Enumerating ACPI tables for MADT (to process IOAPIC). Refactored ACPI…

… table parsing code. Corrected EBDA address loading. Added some helper functions.

acpi.c

@@ -14,28 +14,83 @@
 #include "krnlconst.h"
 #include "debug.h"
 #include "type.h"
+#include "util.h"
+#include "system.h"
 
 extern int ebda;
+extern int ioapic_base_register;
+extern int ioapic_gsi_base;
 
 typedef struct _RSD {
 
  char signature[8];
- byte checksum;
+ u8 checksum;
  char OEMID[6];
- byte revision;
- int rsdt_address;
+ u8 revision;
+ u32 rsdt_address;
 }__attribute__((packed)) RSD;
 
-#define CHECK_RSD_PTR(p) (p[0]=='R' && \
- p[1]=='S' && \
- p[2]=='D' && \
- p[3]==' ' && \
- p[4]=='P' && \
- p[5]=='T' && \
- p[6]=='R' && \
- p[7]==' ')
+typedef struct _ACPI_TABLE {
 
-RSD *rsd;
+ char signature[4];
+ u32 length;
+ u8 revision;
+ u8 checksum;
+ char OEMID[6];
+ char OEM_table_id[8];
+ u32 OEM_revision;
+ u32 creator_id;
+ u32 creator_revision;
+}__attribute__((packed)) ACPI_TABLE;
+
+typedef struct _APIC_TABLE {
+
+ char type;
+ char length;
+
+ union {
+ struct {
+ u8 uid;
+ u8 apic_id;
+ u32 flags;
+ }__attribute__((packed)) processor_lapic;
+
+ struct {
+ u8 id;
+ u8 reserved;
+ u32 address;
+ u32 gsi_base;
+ }__attribute__((packed)) ioapic;
+
+ struct {
+ u8 bus;
+ u8 source;
+ u32 gsi;
+ u16 flags;
+ }__attribute__((packed)) int_src_override;
+
+ struct {
+ u16 flags;
+ u32 gsi;
+ }__attribute__((packed)) nmi_source;
+
+ struct {
+ u8 uid;
+ u16 flags;
+ u8 lapic_lint;
+ }__attribute__((packed)) lapic_nmi;
+ } info;
+
+}__attribute__((packed)) APIC_TABLE;
+
+#define RSDPTR_STR "RSD PTR"
+#define APIC_STR "APIC"
+
+RSD *rsdp;
+ACPI_TABLE *rsdt;
+ACPI_TABLE **acpi_tables;
+
+int num_acpi_tables;
 
 bool acpi_find_rsdp() {
 
@@ -58,10 +113,10 @@ bool acpi_find_rsdp() {
  }
  }
 
- if (CHECK_RSD_PTR(cur->signature)) {
+ if (!memcmp(cur->signature, RSDPTR_STR, strlen(RSDPTR_STR))) {
 
- rsd = cur;
- printf(KERNEL_INFO, "RSD PTR: %p\n", (long)rsd-KERNEL_VIRT_ADDR);
+ rsdp = cur;
+ printf(KERNEL_INFO, "RSDP: %p\n", (long)rsdp-KERNEL_VIRT_ADDR);
  return true;
  }
 
@@ -71,13 +126,79 @@ bool acpi_find_rsdp() {
  return false;
 }
 
+void acpi_process_madt(ACPI_TABLE *madt) {
+
+ int remaining_bytes;
+ APIC_TABLE *apic_table;
+
+ remaining_bytes = madt->length - 44;
+ apic_table = (APIC_TABLE*)ADD2PTR(madt, 44);
+
+ do { 
+
+ remaining_bytes -= apic_table->length;
+
+ switch(apic_table->type) {
+
+ case 0:
+ {
+ // local APICs
+ } break;
+ case 1:
+ {
+ // currently supports one IOAPIC
+ if (!ioapic_base_register) {
+ ioapic_base_register = (int)apic_table->info.ioapic.address;
+ ioapic_gsi_base = (u32)apic_table->info.ioapic.gsi_base;
+ printf(KERNEL_INFO, "IOAPIC base register: %p\n", ioapic_base_register);
+ }
+ } break;
+ case 2:
+ {
+ // interrupt source override
+ } break;
+ case 3:
+ {
+ // NMI source
+ } break;
+ case 4:
+ {
+ // local APIC NMI
+ } break;
+
+ }
+
+ apic_table = (APIC_TABLE*)ADD2PTR(apic_table, apic_table->length);
+ } while(remaining_bytes);
+}
+
+void acpi_process_table(ACPI_TABLE *acpi_table) {
+
+ if (!memcmp(acpi_table->signature, APIC_STR, strlen(APIC_STR))) {
+
+ acpi_process_madt(acpi_table);
+ }
+}
+
 void acpi_init() {
 
