WSL2-Linux-Kernel/arch/mips/kernel/cpu-probe.c

2105 строки
52 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Processor capabilities determination functions.
*
* Copyright (C) xxxx the Anonymous
* Copyright (C) 1994 - 2006 Ralf Baechle
* Copyright (C) 2003, 2004 Maciej W. Rozycki
* Copyright (C) 2001, 2004, 2011, 2012 MIPS Technologies, Inc.
*/
#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 <asm/bugs.h>
#include <asm/cpu.h>
#include <asm/cpu-features.h>
#include <asm/cpu-type.h>
#include <asm/fpu.h>
#include <asm/mipsregs.h>
#include <asm/mipsmtregs.h>
#include <asm/msa.h>
#include <asm/watch.h>
#include <asm/elf.h>
#include <asm/pgtable-bits.h>
#include <asm/spram.h>
#include <asm/traps.h>
#include <linux/uaccess.h>
#include "fpu-probe.h"
#include <asm/mach-loongson64/cpucfg-emul.h>
/* Hardware capabilities */
unsigned int elf_hwcap __read_mostly;
EXPORT_SYMBOL_GPL(elf_hwcap);
static inline unsigned long cpu_get_msa_id(void)
{
unsigned long status, msa_id;
status = read_c0_status();
__enable_fpu(FPU_64BIT);
enable_msa();
msa_id = read_msa_ir();
disable_msa();
write_c0_status(status);
return msa_id;
}
static int mips_dsp_disabled;
static int __init dsp_disable(char *s)
{
cpu_data[0].ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
mips_dsp_disabled = 1;
return 1;
}
__setup("nodsp", dsp_disable);
static int mips_htw_disabled;
static int __init htw_disable(char *s)
{
mips_htw_disabled = 1;
cpu_data[0].options &= ~MIPS_CPU_HTW;
write_c0_pwctl(read_c0_pwctl() &
~(1 << MIPS_PWCTL_PWEN_SHIFT));
return 1;
}
__setup("nohtw", htw_disable);
static int mips_ftlb_disabled;
static int mips_has_ftlb_configured;
enum ftlb_flags {
FTLB_EN = 1 << 0,
FTLB_SET_PROB = 1 << 1,
};
static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags);
static int __init ftlb_disable(char *s)
{
unsigned int config4, mmuextdef;
/*
* If the core hasn't done any FTLB configuration, there is nothing
* for us to do here.
*/
if (!mips_has_ftlb_configured)
return 1;
/* Disable it in the boot cpu */
if (set_ftlb_enable(&cpu_data[0], 0)) {
pr_warn("Can't turn FTLB off\n");
return 1;
}
config4 = read_c0_config4();
/* Check that FTLB has been disabled */
mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
/* MMUSIZEEXT == VTLB ON, FTLB OFF */
if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
/* This should never happen */
pr_warn("FTLB could not be disabled!\n");
return 1;
}
mips_ftlb_disabled = 1;
mips_has_ftlb_configured = 0;
/*
* noftlb is mainly used for debug purposes so print
* an informative message instead of using pr_debug()
*/
pr_info("FTLB has been disabled\n");
/*
* Some of these bits are duplicated in the decode_config4.
* MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
* once FTLB has been disabled so undo what decode_config4 did.
*/
cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
cpu_data[0].tlbsizeftlbsets;
cpu_data[0].tlbsizeftlbsets = 0;
cpu_data[0].tlbsizeftlbways = 0;
return 1;
}
__setup("noftlb", ftlb_disable);
/*
* Check if the CPU has per tc perf counters
*/
static inline void cpu_set_mt_per_tc_perf(struct cpuinfo_mips *c)
{
if (read_c0_config7() & MTI_CONF7_PTC)
c->options |= MIPS_CPU_MT_PER_TC_PERF_COUNTERS;
}
static inline void check_errata(void)
{
struct cpuinfo_mips *c = &current_cpu_data;
switch (current_cpu_type()) {
case CPU_34K:
/*
* Erratum "RPS May Cause Incorrect Instruction Execution"
* This code only handles VPE0, any SMP/RTOS code
* making use of VPE1 will be responsable for that VPE.
*/
if ((c->processor_id & PRID_REV_MASK) <= PRID_REV_34K_V1_0_2)
write_c0_config7(read_c0_config7() | MIPS_CONF7_RPS);
break;
default:
break;
}
}
void __init check_bugs32(void)
{
check_errata();
}
/*
* Probe whether cpu has config register by trying to play with
* alternate cache bit and see whether it matters.
* It's used by cpu_probe to distinguish between R3000A and R3081.
*/
static inline int cpu_has_confreg(void)
{
#ifdef CONFIG_CPU_R3000
extern unsigned long r3k_cache_size(unsigned long);
unsigned long size1, size2;
unsigned long cfg = read_c0_conf();
size1 = r3k_cache_size(ST0_ISC);
write_c0_conf(cfg ^ R30XX_CONF_AC);
size2 = r3k_cache_size(ST0_ISC);
write_c0_conf(cfg);
return size1 != size2;
#else
return 0;
#endif
}
static inline void set_elf_platform(int cpu, const char *plat)
{
if (cpu == 0)
__elf_platform = plat;
}
static inline void set_elf_base_platform(const char *plat)
{
if (__elf_base_platform == NULL) {
__elf_base_platform = plat;
}
}
static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
{
#ifdef __NEED_VMBITS_PROBE
write_c0_entryhi(0x3fffffffffffe000ULL);
back_to_back_c0_hazard();
c->vmbits = fls64(read_c0_entryhi() & 0x3fffffffffffe000ULL);
#endif
}
static void set_isa(struct cpuinfo_mips *c, unsigned int isa)
{
switch (isa) {
case MIPS_CPU_ISA_M64R5:
c->isa_level |= MIPS_CPU_ISA_M32R5 | MIPS_CPU_ISA_M64R5;
set_elf_base_platform("mips64r5");
fallthrough;
case MIPS_CPU_ISA_M64R2:
c->isa_level |= MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M64R2;
set_elf_base_platform("mips64r2");
fallthrough;
case MIPS_CPU_ISA_M64R1:
c->isa_level |= MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M64R1;
set_elf_base_platform("mips64");
fallthrough;
case MIPS_CPU_ISA_V:
c->isa_level |= MIPS_CPU_ISA_V;
set_elf_base_platform("mips5");
fallthrough;
case MIPS_CPU_ISA_IV:
c->isa_level |= MIPS_CPU_ISA_IV;
set_elf_base_platform("mips4");
fallthrough;
case MIPS_CPU_ISA_III:
c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
set_elf_base_platform("mips3");
break;
/* R6 incompatible with everything else */
case MIPS_CPU_ISA_M64R6:
c->isa_level |= MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R6;
set_elf_base_platform("mips64r6");
fallthrough;
case MIPS_CPU_ISA_M32R6:
c->isa_level |= MIPS_CPU_ISA_M32R6;
set_elf_base_platform("mips32r6");
/* Break here so we don't add incompatible ISAs */
break;
case MIPS_CPU_ISA_M32R5:
c->isa_level |= MIPS_CPU_ISA_M32R5;
set_elf_base_platform("mips32r5");
fallthrough;
case MIPS_CPU_ISA_M32R2:
c->isa_level |= MIPS_CPU_ISA_M32R2;
set_elf_base_platform("mips32r2");
fallthrough;
case MIPS_CPU_ISA_M32R1:
c->isa_level |= MIPS_CPU_ISA_M32R1;
set_elf_base_platform("mips32");
fallthrough;
case MIPS_CPU_ISA_II:
c->isa_level |= MIPS_CPU_ISA_II;
set_elf_base_platform("mips2");
break;
}
}
static char unknown_isa[] = KERN_ERR \
"Unsupported ISA type, c0.config0: %d.";
static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
{
unsigned int probability = c->tlbsize / c->tlbsizevtlb;
/*
* 0 = All TLBWR instructions go to FTLB
* 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
* FTLB and 1 goes to the VTLB.
* 2 = 7:1: As above with 7:1 ratio.
* 3 = 3:1: As above with 3:1 ratio.
*
* Use the linear midpoint as the probability threshold.
*/
if (probability >= 12)
return 1;
else if (probability >= 6)
return 2;
else
/*
* So FTLB is less than 4 times bigger than VTLB.
* A 3:1 ratio can still be useful though.
