summaryrefslogtreecommitdiff
path: root/target/xtensa/cpu.h
AgeCommit message (Collapse)Author
2020-01-15target/xtensa: Remove MMU_MODE{0,1,2,3}_SUFFIXRichard Henderson
The functions generated by these macros are unused. Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-01-06target/xtensa: fix ps.ring use in MPU configsMax Filippov
Allow ps.ring modification by wsr.ps/xsr.ps and use ps.ring value in xtensa_get_[c]ring on configurations with MPU. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-09-11target/xtensa: linux-user: add call0 ABI supportMax Filippov
Xtensa binaries built for call0 ABI don't rotate register window on function calls and returns. Invocation of signal handlers from the kernel is therefore different in windowed and call0 ABIs. There's currently no way to determine xtensa ELF binary ABI from the binary itself. Add handler for the -xtensa-abi-call0 command line parameter/QEMU_XTENSA_ABI_CALL0 envitonment variable to the qemu-user and record ABI choice. Use it to initialize PS.WOE in xtensa_cpu_reset. Check PS.WOE in setup_rt_frame to determine how a signal should be delivered. Reviewed-by: Laurent Vivier <laurent@vivier.eu> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Message-Id: <20190906165713.5558-1-jcmvbkbc@gmail.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-08-20configure: Define target access alignment in configuretony.nguyen@bt.com
This patch moves the define of target access alignment earlier from target/foo/cpu.h to configure. Suggested in Richard Henderson's reply to "[PATCH 1/4] tcg: TCGMemOp is now accelerator independent MemOp" Signed-off-by: Tony Nguyen <tony.nguyen@bt.com> Message-Id: <11e818d38ebc40e986cfa62dd7d0afdc@tpw09926dag18e.domain1.systemhost.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: tony.nguyen@bt.com <tony.nguyen@bt.com>
2019-06-12Include qemu-common.h exactly where neededMarkus Armbruster
No header includes qemu-common.h after this commit, as prescribed by qemu-common.h's file comment. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-5-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and net/tap-bsd.c fixed up]
2019-06-10cpu: Remove CPU_COMMONRichard Henderson
This macro is now always empty, so remove it. This leaves the entire contents of CPUArchState under the control of the guest architecture. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10cpu: Introduce CPUNegativeOffsetStateRichard Henderson
Nothing in there so far, but all of the plumbing done within the target ArchCPU state. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10cpu: Move ENV_OFFSET to exec/gen-icount.hRichard Henderson
Now that we have ArchCPU, we can define this generically, in the one place that needs it. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10target/xtensa: Use env_cpu, env_archcpuRichard Henderson
Cleanup in the boilerplate that each target must define. Replace xtensa_env_get_cpu with env_archcpu. The combination CPU(xtensa_env_get_cpu) should have used ENV_GET_CPU to begin; use env_cpu now. Move cpu_get_tb_cpu_state below the include of "exec/cpu-all.h" so that the definition of env_cpu is available. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10cpu: Replace ENV_GET_CPU with env_cpuRichard Henderson
Now that we have both ArchCPU and CPUArchState, we can define this generically instead of via macro in each target's cpu.h. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Acked-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10cpu: Define ArchCPURichard Henderson
For all targets, do this just before including exec/cpu-all.h. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Acked-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10cpu: Define CPUArchState with typedefRichard Henderson
For all targets, do this just before including exec/cpu-all.h. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Acked-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10tcg: Split out target/arch/cpu-param.hRichard Henderson
For all targets, into this new file move TARGET_LONG_BITS, TARGET_PAGE_BITS, TARGET_PHYS_ADDR_SPACE_BITS, TARGET_VIRT_ADDR_SPACE_BITS, and NB_MMU_MODES. Include this new file from exec/cpu-defs.h. This now removes the somewhat odd requirement that target/arch/cpu.h defines TARGET_LONG_BITS before including exec/cpu-defs.h, so push the bulk of the includes within target/arch/cpu.h to the top. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Acked-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-05-21Merge remote-tracking branch 'remotes/xtensa/tags/20190520-xtensa' into stagingPeter Maydell
target/xtensa: SR reorganization and options for modern cores Reorganize special register handling to support configurations with conflicting SR definitions. Implement options used by the modern xtensa cores: - memory protection unit; - block prefetch; - exclusive access Add special register definitions and IRQ types for ECC/parity, gather/scatter and IDMA. # gpg: Signature made Mon 20 May 2019 18:53:05 BST # gpg: using RSA key 2B67854B98E5327DCDEB17D851F9CC91F83FA044 # gpg: issuer "jcmvbkbc@gmail.com" # gpg: Good signature from "Max Filippov <filippov@cadence.com>" [unknown] # gpg: aka "Max Filippov <max.filippov@cogentembedded.com>" [full] # gpg: aka "Max Filippov <jcmvbkbc@gmail.com>" [full] # Primary key fingerprint: 2B67 854B 98E5 327D CDEB 17D8 51F9 CC91 F83F A044 * remotes/xtensa/tags/20190520-xtensa: target/xtensa: implement exclusive access option target/xtensa: update list of exception causes target/xtensa: implement block prefetch option opcodes target/xtensa: implement DIWBUI.P opcode target/xtensa: implement MPU option target/xtensa: add parity/ECC option SRs target/xtensa: define IDMA and gather/scatter IRQ types target/xtensa: make internal MMU functions static target/xtensa: get rid of centralized SR properties Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-05-15target/xtensa: implement exclusive access optionMax Filippov
