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2013-09-03tile: remove support for TILE64Chris Metcalf
This chip is no longer being actively developed for (it was superceded by the TILEPro64 in 2008), and in any case the existing compiler and toolchain in the community do not support it. It's unlikely that the kernel works with TILE64 at this point as the configuration has not been tested in years. The support is also awkward as it requires maintaining a significant number of ifdefs. So, just remove it altogether. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: use asm-generic/bitops/builtin-*.hAkinobu Mita
The definisions of __ffs(), __fls(), and ffs() for tile are almost same as asm-generic/bitops-*.h. The only difference is that it is defined as __always_inline or inline. So this switches to use those headers. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [moved #includes to end]
2013-09-03tile: eliminate no-op "noatomichash" boot argumentChris Metcalf
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: use standard tile_bundle_bits type in traps.cChris Metcalf
We were rolling our own bundle_bits, which is unnecessary. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: simplify code referencing hypervisor API addressesChris Metcalf
There's no need to make up new ways of computing the addresses of the Tilera hypervisor APIs; just use the standard method of relying on the symbols to provide the addresses. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: change <asm/system.h> to <asm/switch_to.h> in commentsChris Metcalf
Also fix mentions of it in #error statements. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: mark pcibios_init() as __initChris Metcalf
It was bombed away because it was previously marked as __devinit, but it should be an __init function. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: check for correct compiler earlier in asm-offsets.cChris Metcalf
If we wait until after including a bunch of other files, we will have generated so much warning spew that it's hard to notice the error about using the wrong compiler. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: use standard 'generic-y' model for <asm/hw_irq.h>Chris Metcalf
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: use asm-generic version of <asm/local64.h>Chris Metcalf
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile PCI RC: add comment about "PCI hole" problemChris Metcalf
Explain the rationale of not overlapping the 64-bit DMA window with the PA range. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: remove DEBUG_EXTRA_FLAGS kernel config optionChris Metcalf
It isn't used any more by us now that the generic kernel build offers DEBUG_INFO_REDUCED, so just get rid of it. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: add virt_to_kpte() API and clean up and document behaviorChris Metcalf
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>
2013-09-03tile: support FRAME_POINTERChris Metcalf
Allow enabling frame pointer support; this makes it easier to hook into the various kernel features that claim they require it without having to add Kconfig conditionals everywhere (a la mips, ppc, s390, and microblaze). When enabled, it basically eliminates leaf functions as such, and stops optimizing tail and sibling calls. It adds around 3% to the size of the kernel when enabled. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: support reporting Tilera hypervisor statisticsChris Metcalf
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>
2013-09-03tilegx: support KGDBChris Metcalf
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>
2013-09-03tilegx: provide kernel support for the tilegx UART shimChris Metcalf
The TILE-Gx chip includes an on-chip UART. This change adds support for using the UART from within the kernel. The UART shim has more functionality than is exposed here, but to keep the kernel code and binary simpler, this is a subset of the full API designed to enable a standard Linux tty serial driver only. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03tile: parameterize VA and PA space more cleanlyChris Metcalf
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>
2013-09-03tile: don't assume user privilege is zeroChris Metcalf
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>
2013-09-03tile: clean up relocate_kernel_64 debug codeChris Metcalf
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>
2013-08-30tile: handle super huge pages in virt_to_pteChris Metcalf
This tile-specific API had a minor bug, in that if a super huge (>4GB) page mapped a particular address range, we wouldn't handle it correctly. As part of fixing that bug, I also cleaned up some of the pud and pmd accessors to make them more consistent. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tilegx: change how we find the kernel stackChris Metcalf
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>
2013-08-30tile: don't call show_regs_print_info() with corrupt currentChris Metcalf
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>
2013-08-30tile: fix some -Wsign-compare warningsChris Metcalf
Normally the build doesn't include these warnings, but at one point I built with -Wsign-compare, and noticed a few things that are technically bugs. This change fixes those things. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: group .hottext* sections properly in vmlinux.ldsChris Metcalf
