linuxdebug/arch/loongarch/kernel/cpu-probe.c

300 lines
7.8 KiB
C

// 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(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_CPUCFG;
config = read_cpucfg(LOONGARCH_CPUCFG1);
if (config & CPUCFG1_UAL) {
c->options |= LOONGARCH_CPU_UAL;
elf_hwcap |= HWCAP_LOONGARCH_UAL;
}
if (config & CPUCFG1_CRC32) {
c->options |= LOONGARCH_CPU_CRC32;
elf_hwcap |= HWCAP_LOONGARCH_CRC32;
}
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 = &current_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 = &current_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();
}