minix/kernel/arch/i386/acpi.c
2012-03-25 21:58:14 +02:00

283 lines
5.7 KiB
C

#include <string.h>
#include "kernel/kernel.h"
#include "acpi.h"
#include "arch_proto.h"
typedef int ((* acpi_read_t)(phys_bytes addr, void * buff, size_t size));
struct acpi_rsdp acpi_rsdp;
static acpi_read_t read_func;
#define MAX_RSDT 35 /* ACPI defines 35 signatures */
static struct acpi_rsdt {
struct acpi_sdt_header hdr;
u32_t data[MAX_RSDT];
} rsdt;
static struct {
char signature [ACPI_SDT_SIGNATURE_LEN + 1];
size_t length;
} sdt_trans[MAX_RSDT];
static int sdt_count;
static int acpi_check_csum(struct acpi_sdt_header * tb, size_t size)
{
u8_t total = 0;
int i;
for (i = 0; i < size; i++)
total += ((unsigned char *)tb)[i];
return total == 0 ? 0 : -1;
}
static int acpi_check_signature(const char * orig, const char * match)
{
return strncmp(orig, match, ACPI_SDT_SIGNATURE_LEN);
}
static int acpi_read_sdt_at(phys_bytes addr,
struct acpi_sdt_header * tb,
size_t size,
const char * name)
{
struct acpi_sdt_header hdr;
/* if NULL is supplied, we only return the size of the table */
if (tb == NULL) {
if (read_func(addr, &hdr, sizeof(struct acpi_sdt_header))) {
printf("ERROR acpi cannot read %s header\n", name);
return -1;
}
return hdr.length;
}
if (read_func(addr, tb, sizeof(struct acpi_sdt_header))) {
printf("ERROR acpi cannot read %s header\n", name);
return -1;
}
if (acpi_check_signature(tb->signature, name)) {
printf("ERROR acpi %s signature does not match\n", name);
return -1;
}
if (size < tb->length) {
printf("ERROR acpi buffer too small for %s\n", name);
return -1;
}
if (read_func(addr, tb, size)) {
printf("ERROR acpi cannot read %s\n", name);
return -1;
}
if (acpi_check_csum(tb, tb->length)) {
printf("ERROR acpi %s checksum does not match\n", name);
return -1;
}
return tb->length;
}
phys_bytes acpi_get_table_base(const char * name)
{
int i;
for(i = 0; i < sdt_count; i++) {
if (strncmp(name, sdt_trans[i].signature,
ACPI_SDT_SIGNATURE_LEN) == 0)
return (phys_bytes) rsdt.data[i];
}
return (phys_bytes) NULL;
}
size_t acpi_get_table_length(const char * name)
{
int i;
for(i = 0; i < sdt_count; i++) {
if (strncmp(name, sdt_trans[i].signature,
ACPI_SDT_SIGNATURE_LEN) == 0)
return sdt_trans[i].length;
}
return 0;
}
static void * acpi_madt_get_typed_item(struct acpi_madt_hdr * hdr,
unsigned char type,
unsigned idx)
{
u8_t * t, * end;
int i;
t = (u8_t *) hdr + sizeof(struct acpi_madt_hdr);
end = (u8_t *) hdr + hdr->hdr.length;
i = 0;
while(t < end) {
if (type == ((struct acpi_madt_item_hdr *) t)->type) {
if (i == idx)
return t;
else
i++;
}
t += ((struct acpi_madt_item_hdr *) t)->length;
}
return NULL;
}
#if 0
static void * acpi_madt_get_item(struct acpi_madt_hdr * hdr,
unsigned idx)
{
u8_t * t, * end;
int i;
t = (u8_t *) hdr + sizeof(struct acpi_madt_hdr);
end = (u8_t *) hdr + hdr->hdr.length;
for(i = 0 ; i <= idx && t < end; i++) {
if (i == idx)
return t;
t += ((struct acpi_madt_item_hdr *) t)->length;
}
return NULL;
}
#endif
static int acpi_rsdp_test(void * buff)
{
struct acpi_rsdp * rsdp = (struct acpi_rsdp *) buff;
if (!platform_tbl_checksum_ok(buff, 20))
return 0;
if (strncmp(rsdp->signature, "RSD PTR ", 8))
return 0;
return 1;
}
static int get_acpi_rsdp(void)
{
u16_t ebda;
/*
* Read 40:0Eh - to find the starting address of the EBDA.