*/
return 3;
}
static int set_ftlb_enable(struct cpuinfo_mips *c, enum ftlb_flags flags)
{
unsigned int config;
/* It's implementation dependent how the FTLB can be enabled */
switch (c->cputype) {
case CPU_PROAPTIV:
case CPU_P5600:
case CPU_P6600:
/* proAptiv & related cores use Config6 to enable the FTLB */
config = read_c0_config6();
if (flags & FTLB_EN)
config |= MTI_CONF6_FTLBEN;
else
config &= ~MTI_CONF6_FTLBEN;
if (flags & FTLB_SET_PROB) {
config &= ~(3 << MTI_CONF6_FTLBP_SHIFT);
config |= calculate_ftlb_probability(c)
<< MTI_CONF6_FTLBP_SHIFT;
}
write_c0_config6(config);
back_to_back_c0_hazard();
break;
case CPU_I6400:
case CPU_I6500:
/* There's no way to disable the FTLB */
if (!(flags & FTLB_EN))
return 1;
return 0;
case CPU_LOONGSON64:
/* Flush ITLB, DTLB, VTLB and FTLB */
write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |
LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);
/* Loongson-3 cores use Config6 to enable the FTLB */
config = read_c0_config6();
if (flags & FTLB_EN)
/* Enable FTLB */
write_c0_config6(config & ~LOONGSON_CONF6_FTLBDIS);
else
/* Disable FTLB */
write_c0_config6(config | LOONGSON_CONF6_FTLBDIS);
break;
default:
return 1;
}
return 0;
}
static int mm_config(struct cpuinfo_mips *c)
{
unsigned int config0, update, mm;
config0 = read_c0_config();
mm = config0 & MIPS_CONF_MM;
/*
* It's implementation dependent what type of write-merge is supported
* and whether it can be enabled/disabled. If it is settable lets make
* the merging allowed by default. Some platforms might have
* write-through caching unsupported. In this case just ignore the
* CP0.Config.MM bit field value.
*/
switch (c->cputype) {
case CPU_24K:
case CPU_34K:
case CPU_74K:
case CPU_P5600:
case CPU_P6600:
c->options |= MIPS_CPU_MM_FULL;
update = MIPS_CONF_MM_FULL;
break;
case CPU_1004K:
case CPU_1074K:
case CPU_INTERAPTIV:
case CPU_PROAPTIV:
mm = 0;
fallthrough;
default:
update = 0;
break;
}
if (update) {
config0 = (config0 & ~MIPS_CONF_MM) | update;
write_c0_config(config0);
} else if (mm == MIPS_CONF_MM_SYSAD) {
c->options |= MIPS_CPU_MM_SYSAD;
} else if (mm == MIPS_CONF_MM_FULL) {
c->options |= MIPS_CPU_MM_FULL;
}
return 0;
}
static inline unsigned int decode_config0(struct cpuinfo_mips *c)
{
unsigned int config0;
int isa, mt;
config0 = read_c0_config();
/*
* Look for Standard TLB or Dual VTLB and FTLB
*/
mt = config0 & MIPS_CONF_MT;
if (mt == MIPS_CONF_MT_TLB)
c->options |= MIPS_CPU_TLB;
else if (mt == MIPS_CONF_MT_FTLB)
c->options |= MIPS_CPU_TLB | MIPS_CPU_FTLB;
isa = (config0 & MIPS_CONF_AT) >> 13;
switch (isa) {
case 0:
switch ((config0 & MIPS_CONF_AR) >> 10) {
case 0:
set_isa(c, MIPS_CPU_ISA_M32R1);
break;
case 1:
set_isa(c, MIPS_CPU_ISA_M32R2);
break;
case 2:
set_isa(c, MIPS_CPU_ISA_M32R6);
break;
default:
goto unknown;
}
break;
case 2:
switch ((config0 & MIPS_CONF_AR) >> 10) {
case 0:
set_isa(c, MIPS_CPU_ISA_M64R1);
break;
case 1:
set_isa(c, MIPS_CPU_ISA_M64R2);
break;
case 2:
set_isa(c, MIPS_CPU_ISA_M64R6);
break;
default:
goto unknown;
}
break;
default:
goto unknown;
}
return config0 & MIPS_CONF_M;
unknown:
panic(unknown_isa, config0);
}
static inline unsigned int decode_config1(struct cpuinfo_mips *c)
{
unsigned int config1;
config1 = read_c0_config1();
if (config1 & MIPS_CONF1_MD)
c->ases |= MIPS_ASE_MDMX;
if (config1 & MIPS_CONF1_PC)
c->options |= MIPS_CPU_PERF;
if (config1 & MIPS_CONF1_WR)
c->options |= MIPS_CPU_WATCH;
if (config1 & MIPS_CONF1_CA)
c->ases |= MIPS_ASE_MIPS16;
if (config1 & MIPS_CONF1_EP)
c->options |= MIPS_CPU_EJTAG;
if (config1 & MIPS_CONF1_FP) {
c->options |= MIPS_CPU_FPU;
c->options |= MIPS_CPU_32FPR;
}
if (cpu_has_tlb) {
c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
c->tlbsizevtlb = c->tlbsize;
c->tlbsizeftlbsets = 0;
}
return config1 & MIPS_CONF_M;
}
static inline unsigned int decode_config2(struct cpuinfo_mips *c)
{
unsigned int config2;
config2 = read_c0_config2();
if (config2 & MIPS_CONF2_SL)
c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
return config2 & MIPS_CONF_M;
}
static inline unsigned int decode_config3(struct cpuinfo_mips *c)
{
unsigned int config3;
config3 = read_c0_config3();
if (config3 & MIPS_CONF3_SM) {
c->ases |= MIPS_ASE_SMARTMIPS;
c->options |= MIPS_CPU_RIXI | MIPS_CPU_CTXTC;
}
if (config3 & MIPS_CONF3_RXI)
c->options |= MIPS_CPU_RIXI;
if (config3 & MIPS_CONF3_CTXTC)
c->options |= MIPS_CPU_CTXTC;
if (config3 & MIPS_CONF3_DSP)
c->ases |= MIPS_ASE_DSP;
if (config3 & MIPS_CONF3_DSP2P) {
c->ases |= MIPS_ASE_DSP2P;
if (cpu_has_mips_r6)
c->ases |= MIPS_ASE_DSP3;
}
if (config3 & MIPS_CONF3_VINT)
c->options |= MIPS_CPU_VINT;
if (config3 & MIPS_CONF3_VEIC)
c->options |= MIPS_CPU_VEIC;
if (config3 & MIPS_CONF3_LPA)
c->options |= MIPS_CPU_LPA;
if (config3 & MIPS_CONF3_MT)
c->ases |= MIPS_ASE_MIPSMT;
if (config3 & MIPS_CONF3_ULRI)
c->options |= MIPS_CPU_ULRI;
if (config3 & MIPS_CONF3_ISA)
c->options |= MIPS_CPU_MICROMIPS;
if (config3 & MIPS_CONF3_VZ)
c->ases |= MIPS_ASE_VZ;
if (config3 & MIPS_CONF3_SC)
c->options |= MIPS_CPU_SEGMENTS;
if (config3 & MIPS_CONF3_BI)
c->options |= MIPS_CPU_BADINSTR;
if (config3 & MIPS_CONF3_BP)
c->options |= MIPS_CPU_BADINSTRP;
if (config3 & MIPS_CONF3_MSA)
c->ases |= MIPS_ASE_MSA;
if (config3 & MIPS_CONF3_PW) {
c->htw_seq = 0;
c->options |= MIPS_CPU_HTW;
}
if (config3 & MIPS_CONF3_CDMM)
c->options |= MIPS_CPU_CDMM;
if (config3 & MIPS_CONF3_SP)
c->options |= MIPS_CPU_SP;
return config3 & MIPS_CONF_M;
}
static inline unsigned int decode_config4(struct cpuinfo_mips *c)
{
unsigned int config4;
unsigned int newcf4;
unsigned int mmuextdef;
unsigned int ftlb_page = MIPS_CONF4_FTLBPAGESIZE;
unsigned long asid_mask;
config4 = read_c0_config4();
if (cpu_has_tlb) {
if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
c->options |= MIPS_CPU_TLBINV;
/*
* R6 has dropped the MMUExtDef field from config4.
* On R6 the fields always describe the FTLB, and only if it is
* present according to Config.MT.
