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2016-05-21lib/GCD.c: use binary GCD algorithm instead of EuclideanZhaoxiu Zeng
The binary GCD algorithm is based on the following facts: 1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2) 2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b) 3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b) Even on x86 machines with reasonable division hardware, the binary algorithm runs about 25% faster (80% the execution time) than the division-based Euclidian algorithm. On platforms like Alpha and ARMv6 where division is a function call to emulation code, it's even more significant. There are two variants of the code here, depending on whether a fast __ffs (find least significant set bit) instruction is available. This allows the unpredictable branches in the bit-at-a-time shifting loop to be eliminated. If fast __ffs is not available, the "even/odd" GCD variant is used. I use the following code to benchmark: #include <stdio.h> #include <stdlib.h> #include <stdint.h> #include <string.h> #include <time.h> #include <unistd.h> #define swap(a, b) \ do { \ a ^= b; \ b ^= a; \ a ^= b; \ } while (0) unsigned long gcd0(unsigned long a, unsigned long b) { unsigned long r; if (a < b) { swap(a, b); } if (b == 0) return a; while ((r = a % b) != 0) { a = b; b = r; } return b; } unsigned long gcd1(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; b >>= __builtin_ctzl(b); for (;;) { a >>= __builtin_ctzl(a); if (a == b) return a << __builtin_ctzl(r); if (a < b) swap(a, b); a -= b; } } unsigned long gcd2(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; r &= -r; while (!(b & r)) b >>= 1; for (;;) { while (!(a & r)) a >>= 1; if (a == b) return a; if (a < b) swap(a, b); a -= b; a >>= 1; if (a & r) a += b; a >>= 1; } } unsigned long gcd3(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; b >>= __builtin_ctzl(b); if (b == 1) return r & -r; for (;;) { a >>= __builtin_ctzl(a); if (a == 1) return r & -r; if (a == b) return a << __builtin_ctzl(r); if (a < b) swap(a, b); a -= b; } } unsigned long gcd4(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; r &= -r; while (!(b & r)) b >>= 1; if (b == r) return r; for (;;) { while (!(a & r)) a >>= 1; if (a == r) return r; if (a == b) return a; if (a < b) swap(a, b); a -= b; a >>= 1; if (a & r) a += b; a >>= 1; } } static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = { gcd0, gcd1, gcd2, gcd3, gcd4, }; #define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0])) #if defined(__x86_64__) #define rdtscll(val) do { \ unsigned long __a,__d; \ __asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \ (val) = ((unsigned long long)__a) | (((unsigned long long)__d)<<32); \ } while(0) static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long), unsigned long a, unsigned long b, unsigned long *res) { unsigned long long start, end; unsigned long long ret; unsigned long gcd_res; rdtscll(start); gcd_res = gcd(a, b); rdtscll(end); if (end >= start) ret = end - start; else ret = ~0ULL - start + 1 + end; *res = gcd_res; return ret; } #else static inline struct timespec read_time(void) { struct timespec time; clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time); return time; } static inline unsigned long long diff_time(struct timespec start, struct timespec end) { struct timespec temp; if ((end.tv_nsec - start.tv_nsec) < 0) { temp.tv_sec = end.tv_sec - start.tv_sec - 1; temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec; } else { temp.tv_sec = end.tv_sec - start.tv_sec; temp.tv_nsec = end.tv_nsec - start.tv_nsec; } return temp.tv_sec * 1000000000ULL + temp.tv_nsec; } static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long), unsigned long a, unsigned long b, unsigned long *res) { struct timespec start, end; unsigned long gcd_res; start = read_time(); gcd_res = gcd(a, b); end = read_time(); *res = gcd_res; return diff_time(start, end); } #endif static inline unsigned long get_rand() { if (sizeof(long) == 8) return (unsigned long)rand() << 32 | rand(); else return rand(); } int main(int argc, char **argv) { unsigned int seed = time(0); int loops = 100; int repeats = 1000; unsigned long (*res)[TEST_ENTRIES]; unsigned long long elapsed[TEST_ENTRIES]; int