The Exclusive Instructions provide a general-purpose mechanism for atomic updates of memory-based synchronization variables that can be used for exclusion algorithms. Use cmpxchg-based implementation that is sufficient for the typical use of exclusive access in atomic operations. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-15target/xtensa: update list of exception causesMax Filippov
Add XEA2 exception cause codes defined in recent Xtensa ISA releases. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-14target/xtensa: implement DIWBUI.P opcodeMax Filippov
This is a recent addition to the set of data cache opcodes. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-10target/xtensa: implement MPU optionMax Filippov
The Memory Protection Unit Option (MPU) is a combined instruction and data memory protection unit with more protection flexibility than the Region Protection Option or the Region Translation Option but without any translation capability. It does no demand paging and does not reference a memory-based page table. Add memory protection unit option, internal state, SRs and opcodes. Implement MPU entries dumping in dump_mmu. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-10target/xtensa: add parity/ECC option SRsMax Filippov
Add SRs and rsr/wsr/xsr opcodes defined by the parity/ECC xtensa option. The implementation is trivial since we don't emulate parity/ECC yet. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-10target/xtensa: define IDMA and gather/scatter IRQ typesMax Filippov
IDMA and scatter/gather features introduced new IRQ types that overlay_tool.h need to initialize Xtensa configuration. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-10target/xtensa: make internal MMU functions staticMax Filippov
Remove declarations of the internal mmu_helper functions from the cpu.h, make these functions static and shuffle them. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-10target/xtensa: get rid of centralized SR propertiesMax Filippov
SR numbers are not unique: different Xtensa options may reuse SR number for different purposes. Introduce generic rsr/wsr functions and xsr template and use them instead of centralized SR access functions. Change prototypes of specific rsr/wsr functions to match XtensaOpcodeOp and use them instead of centralized SR access functions. Put xtensa option that introduces SR into the second opcode description parameter and use it to test for rsr/wsr/xsr opcode validity. Extract SR and UR names for the xtensa_cpu_dump_state from libisa. Merge SRs and URs in the dump. Register names of used SR/UR in init_libisa and use these names for TCG globals referencing these SR/UR. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-05-10target/xtensa: Convert to CPUClass::tlb_fillRichard Henderson
Cc: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-04-18qom/cpu: Simplify how CPUClass:cpu_dump_state() printsMarkus Armbruster
CPUClass method dump_statistics() takes an fprintf()-like callback and a FILE * to pass to it. Most callers pass fprintf() and stderr. log_cpu_state() passes fprintf() and qemu_log_file. hmp_info_registers() passes monitor_fprintf() and the current monitor cast to FILE *. monitor_fprintf() casts it right back, and is otherwise identical to monitor_printf(). The callback gets passed around a lot, which is tiresome. The type-punning around monitor_fprintf() is ugly. Drop the callback, and call qemu_fprintf() instead. Also gets rid of the type-punning, since qemu_fprintf() takes NULL instead of the current monitor cast to FILE *. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190417191805.28198-15-armbru@redhat.com>
2019-04-18target: Clean up how the dump_mmu() printMarkus Armbruster
The various dump_mmu() take an fprintf()-like callback and a FILE * to pass to it, and so do their helper functions. Passing around callback and argument is rather tiresome. Most dump_mmu() are called only by the target's hmp_info_tlb(). These all pass monitor_printf() cast to fprintf_function and the current monitor cast to FILE *. SPARC's dump_mmu() gets also called from target/sparc/ldst_helper.c a few times #ifdef DEBUG_MMU. These calls pass fprintf() and stdout. The type-punning is technically undefined behaviour, but works in practice. Clean up: drop the callback, and call qemu_printf() instead. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190417191805.28198-11-armbru@redhat.com>
2019-04-18target: Simplify how the TARGET_cpu_list() printMarkus Armbruster
The various TARGET_cpu_list() take an fprintf()-like callback and a FILE * to pass to it. Their callers (vl.c's main() via list_cpus(), bsd-user/main.c's main(), linux-user/main.c's main()) all pass fprintf() and stdout. Thus, the flexibility provided by the (rather tiresome) indirection isn't actually used. Drop the callback, and call qemu_printf() instead. Calling printf() would also work, but would make the code unsuitable for monitor context without making it simpler. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190417191805.28198-10-armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-02-28target/xtensa: implement PREFCTL SRMax Filippov
