MEM_SV_START, to indicate the
start of the area used for supervisor code; the actual address of the
interrupt vectors is not as important, and can be changed if desired.
As part of this change, convert from "intrpt1" nomenclature (which
built in the old privilege-level 1 model) to a simple "intrpt".
Also strip out some tilepro-specific code supporting modifying the
PL the kernel could run at, since we don't actually support using
different PLs in tilepro, only tilegx.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Technically, user privilege is anything less than kernel
privilege. We modify the existing user_mode() macro to have
this semantic (and use it in a couple of places it wasn't being
used before), and add an IS_KERNEL_EX1() macro to the assembly
code as well.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
We remove some debug code in relocate_kernel_64.S that made raw
calls to the hv_console_putc Tilera hypervisor API, since everything
should funnel through the early_hv_write() API.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Previously, we used a special-purpose register (SPR_SYSTEM_SAVE_K_0)
to hold the CPU number and the top of the current kernel stack
by using the low bits to hold the CPU number, and using the high
bits to hold the address of the page just above where we'd want
the kernel stack to be. That way we could initialize a new SP
when first entering the kernel by just masking the SPR value and
subtracting a couple of words.
However, it's actually more useful to be able to place an arbitrary
kernel-top value in the SPR. This allows us to create a new stack
context (e.g. for virtualization) with an arbitrary top-of-stack VA.
To make this work, we now store the CPU number in the high bits,
above the highest legal VA bit (42 bits in the current tilegx
microarchitecture). The full 42 bits are thus available to store the
top of stack value. Getting the current cpu (a relatively common
operation) is still fast; it's now a shift rather than a mask.
We make this change only for tilegx, since tilepro has too few SPR
bits to do this, and we don't need this support on tilepro anyway.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
We use the validate_current() API to make sure that "current" seems
plausible before using it. With the new show_regs_print_info()
API, we want to check that current is OK before calling it, since
otherwise we will end up in a recursive panic.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
With this change such sections are grouped with regular text
in the vmlinux image; this change puts them at the front,
which is where the standard Linux includes .text.hot*.
This change should fix a recently-observed bug where a bunch of
symbols were being omitted from the /proc/kallsyms output
because they fell between _etext and _sinittext.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
We had been doing an automatic full eviction of the L1 I$
everywhere whenever we did a kernel-space TLB flush. It turns
out this isn't necessary, since all the callers already handle
doing a flush if necessary.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The r1 value is set based on the r0 value as we return to user space.
So tracing tools won't automatically see the right value. Fix this by
generating the correct r1 value in do_syscall_trace_exit() rather
than trying to tamper with the hot path in syscall return.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The "available_irqs" value needs to actually reflect the IRQs
available, not just start as an all-ones mask, since we only
have 32 IRQs available even on a 64-bit platform.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change includes support for Kprobes, Jprobes and Return Probes.
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Tony Lu <zlu@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This commit adds support for static ftrace, graph function support,
and dynamic tracer support.
Signed-off-by: Tony Lu <zlu@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds infrastructure (CONFIG_TILE_HVGLUE_TRACE) that
provides C code wrappers for the calls the kernel makes to the Tilera
hypervisor. This allows standard kernel infrastructure like FTRACE to
be able to instrument hypervisor calls.
To allow direct calls to the true API, we export their names with a
leading underscore as well. This is important for the few contexts
where we need to make hypervisor calls without touching the stack.
As part of this change, we also switch from creating the symbols
with linker magic to creating them with assembler magic. This lets
us provide a symbol type and generally make them appear more as symbols
and less as just random values in the Elf namespace.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change creates the framework for vDSO calls, makes the existing
rt_sigreturn() mechanism use it, and adds a fast gettimeofday().
Now that we need to expose the vDSO address to userspace, we add
AT_SYSINFO_EHDR to the set of aux entries provided to userspace.
(You can disable any extra vDSO support by booting with vdso=0,
but the rt_sigreturn vDSO page will still be provided.)
Note that glibc has supported the tile vDSO since release 2.17.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
First, don't re-enable interrupts blindly in the Linux trap handler.
We already handle page faults this way; synchronous interrupts like
ILL_TRANS will fire even when interrupts are disabled, and we don't
want to re-enable interrupts in that case.
