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2018-04-24RISC-V: build vdso-dummy.o with -no-pieAurelien Jarno1-1/+1
Debian toolcahin defaults to PIE, and I guess that will also be the case of most distributions. This causes the following build failure: AS arch/riscv/kernel/vdso/getcpu.o AS arch/riscv/kernel/vdso/flush_icache.o VDSOLD arch/riscv/kernel/vdso/vdso.so.dbg OBJCOPY arch/riscv/kernel/vdso/vdso.so AS arch/riscv/kernel/vdso/vdso.o VDSOLD arch/riscv/kernel/vdso/vdso-dummy.o LD arch/riscv/kernel/vdso/vdso-syms.o riscv64-linux-gnu-ld: attempted static link of dynamic object `arch/riscv/kernel/vdso/vdso-dummy.o' make[2]: *** [arch/riscv/kernel/vdso/Makefile:43: arch/riscv/kernel/vdso/vdso-syms.o] Error 1 make[1]: *** [scripts/Makefile.build:575: arch/riscv/kernel/vdso] Error 2 make: *** [Makefile:1018: arch/riscv/kernel] Error 2 While the root Makefile correctly passes "-fno-PIE" to build individual object files, the RISC-V kernel also builds vdso-dummy.o as an executable, which is therefore linked as PIE. Fix that by updating this specific link rule to also include "-no-pie". Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-04Merge tag 'riscv-for-linus-4.17-mw0' of ↵Linus Torvalds8-19/+772
git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V updates from Palmer Dabbelt: "This contains the new features we'd like to incorporate into the RISC-V port for 4.17. We might have a bit more stuff land later in the merge window, but I wanted to get this out earlier just so everyone can see where we currently stand. A short summary of the changes is: - We've added support for dynamic ftrace on RISC-V targets. - There have been a handful of cleanups to our atomic and locking routines. They now more closely match the released RISC-V memory model draft. - Our module loading support has been cleaned up and is now enabled by default, despite some limitations still existing. - A patch to define COMMANDLINE_FORCE instead of COMMANDLINE_OVERRIDE so the generic device tree code picks up handling all our command line stuff. There's more information in the merge commits for each patch set" * tag 'riscv-for-linus-4.17-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: (21 commits) RISC-V: Rename CONFIG_CMDLINE_OVERRIDE to CONFIG_CMDLINE_FORCE RISC-V: Add definition of relocation types RISC-V: Enable module support in defconfig RISC-V: Support SUB32 relocation type in kernel module RISC-V: Support ADD32 relocation type in kernel module RISC-V: Support ALIGN relocation type in kernel module RISC-V: Support RVC_BRANCH/JUMP relocation type in kernel modulewq RISC-V: Support HI20/LO12_I/LO12_S relocation type in kernel module RISC-V: Support CALL relocation type in kernel module RISC-V: Support GOT_HI20/CALL_PLT relocation type in kernel module RISC-V: Add section of GOT.PLT for kernel module RISC-V: Add sections of PLT and GOT for kernel module riscv/atomic: Strengthen implementations with fences riscv/spinlock: Strengthen implementations with fences riscv/barrier: Define __smp_{store_release,load_acquire} riscv/ftrace: Add HAVE_FUNCTION_GRAPH_RET_ADDR_PTR support riscv/ftrace: Add DYNAMIC_FTRACE_WITH_REGS support riscv/ftrace: Add ARCH_SUPPORTS_FTRACE_OPS support riscv/ftrace: Add dynamic function graph tracer support riscv/ftrace: Add dynamic function tracer support ...
