acpi_table_header_t *mon_acpi_locate_table(char *sig)
{
acpi_table_rsdp_t *rsdp = NULL;
void *table = NULL;
/* Try 0x0 first for getting rsdp table */
rsdp = scan_for_rsdp(acpi_map_memory(0), 0x400);
if (NULL == rsdp) {
/* Try 0xE0000 */
MON_LOG(mask_anonymous, level_trace,
"Try 0xE0000 for ACPI RSDP table\n");
rsdp = scan_for_rsdp(acpi_map_memory(0xE0000), 0x1FFFF);
}
if (NULL == rsdp) {
MON_LOG(mask_anonymous,
level_error,
"Could not find the rsdp table\n");
return NULL;
}
MON_LOG(mask_anonymous, level_trace, "rsdp address %p\n", rsdp);
/* Get the specified table from rsdp */
table = get_acpi_table_from_rsdp(rsdp, sig);
return table;
}
static const struct acpi_rsdp *find_rsdp(void)
{
uint32_t ebda;
const struct acpi_rsdp *rsdp;
ebda = (*(uint16_t *)0x40e) << 4;
if (ebda >= 0x70000 && ebda < 0xa0000) {
rsdp = scan_for_rsdp(ebda, ebda+1024);
if (rsdp)
return rsdp;
}
return scan_for_rsdp(0xe0000, 0x100000);
}
/* This is where we search for SMP information in the following order
* look for a floating MP pointer
* found:
* check for a default configuration
* found:
* setup config, return
* check for a MP config table
* found:
* validate:
* good:
* parse the MP config table
* good:
* setup config, return
*
* find & validate ACPI RSDP (Root System Descriptor Pointer)
* found:
* find & validate RSDT (Root System Descriptor Table)
* found:
* find & validate MSDT
* found:
* parse the MADT table
* good:
* setup config, return
*/
void smp_find_cpus()
{
floating_pointer_struct_t *fp;
rsdp_t *rp;
rsdt_t *rt;
uint8_t *tab_ptr, *tab_end;
unsigned int *ptr;
unsigned int uiptr;
if(v->fail_safe & 3) { return; }
memset(&AP, 0, sizeof AP);
if(v->fail_safe & 8)
{
// Search for the Floating MP structure pointer
fp = scan_for_floating_ptr_struct(0x0, 0x400);
if (fp == NULL) {
fp = scan_for_floating_ptr_struct(639*0x400, 0x400);
}
if (fp == NULL) {
fp = scan_for_floating_ptr_struct(0xf0000, 0x10000);
}
if (fp == NULL) {
// Search the BIOS ESDS area
unsigned int address = *(unsigned short *)0x40E;
address <<= 4;
if (address) {
fp = scan_for_floating_ptr_struct(address, 0x400);
}
}
if (fp != NULL) {
// We have a floating MP pointer
// Is this a default configuration?
if (fp->feature[0] > 0 && fp->feature[0] <=7) {
// This is a default config so plug in the numbers
num_cpus = 2;
APIC = (volatile apic_register_t*)0xFEE00000;
cpu_num_to_apic_id[0] = 0;
cpu_num_to_apic_id[1] = 1;
return;
}
// Do we have a pointer to a MP configuration table?
if ( fp->phys_addr != 0) {
if (read_mp_config_table(fp->phys_addr)) {
// Found a good MP table, done
return;
}
}
}
}
/* No MP table so far, try to find an ACPI MADT table
* We try to use the MP table first since there is no way to distinguish
* real cores from hyper-threads in the MADT */
/* Search for the RSDP */
rp = scan_for_rsdp(0xE0000, 0x20000);
if (rp == NULL) {
/* Search the BIOS ESDS area */
unsigned int address = *(unsigned short *)0x40E;
address <<= 4;
if (address) {
rp = scan_for_rsdp(address, 0x400);
}
}
if (rp == NULL) {
/* RSDP not found, give up */
return;
}
/* Found the RSDP, now get either the RSDT or XSDT */
if (rp->revision >= 2) {
rt = (rsdt_t *)rp->xrsdt[0];
if (rt == 0) {
return;
}
// Validate the XSDT
if (*(unsigned int *)rt != XSDTSignature) {
return;
}
if ( checksum((unsigned char*)rt, rt->length) != 0) {
return;
}
} else {
rt = (rsdt_t *)rp->rsdt;
if (rt == 0) {
return;
}
/* Validate the RSDT */
if (*(unsigned int *)rt != RSDTSignature) {
return;
}
if ( checksum((unsigned char*)rt, rt->length) != 0) {
return;
}
}
/* Scan the RSDT or XSDT for a pointer to the MADT */
tab_ptr = ((uint8_t*)rt) + sizeof(rsdt_t);
tab_end = ((uint8_t*)rt) + rt->length;
while (tab_ptr < tab_end) {
uiptr = *((unsigned int *)tab_ptr);
ptr = (unsigned int *)uiptr;
/* Check for the MADT signature */
if (ptr && *ptr == MADTSignature) {
/* Found it, now parse it */
if (parse_madt((uintptr_t)ptr)) {
return;
}
}
tab_ptr += 4;
}
}