*/
if (!cpu_has_mips_r6)
mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
else if (cpu_has_ftlb)
mmuextdef = MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT;
else
mmuextdef = 0;
switch (mmuextdef) {
case MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT:
c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
c->tlbsizevtlb = c->tlbsize;
break;
case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
c->tlbsizevtlb +=
((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
MIPS_CONF4_VTLBSIZEEXT_SHIFT) * 0x40;
c->tlbsize = c->tlbsizevtlb;
ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
fallthrough;
case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
if (mips_ftlb_disabled)
break;
newcf4 = (config4 & ~ftlb_page) |
(page_size_ftlb(mmuextdef) <<
MIPS_CONF4_FTLBPAGESIZE_SHIFT);
write_c0_config4(newcf4);
back_to_back_c0_hazard();
config4 = read_c0_config4();
if (config4 != newcf4) {
pr_err("PAGE_SIZE 0x%lx is not supported by FTLB (config4=0x%x)\n",
PAGE_SIZE, config4);
/* Switch FTLB off */
set_ftlb_enable(c, 0);
mips_ftlb_disabled = 1;
break;
}
c->tlbsizeftlbsets = 1 <<
((config4 & MIPS_CONF4_FTLBSETS) >>
MIPS_CONF4_FTLBSETS_SHIFT);
c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
mips_has_ftlb_configured = 1;
break;
}
}
c->kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
>> MIPS_CONF4_KSCREXIST_SHIFT;
asid_mask = MIPS_ENTRYHI_ASID;
if (config4 & MIPS_CONF4_AE)
asid_mask |= MIPS_ENTRYHI_ASIDX;
set_cpu_asid_mask(c, asid_mask);
/*
* Warn if the computed ASID mask doesn't match the mask the kernel
* is built for. This may indicate either a serious problem or an
* easy optimisation opportunity, but either way should be addressed.
*/
WARN_ON(asid_mask != cpu_asid_mask(c));
return config4 & MIPS_CONF_M;
}
static inline unsigned int decode_config5(struct cpuinfo_mips *c)
{
unsigned int config5, max_mmid_width;
unsigned long asid_mask;
config5 = read_c0_config5();
config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
if (cpu_has_mips_r6) {
if (!__builtin_constant_p(cpu_has_mmid) || cpu_has_mmid)
config5 |= MIPS_CONF5_MI;
else
config5 &= ~MIPS_CONF5_MI;
}
write_c0_config5(config5);
if (config5 & MIPS_CONF5_EVA)
c->options |= MIPS_CPU_EVA;
if (config5 & MIPS_CONF5_MRP)
c->options |= MIPS_CPU_MAAR;
if (config5 & MIPS_CONF5_LLB)
c->options |= MIPS_CPU_RW_LLB;
if (config5 & MIPS_CONF5_MVH)
c->options |= MIPS_CPU_MVH;
if (cpu_has_mips_r6 && (config5 & MIPS_CONF5_VP))
c->options |= MIPS_CPU_VP;
if (config5 & MIPS_CONF5_CA2)
c->ases |= MIPS_ASE_MIPS16E2;
if (config5 & MIPS_CONF5_CRCP)
elf_hwcap |= HWCAP_MIPS_CRC32;
if (cpu_has_mips_r6) {
/* Ensure the write to config5 above takes effect */
back_to_back_c0_hazard();
/* Check whether we successfully enabled MMID support */
config5 = read_c0_config5();
if (config5 & MIPS_CONF5_MI)
c->options |= MIPS_CPU_MMID;
/*
* Warn if we've hardcoded cpu_has_mmid to a value unsuitable
* for the CPU we're running on, or if CPUs in an SMP system
* have inconsistent MMID support.
*/
WARN_ON(!!cpu_has_mmid != !!(config5 & MIPS_CONF5_MI));
if (cpu_has_mmid) {
write_c0_memorymapid(~0ul);
back_to_back_c0_hazard();
asid_mask = read_c0_memorymapid();
/*
* We maintain a bitmap to track MMID allocation, and
* need a sensible upper bound on the size of that
* bitmap. The initial CPU with MMID support (I6500)
* supports 16 bit MMIDs, which gives us an 8KiB
* bitmap. The architecture recommends that hardware
* support 32 bit MMIDs, which would give us a 512MiB
* bitmap - that's too big in most cases.
*
* Cap MMID width at 16 bits for now & we can revisit
* this if & when hardware supports anything wider.
*/
max_mmid_width = 16;
if (asid_mask > GENMASK(max_mmid_width - 1, 0)) {
pr_info("Capping MMID width at %d bits",
max_mmid_width);
asid_mask = GENMASK(max_mmid_width - 1, 0);
}
set_cpu_asid_mask(c, asid_mask);
}
}
return config5 & MIPS_CONF_M;
}
static void decode_configs(struct cpuinfo_mips *c)
{
int ok;
/* MIPS32 or MIPS64 compliant CPU. */
c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
c->scache.flags = MIPS_CACHE_NOT_PRESENT;
/* Enable FTLB if present and not disabled */
set_ftlb_enable(c, mips_ftlb_disabled ? 0 : FTLB_EN);
ok = decode_config0(c); /* Read Config registers. */
BUG_ON(!ok); /* Arch spec violation! */
if (ok)
ok = decode_config1(c);
if (ok)
ok = decode_config2(c);
if (ok)
ok = decode_config3(c);
if (ok)
ok = decode_config4(c);
if (ok)
ok = decode_config5(c);
/* Probe the EBase.WG bit */
if (cpu_has_mips_r2_r6) {
u64 ebase;
unsigned int status;
/* {read,write}_c0_ebase_64() may be UNDEFINED prior to r6 */
ebase = cpu_has_mips64r6 ? read_c0_ebase_64()
: (s32)read_c0_ebase();
if (ebase & MIPS_EBASE_WG) {
/* WG bit already set, we can avoid the clumsy probe */
c->options |= MIPS_CPU_EBASE_WG;
} else {
/* Its UNDEFINED to change EBase while BEV=0 */
status = read_c0_status();
write_c0_status(status | ST0_BEV);
irq_enable_hazard();
/*
* On pre-r6 cores, this may well clobber the upper bits
* of EBase. This is hard to avoid without potentially
* hitting UNDEFINED dm*c0 behaviour if EBase is 32-bit.
*/
if (cpu_has_mips64r6)
write_c0_ebase_64(ebase | MIPS_EBASE_WG);
else
write_c0_ebase(ebase | MIPS_EBASE_WG);
back_to_back_c0_hazard();
/* Restore BEV */
write_c0_status(status);
if (read_c0_ebase() & MIPS_EBASE_WG) {
c->options |= MIPS_CPU_EBASE_WG;
write_c0_ebase(ebase);
}
}
}
/* configure the FTLB write probability */
set_ftlb_enable(c, (mips_ftlb_disabled ? 0 : FTLB_EN) | FTLB_SET_PROB);
mips_probe_watch_registers(c);
#ifndef CONFIG_MIPS_CPS
if (cpu_has_mips_r2_r6) {
unsigned int core;
core = get_ebase_cpunum();
if (cpu_has_mipsmt)
core >>= fls(core_nvpes()) - 1;
cpu_set_core(c, core);
}
#endif
}
/*
* Probe for certain guest capabilities by writing config bits and reading back.
* Finally write back the original value.
*/
#define probe_gc0_config(name, maxconf, bits) \
do { \
unsigned int tmp; \
tmp = read_gc0_##name(); \
write_gc0_##name(tmp | (bits)); \
back_to_back_c0_hazard(); \
maxconf = read_gc0_##name(); \
write_gc0_##name(tmp); \
} while (0)
/*
* Probe for dynamic guest capabilities by changing certain config bits and
* reading back to see if they change. Finally write back the original value.