Cache prefetch option adds an unprivileged SR PREFCTL. Add trivial implementation for this SR. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-28target/xtensa: prioritize load/store in FLIX bundlesMax Filippov
Load/store opcodes may raise MMU exceptions. Normally exceptions should be checked in priority order before any actual operations, but since MMU exceptions are tightly coupled with actual memory access, there's currently no way to do it. Approximate this behavior by executing all load, then all store, and then all other opcodes in the FLIX bundles. Use opcode dependency mechanism to express ordering. Mark load/store opcodes with XTENSA_OP_{LOAD,STORE} flags. Newer libisa has classifier functions that can tell whether opcode is a load or store, but this information is not available in the existing overlays. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-28target/xtensa: reorganize register handling in translatorsMax Filippov
To support circular register dependencies in FLIX bundles opcode inputs and outputs must be separate and adjustable. Circular dependencies can be broken by making temporary copies of opcode inputs and substituting them into the arguments array instead of the original registers. E.g. the circular register dependency in the following bundle: { mov a2, a3 ; mov a3, a2 } can be resolved by making copy a2' = a2 and substituting it as input argument of the second opcode: { mov a2, a3 ; mov a3, a2' } Change opcode translator prototype to accept OpcodeArg array as argument. For each register argument initialize OpcodeArg::{in,out} with TCGv_* of the respective register. Don't explicitly use cpu_R in the opcode translators, use OpcodeArg::{in,out} instead. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-28target/xtensa: move WINDOW_BASE SR update to postprocessingMax Filippov
Opcodes that modify WINDOW_BASE SR don't have dependency on opcodes that use windowed registers. If such opcodes are combined in a single instruction they may not be correctly ordered. Instead of adding said dependency use temporary register to store changed WINDOW_BASE value and do actual register window rotation as a postprocessing step. Not all opcodes that change WINDOW_BASE need this: retw, rfwo and rfwu are also jump opcodes, so they are guaranteed to be translated last and thus will not affect other opcodes in the same instruction. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-28target/xtensa: add generic instruction post-processingMax Filippov
Some opcodes may need additional actions at every exit from the translated instruction or may need to amend TB exit slots available to jumps generated for the instruction. Add gen_postprocess function and call it from the gen_jump_slot and from the disas_xtensa_insn. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-28target/xtensa: sort FLIX instruction opcodesMax Filippov
Opcodes in different slots may read and write same resources (registers, states). In the absence of resource dependency loops it must be possible to sort opcodes to avoid interference. Record resources used by each opcode in the bundle. Build opcode dependency graph and use topological sort to order its nodes. In case of success translate opcodes in sort order. In case of failure report and raise invalid opcode exception. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-18target/xtensa: allow multiple names for single opcodeMax Filippov
There are opcodes that differ only in encoding or possible range of immediate arguments. Allow multiple names for single opcode translation table entry to reduce code duplication in that case. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-18target/xtensa: don't require opcode table sortingMax Filippov
Requirement for alphabetical opcode sorting in opcode tables is awkward and does not allow sharing implementation between multiple opcodes. Use hash tables to find opcodes by name. Move implementation from the translate.c to the helper.c to its only user and remove declaration from the cpu.h Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-18target/xtensa: move xtensa_finalize_config to xtensa_core_class_initMax Filippov
Don't run xtensa_finalize_config at the time of core registration, instead run it at the CPU class initialization. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-10target/xtensa: don't specify windowed registers manuallyMax Filippov
Use libisa to extract whether opcode uses windowed registers and construct mask based on that. This only leaves special case for the 'entry' opcode, as it needs to probe a register dynamically. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-01-28target/xtensa: expose core runstall as an IRQ lineMax Filippov
Runstall signal looks very much like a level-triggered IRQ line. Provide xtensa_get_runstall function that returns runstall IRQ. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-01-28target/xtensa: rearrange access to external interruptsMax Filippov
Replace xtensa_get_extint that returns single external IRQ descriptor with xtensa_get_extints that returns a vector of all external IRQs. Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-01-28target/xtensa: drop function xtensa_timer_irqMax Filippov
It's a one-liner used in a single place, move its implementation there and remove its declaration. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-01-11target/xtensa: rework zero overhead loops implementationMax Filippov
