diff options
Diffstat (limited to 'arch/loongarch/kernel/cpu-probe.c')
| -rw-r--r-- | arch/loongarch/kernel/cpu-probe.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/arch/loongarch/kernel/cpu-probe.c b/arch/loongarch/kernel/cpu-probe.c new file mode 100644 index 000000000000..255a09876ef2 --- /dev/null +++ b/arch/loongarch/kernel/cpu-probe.c @@ -0,0 +1,294 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Processor capabilities determination functions. + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/ptrace.h> +#include <linux/smp.h> +#include <linux/stddef.h> +#include <linux/export.h> +#include <linux/printk.h> +#include <linux/uaccess.h> + +#include <asm/cpu-features.h> +#include <asm/elf.h> +#include <asm/fpu.h> +#include <asm/loongarch.h> +#include <asm/pgtable-bits.h> +#include <asm/setup.h> + +/* Hardware capabilities */ +unsigned int elf_hwcap __read_mostly; +EXPORT_SYMBOL_GPL(elf_hwcap); + +/* + * Determine the FCSR mask for FPU hardware. + */ +static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_loongarch *c) +{ + unsigned long sr, mask, fcsr, fcsr0, fcsr1; + + fcsr = c->fpu_csr0; + mask = FPU_CSR_ALL_X | FPU_CSR_ALL_E | FPU_CSR_ALL_S | FPU_CSR_RM; + + sr = read_csr_euen(); + enable_fpu(); + + fcsr0 = fcsr & mask; + write_fcsr(LOONGARCH_FCSR0, fcsr0); + fcsr0 = read_fcsr(LOONGARCH_FCSR0); + + fcsr1 = fcsr | ~mask; + write_fcsr(LOONGARCH_FCSR0, fcsr1); + fcsr1 = read_fcsr(LOONGARCH_FCSR0); + + write_fcsr(LOONGARCH_FCSR0, fcsr); + + write_csr_euen(sr); + + c->fpu_mask = ~(fcsr0 ^ fcsr1) & ~mask; +} + +static inline void set_elf_platform(int cpu, const char *plat) +{ + if (cpu == 0) + __elf_platform = plat; +} + +/* MAP BASE */ +unsigned long vm_map_base; +EXPORT_SYMBOL_GPL(vm_map_base); + +static void cpu_probe_addrbits(struct cpuinfo_loongarch *c) +{ +#ifdef __NEED_ADDRBITS_PROBE + c->pabits = (read_cpucfg(LOONGARCH_CPUCFG1) & CPUCFG1_PABITS) >> 4; + c->vabits = (read_cpucfg(LOONGARCH_CPUCFG1) & CPUCFG1_VABITS) >> 12; + vm_map_base = 0UL - (1UL << c->vabits); +#endif +} + +static void set_isa(struct cpuinfo_loongarch *c, unsigned int isa) +{ + switch (isa) { + case LOONGARCH_CPU_ISA_LA64: + c->isa_level |= LOONGARCH_CPU_ISA_LA64; + fallthrough; + case LOONGARCH_CPU_ISA_LA32S: + c->isa_level |= LOONGARCH_CPU_ISA_LA32S; + fallthrough; + case LOONGARCH_CPU_ISA_LA32R: + c->isa_level |= LOONGARCH_CPU_ISA_LA32R; + break; + } +} + +static void cpu_probe_common(struct cpuinfo_loongarch *c) +{ + unsigned int config; + unsigned long asid_mask; + + c->options = LOONGARCH_CPU_CPUCFG | LOONGARCH_CPU_CSR | + LOONGARCH_CPU_TLB | LOONGARCH_CPU_VINT | LOONGARCH_CPU_WATCH; + + elf_hwcap |= HWCAP_LOONGARCH_CRC32; + + config = read_cpucfg(LOONGARCH_CPUCFG1); + if (config & CPUCFG1_UAL) { + c->options |= LOONGARCH_CPU_UAL; + elf_hwcap |= HWCAP_LOONGARCH_UAL; + } + + config = read_cpucfg(LOONGARCH_CPUCFG2); + if (config & CPUCFG2_LAM) { + c->options |= LOONGARCH_CPU_LAM; + elf_hwcap |= HWCAP_LOONGARCH_LAM; + } + if (config & CPUCFG2_FP) { + c->options |= LOONGARCH_CPU_FPU; + elf_hwcap |= HWCAP_LOONGARCH_FPU; + } + if (config & CPUCFG2_COMPLEX) { + c->options |= LOONGARCH_CPU_COMPLEX; + elf_hwcap |= HWCAP_LOONGARCH_COMPLEX; + } + if (config & CPUCFG2_CRYPTO) { + c->options |= LOONGARCH_CPU_CRYPTO; + elf_hwcap |= HWCAP_LOONGARCH_CRYPTO; + } + if (config & CPUCFG2_LVZP) { + c->options |= LOONGARCH_CPU_LVZ; + elf_hwcap |= HWCAP_LOONGARCH_LVZ; + } + + config = read_cpucfg(LOONGARCH_CPUCFG6); + if (config & CPUCFG6_PMP) + c->options |= LOONGARCH_CPU_PMP; + + config = iocsr_read32(LOONGARCH_IOCSR_FEATURES); + if (config & IOCSRF_CSRIPI) + c->options |= LOONGARCH_CPU_CSRIPI; + if (config & IOCSRF_EXTIOI) + c->options |= LOONGARCH_CPU_EXTIOI; + if (config & IOCSRF_FREQSCALE) + c->options |= LOONGARCH_CPU_SCALEFREQ; + if (config & IOCSRF_FLATMODE) + c->options |= LOONGARCH_CPU_FLATMODE; + if (config & IOCSRF_EIODECODE) + c->options |= LOONGARCH_CPU_EIODECODE; + if (config & IOCSRF_VM) + c->options |= LOONGARCH_CPU_HYPERVISOR; + + config = csr_read32(LOONGARCH_CSR_ASID); + config = (config & CSR_ASID_BIT) >> CSR_ASID_BIT_SHIFT; + asid_mask = GENMASK(config - 1, 0); + set_cpu_asid_mask(c, asid_mask); + + config = read_csr_prcfg1(); + c->ksave_mask = GENMASK((config & CSR_CONF1_KSNUM) - 1, 0); + c->ksave_mask &= ~(EXC_KSAVE_MASK | PERCPU_KSAVE_MASK | KVM_KSAVE_MASK); + + config = read_csr_prcfg3(); + switch (config & CSR_CONF3_TLBTYPE) { + case 0: + c->tlbsizemtlb = 0; + c->tlbsizestlbsets = 0; + c->tlbsizestlbways = 0; + c->tlbsize = 0; + break; + case 1: + c->tlbsizemtlb = ((config & CSR_CONF3_MTLBSIZE) >> CSR_CONF3_MTLBSIZE_SHIFT) + 1; + c->tlbsizestlbsets = 0; + c->tlbsizestlbways = 0; + c->tlbsize = c->tlbsizemtlb + c->tlbsizestlbsets * c->tlbsizestlbways; + break; + case 2: + c->tlbsizemtlb = ((config & CSR_CONF3_MTLBSIZE) >> CSR_CONF3_MTLBSIZE_SHIFT) + 1; + c->tlbsizestlbsets = 1 << ((config & CSR_CONF3_STLBIDX) >> CSR_CONF3_STLBIDX_SHIFT); + c->tlbsizestlbways = ((config & CSR_CONF3_STLBWAYS) >> CSR_CONF3_STLBWAYS_SHIFT) + 1; + c->tlbsize = c->tlbsizemtlb + c->tlbsizestlbsets * c->tlbsizestlbways; + break; + default: + pr_warn("Warning: unknown TLB type\n"); + } +} + +#define MAX_NAME_LEN 32 +#define VENDOR_OFFSET 0 +#define CPUNAME_OFFSET 9 + +static char cpu_full_name[MAX_NAME_LEN] = " - "; + +static inline void cpu_probe_loongson(struct cpuinfo_loongarch *c, unsigned int cpu) +{ + uint64_t *vendor = (void *)(&cpu_full_name[VENDOR_OFFSET]); + uint64_t *cpuname = (void *)(&cpu_full_name[CPUNAME_OFFSET]); + + if (!