*/
#define probe_gc0_config_dyn(name, maxconf, dynconf, bits) \
do { \
maxconf = read_gc0_##name(); \
write_gc0_##name(maxconf ^ (bits)); \
back_to_back_c0_hazard(); \
dynconf = maxconf ^ read_gc0_##name(); \
write_gc0_##name(maxconf); \
maxconf |= dynconf; \
} while (0)
static inline unsigned int decode_guest_config0(struct cpuinfo_mips *c)
{
unsigned int config0;
probe_gc0_config(config, config0, MIPS_CONF_M);
if (config0 & MIPS_CONF_M)
c->guest.conf |= BIT(1);
return config0 & MIPS_CONF_M;
}
static inline unsigned int decode_guest_config1(struct cpuinfo_mips *c)
{
unsigned int config1, config1_dyn;
probe_gc0_config_dyn(config1, config1, config1_dyn,
MIPS_CONF_M | MIPS_CONF1_PC | MIPS_CONF1_WR |
MIPS_CONF1_FP);
if (config1 & MIPS_CONF1_FP)
c->guest.options |= MIPS_CPU_FPU;
if (config1_dyn & MIPS_CONF1_FP)
c->guest.options_dyn |= MIPS_CPU_FPU;
if (config1 & MIPS_CONF1_WR)
c->guest.options |= MIPS_CPU_WATCH;
if (config1_dyn & MIPS_CONF1_WR)
c->guest.options_dyn |= MIPS_CPU_WATCH;
if (config1 & MIPS_CONF1_PC)
c->guest.options |= MIPS_CPU_PERF;
if (config1_dyn & MIPS_CONF1_PC)
c->guest.options_dyn |= MIPS_CPU_PERF;
if (config1 & MIPS_CONF_M)
c->guest.conf |= BIT(2);
return config1 & MIPS_CONF_M;
}
static inline unsigned int decode_guest_config2(struct cpuinfo_mips *c)
{
unsigned int config2;
probe_gc0_config(config2, config2, MIPS_CONF_M);
if (config2 & MIPS_CONF_M)
c->guest.conf |= BIT(3);
return config2 & MIPS_CONF_M;
}
static inline unsigned int decode_guest_config3(struct cpuinfo_mips *c)
{
unsigned int config3, config3_dyn;
probe_gc0_config_dyn(config3, config3, config3_dyn,
MIPS_CONF_M | MIPS_CONF3_MSA | MIPS_CONF3_ULRI |
MIPS_CONF3_CTXTC);
if (config3 & MIPS_CONF3_CTXTC)
c->guest.options |= MIPS_CPU_CTXTC;
if (config3_dyn & MIPS_CONF3_CTXTC)
c->guest.options_dyn |= MIPS_CPU_CTXTC;
if (config3 & MIPS_CONF3_PW)
c->guest.options |= MIPS_CPU_HTW;
if (config3 & MIPS_CONF3_ULRI)
c->guest.options |= MIPS_CPU_ULRI;
if (config3 & MIPS_CONF3_SC)
c->guest.options |= MIPS_CPU_SEGMENTS;
if (config3 & MIPS_CONF3_BI)
c->guest.options |= MIPS_CPU_BADINSTR;
if (config3 & MIPS_CONF3_BP)
c->guest.options |= MIPS_CPU_BADINSTRP;
if (config3 & MIPS_CONF3_MSA)
c->guest.ases |= MIPS_ASE_MSA;
if (config3_dyn & MIPS_CONF3_MSA)
c->guest.ases_dyn |= MIPS_ASE_MSA;
if (config3 & MIPS_CONF_M)
c->guest.conf |= BIT(4);
return config3 & MIPS_CONF_M;
}
static inline unsigned int decode_guest_config4(struct cpuinfo_mips *c)
{
unsigned int config4;
probe_gc0_config(config4, config4,
MIPS_CONF_M | MIPS_CONF4_KSCREXIST);
c->guest.kscratch_mask = (config4 & MIPS_CONF4_KSCREXIST)
>> MIPS_CONF4_KSCREXIST_SHIFT;
if (config4 & MIPS_CONF_M)
c->guest.conf |= BIT(5);
return config4 & MIPS_CONF_M;
}
static inline unsigned int decode_guest_config5(struct cpuinfo_mips *c)
{
unsigned int config5, config5_dyn;
probe_gc0_config_dyn(config5, config5, config5_dyn,
MIPS_CONF_M | MIPS_CONF5_MVH | MIPS_CONF5_MRP);
if (config5 & MIPS_CONF5_MRP)
c->guest.options |= MIPS_CPU_MAAR;
if (config5_dyn & MIPS_CONF5_MRP)
c->guest.options_dyn |= MIPS_CPU_MAAR;
if (config5 & MIPS_CONF5_LLB)
c->guest.options |= MIPS_CPU_RW_LLB;
if (config5 & MIPS_CONF5_MVH)
c->guest.options |= MIPS_CPU_MVH;
if (config5 & MIPS_CONF_M)
c->guest.conf |= BIT(6);
return config5 & MIPS_CONF_M;
}
static inline void decode_guest_configs(struct cpuinfo_mips *c)
{
unsigned int ok;
ok = decode_guest_config0(c);
if (ok)
ok = decode_guest_config1(c);
if (ok)
ok = decode_guest_config2(c);
if (ok)
ok = decode_guest_config3(c);
if (ok)
ok = decode_guest_config4(c);
if (ok)
decode_guest_config5(c);
}
static inline void cpu_probe_guestctl0(struct cpuinfo_mips *c)
{
unsigned int guestctl0, temp;
guestctl0 = read_c0_guestctl0();
if (guestctl0 & MIPS_GCTL0_G0E)
c->options |= MIPS_CPU_GUESTCTL0EXT;
if (guestctl0 & MIPS_GCTL0_G1)
c->options |= MIPS_CPU_GUESTCTL1;
if (guestctl0 & MIPS_GCTL0_G2)
c->options |= MIPS_CPU_GUESTCTL2;
if (!(guestctl0 & MIPS_GCTL0_RAD)) {
c->options |= MIPS_CPU_GUESTID;
/*
* Probe for Direct Root to Guest (DRG). Set GuestCtl1.RID = 0
* first, otherwise all data accesses will be fully virtualised
* as if they were performed by guest mode.
*/
write_c0_guestctl1(0);
tlbw_use_hazard();
write_c0_guestctl0(guestctl0 | MIPS_GCTL0_DRG);
back_to_back_c0_hazard();
temp = read_c0_guestctl0();
if (temp & MIPS_GCTL0_DRG) {
write_c0_guestctl0(guestctl0);
c->options |= MIPS_CPU_DRG;
}
}
}
static inline void cpu_probe_guestctl1(struct cpuinfo_mips *c)
{
if (cpu_has_guestid) {
/* determine the number of bits of GuestID available */
write_c0_guestctl1(MIPS_GCTL1_ID);
back_to_back_c0_hazard();
c->guestid_mask = (read_c0_guestctl1() & MIPS_GCTL1_ID)
>> MIPS_GCTL1_ID_SHIFT;
write_c0_guestctl1(0);
}
}
static inline void cpu_probe_gtoffset(struct cpuinfo_mips *c)
{
/* determine the number of bits of GTOffset available */
write_c0_gtoffset(0xffffffff);
back_to_back_c0_hazard();
c->gtoffset_mask = read_c0_gtoffset();
write_c0_gtoffset(0);
}
static inline void cpu_probe_vz(struct cpuinfo_mips *c)
{
cpu_probe_guestctl0(c);
if (cpu_has_guestctl1)
cpu_probe_guestctl1(c);
cpu_probe_gtoffset(c);
decode_guest_configs(c);
}
#define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
| MIPS_CPU_COUNTER)
static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
{
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_R2000:
c->cputype = CPU_R2000;
__cpu_name[cpu] = "R2000";
c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
MIPS_CPU_NOFPUEX;
if (__cpu_has_fpu())
c->options |= MIPS_CPU_FPU;
c->tlbsize = 64;
break;
case PRID_IMP_R3000:
if ((c->processor_id & PRID_REV_MASK) == PRID_REV_R3000A) {
if (cpu_has_confreg()) {
c->cputype = CPU_R3081E;
__cpu_name[cpu] = "R3081";
} else {
c->cputype = CPU_R3000A;
__cpu_name[cpu] = "R3000A";
}
} else {
c->cputype = CPU_R3000;
__cpu_name[cpu] = "R3000";
}
c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
MIPS_CPU_NOFPUEX;
if (__cpu_has_fpu())
c->options |= MIPS_CPU_FPU;
c->tlbsize = 64;
break;
case PRID_IMP_R4000:
if (read_c0_config() & CONF_SC) {
if ((c->processor_id & PRID_REV_MASK) >=
PRID_REV_R4400) {
c->cputype = CPU_R4400PC;
__cpu_name[cpu] = "R4400PC";
} else {
c->cputype = CPU_R4000PC;
__cpu_name[cpu] = "R4000PC";
}
} else {
int cca = read_c0_config() & CONF_CM_CMASK;
int mc;
/*
* SC and MC versions can't be reliably told apart,
* but only the latter support coherent caching
* modes so assume the firmware has set the KSEG0
* coherency attribute reasonably (if uncached, we
* assume SC).