i, j, k; for (;;) { int opt = getopt(argc, argv, "n:r:s:"); /* End condition always first */ if (opt == -1) break; switch (opt) { case 'n': loops = atoi(optarg); break; case 'r': repeats = atoi(optarg); break; case 's': seed = strtoul(optarg, NULL, 10); break; default: /* You won't actually get here. */ break; } } res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops); memset(elapsed, 0, sizeof(elapsed)); srand(seed); for (j = 0; j < loops; j++) { unsigned long a = get_rand(); /* Do we have args? */ unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand(); unsigned long long min_elapsed[TEST_ENTRIES]; for (k = 0; k < repeats; k++) { for (i = 0; i < TEST_ENTRIES; i++) { unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]); if (k == 0 || min_elapsed[i] > tmp) min_elapsed[i] = tmp; } } for (i = 0; i < TEST_ENTRIES; i++) elapsed[i] += min_elapsed[i]; } for (i = 0; i < TEST_ENTRIES; i++) printf("gcd%d: elapsed %llu\n", i, elapsed[i]); k = 0; srand(seed); for (j = 0; j < loops; j++) { unsigned long a = get_rand(); unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand(); for (i = 1; i < TEST_ENTRIES; i++) { if (res[j][i] != res[j][0]) break; } if (i < TEST_ENTRIES) { if (k == 0) { k = 1; fprintf(stderr, "Error:\n"); } fprintf(stderr, "gcd(%lu, %lu): ", a, b); for (i = 0; i < TEST_ENTRIES; i++) fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n"); } } if (k == 0) fprintf(stderr, "PASS\n"); free(res); return 0; } Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got: zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 10174 gcd1: elapsed 2120 gcd2: elapsed 2902 gcd3: elapsed 2039 gcd4: elapsed 2812 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9309 gcd1: elapsed 2280 gcd2: elapsed 2822 gcd3: elapsed 2217 gcd4: elapsed 2710 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9589 gcd1: elapsed 2098 gcd2: elapsed 2815 gcd3: elapsed 2030 gcd4: elapsed 2718 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9914 gcd1: elapsed 2309 gcd2: elapsed 2779 gcd3: elapsed 2228 gcd4: elapsed 2709 PASS [akpm@linux-foundation.org: avoid #defining a CONFIG_ variable] Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com> Signed-off-by: George Spelvin <linux@horizon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-13MIPS: Add probing & defs for VZ & guest featuresJames Hogan
Add a few new cpu-features.h definitions for VZ sub-features, namely the existence of the CP0_GuestCtl0Ext, CP0_GuestCtl1, and CP0_GuestCtl2 registers, and support for GuestID to dialias TLB entries belonging to different guests. Also add certain features present in the guest, with the naming scheme cpu_guest_has_*. These are added separately to the main options bitfield since they generally parallel similar features in the root context. A few of these (FPU, MSA, watchpoints, perf counters, CP0_[X]ContextConfig registers, MAAR registers, and probably others in future) can be dynamically configured in the guest context, for which the cpu_guest_has_dyn_* macros are added. [ralf@linux-mips.org: Resolve merge conflict.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13231/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Add perf counter featureJames Hogan
Add CPU feature for standard MIPS r2 performance counters, as determined by the Config1.PC bit. Both perf_events and oprofile probe this bit, so lets combine the probing and change both to use cpu_has_perf. This will also be used for VZ support in KVM to know whether performance counters exist which can be exposed to guests. [ralf@linux-mips.org: resolve conflict.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Robert Richter <rric@kernel.org> Cc: linux-mips@linux-mips.org Cc: oprofile-list@lists.sf.net Patchwork: https://patchwork.linux-mips.org/patch/13226/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Add defs & probing of [X]ContextConfigJames Hogan
The CP0_[X]ContextConfig registers are present if CP0_Config3.CTXTC or CP0_Config3.SM are set, and provide more control over which bits of CP0_[X]Context are set to the faulting virtual address on a TLB exception. KVM/VZ will need to be able to save and restore these registers in the guest context, so add the relevant definitions and probing of the ContextConfig feature in the root context first. [ralf@linux-mips.org: resolve merge conflict.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13225/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Add defs & probing of BadInstr[P] registersJames Hogan