*/
phys_copy (0x40E, vir2phys(&ebda), sizeof(ebda));
if (ebda) {
ebda <<= 4;
if(platform_tbl_ptr(ebda, ebda + 0x400, 16, &acpi_rsdp,
sizeof(acpi_rsdp), &machine.acpi_rsdp,
acpi_rsdp_test))
return 1;
}
/* try BIOS read only mem space */
if(platform_tbl_ptr(0xE0000, 0x100000, 16, &acpi_rsdp,
sizeof(acpi_rsdp), &machine.acpi_rsdp,
acpi_rsdp_test))
return 1;
machine.acpi_rsdp = 0; /* RSDP cannot be found at this address therefore
it is a valid negative value */
return 0;
}
static int acpi_read_kernel(phys_bytes addr, void * buff, size_t size)
{
phys_copy(addr, vir2phys(buff), size);
return 0;
}
void acpi_init(void)
{
int s, i;
read_func = acpi_read_kernel;
if (!get_acpi_rsdp()) {
printf("WARNING : Cannot configure ACPI\n");
return;
}
s = acpi_read_sdt_at(acpi_rsdp.rsdt_addr, (struct acpi_sdt_header *) &rsdt,
sizeof(struct acpi_rsdt), ACPI_SDT_SIGNATURE(RSDT));
sdt_count = (s - sizeof(struct acpi_sdt_header)) / sizeof(u32_t);
for (i = 0; i < sdt_count; i++) {
struct acpi_sdt_header hdr;
int j;
if (read_func(rsdt.data[i], &hdr, sizeof(struct acpi_sdt_header))) {
printf("ERROR acpi cannot read header at 0x%x\n",
rsdt.data[i]);
return;
}
for (j = 0 ; j < ACPI_SDT_SIGNATURE_LEN; j++)
sdt_trans[i].signature[j] = hdr.signature[j];
sdt_trans[i].signature[ACPI_SDT_SIGNATURE_LEN] = '\0';
sdt_trans[i].length = hdr.length;
}
}
struct acpi_madt_ioapic * acpi_get_ioapic_next(void)
{
static unsigned idx = 0;
static struct acpi_madt_hdr * madt_hdr;
struct acpi_madt_ioapic * ret;
if (idx == 0) {
madt_hdr = (struct acpi_madt_hdr *)
phys2vir(acpi_get_table_base("APIC"));
if (madt_hdr == NULL)
return NULL;
}
ret = (struct acpi_madt_ioapic *)
acpi_madt_get_typed_item(madt_hdr, ACPI_MADT_TYPE_IOAPIC, idx);
if (ret)
idx++;
return ret;
}
struct acpi_madt_lapic * acpi_get_lapic_next(void)
{
static unsigned idx = 0;
static struct acpi_madt_hdr * madt_hdr;
struct acpi_madt_lapic * ret;
if (idx == 0) {
madt_hdr = (struct acpi_madt_hdr *)
phys2vir(acpi_get_table_base("APIC"));
if (madt_hdr == NULL)
return NULL;
}
for (;;) {
ret = (struct acpi_madt_lapic *)
acpi_madt_get_typed_item(madt_hdr,
ACPI_MADT_TYPE_LAPIC, idx);
if (!ret)
break;
idx++;
/* report only usable CPUs */
if (ret->flags & 1)
break;
}
return ret;
}