*/
switch (cca) {
case CONF_CM_CACHABLE_CE:
case CONF_CM_CACHABLE_COW:
case CONF_CM_CACHABLE_CUW:
mc = 1;
break;
default:
mc = 0;
break;
}
if ((c->processor_id & PRID_REV_MASK) >=
PRID_REV_R4400) {
c->cputype = mc ? CPU_R4400MC : CPU_R4400SC;
__cpu_name[cpu] = mc ? "R4400MC" : "R4400SC";
} else {
c->cputype = mc ? CPU_R4000MC : CPU_R4000SC;
__cpu_name[cpu] = mc ? "R4000MC" : "R4000SC";
}
}
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_WATCH | MIPS_CPU_VCE |
MIPS_CPU_LLSC;
c->tlbsize = 48;
break;
case PRID_IMP_VR41XX:
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
c->options = R4K_OPTS;
c->tlbsize = 32;
switch (c->processor_id & 0xf0) {
case PRID_REV_VR4111:
c->cputype = CPU_VR4111;
__cpu_name[cpu] = "NEC VR4111";
break;
case PRID_REV_VR4121:
c->cputype = CPU_VR4121;
__cpu_name[cpu] = "NEC VR4121";
break;
case PRID_REV_VR4122:
if ((c->processor_id & 0xf) < 0x3) {
c->cputype = CPU_VR4122;
__cpu_name[cpu] = "NEC VR4122";
} else {
c->cputype = CPU_VR4181A;
__cpu_name[cpu] = "NEC VR4181A";
}
break;
case PRID_REV_VR4130:
if ((c->processor_id & 0xf) < 0x4) {
c->cputype = CPU_VR4131;
__cpu_name[cpu] = "NEC VR4131";
} else {
c->cputype = CPU_VR4133;
c->options |= MIPS_CPU_LLSC;
__cpu_name[cpu] = "NEC VR4133";
}
break;
default:
printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
c->cputype = CPU_VR41XX;
__cpu_name[cpu] = "NEC Vr41xx";
break;
}
break;
case PRID_IMP_R4300:
c->cputype = CPU_R4300;
__cpu_name[cpu] = "R4300";
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_LLSC;
c->tlbsize = 32;
break;
case PRID_IMP_R4600:
c->cputype = CPU_R4600;
__cpu_name[cpu] = "R4600";
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_LLSC;
c->tlbsize = 48;
break;
#if 0
case PRID_IMP_R4650:
/*
* This processor doesn't have an MMU, so it's not
* "real easy" to run Linux on it. It is left purely
* for documentation. Commented out because it shares
* it's c0_prid id number with the TX3900.
*/
c->cputype = CPU_R4650;
__cpu_name[cpu] = "R4650";
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_LLSC;
c->tlbsize = 48;
break;
#endif
case PRID_IMP_TX39:
c->fpu_msk31 |= FPU_CSR_CONDX | FPU_CSR_FS;
c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
c->cputype = CPU_TX3927;
__cpu_name[cpu] = "TX3927";
c->tlbsize = 64;
} else {
switch (c->processor_id & PRID_REV_MASK) {
case PRID_REV_TX3912:
c->cputype = CPU_TX3912;
__cpu_name[cpu] = "TX3912";
c->tlbsize = 32;
break;
case PRID_REV_TX3922:
c->cputype = CPU_TX3922;
__cpu_name[cpu] = "TX3922";
c->tlbsize = 64;
break;
}
}
break;
case PRID_IMP_R4700:
c->cputype = CPU_R4700;
__cpu_name[cpu] = "R4700";
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_LLSC;
c->tlbsize = 48;
break;
case PRID_IMP_TX49:
c->cputype = CPU_TX49XX;
__cpu_name[cpu] = "R49XX";
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
c->options = R4K_OPTS | MIPS_CPU_LLSC;
if (!(c->processor_id & 0x08))
c->options |= MIPS_CPU_FPU | MIPS_CPU_32FPR;
c->tlbsize = 48;
break;
case PRID_IMP_R5000:
c->cputype = CPU_R5000;
__cpu_name[cpu] = "R5000";
set_isa(c, MIPS_CPU_ISA_IV);
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_LLSC;
c->tlbsize = 48;
break;
case PRID_IMP_R5500:
c->cputype = CPU_R5500;
__cpu_name[cpu] = "R5500";
set_isa(c, MIPS_CPU_ISA_IV);
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_WATCH | MIPS_CPU_LLSC;
c->tlbsize = 48;
break;
case PRID_IMP_NEVADA:
c->cputype = CPU_NEVADA;
__cpu_name[cpu] = "Nevada";
set_isa(c, MIPS_CPU_ISA_IV);
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_DIVEC | MIPS_CPU_LLSC;
c->tlbsize = 48;
break;
case PRID_IMP_RM7000:
c->cputype = CPU_RM7000;
__cpu_name[cpu] = "RM7000";
set_isa(c, MIPS_CPU_ISA_IV);
c->options = R4K_OPTS | MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_LLSC;
/*
* Undocumented RM7000: Bit 29 in the info register of
* the RM7000 v2.0 indicates if the TLB has 48 or 64
* entries.
*
* 29 1 => 64 entry JTLB
* 0 => 48 entry JTLB
*/
c->tlbsize = (read_c0_info() & (1 << 29)) ? 64 : 48;
break;
case PRID_IMP_R10000:
c->cputype = CPU_R10000;
__cpu_name[cpu] = "R10000";
set_isa(c, MIPS_CPU_ISA_IV);
c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
MIPS_CPU_LLSC;
c->tlbsize = 64;
break;
case PRID_IMP_R12000:
c->cputype = CPU_R12000;
__cpu_name[cpu] = "R12000";
set_isa(c, MIPS_CPU_ISA_IV);
c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
MIPS_CPU_LLSC;
c->tlbsize = 64;
write_c0_r10k_diag(read_c0_r10k_diag() | R10K_DIAG_E_GHIST);
break;
case PRID_IMP_R14000:
if (((c->processor_id >> 4) & 0x0f) > 2) {
c->cputype = CPU_R16000;
__cpu_name[cpu] = "R16000";
} else {
c->cputype = CPU_R14000;
__cpu_name[cpu] = "R14000";
}
set_isa(c, MIPS_CPU_ISA_IV);
c->options = MIPS_CPU_TLB | MIPS_CPU_4K_CACHE | MIPS_CPU_4KEX |
MIPS_CPU_FPU | MIPS_CPU_32FPR |
MIPS_CPU_COUNTER | MIPS_CPU_WATCH |
MIPS_CPU_LLSC;
c->tlbsize = 64;
write_c0_r10k_diag(read_c0_r10k_diag() | R10K_DIAG_E_GHIST);
break;
case PRID_IMP_LOONGSON_64C: /* Loongson-2/3 */
switch (c->processor_id & PRID_REV_MASK) {
case PRID_REV_LOONGSON2E:
c->cputype = CPU_LOONGSON2EF;
__cpu_name[cpu] = "ICT Loongson-2";
set_elf_platform(cpu, "loongson2e");
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
break;
case PRID_REV_LOONGSON2F:
c->cputype = CPU_LOONGSON2EF;
__cpu_name[cpu] = "ICT Loongson-2";
set_elf_platform(cpu, "loongson2f");
set_isa(c, MIPS_CPU_ISA_III);
c->fpu_msk31 |= FPU_CSR_CONDX;
break;
case PRID_REV_LOONGSON3A_R1:
c->cputype = CPU_LOONGSON64;
__cpu_name[cpu] = "ICT Loongson-3";
set_elf_platform(cpu, "loongson3a");
set_isa(c, MIPS_CPU_ISA_M64R1);
c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
MIPS_ASE_LOONGSON_EXT);
break;
case PRID_REV_LOONGSON3B_R1:
case PRID_REV_LOONGSON3B_R2:
c->cputype = CPU_LOONGSON64;
__cpu_name[cpu] = "ICT Loongson-3";
set_elf_platform(cpu, "loongson3b");
set_isa(c, MIPS_CPU_ISA_M64R1);
c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
MIPS_ASE_LOONGSON_EXT);
break;
}
c->options = R4K_OPTS |
MIPS_CPU_FPU | MIPS_CPU_LLSC |
MIPS_CPU_32FPR;
c->tlbsize = 64;
set_cpu_asid_mask(c, MIPS_ENTRYHI_ASID);