The optional CP0_BadInstr and CP0_BadInstrP registers are written with the encoding of the instruction that caused a synchronous exception to occur, and the prior branch instruction if in a delay slot. These will be useful for instruction emulation in KVM, and especially for VZ support where reading guest virtual memory is a bit more awkward. Add CPU option numbers and cpu_has_* definitions to indicate the presence of each registers, and add code to probe for them using bits in the CP0_Config3 register. [ralf@linux-mips.org: resolve merge conflict.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13224/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Add defs & probing of extended CP0_EBaseJames Hogan
The CP0_EBase register may optionally have a write gate (WG) bit to allow the upper bits to be written, i.e. bits 31:30 on MIPS32 since r3 (to allow for an exception base outside of KSeg0/KSeg1 when segmentation control is in use) and bits 63:30 on MIPS64 (which also implies the extension of CP0_EBase to 64 bits long). The presence of this feature will need to be known about for VZ support in order to correctly save and restore all the bits of the guest CP0_EBase register, so add CPU feature definition and probing for this feature. Probing the WG bit on MIPS64 can be a bit fiddly, since 64-bit COP0 register access instructions were UNDEFINED for 32-bit registers prior to MIPS r6, and it'd be nice to be able to probe without clobbering the existing state, so there are 3 potential paths: - If we do a 32-bit read of CP0_EBase and the WG bit is already set, the register must be 64-bit. - On MIPS r6 we can do a 64-bit read-modify-write to set CP0_EBase.WG, since the upper bits will read 0 and be ignored on write if the register is 32-bit. - On pre-r6 cores, we do a 32-bit read-modify-write of CP0_EBase. This avoids the potentially UNDEFINED behaviour, but will clobber the upper 32-bits of CP0_EBase if it isn't a simple sign extension (which also requires us to ensure BEV=1 or modifying the exception base would be UNDEFINED too). It is hopefully unlikely a bootloader would set up CP0_EBase to a 64-bit segment and leave WG=0. [ralf@linux-mips.org: Resolved merge conflict.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Tested-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13223/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Separate XPA CPU feature into LPA and MVHJames Hogan
XPA (eXtended Physical Addressing) should be detected as a combination of two architectural features: - Large Physical Address (as per Config3.LPA). With XPA this will be set on MIPS32r5 cores, but it may also be set for MIPS64r2 cores too. - MTHC0/MFHC0 instructions (as per Config5.MVH). With XPA this will be set, but it may also be set in VZ guest context even when Config3.LPA in the guest context has been cleared by the hypervisor. As such, XPA is only usable if both bits are set. Update CPU features to separate these two features, with cpu_has_xpa requiring both to be set. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Joshua Kinard <kumba@gentoo.org> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/13112/ Signed-off-by: Paul Burton <paul.burton@imgtec.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Loongson-3: Fast TLB refill handlerHuacai Chen
Loongson-3A R2 has pwbase/pwfield/pwsize/pwctl registers in CP0 (this is very similar to HTW) and lwdir/lwpte/lddir/ldpte instructions which can be used for fast TLB refill. [ralf@linux-mips.org: Resolve conflict.] Signed-off-by: Huacai Chen <chenhc@lemote.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Steven J . Hill <sjhill@realitydiluted.com> Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12754/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Detect DSP v3 supportZubair Lutfullah Kakakhel