2018-04-04Merge branch 'irq-core-for-linus' of ↵Linus Torvalds2-17/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "The usual pile of boring changes: - Consolidate tasklet functions to share code instead of duplicating it - The first step for making the low level entry handler management on multi-platform kernels generic - A new sysfs file which allows to retrieve the wakeup state of interrupts. - Ensure that the interrupt thread follows the effective affinity and not the programmed affinity to avoid cross core wakeups. - Two new interrupt controller drivers (Microsemi Ocelot and Qualcomm PDC) - Fix the wakeup path clock handling for Reneasas interrupt chips. - Rework the boot time register reset for ARM GIC-V2/3 - Better suspend/resume support for ARM GIV-V3/ITS - Add missing locking to the ARM GIC set_type() callback - Small fixes for the irq simulator code - SPDX identifiers for the irq core code and removal of boiler plate - Small cleanups all over the place" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) openrisc: Set CONFIG_MULTI_IRQ_HANDLER arm64: Set CONFIG_MULTI_IRQ_HANDLER genirq: Make GENERIC_IRQ_MULTI_HANDLER depend on !MULTI_IRQ_HANDLER irqchip/gic: Take lock when updating irq type irqchip/gic: Update supports_deactivate static key to modern api irqchip/gic-v3: Ensure GICR_CTLR.EnableLPI=0 is observed before enabling irqchip: Add a driver for the Microsemi Ocelot controller dt-bindings: interrupt-controller: Add binding for the Microsemi Ocelot interrupt controller irqchip/gic-v3: Probe for SCR_EL3 being clear before resetting AP0Rn irqchip/gic-v3: Don't try to reset AP0Rn irqchip/gic-v3: Do not check trigger configuration of partitionned LPIs genirq: Remove license boilerplate/references genirq: Add missing SPDX identifiers genirq/matrix: Cleanup SPDX identifier genirq: Cleanup top of file comments genirq: Pass desc to __irq_free instead of irq number irqchip/gic-v3: Loudly complain about the use of IRQ_TYPE_NONE irqchip/gic: Loudly complain about the use of IRQ_TYPE_NONE RISC-V: Move to the new GENERIC_IRQ_MULTI_HANDLER handler genirq: Add CONFIG_GENERIC_IRQ_MULTI_HANDLER ...
2018-04-02RISC-V: Fixes to module loadingPalmer Dabbelt4-6/+338
This cleans up the module support that was commited earlier to work with what's actually emitted from our GCC port as it lands upstream. Most of the work here is adding new relocations to the kernel. There's some limitations on module loading imposed by the kernel: * The kernel doesn't support linker relaxation, which is necessary to support R_RISCV_ALIGN. In order to get reliable module building you're going to need to a GCC that supports the new '-mno-relax', which IIRC isn't going to be out until 8.1.0. It's somewhat unlikely that R_RISCV_ALIGN will appear in a module even without '-mno-relax' support, so issues shouldn't be common. * There is no large code model for RISC-V, which means modules must be loaded within a 32-bit signed offset of the kernel. We don't currently have any mechanism for ensuring this memory remains free or moving pages around, so issues here might be common. I fixed a singcle merge conflict in arch/riscv/kernel/Makefile.
2018-04-02RISC-V: Support SUB32 relocation type in kernel moduleZong Li1-0/+8
Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Support ADD32 relocation type in kernel moduleZong Li1-0/+8
Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Support ALIGN relocation type in kernel moduleZong Li1-0/+10
Just fail on align type. Kernel modules loader didn't do relax like linker, it is difficult to remove or migrate the code, but the remnant nop instructions harm the performaace of module. We expect the building module with the no-relax option. Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Support RVC_BRANCH/JUMP relocation type in kernel modulewqZong Li1-0/+35
Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Support HI20/LO12_I/LO12_S relocation type in kernel moduleZong Li1-0/+42
HI20 and LO12_I/LO12_S relocate the absolute address, the range of offset must in 32-bit. Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Support CALL relocation type in kernel moduleZong Li1-0/+22
Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Support GOT_HI20/CALL_PLT relocation type in kernel moduleZong Li1-10/+52
For CALL_PLT, emit the plt entry only when offset is more than 32-bit. For PCREL_LO12, it uses the location of corresponding HI20 to get the address of external symbol. It should check the HI20 type is the PCREL_HI20 or GOT_HI20, because sometime the location will have two or more relocation types. For example: 0: 00000797 auipc a5,0x0 0: R_RISCV_ALIGN *ABS* 0: R_RISCV_GOT_HI20 SYMBOL 4: 0007b783 ld a5,0(a5) # 0 <SYMBOL> 4: R_RISCV_PCREL_LO12_I .L0 4: R_RISCV_RELAX *ABS* Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Add section of GOT.PLT for kernel moduleZong Li2-2/+20