c->writecombine = _CACHE_UNCACHED_ACCELERATED;
break;
case PRID_IMP_LOONGSON_32: /* Loongson-1 */
decode_configs(c);
c->cputype = CPU_LOONGSON32;
switch (c->processor_id & PRID_REV_MASK) {
case PRID_REV_LOONGSON1B:
__cpu_name[cpu] = "Loongson 1B";
break;
}
break;
}
}
static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
{
c->writecombine = _CACHE_UNCACHED_ACCELERATED;
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_QEMU_GENERIC:
c->writecombine = _CACHE_UNCACHED;
c->cputype = CPU_QEMU_GENERIC;
__cpu_name[cpu] = "MIPS GENERIC QEMU";
break;
case PRID_IMP_4KC:
c->cputype = CPU_4KC;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 4Kc";
break;
case PRID_IMP_4KEC:
case PRID_IMP_4KECR2:
c->cputype = CPU_4KEC;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 4KEc";
break;
case PRID_IMP_4KSC:
case PRID_IMP_4KSD:
c->cputype = CPU_4KSC;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 4KSc";
break;
case PRID_IMP_5KC:
c->cputype = CPU_5KC;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 5Kc";
break;
case PRID_IMP_5KE:
c->cputype = CPU_5KE;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 5KE";
break;
case PRID_IMP_20KC:
c->cputype = CPU_20KC;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 20Kc";
break;
case PRID_IMP_24K:
c->cputype = CPU_24K;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 24Kc";
break;
case PRID_IMP_24KE:
c->cputype = CPU_24K;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 24KEc";
break;
case PRID_IMP_25KF:
c->cputype = CPU_25KF;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 25Kc";
break;
case PRID_IMP_34K:
c->cputype = CPU_34K;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 34Kc";
cpu_set_mt_per_tc_perf(c);
break;
case PRID_IMP_74K:
c->cputype = CPU_74K;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 74Kc";
break;
case PRID_IMP_M14KC:
c->cputype = CPU_M14KC;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS M14Kc";
break;
case PRID_IMP_M14KEC:
c->cputype = CPU_M14KEC;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS M14KEc";
break;
case PRID_IMP_1004K:
c->cputype = CPU_1004K;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 1004Kc";
cpu_set_mt_per_tc_perf(c);
break;
case PRID_IMP_1074K:
c->cputype = CPU_1074K;
c->writecombine = _CACHE_UNCACHED;
__cpu_name[cpu] = "MIPS 1074Kc";
break;
case PRID_IMP_INTERAPTIV_UP:
c->cputype = CPU_INTERAPTIV;
__cpu_name[cpu] = "MIPS interAptiv";
cpu_set_mt_per_tc_perf(c);
break;
case PRID_IMP_INTERAPTIV_MP:
c->cputype = CPU_INTERAPTIV;
__cpu_name[cpu] = "MIPS interAptiv (multi)";
cpu_set_mt_per_tc_perf(c);
break;
case PRID_IMP_PROAPTIV_UP:
c->cputype = CPU_PROAPTIV;
__cpu_name[cpu] = "MIPS proAptiv";
break;
case PRID_IMP_PROAPTIV_MP:
c->cputype = CPU_PROAPTIV;
__cpu_name[cpu] = "MIPS proAptiv (multi)";
break;
case PRID_IMP_P5600:
c->cputype = CPU_P5600;
__cpu_name[cpu] = "MIPS P5600";
break;
case PRID_IMP_P6600:
c->cputype = CPU_P6600;
__cpu_name[cpu] = "MIPS P6600";
break;
case PRID_IMP_I6400:
c->cputype = CPU_I6400;
__cpu_name[cpu] = "MIPS I6400";
break;
case PRID_IMP_I6500:
c->cputype = CPU_I6500;
__cpu_name[cpu] = "MIPS I6500";
break;
case PRID_IMP_M5150:
c->cputype = CPU_M5150;
__cpu_name[cpu] = "MIPS M5150";
break;
case PRID_IMP_M6250:
c->cputype = CPU_M6250;
__cpu_name[cpu] = "MIPS M6250";
break;
}
decode_configs(c);
spram_config();
mm_config(c);
switch (__get_cpu_type(c->cputype)) {
case CPU_M5150:
case CPU_P5600:
set_isa(c, MIPS_CPU_ISA_M32R5);
break;
case CPU_I6500:
c->options |= MIPS_CPU_SHARED_FTLB_ENTRIES;
fallthrough;
case CPU_I6400:
c->options |= MIPS_CPU_SHARED_FTLB_RAM;
fallthrough;
default:
break;
}
/* Recent MIPS cores use the implementation-dependent ExcCode 16 for
* cache/FTLB parity exceptions.
*/
switch (__get_cpu_type(c->cputype)) {
case CPU_PROAPTIV:
case CPU_P5600:
case CPU_P6600:
case CPU_I6400:
case CPU_I6500:
c->options |= MIPS_CPU_FTLBPAREX;
break;
}
}
static inline void cpu_probe_alchemy(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_AU1_REV1:
case PRID_IMP_AU1_REV2:
c->cputype = CPU_ALCHEMY;
switch ((c->processor_id >> 24) & 0xff) {
case 0:
__cpu_name[cpu] = "Au1000";
break;
case 1:
__cpu_name[cpu] = "Au1500";
break;
case 2:
__cpu_name[cpu] = "Au1100";
break;
case 3:
__cpu_name[cpu] = "Au1550";
break;
case 4:
__cpu_name[cpu] = "Au1200";
if ((c->processor_id & PRID_REV_MASK) == 2)
__cpu_name[cpu] = "Au1250";
break;
case 5:
__cpu_name[cpu] = "Au1210";
break;
default:
__cpu_name[cpu] = "Au1xxx";
break;
}
break;
}
}
static inline void cpu_probe_sibyte(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
c->writecombine = _CACHE_UNCACHED_ACCELERATED;
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_SB1:
c->cputype = CPU_SB1;
__cpu_name[cpu] = "SiByte SB1";
/* FPU in pass1 is known to have issues. */
if ((c->processor_id & PRID_REV_MASK) < 0x02)
c->options &= ~(MIPS_CPU_FPU | MIPS_CPU_32FPR);
break;
case PRID_IMP_SB1A:
c->cputype = CPU_SB1A;
__cpu_name[cpu] = "SiByte SB1A";
break;
}
}
static inline void cpu_probe_sandcraft(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_SR71000:
c->cputype = CPU_SR71000;
__cpu_name[cpu] = "Sandcraft SR71000";
c->scache.ways = 8;
c->tlbsize = 64;
break;
}
}
static inline void cpu_probe_nxp(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_PR4450:
c->cputype = CPU_PR4450;
__cpu_name[cpu] = "Philips PR4450";
set_isa(c, MIPS_CPU_ISA_M32R1);
break;
}
}
static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_BMIPS32_REV4:
case PRID_IMP_BMIPS32_REV8:
c->cputype = CPU_BMIPS32;
__cpu_name[cpu] = "Broadcom BMIPS32";
set_elf_platform(cpu, "bmips32");
break;
case PRID_IMP_BMIPS3300:
case PRID_IMP_BMIPS3300_ALT:
case PRID_IMP_BMIPS3300_BUG:
c->cputype = CPU_BMIPS3300;
__cpu_name[cpu] = "Broadcom BMIPS3300";
set_elf_platform(cpu, "bmips3300");
reserve_exception_space(0x400, VECTORSPACING * 64);
break;
case PRID_IMP_BMIPS43XX: {
int rev = c->processor_id & PRID_REV_MASK;
if (rev >= PRID_REV_BMIPS4380_LO &&
rev <= PRID_REV_BMIPS4380_HI) {
c->cputype = CPU_BMIPS4380;
__cpu_name[cpu] = "Broadcom BMIPS4380";
set_elf_platform(cpu, "bmips4380");