DSPv3 is supported on all MIPSr6 systems which indicate support for DSPv2. This doesn't require any changes to the kernel's handling of DSP resources. The patch is to detect support and indicate it in /proc/cpuinfo DSP v3 introduces a new instruction BPOSGE32C Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com> Reviewed-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12918/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13MIPS: Detect MIPSr6 Virtual Processor supportPaul Burton
MIPSr6 introduces support for "Virtual Processors", which are conceptually similar to VPEs from the now-deprecated MT ASE. Detect whether the system supports VPs using the VP bit in Config5, adding cpu_has_vp for use by later patches. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Maciej W. Rozycki <macro@imgtec.com> Cc: Joshua Kinard <kumba@gentoo.org> Cc: Steven J. Hill <sjhill@realitydiluted.com> Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12327/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-19MIPS: Define the legacy-NaN and 2008-NaN featuresMaciej W. Rozycki
Allocate CPU option bits and define macros for the legacy-NaN and 2008-NaN IEEE Std 754 MIPS architecture features. Unconditionally mark the legacy-NaN feature as present across hardware and emulated floating-point configurations. Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Fortune <Matthew.Fortune@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/11475/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-11-11MIPS: Allow RIXI for 32-bit kernels on MIPS64Paul Burton
Commit a68d09a156b2 ("MIPS: Don't use RI/XI with 32-bit kernels on 64-bit CPUs") prevented use of RIXI on MIPS64 systems, stating that the "TLB handlers cannot handle this case". What they actually couldn't handle was cases where there were less fill bits in the Entry{Lo,Hi} registers than bits used by software in PTEs. The handlers can now deal with this case, so enable RIXI for MIPS32 kernels on MIPS64 systems. Note that beyond the obvious benefits provided by having RIXI on such systems, this is required for systems implementing MIPSr6 where RIXI cannot be disabled. This reverts commit a68d09a156b2 ("MIPS: Don't use RI/XI with 32-bit kernels on 64-bit CPUs"). Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Joshua Kinard <kumba@gentoo.org> Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Cc: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-kernel@vger.kernel.org Cc: James Hogan <james.hogan@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Patchwork: https://patchwork.linux-mips.org/patch/11219/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-09-22MIPS: cpu-features: Add cpu_has_ftlbJames Hogan
Add cpu_has_ftlb, which specifies that an FTLB is present in addition to the VTLB, probed based on whether Config.MT == 4 (rather than 1 for standard JTLB). This is necessary since MIPS release 6 removes Config4.MMUExtDef, so the presence of the FTLB fields in Config4 must be determined from Config.MT instead. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/11159/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-09-03MIPS: Probe for small (1KiB) page supportJames Hogan
Probe Config3 for small page support. This will be useful to give clues as to whether the PageGrain register exists. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10722/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-06-21MIPS: R12000: Enable branch prediction global historyJoshua Kinard
The R12000 added a new feature to enhance branch prediction called "global history". Per the Vr10000 Series User Manual (U10278EJ4V0UM), Coprocessor 0, Diagnostic Register (22): """ If bit 26 is set, branch prediction uses all eight bits of the global history register. If bit 26 is not set, then bits 25:23 specify a count of the number of bits of global history to be used. Thus if bits 26:23 are all zero, global history is disabled. The global history contains a record of the taken/not-taken status of recently executed branches, and when used is XOR'ed with the PC of a branch being predicted to produce a hashed value for indexing the BPT. Some programs with small "working set of conditional branches" benefit significantly from the use of such hashing, some see slight performance degradation. """ This patch enables global history on R12000 CPUs and up by setting bit 26 in the branch prediction diagnostic register (CP0 $22) to '1'. Bits 25:23 are left alone so that all eight bits of the global history register are available for branch prediction. Signed-off-by: Joshua Kinard <kumba@gentoo.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-13Merge branch '4.0-fixes' into mips-for-linux-nextRalf Baechle