Separate the function symbol address from .plt to .got.plt section. The original plt entry has trampoline code with symbol address, there is a 32-bit padding bwtween jar instruction and symbol address. Extract the symbol address to .got.plt to reduce the module size. Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02RISC-V: Add sections of PLT and GOT for kernel moduleZong Li3-0/+147
The address of external symbols will locate more than 32-bit offset in 64-bit kernel with sv39 or sv48 virtual addressing. Module loader emits the GOT and PLT entries for data symbols and function symbols respectively. The PLT entry is a trampoline code for jumping to the 64-bit real address. The GOT entry is just the data symbol address. Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02riscv/ftrace: Add HAVE_FUNCTION_GRAPH_RET_ADDR_PTR supportAlan Kao2-1/+7
In walk_stackframe, the pc now receives the address from calling ftrace_graph_ret_addr instead of manual calculation. Note that the original calculation, pc = frame->ra - 4 is buggy when the instruction at the return address happened to be a compressed inst. But since it is not a critical part of ftrace, it is ignored for now to ease the review process. Cc: Greentime Hu <greentime@andestech.com> Signed-off-by: Alan Kao <alankao@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02riscv/ftrace: Add DYNAMIC_FTRACE_WITH_REGS supportAlan Kao2-0/+139
Cc: Greentime Hu <greentime@andestech.com> Signed-off-by: Alan Kao <alankao@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02riscv/ftrace: Add ARCH_SUPPORTS_FTRACE_OPS supportAlan Kao1-0/+3
Cc: Greentime Hu <greentime@andestech.com> Signed-off-by: Alan Kao <alankao@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02riscv/ftrace: Add dynamic function graph tracer supportAlan Kao2-1/+118
Once the function_graph tracer is enabled, a filtered function has the following call sequence: * ftracer_caller ==> on/off by ftrace_make_call/ftrace_make_nop * ftrace_graph_caller * ftrace_graph_call ==> on/off by ftrace_en/disable_ftrace_graph_caller * prepare_ftrace_return Considering the following DYNAMIC_FTRACE_WITH_REGS feature, it would be more extendable to have a ftrace_graph_caller function, instead of calling prepare_ftrace_return directly in ftrace_caller. Cc: Greentime Hu <greentime@andestech.com> Signed-off-by: Alan Kao <alankao@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02riscv/ftrace: Add dynamic function tracer supportAlan Kao4-12/+168
We now have dynamic ftrace with the following added items: * ftrace_make_call, ftrace_make_nop (in kernel/ftrace.c) The two functions turn each recorded call site of filtered functions into a call to ftrace_caller or nops * ftracce_update_ftrace_func (in kernel/ftrace.c) turns the nops at ftrace_call into a call to a generic entry for function tracers. * ftrace_caller (in kernel/mcount-dyn.S) The entry where each _mcount call sites calls to once they are filtered to be traced. Also, this patch fixes the semantic problems in mcount.S, which will be treated as only a reference implementation once we have the dynamic ftrace. Cc: Greentime Hu <greentime@andestech.com> Signed-off-by: Alan Kao <alankao@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff()Dominik Brodowski1-2/+2
Using this helper allows us to avoid the in-kernel calls to the sys_mmap_pgoff() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_mmap_pgoff(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mm@kvack.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-03-14RISC-V: Move to the new GENERIC_IRQ_MULTI_HANDLER handlerPalmer Dabbelt2-17/+3
The existing mechanism for handling IRQs on RISC-V is pretty ugly: the irq entry code selects the handler via Kconfig dependencies. Use the new generic IRQ handling infastructure, which allows boot time registration of the low level entry handler. This does add an additional load to the interrupt latency, but there's a lot of tuning left to be done there on RISC-V so it's OK for now. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Stafford Horne <shorne@gmail.com> Cc: jonas@southpole.se Cc: catalin.marinas@arm.com Cc: Will Deacon <will.deacon@arm.com> Cc: linux@armlinux.org.uk Cc: stefan.kristiansson@saunalahti.fi Cc: openrisc@lists.librecores.org Cc: linux-riscv@lists.infradead.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lkml.kernel.org/r/20180307235731.22627-3-palmer@sifive.com
2018-02-20Rename sbi_save to parse_dtb to improve code readabilityMichael Clark2-2/+2
The sbi_ prefix would seem to indicate an SBI interface, and save is not very specific. After applying this patch, reading head.S makes more sense. Signed-off-by: Michael Clark <michaeljclark@mac.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-02-20RISC-V: Enable IRQ during exception handlingzongbox@gmail.com1-2/+3
