path: root/src/fw/biostables.c

// Support for manipulating bios tables (pir, mptable, acpi, smbios).
//
// Copyright (C) 2008,2009  Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU LGPLv3 license.

#include "byteorder.h" // le32_to_cpu
#include "config.h" // CONFIG_*
#include "malloc.h" // malloc_fseg
#include "output.h" // dprintf
#include "hw/pci.h" // pci_config_writeb
#include "std/acpi.h" // struct rsdp_descriptor
#include "std/mptable.h" // MPTABLE_SIGNATURE
#include "std/pirtable.h" // struct pir_header
#include "std/smbios.h" // struct smbios_entry_point
#include "string.h" // memcpy
#include "util.h" // copy_table
#include "x86.h" // outb

static void
copy_pir(void *pos)
{
    struct pir_header *p = pos;
    if (p->signature != PIR_SIGNATURE)
        return;
    if (PirAddr)
        return;
    if (p->size < sizeof(*p))
        return;
    if (checksum(pos, p->size) != 0)
        return;
    void *newpos = malloc_fseg(p->size);
    if (!newpos) {
        warn_noalloc();
        return;
    }
    dprintf(1, "Copying PIR from %p to %p\n", pos, newpos);
    memcpy(newpos, pos, p->size);
    PirAddr = newpos;
}

static void
copy_mptable(void *pos)
{
    struct mptable_floating_s *p = pos;
    if (p->signature != MPTABLE_SIGNATURE)
        return;
    if (!p->physaddr)
        return;
    if (checksum(pos, sizeof(*p)) != 0)
        return;
    u32 length = p->length * 16;
    u16 mpclength = ((struct mptable_config_s *)p->physaddr)->length;
    struct mptable_floating_s *newpos = malloc_fseg(length + mpclength);
    if (!newpos) {
        warn_noalloc();
        return;
    }
    dprintf(1, "Copying MPTABLE from %p/%x to %p\n", pos, p->physaddr, newpos);
    memcpy(newpos, pos, length);
    newpos->physaddr = (u32)newpos + length;
    newpos->checksum -= checksum(newpos, sizeof(*newpos));
    memcpy((void*)newpos + length, (void*)p->physaddr, mpclength);
}


/****************************************************************
 * ACPI
 ****************************************************************/

static int
get_acpi_rsdp_length(void *pos, unsigned size)
{
    struct rsdp_descriptor *p = pos;
    if (p->signature != RSDP_SIGNATURE)
        return -1;
    u32 length = 20;
    if (length > size)
        return -1;
    if (checksum(pos, length) != 0)
        return -1;
    if (p->revision > 1) {
        length = p->length;
        if (length > size)
            return -1;
        if (checksum(pos, length) != 0)
            return -1;
    }
    return length;
}

struct rsdp_descriptor *RsdpAddr;

static void
copy_acpi_rsdp(void *pos)
{
    if (RsdpAddr)
        return;
    int length = get_acpi_rsdp_length(pos, -1);
    if (length < 0)
        return;
    void *newpos = malloc_fseg(length);
    if (!newpos) {
        warn_noalloc();
        return;
    }
    dprintf(1, "Copying ACPI RSDP from %p to %p\n", pos, newpos);
    memcpy(newpos, pos, length);
    RsdpAddr = newpos;
}

void *find_acpi_rsdp(void)
{
    extern u8 zonefseg_start[], zonefseg_end[];
    unsigned long start = (unsigned long)zonefseg_start;
    unsigned long end = (unsigned long)zonefseg_end;
    unsigned long pos;

    for (pos = ALIGN(start, 0x10); pos <= ALIGN_DOWN(end, 0x10); pos += 0x10)
        if (get_acpi_rsdp_length((void *)pos, end - pos) >= 0)
            return (void *)pos;

    return NULL;
}

static struct fadt_descriptor_rev1 *
find_fadt(void)
{
    dprintf(4, "rsdp=%p\n", RsdpAddr);
    if (!RsdpAddr || RsdpAddr->signature != RSDP_SIGNATURE)
        return NULL;
    struct rsdt_descriptor_rev1 *rsdt = (void*)RsdpAddr->rsdt_physical_address;
    dprintf(4, "rsdt=%p\n", rsdt);
    if (!rsdt || rsdt->signature != RSDT_SIGNATURE)
        return NULL;
    void *end = (void*)rsdt + rsdt->length;
    int i;
    for (i=0; (void*)&rsdt->table_offset_entry[i] < end; i++) {
        struct fadt_descriptor_rev1 *fadt = (void*)rsdt->table_offset_entry[i];
        if (!fadt || fadt->signature != FACP_SIGNATURE)
            continue;
        dprintf(4, "fadt=%p\n", fadt);
        return fadt;
    }
    dprintf(4, "no fadt found\n");
    return NULL;
}