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>
2013-08-30tile: fix strncpy_from_user bugChris Metcalf
In strncpy_from_user_asm, when the destination buffer length was the same as the actual string length, we were returning the size of the destination buffer. But since it's a NUL terminated string, we should return the length of the string instead. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: remove set/clear_fixmap APIsChris Metcalf
Nothing in the codebase was using them, and as written they took "unsigned long" as the physical address rather than "phys_addr_t", which is wrong on tilepro anyway. Rather than fixing stale APIs, just remove them; if there's ever demand for them on this platform, we can put them back. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: do less L1 I-cache evictionChris Metcalf
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>
2013-08-30tile: allow "initrd" boot argument for kexecChris Metcalf
This enables support for "kexec --initrd" for tile. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: support ASLR fullyTony Lu
With this change, tile Linux now supports address-space layout randomization for shared objects, stack, heap and vdso. Acked-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Tony Lu <zlu@tilera.com> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: correct r1 value during syscall tracingChris Metcalf
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>
2013-08-30tile: fix panic with large IRQ numberChris Metcalf
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>
2013-08-30tile: use proper .align directives on __ex_table sectionsChris Metcalf
This may fix a reported bug where an R_TILEGX_64 in a module was not pointing to an aligned address. Reported-by: Simon Marchi <simon.marchi@polymtl.ca> Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-30tile: support kprobes on tilegxTony Lu
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>
2013-08-30tile: support ftrace on tilegxTony Lu
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>
2013-08-13tile: provide traceability for hypervisor callsChris Metcalf
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>
2013-08-13tile: avoid struct vm_struct leakChris Metcalf
If ioreamp_prot() fails in ioremap_page_range() due to kernel memory exhaustion, we previously would leak a struct vm_struct. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: implement gettimeofday() via vDSOChris Metcalf
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>
2013-08-13tile: support simulator notification for ET_DYN objectsChris Metcalf
The tile code notifies the simulator of new ET_EXEC objects starting to execute so that tracing code can properly annotate the objects. However, we didn't support ET_DYN executables like ld.so, so we didn't properly load symbols, etc. This change enables that support; we use a variant of the SIM_CONTROL_DLOPEN simulator notification that newer simulators will recognize and use to set the base address for the next SIM_CONTROL_OS_EXEC notification. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: improve illegal translation interrupt handlingChris Metcalf
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>
2013-08-13tile: make register dumps more readableChris Metcalf
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>
2013-08-13tile: improve big-endian supportChris Metcalf
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>
2013-08-13tile: support CONFIG_PREEMPTChris Metcalf
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>
2013-08-13tile: remove calls to arch_flush_lazy_mmu_mode()Chris Metcalf
Since it's a no-op on tile anyway, there's no reason to be calling it in tile-specific code. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: fix some issues in hugepage supportChris Metcalf
First, in huge_pte_offset(), we were erroneously checking pgd_present(), which is always true, rather than pud_present(), which is the thing that tells us if there is a top-level (L0) PTE. Fixing this means we properly look up huge page entries only when the Present bit is actually set in the PTE. Second, use the standard pte_alloc_map() instead of the hand-rolled pte_alloc_hugetlb() routine that basically was written to avoid worrying about CONFIG_HIGHPTE. However, we no longer plan to support HIGHPTE, so a separate routine was just unnecessary code duplication. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13tile: avoid recursive backtrace faultsChris Metcalf
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>
2013-08-13tile: fast-path unaligned memory access for tilegxChris Metcalf
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>
2013-08-12tile: remove unnecessary backslashes in asm-offsets.cChris Metcalf
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>
2013-08-12tile: fix tilegx vmalloc_sync_all BUG_ONChris Metcalf
As specified, the test wasn't correct, and in any case it should be a BUILD_BUG_ON. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-12tile: fix comment bug in sys_cmpxchg descriptionChris Metcalf
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>