Interrupt is allowed during exception handling. There are warning messages if the kernel enables the configuration 'CONFIG_DEBUG_ATOMIC_SLEEP=y'. BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:23 in_atomic(): 0, irqs_disabled(): 1, pid: 43, name: ash CPU: 0 PID: 43 Comm: ash Tainted: G W 4.15.0-rc8-00089-g89ffdae-dirty #17 Call Trace: [<000000009abb1587>] walk_stackframe+0x0/0x7a [<00000000d4f3d088>] ___might_sleep+0x102/0x11a [<00000000b1fd792a>] down_read+0x18/0x28 [<000000000289ec01>] do_page_fault+0x86/0x2f6 [<00000000012441f6>] _do_fork+0x1b4/0x1e0 [<00000000f46c3e3b>] ret_from_syscall+0xa/0xe Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-02-07Merge tag 'riscv-for-linus-4.16-merge_window' of ↵Linus Torvalds7-42/+193
git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V updates from Palmer Dabbelt: "This contains the fixes we'd like to target for the 4.16 merge window. It's not as much as I was originally hoping to do but between glibc, the chip, and FOSDEM there just wasn't enough time to get everything put together. As such, this merge window is essentially just going to be small changes. This includes mostly cleanups: - A build fix failure to the audit test cases. RISC-V doesn't have renameat because the generic syscall ABI moved to renameat2 by the time of our port. The syscall audit test cases don't understand this, so I added a trivial fix. This went through mailing list review during the 4.15 merge window, but nobody has picked it up so I think it's best to just do this here. - The removal of our command-line argument processing code. The "mem_end" stuff was broken and the rest duplicated generic device tree code. The generic code was already being called. - Some unused/redundant code has been removed, including __ARCH_HAVE_MMU, current_pgdir, and the initialization of init_mm.pgd. - SUM is disabled upon taking a trap, which means that user memory is protected during traps taking inside copy_{to,from}_user(). - The sptbr CSR has been renamed to satp in C code. We haven't changed the assembly code in order to maintain compatibility with binutils 2.29, which doesn't understand the new name. Additionally, we're adding some new features: - Basic ftrace support, thanks to Alan Kao! - Support for ZONE_DMA32. This is necessary for all the normal reasons, but also to deal with a deficiency in the Xilinx PCIe controller we're using on our FPGA-based systems. While the ZONE_DMA32 addition should be sufficient for most uses, it doesn't complete the fix for the Xilinx controller. - TLB shootdowns now only target the harts where they're necessary, instead of applying to all harts in the system. These patches have all been sitting on our linux-next branch for a while now. Due to time constraints this is all I feel comfortable submitting during the 4.16 merge window, hopefully we'll do better next time!" [ Note to self: "harts" is RISC-V speak for "hardware threads". I had to look that up. - Linus ] * tag 'riscv-for-linus-4.16-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: riscv: inline set_pgdir into its only caller riscv: rename sptbr to satp riscv: don't read back satp in paging_init riscv: remove the unused current_pgdir function riscv: add ZONE_DMA32 RISC-V: Limit the scope of TLB shootdowns riscv: disable SUM in the exception handler riscv: remove redundant unlikely() riscv: remove unused __ARCH_HAVE_MMU define riscv/ftrace: Add basic support RISC-V: Remove mem_end command line processing RISC-V: Remove duplicate command-line parsing logic audit: Avoid build failures on systems without renameat
2018-01-31Merge branch 'work.whack-a-mole' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull asm/uaccess.h whack-a-mole from Al Viro: "It's linux/uaccess.h, damnit... Oh, well - eventually they'll stop cropping up..." * 'work.whack-a-mole' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: asm-prototypes.h: use linux/uaccess.h, not asm/uaccess.h riscv: use linux/uaccess.h, not asm/uaccess.h... ppc: for put_user() pull linux/uaccess.h, not asm/uaccess.h
2018-01-30riscv: rename sptbr to satpChristoph Hellwig1-3/+3
satp is the name used by the current privileged spec 1.10, use it instead of the old name. The most recent release binutils release (2.29) doesn't know about the satp name yet, so stick to the name from the previous privileged ISA release and comment on the fact. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-30riscv: add ZONE_DMA32Christoph Hellwig1-0/+9
This patch allows devices that require memory that can be addressed using 32-bit addresses to work easily on RISC-V systems. The newly improved dma-direct ops will tap into this pool automatically for 32-bit addressing. Based on an earlier patch from Wesley W. Terpstra. CC: Wesley W. Terpstra <terpstra@sifive.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-30riscv: disable SUM in the exception handlerChristoph Hellwig1-3/+6