2015-04-10MIPS: Fix cpu_has_mips_r2_exec_hazard.Ralf Baechle
Returns a non-zero value if the current processor implementation requires an IHB instruction to deal with an instruction hazard as per MIPS R2 architecture specification, zero otherwise. For a discussion, see http://patchwork.linux-mips.org/patch/9539/. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-07MIPS: Correct FP ISA requirementsMaciej W. Rozycki
Correct ISA requirements for floating-point instructions: * the CU3 exception signifies a real COP3 instruction in MIPS I & II, * the BC1FL and BC1TL instructions are not supported in MIPS I, * the SQRT.fmt instructions are indeed supported in MIPS II, * the LDC1 and SDC1 instructions are indeed supported in MIPS32r1, * the CEIL.W.fmt, FLOOR.W.fmt, ROUND.W.fmt and TRUNC.W.fmt instructions are indeed supported in MIPS32, * the CVT.L.fmt and CVT.fmt.L instructions are indeed supported in MIPS32r2 and MIPS32r6, * the CEIL.L.fmt, FLOOR.L.fmt, ROUND.L.fmt and TRUNC.L.fmt instructions are indeed supported in MIPS32r2 and MIPS32r6, * the RSQRT.fmt and RECIP.fmt instructions are indeed supported in MIPS64r1, Also simplify conditionals for MIPS III and MIPS IV FPU instructions and the handling of the MOVCI minor opcode. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9700/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-07MIPS: Correct `nofpu' non-functionalityMaciej W. Rozycki
The `cpu_has_fpu' feature flag must not be hardcoded to 1 or the `nofpu' kernel option will be ignored. Remove any such overrides and add a cautionary note. Hardcoding to 0 is fine for FPU-less platforms. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9694/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31MIPS: Add arch CDMM definitions and probingJames Hogan
Add architectural definitions and probing for the MIPS Common Device Memory Map (CDMM) region. When supported and enabled at a particular physical address, this region allows some number of per-CPU devices to be discovered and controlled via MMIO. A bit exists in Config3 to determine whether the feature is present, and a CDMMBase CP0 register allows the region to be enabled at a particular physical address. [ralf@linux-mips.org: Sort conflict with other patches.] Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9178/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-19MIPS: Add support for XPA.Steven J. Hill
Add support for extended physical addressing (XPA) so that 32-bit platforms can access equal to or greater than 40 bits of physical addresses. NOTE: 1) XPA and EVA are not the same and cannot be used simultaneously. 2) If you configure your kernel for XPA, the PTEs and all address sizes become 64-bit. 3) Your platform MUST have working HIGHMEM support. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9355/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-17MIPS: Handle MIPS IV, V and R2 FPU instructions on MIPS R6 as wellMarkos Chandras
MIPS R2 FPU instructions are also present in MIPS R6 so amend the preprocessor definitions to take MIPS R6 into consideration. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17MIPS: Add LLB bit and related feature for the Config 5 CP0 registerMarkos Chandras
The LLBIT (bit 4) in the Config5 CP0 register indicates the software availability of the Load-Linked bit. This bit is only set by hardware and it has the following meaning: 0: LLB functionality is not supported 1: LLB functionality is supported. The following feature are also supported: - ERETNC instruction. Similar to ERET but it does not clear the LLB bit in the LLAddr register. - CP0 LLAddr/LLB bit must be set - LLbit is software accessible through the LLAddr[0] This will be used later on to emulate R2 LL/SC instructions. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17MIPS: kernel: proc: Add MIPS R6 support to /proc/cpuinfoMarkos Chandras