c->options |= MIPS_CPU_RIXI;
reserve_exception_space(0x400, VECTORSPACING * 64);
} else {
c->cputype = CPU_BMIPS4350;
__cpu_name[cpu] = "Broadcom BMIPS4350";
set_elf_platform(cpu, "bmips4350");
}
break;
}
case PRID_IMP_BMIPS5000:
case PRID_IMP_BMIPS5200:
c->cputype = CPU_BMIPS5000;
if ((c->processor_id & PRID_IMP_MASK) == PRID_IMP_BMIPS5200)
__cpu_name[cpu] = "Broadcom BMIPS5200";
else
__cpu_name[cpu] = "Broadcom BMIPS5000";
set_elf_platform(cpu, "bmips5000");
c->options |= MIPS_CPU_ULRI | MIPS_CPU_RIXI;
reserve_exception_space(0x1000, VECTORSPACING * 64);
break;
}
}
static inline void cpu_probe_cavium(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_CAVIUM_CN38XX:
case PRID_IMP_CAVIUM_CN31XX:
case PRID_IMP_CAVIUM_CN30XX:
c->cputype = CPU_CAVIUM_OCTEON;
__cpu_name[cpu] = "Cavium Octeon";
goto platform;
case PRID_IMP_CAVIUM_CN58XX:
case PRID_IMP_CAVIUM_CN56XX:
case PRID_IMP_CAVIUM_CN50XX:
case PRID_IMP_CAVIUM_CN52XX:
c->cputype = CPU_CAVIUM_OCTEON_PLUS;
__cpu_name[cpu] = "Cavium Octeon+";
platform:
set_elf_platform(cpu, "octeon");
break;
case PRID_IMP_CAVIUM_CN61XX:
case PRID_IMP_CAVIUM_CN63XX:
case PRID_IMP_CAVIUM_CN66XX:
case PRID_IMP_CAVIUM_CN68XX:
case PRID_IMP_CAVIUM_CNF71XX:
c->cputype = CPU_CAVIUM_OCTEON2;
__cpu_name[cpu] = "Cavium Octeon II";
set_elf_platform(cpu, "octeon2");
break;
case PRID_IMP_CAVIUM_CN70XX:
case PRID_IMP_CAVIUM_CN73XX:
case PRID_IMP_CAVIUM_CNF75XX:
case PRID_IMP_CAVIUM_CN78XX:
c->cputype = CPU_CAVIUM_OCTEON3;
__cpu_name[cpu] = "Cavium Octeon III";
set_elf_platform(cpu, "octeon3");
break;
default:
printk(KERN_INFO "Unknown Octeon chip!\n");
c->cputype = CPU_UNKNOWN;
break;
}
}
#ifdef CONFIG_CPU_LOONGSON64
#include <loongson_regs.h>
static inline void decode_cpucfg(struct cpuinfo_mips *c)
{
u32 cfg1 = read_cpucfg(LOONGSON_CFG1);
u32 cfg2 = read_cpucfg(LOONGSON_CFG2);
u32 cfg3 = read_cpucfg(LOONGSON_CFG3);
if (cfg1 & LOONGSON_CFG1_MMI)
c->ases |= MIPS_ASE_LOONGSON_MMI;
if (cfg2 & LOONGSON_CFG2_LEXT1)
c->ases |= MIPS_ASE_LOONGSON_EXT;
if (cfg2 & LOONGSON_CFG2_LEXT2)
c->ases |= MIPS_ASE_LOONGSON_EXT2;
if (cfg2 & LOONGSON_CFG2_LSPW) {
c->options |= MIPS_CPU_LDPTE;
c->guest.options |= MIPS_CPU_LDPTE;
}
if (cfg3 & LOONGSON_CFG3_LCAMP)
c->ases |= MIPS_ASE_LOONGSON_CAM;
}
static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
/* All Loongson processors covered here define ExcCode 16 as GSExc. */
c->options |= MIPS_CPU_GSEXCEX;
switch (c->processor_id & PRID_IMP_MASK) {
case PRID_IMP_LOONGSON_64R: /* Loongson-64 Reduced */
switch (c->processor_id & PRID_REV_MASK) {
case PRID_REV_LOONGSON2K_R1_0:
case PRID_REV_LOONGSON2K_R1_1:
case PRID_REV_LOONGSON2K_R1_2:
case PRID_REV_LOONGSON2K_R1_3:
c->cputype = CPU_LOONGSON64;
__cpu_name[cpu] = "Loongson-2K";
set_elf_platform(cpu, "gs264e");
set_isa(c, MIPS_CPU_ISA_M64R2);
break;
}
c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_EXT |
MIPS_ASE_LOONGSON_EXT2);
break;
case PRID_IMP_LOONGSON_64C: /* Loongson-3 Classic */
switch (c->processor_id & PRID_REV_MASK) {
case PRID_REV_LOONGSON3A_R2_0:
case PRID_REV_LOONGSON3A_R2_1:
c->cputype = CPU_LOONGSON64;
__cpu_name[cpu] = "ICT Loongson-3";
set_elf_platform(cpu, "loongson3a");
set_isa(c, MIPS_CPU_ISA_M64R2);
break;
case PRID_REV_LOONGSON3A_R3_0:
case PRID_REV_LOONGSON3A_R3_1:
c->cputype = CPU_LOONGSON64;
__cpu_name[cpu] = "ICT Loongson-3";
set_elf_platform(cpu, "loongson3a");
set_isa(c, MIPS_CPU_ISA_M64R2);
break;
}
/*
* Loongson-3 Classic did not implement MIPS standard TLBINV
* but implemented TLBINVF and EHINV. As currently we're only
* using these two features, enable MIPS_CPU_TLBINV as well.
*
* Also some early Loongson-3A2000 had wrong TLB type in Config
* register, we correct it here.
*/
c->options |= MIPS_CPU_FTLB | MIPS_CPU_TLBINV | MIPS_CPU_LDPTE;
c->ases |= (MIPS_ASE_LOONGSON_MMI | MIPS_ASE_LOONGSON_CAM |
MIPS_ASE_LOONGSON_EXT | MIPS_ASE_LOONGSON_EXT2);
c->ases &= ~MIPS_ASE_VZ; /* VZ of Loongson-3A2000/3000 is incomplete */
break;
case PRID_IMP_LOONGSON_64G:
c->cputype = CPU_LOONGSON64;
__cpu_name[cpu] = "ICT Loongson-3";
set_elf_platform(cpu, "loongson3a");
set_isa(c, MIPS_CPU_ISA_M64R2);
decode_cpucfg(c);
break;
default:
panic("Unknown Loongson Processor ID!");
break;
}
}
#else
static inline void cpu_probe_loongson(struct cpuinfo_mips *c, unsigned int cpu) { }
#endif
static inline void cpu_probe_ingenic(struct cpuinfo_mips *c, unsigned int cpu)
{
decode_configs(c);
/*
* XBurst misses a config2 register, so config3 decode was skipped in
* decode_configs().
*/
decode_config3(c);
/* XBurst does not implement the CP0 counter. */
c->options &= ~MIPS_CPU_COUNTER;
BUG_ON(__builtin_constant_p(cpu_has_counter) && cpu_has_counter);
/* XBurst has virtually tagged icache */
c->icache.flags |= MIPS_CACHE_VTAG;
switch (c->processor_id & PRID_IMP_MASK) {
/* XBurst®1 with MXU1.0/MXU1.1 SIMD ISA */
case PRID_IMP_XBURST_REV1:
/*
* The XBurst core by default attempts to avoid branch target
* buffer lookups by detecting & special casing loops. This
* feature will cause BogoMIPS and lpj calculate in error.
* Set cp0 config7 bit 4 to disable this feature.
*/
set_c0_config7(MIPS_CONF7_BTB_LOOP_EN);
switch (c->processor_id & PRID_COMP_MASK) {
/*
* The config0 register in the XBurst CPUs with a processor ID of
* PRID_COMP_INGENIC_D0 report themselves as MIPS32r2 compatible,
* but they don't actually support this ISA.
*/
case PRID_COMP_INGENIC_D0:
c->isa_level &= ~MIPS_CPU_ISA_M32R2;
/* FPU is not properly detected on JZ4760(B). */
if (c->processor_id == 0x2ed0024f)
c->options |= MIPS_CPU_FPU;
fallthrough;
/*
* The config0 register in the XBurst CPUs with a processor ID of
* PRID_COMP_INGENIC_D0 or PRID_COMP_INGENIC_D1 has an abandoned
* huge page tlb mode, this mode is not compatible with the MIPS
* standard, it will cause tlbmiss and into an infinite loop
* (line 21 in the tlb-funcs.S) when starting the init process.
* After chip reset, the default is HPTLB mode, Write 0xa9000000
* to cp0 register 5 sel 4 to switch back to VTLB mode to prevent
* getting stuck.