The SUM bit is enabled at the beginning of the copy_{to,from}_user and {get,put}_user routines, and cleared before they return. But these user copy helper can be interrupted by exceptions, in which case the SUM bit will remain set, which leads to elevated privileges for the code running in exception context, as that can now access userspace address space unconditionally. This frequently happens when the user copy routines access freshly allocated user memory that hasn't been faulted in, and a pagefault needs to be taken before the user copy routines can continue. Fix this by unconditionally clearing SUM when the exception handler is called - the restore code will automatically restore it based on the saved value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-30riscv: remove redundant unlikely()Tobias Klauser1-1/+1
IS_ERR_VALUE() already implies unlikely(), so it can be omitted. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-30riscv/ftrace: Add basic supportAlan Kao3-0/+174
This patch contains basic ftrace support for RV64I platform. Specifically, function tracer (HAVE_FUNCTION_TRACER), function graph tracer (HAVE_FUNCTION_GRAPH_TRACER), and a frame pointer test (HAVE_FUNCTION_GRAPH_FP_TEST) are implemented following the instructions in Documentation/trace/ftrace-design.txt. Note that the functions in both ftrace.c and setup.c should not be hooked with the compiler's -pg option: to prevent infinite self- referencing for the former, and to ignore early setup stuff for the latter. Signed-off-by: Alan Kao <alankao@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-30RISC-V: Remove mem_end command line processingPalmer Dabbelt1-19/+0
This is just some cruft left over from before the port converted to device tree. The right way to handle memory regions is to specify them in the device tree, which BBL (our simplest bootloader) is already capable of doing. This patch simply removes the cruft. Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-30RISC-V: Remove duplicate command-line parsing logicMichael Clark1-16/+0
builtin_cmdline handling is present in drivers/of/fdt.c so the duplicate logic in arch/riscv/setup.c results in duplication of the builtin command line. e.g. CONFIG_CMDLINE="root=/dev/vda ro" gets appended twice and gives "root=/dev/vda ro root=/dev/vda ro" Before this patch: [ 0.000000] Kernel command line: root=/dev/vda ro root=/dev/vda ro After this patch: [ 0.000000] Kernel command line: root=/dev/vda ro Signed-off-by: Michael Clark <mjc@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-07riscv: rename SR_* constants to match the specChristoph Hellwig2-6/+6
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-07RISC-V: Make __NR_riscv_flush_icache visible to userspacePalmer Dabbelt2-2/+0
We were hoping to avoid making this visible to userspace, but it looks like we're going to have to because QEMU's user-mode emulation doesn't want to emulate a vDSO. Having vDSO-only system calls was a bit unothodox anyway, so I think in this case it's OK to just make the actual system call number public. This patch simply moves the definition of __NR_riscv_flush_icache availiable to userspace, which results in the deletion of the now empty vdso-syscalls.h. Changes since v1: * I've moved the definition into uapi/asm/syscalls.h rathen than uapi/asm/unistd.h. This allows me to keep asm/unistd.h, so we can keep the syscall table macros sane. * As a side effect of the above, this no longer disables all system calls on RISC-V. Whoops! Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-12-11RISC-V: Remove unused CONFIG_HVC_RISCV_SBI codePalmer Dabbelt1-11/+0
This is code that probably should never have made it into the kernel in the first place: it depends on a driver that hadn't been reviewed yet. During the HVC_SBI_RISCV review process a better way of doing this was suggested, but that means this code is defunct. It's compile-time disabled in 4.15 because the driver isn't in, so I think it's safe to just remove this for now. CC: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-12-11RISC-V: Logical vs Bitwise typoDan Carpenter1-1/+1
In the current code, there is a ! logical NOT where a bitwise ~ NOT was intended. It means that we never return -EINVAL. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-12-04riscv: use linux/uaccess.h, not asm/uaccess.h...Al Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-12-01RISC-V: Fixes for clean allmodconfig buildPalmer Dabbelt4-3/+15
Olaf said: Here's a short series of patches that produces a working allmodconfig. Would be nice to see them go in so we can add build coverage. I've dropped patches 8 and 10 from the original set: * [PATCH 08/10] (RISC-V: Set __ARCH_WANT_RENAMEAT to pick up generic version) has a better fix that I've sent out for review, we don't want renameat. * [PATCH 10/10] (input: joystick: riscv has get_cycles) has already been taken into Dmitry Torokhov's tree.