Print 'mips64r6' and/or 'mips32r6' if the kernel is running on a MIPS R6 core. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2015-02-17MIPS: asm: cpu: Add MIPSR6 ISA definitionsLeonid Yegoshin
Add MIPS R6 to the ISA definitions Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2014-11-24MIPS: detect presence of the FRE & UFR bitsPaul Burton
Detect the presence of the Config5 FRE & UFE bits, as indicated by the FREP bit in FPIR. Record this as a CPU option bit, and provide a cpu_has_fre macro to ease checking of that option bit. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/7678/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-09-22MIPS: Use WSBH/DSBH/DSHD on Loongson 3AChen Jie
Signed-off-by: chenj <chenj@lemote.com> Cc: linux-mips@linux-mips.org Cc: chenhc@lemote.com Patchwork: https://patchwork.linux-mips.org/patch/7542/ Patchwork: https://patchwork.linux-mips.org/patch/7550/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-01MIPS: detect presence of MAARsPaul Burton
Detect the presence of MAAR using the MRP bit in Config5, and record that presence using a CPU option bit. A cpu_has_maar macro will then allow code to conditionalise upon the presence of MAARs. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7330/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-01MIPS: Add new option for unique RI/XI exceptionsLeonid Yegoshin
MIPSr5 added support for unique exception codes for the Read-Inhibit and Execute-Inhibit exceptions. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7338/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-08-01MIPS: cpu: Add new cpu option for Hardware Table Walker.Markos Chandras
Moreover, report hardware page table walker support as 'htw' in the ASE list of /proc/cpuinfo, if the core implements this feature. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7334/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-30MIPS: Don't use RI/XI with 32-bit kernels on 64-bit CPUsDavid Daney
The TLB handlers cannot handle this case, so disable it for now. Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com> Cc: linux-mips@linux-mips.org Cc: James Hogan <james.hogan@imgtec.com> Cc: kvm@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/7007/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-05-21MIPS: math-emu: Remove most ifdefery.Ralf Baechle
Most of these tests should be runtime tests. This also finally means that on a MIPS III systems MIPS IV opcodes are going to result in an exception as they're supposed to. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-03-26MIPS: asm: cpu: Add cpu flag for Enhanced Virtual AddressingMarkos Chandras
The MIPS *Aptiv family uses bit 28 in Config5 CP0 register to indicate whether the core supports EVA or not. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
2014-03-26MIPS: Detect the MSA ASEPaul Burton
This patch adds support for probing the MSAP bit within the Config3 register in order to detect the presence of the MSA ASE. Presence of the ASE will be indicated in /proc/cpuinfo. The value of the MSA implementation register will be displayed at boot to aid debugging and verification of a correct setup, as is done for the FPU. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6430/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-01-22MIPS: features: Add initial support for Segmentation Control registersSteven J. Hill
MIPS32R3 introduced a new set of Segmentation Control registers which increase the flexibility of the segmented-based memory scheme. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6131/
2014-01-22MIPS: features: Add initial support for TLBINVF capable coresLeonid Yegoshin
New Aptiv cores support the TLBINVF instruction for flushing the VTLB. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6130/
2013-09-24MIPS: cpu-features.h: s/MIPS53/MIPS64/Maciej W. Rozycki
No support for MIPS53 processors yet. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5876/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-09-17MIPS: Optimize current_cpu_type() for better code.Ralf Baechle
o Move current_cpu_type() to a separate header file o #ifdefing on supported CPU types lets modern GCC know that certain code in callers may be discarded ideally turning current_cpu_type() into a function returning a constant. o Use current_cpu_type() rather than direct access to struct cpuinfo_mips. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5833/