For ILL_TRANS, we now pass the ILL_VA_PC reason into the trap handler
so we can report it properly; this is the address that caused the
illegal translation trap. We print the address as part of the
pr_alert() message now if it's coming from the kernel.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
It's much easier to read register dumps if you read vertically
rather than horizontally, since the register numbers line up
and lead the eye down more than to the right.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
First, fix a bug in asm/unaligned.h; we need to just use the asm-generic
unaligned.h so we properly choose endian-correct flavors.
Second, keep the hv/hypervisor.h ABI fully "native" in the sense that
we don't have __BIG_ENDIAN__ ifdefs there. Instead, we use macros in
the head_NN.S assembly code to properly extract two 32-bit structure
members from a 64-bit register holding the structure.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds support for CONFIG_PREEMPT (full kernel preemption).
In addition to the core support, this change includes a number
of places where we fix up uses of smp_processor_id() and per-cpu
variables. I also eliminate the PAGE_HOME_HERE and PAGE_HOME_UNKNOWN
values for page homing, as it turns out they weren't being used.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds support for avoiding recursive backtracer crashes;
we haven't seen this in practice other than when things are seriously
corrupt, but it may help avoid losing the root cause of a crash.
Also, don't abort kernel backtracers for invalid userspace PC's.
If we do, we lose the ability to backtrace through a userspace
call to a bad address above PAGE_OFFSET, even though that it can
be perfectly reasonable to continue the backtrace in such a case.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change enables unaligned userspace memory access via a kernel
fast path on tilegx. The kernel tracks user PC/instruction pairs
per-thread using a direct-mapped cache in userspace. The cache
maps those PC/instruction pairs to JIT'ed instruction sequences that
load or store using byte-wide load store intructions and then
synthesize 2-, 4- or 8-byte load or store results. Once an
instruction has been seen to generate an unaligned access once,
subsequent hits on that instruction typically require overhead
of only around 50 cycles if cache and TLB is hot.
We support the prctl() PR_GET_UNALIGN / PR_SET_UNALIGN sys call to
enable or disable unaligned fixups on a per-process basis.
To do this we pull some of the tilepro unaligned support out of the
single_step.c file; tilepro uses instruction disassembly for both
single-step and unaligned access support. Since tilegx actually has
hardware singlestep support, though, it's cleaner to keep the tilegx
unaligned access code in a separate file. While we're at it,
properly rename the tilepro-specific types, etc., to have tilepro
suffixes instead of generic tile suffixes.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Pointed out by checkpatch. A few of the DEFINE() lines were
properly written without backslash continuation; fix the rest.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change adds support for the "memmap" boot parameter similar
to what x86 provides. The tile version supports "memmap=1G$5G",
for example, as a way to reserve a 1 GB range starting at PA 5GB.
The memory is reserved via bootmem during startup, and we create a
suitable "struct resource" marked as "Reserved" so you can see the
range reported by /proc/iomem. Up to 64 such regions can currently
be reserved on the boot command line.
We do not support the x86 options "memmap=nn@ss" (force some memory
to be available at the given address) since it's pointless to try to
have Linux use memory the Tilera hypervisor hasn't given it. We do
not support "memmap=nn#ss" to add an ACPI range for later processing,
since we don't support ACPI. We do not support "memmap=exactmap"
since we don't support reading the e820 information from the BIOS
like x86 does. I did add support for "memmap=nn" (and the synonym
"mem=nn") which cap the highest PA value at "nn"; these are both
just a synonym for the existing tile boot option "maxmem".
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This change improves and cleans up the tile console.
- We enable HVC_IRQ support on tilegx, with the addition of a new
Tilera hypervisor API for tilegx to allow a console IPI. If IPI
support is not available we fall back to the previous polling mode.
- We simplify the earlyprintk code to use CON_BOOT and eliminate some
of the other supporting earlyprintk code.
- A new tile_console_write() primitive is used to send output to
the console and is factored out of the hvc_tile driver.
This lets us support a "sim_console" boot argument to allow using
simulator hooks to send output to the "console" as a slightly
faster alternative to emulating the hardware more directly.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We can take advantage of the fact that bit 29 is hard-wired
to zero in register TRIO_TILE_PIO_REGION_SETUP_CFG_ADDR.