2017-11-30RISC-V: Clean up an unused includePalmer Dabbelt1-1/+0
We used to have some cmpxchg syscalls. They're no longer there, so we no longer need the include. CC: Christoph Hellwig <hch@infradead.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-11-30RISC-V: Allow userspace to flush the instruction cacheAndrew Waterman5-0/+67
Despite RISC-V having a direct 'fence.i' instruction available to userspace (which we can't trap!), that's not actually viable when running on Linux because the kernel might schedule a process on another hart. There is no way for userspace to handle this without invoking the kernel (as it doesn't know the thread->hart mappings), so we've defined a RISC-V specific system call to flush the instruction cache. This patch adds both a system call and a VDSO entry. If possible, we'd like to avoid having the system call be considered part of the user-facing ABI and instead restrict that to the VDSO entry -- both just in general to avoid having additional user-visible ABI to maintain, and because we'd prefer that users just call the VDSO entry because there might be a better way to do this in the future (ie, one that doesn't require entering the kernel). Signed-off-by: Andrew Waterman <andrew@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-11-30RISC-V: Flush I$ when making a dirty page executableAndrew Waterman1-0/+48
The RISC-V ISA allows for instruction caches that are not coherent WRT stores, even on a single hart. As a result, we need to explicitly flush the instruction cache whenever marking a dirty page as executable in order to preserve the correct system behavior. Local instruction caches aren't that scary (our implementations actually flush the cache, but RISC-V is defined to allow higher-performance implementations to exist), but RISC-V defines no way to perform an instruction cache shootdown. When explicitly asked to do so we can shoot down remote instruction caches via an IPI, but this is a bit on the slow side. Instead of requiring an IPI to all harts whenever marking a page as executable, we simply flush the currently running harts. In order to maintain correct behavior, we additionally mark every other hart as needing a deferred instruction cache which will be taken before anything runs on it. Signed-off-by: Andrew Waterman <andrew@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-11-30RISC-V: Provide stub of setup_profiling_timer()Olof Johansson1-0/+7
Fixes the following on allmodconfig build: profile.c:(.text+0x3e4): undefined reference to `setup_profiling_timer' Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-11-30RISC-V: Export some expected symbols for modulesOlof Johansson2-0/+5
These are the ones needed by current allmodconfig, so add them instead of everything other architectures are exporting -- the rest can be added on demand later if needed. Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-11-30RISC-V: move empty_zero_page definition to C and export itOlof Johansson2-3/+3
Needed by some modules (exported by other architectures). Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-11-27RISC-V: Add VDSO entries for clock_get/gettimeofday/getcpuAndrew Waterman6-1/+113
For now these are just placeholders that execute the syscall. We will later optimize them to avoid kernel crossings, but we'd like to have the VDSO entries from the first released kernel version to make the ABI simpler. Signed-off-by: Andrew Waterman <andrew@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-11-27RISC-V: Remove __vdso_cmpxchg{32,64} symbol versionsPalmer Dabbelt1-2/+0
These were left over from an earlier version of the port. Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-09-26RISC-V: Build InfrastructurePalmer Dabbelt3-0/+126
This patch contains all the build infrastructure that actually enables the RISC-V port. This includes Makefiles, linker scripts, and Kconfig files. It also contains the only top-level change, which adds RISC-V to the list of architectures that need a sed run to produce the ARCH variable when building locally. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26RISC-V: User-facing APIPalmer Dabbelt12-0/+977
This patch contains code that is in some way visible to the user: including via system calls, the VDSO, module loading and signal handling. It also contains some generic code that is ABI visible. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26RISC-V: Task implementationPalmer Dabbelt3-0/+915
This patch contains the implementation of tasks on RISC-V, most of which is involved in task switching. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26RISC-V: Generic library routines and assemblyPalmer Dabbelt1-0/+177
This patch contains code that is more specific to the RISC-V ISA than it is to Linux. It contains string and math operations, C wrappers for various assembly instructions, stack walking code, and uaccess. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26RISC-V: Init and Halt CodePalmer Dabbelt11-0/+1292
This contains the various __init C functions, the initial assembly kernel entry point, and the code to reset the system. When a file was init-related this patch contains the entire file. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>