2013-08-05MIPS: oprofile: Fix BUG due to smp_processor_id() in preemptible code.Ralf Baechle
current_cpu_type() is not preemption-safe. If CONFIG_PREEMPT is enabled then mipsxx_reg_setup() can be called from preemptible state. Added get_cpu()/put_cpu() pair to make it preemption-safe. This was found while testing oprofile with CONFIG_DEBUG_PREEMPT enable. /usr/zntestsuite # opcontrol --init /usr/zntestsuite # opcontrol --setup --event=L2_CACHE_ACCESSES:500 --event=L2_CACHE_MISSES:500 --no-vmlinux /usr/zntestsuite # opcontrol --start Using 2.6+ OProfile kernel interface. BUG: using smp_processor_id() in preemptible [00000000] code: oprofiled/1362 caller is mipsxx_reg_setup+0x11c/0x164 CPU: 0 PID: 1362 Comm: oprofiled Not tainted 3.10.4 #18 Stack : 00000006 70757465 00000000 00000000 00000000 00000000 80b173f6 00000037 80b10000 00000000 80b21614 88f5a220 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 89c49c00 89c49c2c 80721254 807b7927 8012c1d0 80b10000 80721254 00000000 00000552 88f5a220 80b1335c 807b78e6 89c49ba8 ... Call Trace: [<801099a4>] show_stack+0x64/0x7c [<80665520>] dump_stack+0x20/0x2c [<803a2250>] debug_smp_processor_id+0xe0/0xf0 [<8052df24>] mipsxx_reg_setup+0x11c/0x164 [<8052cd70>] op_mips_setup+0x24/0x4c [<80529cfc>] oprofile_setup+0x5c/0x12c [<8052b9f8>] event_buffer_open+0x78/0xf8 [<801c3150>] do_dentry_open.isra.15+0x2b8/0x3b0 [<801c3270>] finish_open+0x28/0x4c [<801d49b8>] do_last.isra.41+0x2cc/0xd00 [<801d54a0>] path_openat+0xb4/0x4c4 [<801d5c44>] do_filp_open+0x3c/0xac [<801c4744>] do_sys_open+0x110/0x1f4 [<8010f47c>] stack_done+0x20/0x44 Bug reported and original patch by Jerin Jacob <jerinjacobk@gmail.com>. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Jerin Jacob <jerinjacobk@gmail.com>
2013-07-01MIPS: Cleanup indentation and whitespaceTony Wu
Signed-off-by: Tony Wu <tung7970@gmail.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5536/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-01MIPS: Only set cpu_has_mmips if SYS_SUPPORTS_MICROMIPSDavid Daney
As Jonas Gorske said in his patch: Disable cpu_has_mmips for everything but SEAD3 and MALTA. Most of these platforms are from before the micromips introduction, so they are very unlikely to implement it. Reduces an -Os compiled, uncompressed kernel image by 8KiB for BCM63XX. This patch taks a different approach than his, we gate the runtime test for microMIPS by the config symbol SYS_SUPPORTS_MICROMIPS. Signed-off-by: David Daney <david.daney@cavium.com> Cc: Jonas Gorski <jogo@openwrt.org> Cc: Steven J. Hill <Steven.Hill@imgtec.com> Acked-by: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5327/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-01MIPS: Get rid of MIPS I flag and test macros.Ralf Baechle
MIPS I is the ancestor of all MIPS ISA and architecture variants. Anything ever build in the MIPS empire is either MIPS I or at least contains MIPS I. If it's running Linux, that is. So there is little point in having cpu_has_mips_1 because it will always evaluate as true - though usually only at runtime. Thus there is no point in having the MIPS_CPU_ISA_I ISA flag, so get rid of it. Little complication: traps.c was using a test for a pure MIPS I ISA as a test for an R3000-style cp0. To deal with that, use a check for cpu_has_3kex or cpu_has_4kex instead. cpu_has_3kex is a new macro. At the moment its default implementation is !cpu_has_4kex but this may eventually change if Linux is ever going to support the oddball MIPS processors R6000 and R8000 so users of either of these macros should not make any assumptions. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Patchwork: https://patchwork.linux-mips.org/patch/5551/
2013-05-07MIPS: Build uasm-generated code only once to avoid CPU Hotplug problemHuacai Chen