This is handy since at the moment we only allocate one 4GB
region for vmalloc, and with this change we can allocate
four or more TRIO MACs without using up all the vmalloc space.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
On Tilera Gx72 systems, the logic for figuring out whether
a given port is root complex is slightly different.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The code incorrectly masked with PAGE_OFFSET instead of
PAGE_SIZE-1. This only matters when trying to do a
non page-aligned DMA; it was noticed during code inspection.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The standard kernel function dma_get_required_mask() uses the
highest DRAM address to determine if 32-bit or 64-bit DMA addressing
is needed. This only works on architectures that have direct mapping
between the PA and the PCI address space, i.e. those that don't have
I/O TLBs or have I/O TLB but choose to use direct mapping. Neither
of these are true for tilegx. Whether to use 64-bit DMA should depend
on the PCI device's capability only, not on the amount of DRAM
installeds, so we now advertise a 64-bit DMA mask unconditionally.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Using the low-level hv_dev_pread() API makes assumptions about the
layout of datastructures in the Tilera hypervisor API; it's better to
use the gxio_XXX accessor and the pcie_trio_ports_property struct.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The .mem_resources[] field in the pci_controller struct
is now obsoleted by the .mem_space and .io_space fields.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The TRIO shim initialization is shared with other kernel drivers
such as the endpoint and StreamIO drivers, so reorganize the
initialization flow to ensure that the root complex driver properly
initializes TRIO state regardless of what kind of TRIO driver will
end up using the shim.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
To enable this functionality, configure CONFIG_TILE_PCI_IO. Without
this flag, the kernel still assigns I/O address ranges to the
devices, but no TRIO resource and mapping support is provided.
We assign disjoint I/O address ranges to separate PCIe domains.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Besides using pr_info() to print the linkdown status for a plug-in
slot, add extra indication that this is expected if the slot is empty.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
To support PCIe devices with higher number of MSI-X interrupt vectors,
e.g. 16 for the LSI RAID card, enhance the Gx RC stack to provide more
MSI-X vectors by using the TRIO Scatter Queues, which provide 8 more
vectors in addition to ~10 from the Map Mem regions.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The LSI MEGARAID SAS HBA suffers from the problem where it can do
64-bit DMA to streaming buffers but not to consistent buffers.
In other words, 64-bit DMA is used for disk data transfers and 32-bit
DMA must be used for control message transfers. According to LSI,
the firmware is not fully functional yet. This change implements a
kind of hybrid dma_ops to support this.
Note that on most other platforms, the 64-bit DMA addressing space is the
same as the 32-bit DMA space and they overlap the physical memory space.
No special arrangement is needed to support this kind of mixed DMA
capability. On TILE-Gx, the 64-bit DMA space is completely separate
from the 32-bit DMA space. Due to the use of the IOMMU, the 64-bit DMA
space doesn't overlap the physical memory space. On the other hand,
the 32-bit DMA space overlaps the physical memory space under 4GB.
The separate address spaces make it necessary to have separate dma_ops.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
If we are rebooting (e.g. via kexec) then the PCI RC link may
already be up. In that case, we don't want to do the software
fixup to force the link up, since that can degrade it to Gen1.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Allow longer delays if requested, and print the info messages
as we are performing the delay, not when parsing the arguments.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Fix a bug in the tilepro PCI resource allocation code that could make
the bootmem allocator unhappy if 4GB is installed on mshim 0.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
- remove unneeded <linux/bootmem.h> include in pci.c
- eliminate unused pci_controller.first_busno field
- prefer msleep to mdelay
- remove stale comment about pci_scan_bus_parented()
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
The "inv" (invalidate) instruction is generally less safe than "finv"
(flush and invalidate), as it will drop dirty data from the cache.
It turns out we have almost no need for "inv" (other than for the
older 32-bit architecture in some limited cases), so convert to
"finv" where possible and delete the extra "inv" infrastructure.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
First, clean up active hardwalls in exit_thread(). This is a better
place than in arch_release_thread_info().
Second, mask out any non-online cpus from the cpumask after
validating any required semantics of the cpu set.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Normalize global variables exported by vmlinux.lds to conform usage
guidelines from include/asm-generic/sections.h.
1) Use _text to mark the start of the kernel image including the head
text, and _stext to mark the start of the .text section.
2) Export mandatory global variables __init_begin and __init_end.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time
back and the comments/Documentation never got updated.
I figured it out when I was going through sched-domains.txt and so thought of
fixing it globally.
I haven't crossed check if the stuff that is referenced in sched/core.c by all
these files is still present and hasn't changed as that wasn't the motive behind
this patch.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