u32
find_resume_vector(void)
{
    struct fadt_descriptor_rev1 *fadt = find_fadt();
    if (!fadt)
        return 0;
    struct facs_descriptor_rev1 *facs = (void*)fadt->firmware_ctrl;
    dprintf(4, "facs=%p\n", facs);
    if (! facs || facs->signature != FACS_SIGNATURE)
        return 0;
    // Found it.
    dprintf(4, "resume addr=%d\n", facs->firmware_waking_vector);
    return facs->firmware_waking_vector;
}

static struct acpi_20_generic_address acpi_reset_reg;
static u8 acpi_reset_val;
u32 acpi_pm1a_cnt VARFSEG;

#define acpi_ga_to_bdf(addr) pci_to_bdf(0, (addr >> 32) & 0xffff, (addr >> 16) & 0xffff)

void
acpi_reboot(void)
{
    // Check it passed the sanity checks in acpi_set_reset_reg() and was set
    if (acpi_reset_reg.register_bit_width != 8)
        return;

    u64 addr = le64_to_cpu(acpi_reset_reg.address);

    dprintf(1, "ACPI hard reset %d:%llx (%x)\n",
            acpi_reset_reg.address_space_id, addr, acpi_reset_val);

    switch (acpi_reset_reg.address_space_id) {
    case 0: // System Memory
	writeb((void *)(u32)addr, acpi_reset_val);
        break;
    case 1: // System I/O
        outb(acpi_reset_val, addr);
        break;
    case 2: // PCI config space
        pci_config_writeb(acpi_ga_to_bdf(addr), addr & 0xffff, acpi_reset_val);
        break;
    }
}

static void
acpi_set_reset_reg(struct acpi_20_generic_address *reg, u8 val)
{
    if (!reg || reg->address_space_id > 2 ||
        reg->register_bit_width != 8 || reg->register_bit_offset)
        return;

    acpi_reset_reg = *reg;
    acpi_reset_val = val;
}

void
find_acpi_features(void)
{
    struct fadt_descriptor_rev1 *fadt = find_fadt();
    if (!fadt)
        return;
    u32 pm_tmr = le32_to_cpu(fadt->pm_tmr_blk);
    u32 pm1a_cnt = le32_to_cpu(fadt->pm1a_cnt_blk);
    dprintf(4, "pm_tmr_blk=%x\n", pm_tmr);
    if (pm_tmr)
        pmtimer_setup(pm_tmr);
    if (pm1a_cnt)
        acpi_pm1a_cnt = pm1a_cnt;

    // Theoretically we should check the 'reset_reg_sup' flag, but Windows
    // doesn't and thus nobody seems to *set* it. If the table is large enough
    // to include it, let the sanity checks in acpi_set_reset_reg() suffice.
    if (fadt->length >= 129) {
        void *p = fadt;
        acpi_set_reset_reg(p + 116, *(u8 *)(p + 128));
    }
}


/****************************************************************
 * SMBIOS
 ****************************************************************/

void
copy_smbios(void *pos)
{
    if (SMBiosAddr)
        return;
    struct smbios_entry_point *p = pos;
    if (memcmp(p->anchor_string, "_SM_", 4))
        return;
    if (checksum(pos, 0x10) != 0)
        return;
    if (memcmp(p->intermediate_anchor_string, "_DMI_", 5))
        return;
    if (checksum(pos+0x10, p->length-0x10) != 0)
        return;
    struct smbios_entry_point *newpos = malloc_fseg(p->length);
    if (!newpos) {
        warn_noalloc();
        return;
    }
    dprintf(1, "Copying SMBIOS entry point from %p to %p\n", pos, newpos);
    memcpy(newpos, pos, p->length);
    SMBiosAddr = newpos;
}

void
copy_table(void *pos)
{
    copy_pir(pos);
    copy_mptable(pos);
    copy_acpi_rsdp(pos);
    copy_smbios(pos);
}