This and the next patch resolve memory corruption problems while CPU hotplug. Without these patches, memory corruption can triggered easily as below: On a quad-core MIPS platform, use "spawn" of UnixBench-5.1.3 (http:// code.google.com/p/byte-unixbench/) and a CPU hotplug script like this (hotplug.sh): while true; do echo 0 >/sys/devices/system/cpu/cpu1/online echo 0 >/sys/devices/system/cpu/cpu2/online echo 0 >/sys/devices/system/cpu/cpu3/online sleep 1 echo 1 >/sys/devices/system/cpu/cpu1/online echo 1 >/sys/devices/system/cpu/cpu2/online echo 1 >/sys/devices/system/cpu/cpu3/online sleep 1 done Run "hotplug.sh" and then run "spawn 10000", spawn will get segfault after a few minutes. This patch: Currently, clear_page()/copy_page() are generated by Micro-assembler dynamically. But they are unavailable until uasm_resolve_relocs() has finished because jump labels are illegal before that. Since these functions are shared by every CPU, we only call build_clear_page()/ build_copy_page() only once at boot time. Without this patch, programs will get random memory corruption (segmentation fault, bus error, etc.) while CPU Hotplug (e.g. one CPU is using clear_page() while another is generating it in cpu_cache_init()). For similar reasons we modify build_tlb_refill_handler()'s invocation. V2: 1, Rework the code to make CPU#0 can be online/offline. 2, Introduce cpu_has_local_ebase feature since some types of MIPS CPU need a per-CPU tlb_refill_handler(). Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Hongbing Hu <huhb@lemote.com> Acked-by: David Daney <david.daney@cavium.com> Patchwork: http://patchwork.linux-mips.org/patch/4994/ Acked-by: John Crispin <blogic@openwrt.org>
2013-02-21Merge branch 'mips-next-3.9' of ↵Ralf Baechle
git://git.linux-mips.org/pub/scm/john/linux-john into mips-for-linux-next
2013-02-19MIPS: Probe for and report hardware virtualization support.David Daney
The presence of the MIPS Virtualization Application-Specific Extension is indicated by CP0_Config3[23]. Probe for this and report it in /proc/cpuinfo. Signed-off-by: David Daney <david.daney@cavium.com> Patchwork: http://patchwork.linux-mips.org/patch/4904/ Signed-off-by: John Crispin <blogic@openwrt.org>
2013-02-16MIPS: Add support for the M14KEc core.Steven J. Hill
Signed-off-by: Steven J. Hill <sjhill@mips.com> Patchwork: http://patchwork.linux-mips.org/patch/4682/ Signed-off-by: John Crispin <blogic@openwrt.org>
2013-02-15MIPS: Add printing of ISA version in cpuinfo.Steven J. Hill
Display the MIPS ISA version release in the /proc/cpuinfo file. [ralf@linux-mips.org: Add support for MIPS I ... IV legacy architecture revisions. Also differenciate between MIPS32 and MIPS64 versions instead of lumping them together as just r1 and r2. Note to application programmers: this indicates the CPU's ISA level It does not imply the current execution environment does support it. For example an O32 application seeing "mips64r2" would still be restricted by by the execution environment to 32-bit - but the kernel could run mips64r2 code. The same for a 32-bit kernel running on a 64-bit processor. This field doesn't include ASEs or optional architecture modules nor other detailed flags such as the availability of an FPU.] Signed-off-by: Steven J. Hill <sjhill@mips.com> Cc: linux-mips@linux-mips.org Patchwork: http://patchwork.linux-mips.org/patch/4714/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-02-01MIPS: Whitespace cleanup.Ralf Baechle
Having received another series of whitespace patches I decided to do this once and for all rather than dealing with this kind of patches trickling in forever. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-11MIPS: Add detection of DSP ASE Revision 2.Steven J. Hill
[ralf@linux-mips.org: This patch really only detects the ASE and passes its existence on to userland via /proc/cpuinfo. The DSP ASE Rev 2. adds new resources but no resources that would need management by the kernel.] Signed-off-by: Steven J. Hill <sjhill@mips.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/4165/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-10-11MIPS: perf: Add cpu feature bit for PCI (performance counter interrupt)Al Cooper
The PCI (Program Counter Interrupt) bit in the "cause" register is mandatory for MIPS32R2 cores, but has also been added to some R1 cores (BMIPS5000). This change adds a cpu feature bit to make it easier to check for and use this feature. Signed-off-by: Al Cooper <alcooperx@gmail.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/4106/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>