Don't invalidate TB with the end of zero overhead loop when LBEG or LEND change. Instead encode the distance from the start of the page where the TB starts to the LEND in the TB cs_base and generate loopback code when the next PC matches encoded LEND. Distance to a destination within the same page and up to a maximum instruction length into the next page is encoded literally, otherwise it's zero. The distance from LEND to LBEG is also encoded in the cs_base: it's encoded literally when less than 256 or as 0 otherwise. This allows for TB chaining for the loopback branch at the end of a loop for the most common loop sizes. With this change the resulting emulation speed is about 10% higher in softmmu mode on uClibc-ng and LTP tests. Emulation speed in linux user mode is a few percent lower because there's no direct TB chaining between different memory pages. Testing with lower limit on direct TB chaining range shows gradual slowdown to ~15% for the block size of 64 bytes and ~50% for the block size of 32 bytes. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-01target/xtensa: extract test for cpdisabled exceptionMax Filippov
- add XtensaOpcodeOps::coprocessor with bitmask of coprocessors used by the instruction; - replace coprocessor id parameter of gen_check_cpenable with the bitmask of used coprocessors; - collect coprocessor IDs used by an instruction in the disassembly loop; - put test for coprocessor disabled exception after the alloca test; Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-10-01target/xtensa: extract test for window overflow exceptionMax Filippov
- add ps.callinc to the TB flags, that allows testing all instructions for window overflow statically; - drop gen_window_check* functions; replace them with get_window_check that accepts bitmask of used registers; - add XtensaOpcodeOps::test_overflow that returns bitmask of implicitly used registers; use it for entry and call{,x}{4,8,12}; - drop window overflow test from the entry helper; - drop parameter 0 from translate_[di]cache and use translate_nop for d/i cache opcodes that don't need memory accessibility check; - add bitmask XtensaOpcodeOps::windowed_register_op that marks opcode arguments that refer to windowed registers; - translate windowed_register_op mask to a mask of actually used registers in the disassembly loop; - add check for window overflow right after the check for debug exception; Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-10-01target/xtensa: extract test for an illegal instructionMax Filippov
- TB flags: add XTENSA_TBFLAG_CWOE that corresponds to the architectural CWOE state; - entry: move CWOE check from the helper to the test_ill_entry; - retw: move CWOE check from the helper to the test_ill_retw; - separate instruction disassembly loop and translation loop; save disassembly results in local array; Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-09-17target/xtensa: convert to do_transaction_failedMax Filippov
Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-08-19target/xtensa: clean up gdbstub register handlingMax Filippov
- move register counting to xtensa/gdbstub.c - add symbolic names for register types and flags from GDB and use them in register counting and access functions. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-06-30target/xtensa: check zero overhead loop alignmentMax Filippov
ISA book documents that the first instruction of zero overhead loop must fit completely into naturally aligned region of an instruction fetch unit size. Check that condition and log a message if it's violated. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-03-19cpu: get rid of unused cpu_init() definesIgor Mammedov
cpu_init(cpu_model) were replaced by cpu_create(cpu_type) so no users are left, remove it. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Acked-by: David Gibson <david@gibson.dropbear.id.au> (ppc) Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> Message-Id: <1518000027-274608-6-git-send-email-imammedo@redhat.com> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-03-19cpu: add CPU_RESOLVING_TYPE macroIgor Mammedov
it will be used for providing to cpu name resolving class for parsing cpu model for system and user emulation code. Along with change add target to null-machine tests, so that when switch to CPU_RESOLVING_TYPE happens, it would ensure that null-machine usecase still works. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Laurent Vivier <laurent@vivier.eu> (m68k) Acked-by: David Gibson <david@gibson.dropbear.id.au> (ppc) Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> (tricore) Message-Id: <1518000027-274608-4-git-send-email-imammedo@redhat.com> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> [ehabkost: Added macro to riscv too] Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-03-16target/xtensa: add linux-user supportMax Filippov
Import list of syscalls from the kernel source. Conditionalize code/data that is only used with softmmu. Implement exception handlers. Implement signal hander (only the core registers for now, no coprocessors or TIE). Cc: Riku Voipio <riku.voipio@iki.fi> Cc: Laurent Vivier <laurent@vivier.eu> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-03-13target/xtensa: support MTTCGMax Filippov
- emit TCG barriers for MEMW, EXTW, S32RI and L32AI; - do atomic_cmpxchg_i32 for S32C1I. Cc: Emilio G. Cota <cota@braap.org> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>