*/
case PRID_COMP_INGENIC_D1:
write_c0_page_ctrl(XBURST_PAGECTRL_HPTLB_DIS);
break;
default:
break;
}
fallthrough;
/* XBurst®1 with MXU2.0 SIMD ISA */
case PRID_IMP_XBURST_REV2:
/* Ingenic uses the WA bit to achieve write-combine memory writes */
c->writecombine = _CACHE_CACHABLE_WA;
c->cputype = CPU_XBURST;
__cpu_name[cpu] = "Ingenic XBurst";
break;
/* XBurst®2 with MXU2.1 SIMD ISA */
case PRID_IMP_XBURST2:
c->cputype = CPU_XBURST;
__cpu_name[cpu] = "Ingenic XBurst II";
break;
default:
panic("Unknown Ingenic Processor ID!");
break;
}
}
#ifdef CONFIG_64BIT
/* For use by uaccess.h */
u64 __ua_limit;
EXPORT_SYMBOL(__ua_limit);
#endif
const char *__cpu_name[NR_CPUS];
const char *__elf_platform;
const char *__elf_base_platform;
void cpu_probe(void)
{
struct cpuinfo_mips *c = &current_cpu_data;
unsigned int cpu = smp_processor_id();
/*
* Set a default elf platform, cpu probe may later
* overwrite it with a more precise value
*/
set_elf_platform(cpu, "mips");
c->processor_id = PRID_IMP_UNKNOWN;
c->fpu_id = FPIR_IMP_NONE;
c->cputype = CPU_UNKNOWN;
c->writecombine = _CACHE_UNCACHED;
c->fpu_csr31 = FPU_CSR_RN;
c->fpu_msk31 = FPU_CSR_RSVD | FPU_CSR_ABS2008 | FPU_CSR_NAN2008;
c->processor_id = read_c0_prid();
switch (c->processor_id & PRID_COMP_MASK) {
case PRID_COMP_LEGACY:
cpu_probe_legacy(c, cpu);
break;
case PRID_COMP_MIPS:
cpu_probe_mips(c, cpu);
break;
case PRID_COMP_ALCHEMY:
cpu_probe_alchemy(c, cpu);
break;
case PRID_COMP_SIBYTE:
cpu_probe_sibyte(c, cpu);
break;
case PRID_COMP_BROADCOM:
cpu_probe_broadcom(c, cpu);
break;
case PRID_COMP_SANDCRAFT:
cpu_probe_sandcraft(c, cpu);
break;
case PRID_COMP_NXP:
cpu_probe_nxp(c, cpu);
break;
case PRID_COMP_CAVIUM:
cpu_probe_cavium(c, cpu);
break;
case PRID_COMP_LOONGSON:
cpu_probe_loongson(c, cpu);
break;
case PRID_COMP_INGENIC_13:
case PRID_COMP_INGENIC_D0:
case PRID_COMP_INGENIC_D1:
case PRID_COMP_INGENIC_E1:
cpu_probe_ingenic(c, cpu);
break;
}
BUG_ON(!__cpu_name[cpu]);
BUG_ON(c->cputype == CPU_UNKNOWN);
/*
* Platform code can force the cpu type to optimize code
* generation. In that case be sure the cpu type is correctly
* manually setup otherwise it could trigger some nasty bugs.
*/
BUG_ON(current_cpu_type() != c->cputype);
if (cpu_has_rixi) {
/* Enable the RIXI exceptions */
set_c0_pagegrain(PG_IEC);
back_to_back_c0_hazard();
/* Verify the IEC bit is set */
if (read_c0_pagegrain() & PG_IEC)
c->options |= MIPS_CPU_RIXIEX;
}
if (mips_fpu_disabled)
c->options &= ~MIPS_CPU_FPU;
if (mips_dsp_disabled)
c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P);
if (mips_htw_disabled) {
c->options &= ~MIPS_CPU_HTW;
write_c0_pwctl(read_c0_pwctl() &
~(1 << MIPS_PWCTL_PWEN_SHIFT));
}
if (c->options & MIPS_CPU_FPU)
cpu_set_fpu_opts(c);
else
cpu_set_nofpu_opts(c);
if (cpu_has_mips_r2_r6) {
c->srsets = ((read_c0_srsctl() >> 26) & 0x0f) + 1;
/* R2 has Performance Counter Interrupt indicator */
c->options |= MIPS_CPU_PCI;
}
else
c->srsets = 1;
if (cpu_has_mips_r6)
elf_hwcap |= HWCAP_MIPS_R6;
if (cpu_has_msa) {
c->msa_id = cpu_get_msa_id();
WARN(c->msa_id & MSA_IR_WRPF,
"Vector register partitioning unimplemented!");
elf_hwcap |= HWCAP_MIPS_MSA;
}
if (cpu_has_mips16)
elf_hwcap |= HWCAP_MIPS_MIPS16;
if (cpu_has_mdmx)
elf_hwcap |= HWCAP_MIPS_MDMX;
if (cpu_has_mips3d)
elf_hwcap |= HWCAP_MIPS_MIPS3D;
if (cpu_has_smartmips)
elf_hwcap |= HWCAP_MIPS_SMARTMIPS;
if (cpu_has_dsp)
elf_hwcap |= HWCAP_MIPS_DSP;
if (cpu_has_dsp2)
elf_hwcap |= HWCAP_MIPS_DSP2;
if (cpu_has_dsp3)
elf_hwcap |= HWCAP_MIPS_DSP3;
if (cpu_has_mips16e2)
elf_hwcap |= HWCAP_MIPS_MIPS16E2;
if (cpu_has_loongson_mmi)
elf_hwcap |= HWCAP_LOONGSON_MMI;
if (cpu_has_loongson_ext)
elf_hwcap |= HWCAP_LOONGSON_EXT;
if (cpu_has_loongson_ext2)
elf_hwcap |= HWCAP_LOONGSON_EXT2;
if (cpu_has_vz)
cpu_probe_vz(c);
cpu_probe_vmbits(c);
/* Synthesize CPUCFG data if running on Loongson processors;
* no-op otherwise.
*
* This looks at previously probed features, so keep this at bottom.
*/
loongson3_cpucfg_synthesize_data(c);
#ifdef CONFIG_64BIT
if (cpu == 0)
__ua_limit = ~((1ull << cpu_vmbits) - 1);
#endif
reserve_exception_space(0, 0x1000);
}
void cpu_report(void)
{
struct cpuinfo_mips *c = &current_cpu_data;
pr_info("CPU%d revision is: %08x (%s)\n",
smp_processor_id(), c->processor_id, cpu_name_string());
if (c->options & MIPS_CPU_FPU)
printk(KERN_INFO "FPU revision is: %08x\n", c->fpu_id);
if (cpu_has_msa)
pr_info("MSA revision is: %08x\n", c->msa_id);
}
void cpu_set_cluster(struct cpuinfo_mips *cpuinfo, unsigned int cluster)
{
/* Ensure the core number fits in the field */
WARN_ON(cluster > (MIPS_GLOBALNUMBER_CLUSTER >>
MIPS_GLOBALNUMBER_CLUSTER_SHF));
cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CLUSTER;
cpuinfo->globalnumber |= cluster << MIPS_GLOBALNUMBER_CLUSTER_SHF;
}
void cpu_set_core(struct cpuinfo_mips *cpuinfo, unsigned int core)
{
/* Ensure the core number fits in the field */
WARN_ON(core > (MIPS_GLOBALNUMBER_CORE >> MIPS_GLOBALNUMBER_CORE_SHF));
cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_CORE;
cpuinfo->globalnumber |= core << MIPS_GLOBALNUMBER_CORE_SHF;
}
void cpu_set_vpe_id(struct cpuinfo_mips *cpuinfo, unsigned int vpe)
{
/* Ensure the VP(E) ID fits in the field */
WARN_ON(vpe > (MIPS_GLOBALNUMBER_VP >> MIPS_GLOBALNUMBER_VP_SHF));
/* Ensure we're not using VP(E)s without support */
WARN_ON(vpe && !IS_ENABLED(CONFIG_MIPS_MT_SMP) &&
!IS_ENABLED(CONFIG_CPU_MIPSR6));
cpuinfo->globalnumber &= ~MIPS_GLOBALNUMBER_VP;
cpuinfo->globalnumber |= vpe << MIPS_GLOBALNUMBER_VP_SHF;
}