__cpu_full_name[cpu]) + __cpu_full_name[cpu] = cpu_full_name; + + *vendor = iocsr_read64(LOONGARCH_IOCSR_VENDOR); + *cpuname = iocsr_read64(LOONGARCH_IOCSR_CPUNAME); + + switch (c->processor_id & PRID_SERIES_MASK) { + case PRID_SERIES_LA132: + c->cputype = CPU_LOONGSON32; + set_isa(c, LOONGARCH_CPU_ISA_LA32S); + __cpu_family[cpu] = "Loongson-32bit"; + pr_info("32-bit Loongson Processor probed (LA132 Core)\n"); + break; + case PRID_SERIES_LA264: + c->cputype = CPU_LOONGSON64; + set_isa(c, LOONGARCH_CPU_ISA_LA64); + __cpu_family[cpu] = "Loongson-64bit"; + pr_info("64-bit Loongson Processor probed (LA264 Core)\n"); + break; + case PRID_SERIES_LA364: + c->cputype = CPU_LOONGSON64; + set_isa(c, LOONGARCH_CPU_ISA_LA64); + __cpu_family[cpu] = "Loongson-64bit"; + pr_info("64-bit Loongson Processor probed (LA364 Core)\n"); + break; + case PRID_SERIES_LA464: + c->cputype = CPU_LOONGSON64; + set_isa(c, LOONGARCH_CPU_ISA_LA64); + __cpu_family[cpu] = "Loongson-64bit"; + pr_info("64-bit Loongson Processor probed (LA464 Core)\n"); + break; + case PRID_SERIES_LA664: + c->cputype = CPU_LOONGSON64; + set_isa(c, LOONGARCH_CPU_ISA_LA64); + __cpu_family[cpu] = "Loongson-64bit"; + pr_info("64-bit Loongson Processor probed (LA664 Core)\n"); + break; + default: /* Default to 64 bit */ + c->cputype = CPU_LOONGSON64; + set_isa(c, LOONGARCH_CPU_ISA_LA64); + __cpu_family[cpu] = "Loongson-64bit"; + pr_info("64-bit Loongson Processor probed (Unknown Core)\n"); + } +} + +#ifdef CONFIG_64BIT +/* For use by uaccess.h */ +u64 __ua_limit; +EXPORT_SYMBOL(__ua_limit); +#endif + +const char *__cpu_family[NR_CPUS]; +const char *__cpu_full_name[NR_CPUS]; +const char *__elf_platform; + +static void cpu_report(void) +{ + struct cpuinfo_loongarch *c = ¤t_cpu_data; + + pr_info("CPU%d revision is: %08x (%s)\n", + smp_processor_id(), c->processor_id, cpu_family_string()); + if (c->options & LOONGARCH_CPU_FPU) + pr_info("FPU%d revision is: %08x\n", smp_processor_id(), c->fpu_vers); +} + +void cpu_probe(void) +{ + unsigned int cpu = smp_processor_id(); + struct cpuinfo_loongarch *c = ¤t_cpu_data; + + /* + * Set a default ELF platform, cpu probe may later + * overwrite it with a more precise value + */ + set_elf_platform(cpu, "loongarch"); + + c->cputype = CPU_UNKNOWN; + c->processor_id = read_cpucfg(LOONGARCH_CPUCFG0); + c->fpu_vers = (read_cpucfg(LOONGARCH_CPUCFG2) & CPUCFG2_FPVERS) >> 3; + + c->fpu_csr0 = FPU_CSR_RN; + c->fpu_mask = FPU_CSR_RSVD; + + cpu_probe_common(c); + + per_cpu_trap_init(cpu); + + switch (c->processor_id & PRID_COMP_MASK) { + case PRID_COMP_LOONGSON: + cpu_probe_loongson(c, cpu); + break; + } + + BUG_ON(!__cpu_family[cpu]); + BUG_ON(c->cputype == CPU_UNKNOWN); + + cpu_probe_addrbits(c); + +#ifdef CONFIG_64BIT + if (cpu == 0) + __ua_limit = ~((1ull << cpu_vabits) - 1); +#endif + + cpu_report(); +} |