Files
jsix_import/src/kernel/cpu.cpp
Justin C. Miller a5f72edf82 [kernel] Add in_hv cpu "feature" flag
Reformat the cpu_features.inc file and add the `in_hv` feature that is
supposedly set by hypervisors when running in emulation. QEMU does not
set it.

Tags: cpuid
2020-06-01 23:33:30 -07:00

117 lines
3.1 KiB
C++

#include <stdint.h>
#include "kutil/memory.h"
#include "cpu.h"
#include "log.h"
cpu_data bsp_cpu_data;
static constexpr uint32_t cpuid_extended = 0x80000000;
inline static void
__cpuid(
uint32_t leaf,
uint32_t subleaf,
uint32_t *eax,
uint32_t *ebx = nullptr,
uint32_t *ecx = nullptr,
uint32_t *edx = nullptr)
{
uint32_t a, b, c, d;
__asm__ __volatile__ ( "cpuid"
: "=a"(a), "=b"(b), "=c"(c), "=d"(d)
: "a"(leaf), "c"(subleaf)
);
if (eax) *eax = a;
if (ebx) *ebx = b;
if (ecx) *ecx = c;
if (edx) *edx = d;
}
cpu_id::cpu_id() :
m_features(0)
{
__cpuid(0, 0,
&m_high_basic,
reinterpret_cast<uint32_t *>(&m_vendor_id[0]),
reinterpret_cast<uint32_t *>(&m_vendor_id[8]),
reinterpret_cast<uint32_t *>(&m_vendor_id[4]));
__cpuid(cpuid_extended, 0, &m_high_ext);
if (m_high_ext >= cpuid_extended + 4) {
__cpuid(cpuid_extended + 2, 0,
reinterpret_cast<uint32_t *>(&m_brand_name[0]),
reinterpret_cast<uint32_t *>(&m_brand_name[4]),
reinterpret_cast<uint32_t *>(&m_brand_name[8]),
reinterpret_cast<uint32_t *>(&m_brand_name[12]));
__cpuid(cpuid_extended + 3, 0,
reinterpret_cast<uint32_t *>(&m_brand_name[16]),
reinterpret_cast<uint32_t *>(&m_brand_name[20]),
reinterpret_cast<uint32_t *>(&m_brand_name[24]),
reinterpret_cast<uint32_t *>(&m_brand_name[28]));
__cpuid(cpuid_extended + 4, 0,
reinterpret_cast<uint32_t *>(&m_brand_name[32]),
reinterpret_cast<uint32_t *>(&m_brand_name[36]),
reinterpret_cast<uint32_t *>(&m_brand_name[40]),
reinterpret_cast<uint32_t *>(&m_brand_name[44]));
} else {
m_brand_name[0] = 0;
}
}
cpu_id::regs
cpu_id::get(uint32_t leaf, uint32_t sub) const
{
regs ret {0, 0, 0, 0};
if ((leaf & cpuid_extended) == 0 && leaf > m_high_basic) return ret;
if ((leaf & cpuid_extended) != 0 && leaf > m_high_ext) return ret;
__cpuid(leaf, sub, &ret.eax, &ret.ebx, &ret.ecx, &ret.edx);
return ret;
}
void
cpu_id::validate()
{
bool fail = false;
uint32_t leaf = 0;
uint32_t sub = 0;
regs r;
log::info(logs::boot, "CPU: %s", brand_name());
log::debug(logs::boot, " Vendor is %s", vendor_id());
log::debug(logs::boot, " Higest basic CPUID: 0x%02x", highest_basic());
log::debug(logs::boot, " Higest ext CPUID: 0x%02x", highest_ext() & ~cpuid_extended);
#define CPU_FEATURE_OPT(name, feat_leaf, feat_sub, regname, bit) \
if (leaf != feat_leaf || sub != feat_sub) { \
leaf = feat_leaf; sub = feat_sub; r = get(leaf, sub); \
} \
if (r.regname & (1ull << bit)) \
m_features |= (1ull << static_cast<uint64_t>(cpu_feature::name)); \
log::debug(logs::boot, " Supports %9s: %s", #name, (r.regname & (1ull << bit)) ? "yes" : "no");
#define CPU_FEATURE_REQ(name, feat_leaf, feat_sub, regname, bit) \
CPU_FEATURE_OPT(name, feat_leaf, feat_sub, regname, bit); \
if ((r.regname & (1ull << bit)) == 0) { \
log::error(logs::boot, "CPU missing required feature " #name); \
fail = true; \
}
#include "cpu_features.inc"
#undef CPU_FEATURE_OPT
#undef CPU_FEATURE_REQ
if (fail)
log::fatal(logs::boot, "CPU not supported.");
}
bool
cpu_id::has_feature(cpu_feature feat)
{
return (m_features & (1 << static_cast<uint64_t>(feat))) != 0;
}