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Get binaries closer to running without an o/s

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blinkenlights now does a pretty good job emulating what happens when
binaries boot from BIOS into long mode. So it's been much easier to
debug the bare metal process and wrinkle out many issues.
This commit is contained in:
Justine Tunney 2020-10-29 04:53:20 -07:00
parent feed0d2b0e
commit 2d80bbc802
50 changed files with 974 additions and 1062 deletions
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57
tool/build/lib/op101.c
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@ -17,22 +17,79 @@
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/log/log.h"
#include "tool/build/lib/endian.h"
#include "tool/build/lib/memory.h"
#include "tool/build/lib/modrm.h"
#include "tool/build/lib/op101.h"
#include "tool/build/lib/throw.h"
#include "tool/build/lib/time.h"
static void StoreDescriptorTable(struct Machine *m, uint32_t rde,
uint16_t limit, uint64_t base) {
uint64_t l;
l = ComputeAddress(m, rde);
if (l + 10 <= m->real.n) {
Write16(m->real.p + l, limit);
if (Rexw(rde)) {
Write64(m->real.p + l + 2, base);
SetWriteAddr(m, l, 10);
} else if (!Osz(rde)) {
Write32(m->real.p + l + 2, base);
SetWriteAddr(m, l, 6);
} else {
Write16(m->real.p + l + 2, base);
SetWriteAddr(m, l, 4);
}
} else {
ThrowSegmentationFault(m, l);
}
}
static void LoadDescriptorTable(struct Machine *m, uint32_t rde,
uint16_t *out_limit, uint64_t *out_base) {
uint16_t limit;
uint64_t l, base;
l = ComputeAddress(m, rde);
if (l + 10 <= m->real.n) {
limit = Read16(m->real.p + l);
if (Rexw(rde)) {
base = Read64(m->real.p + l + 2) & 0x00ffffff;
SetReadAddr(m, l, 10);
} else if (!Osz(rde)) {
base = Read32(m->real.p + l + 2);
SetReadAddr(m, l, 6);
} else {
base = Read16(m->real.p + l + 2);
SetReadAddr(m, l, 4);
}
if (base + limit <= m->real.n) {
*out_limit = limit;
*out_base = base;
} else {
ThrowProtectionFault(m);
}
} else {
ThrowSegmentationFault(m, l);
}
}
static void SgdtMs(struct Machine *m, uint32_t rde) {
StoreDescriptorTable(m, rde, m->gdt_limit, m->gdt_base);
}
static void LgdtMs(struct Machine *m, uint32_t rde) {
LoadDescriptorTable(m, rde, &m->gdt_limit, &m->gdt_base);
LOGF("set gdt %p lim %,d", m->gdt_base, m->gdt_limit);
}
static void SidtMs(struct Machine *m, uint32_t rde) {
StoreDescriptorTable(m, rde, m->idt_limit, m->idt_base);
}
static void LidtMs(struct Machine *m, uint32_t rde) {
LoadDescriptorTable(m, rde, &m->idt_limit, &m->idt_base);
LOGF("set idt %p lim %,d", m->idt_base, m->idt_limit);
}
static void Monitor(struct Machine *m, uint32_t rde) {