- rsd = NULL;
+ rsdp = NULL;
+ acpi_tables = NULL;
+ ioapic_base_register = 0;
+
  if (!acpi_find_rsdp()) {
 
  printf(KERNEL_INFO, "No ACPI!!!\n");
  return;
  }
- printf(KERNEL_INFO, "RSDT: %p\n", rsd->rsdt_address);
+
+ rsdt = (ACPI_TABLE*)ADD2PTR(rsdp->rsdt_address, KERNEL_VIRT_ADDR);
+ printf(KERNEL_INFO, "RSDT: %p\n", (long)rsdt-KERNEL_VIRT_ADDR);
+
+ num_acpi_tables = (rsdt->length - sizeof(ACPI_TABLE)) / sizeof(void*);
+ acpi_tables = (ACPI_TABLE**)ADD2PTR(rsdt, sizeof(ACPI_TABLE));
+
+ for(int i=0;i<num_acpi_tables;i++) {
+ acpi_process_table((ACPI_TABLE*)ADD2PTR(acpi_tables[i], KERNEL_VIRT_ADDR));
+ }
 }

apic.c

@@ -16,9 +16,11 @@
 #include "setup32.h"
 #include "debug.h"
 
-int lapic_present = 0;
+int lapic_present;
 int lapic_base_register;
 int lapic_id;
+int ioapic_base_register;
+u32 ioapic_gsi_base;
 
 extern int _kernel_pg_dir;
 
@@ -70,6 +72,8 @@ void init_lapic() {
  int eax, edx;
  pte_t *pgtable[1];
 
+ lapic_present = 0;
+
  __asm__ __volatile__("movl $1, %%eax;"
  "cpuid;"
  "andl $0x200, %%edx;"

setup32.c

@@ -90,6 +90,8 @@ int lapic_calibration_tick = 0;
 bool lapic_calibration_mode = false;
 bool lapic_timer_enabled = false;
 
+#define DEBUG_TIMER
+
 #ifdef DEBUG_TIMER
 int timer_counter[MAX_NUM_SMPS];
 int seconds[MAX_NUM_SMPS];
@@ -105,7 +107,7 @@ __attribute__((regparm(0))) void common_interrupt_handler(struct regs_frame *rf)
 
  lapic_calibration_tick++;
 
- } else if (lapic_timer_enabled) {
+ } else {
 #ifdef DEBUG_TIMER
  char s[20];
  timer_counter[CUR_CPU]++;
@@ -117,7 +119,7 @@ __attribute__((regparm(0))) void common_interrupt_handler(struct regs_frame *rf)
  print_vga_fixed(s, 140, 5+CUR_CPU);
  }
 #endif
- }
+ }
  }
 }
 
@@ -284,6 +286,7 @@ void setup32() {
  init_lapic();
 
  if (!lapic_present) {
+ lapic_calibration_tick = 1;
  init_pic_8259();
  init_pit_frequency();
  }

smp.c

@@ -72,8 +72,6 @@ void copy_smp_init_to_low_mem() {
  char *s = (char*)&init_ap;
  char *d = (char*)(AP_INIT_PHYS_TEXT+KERNEL_VIRT_ADDR);
 
- printf(KERNEL_DEBUG, "init_ap_size: %d\n", (int)init_ap_size);
-
  for(int i=0;i<(int)init_ap_size;i++) {
  *d++ = *s++;
  }

system.c

@@ -213,7 +213,7 @@ void bda_read_table() {
 
  short *p = (short*)(0x40e + KERNEL_VIRT_ADDR);
 
- ebda = (int)(unsigned short)*p;
+ ebda = ((int)(unsigned short)*p) << 4;
 
  printf(KERNEL_INFO, "EBDA: %x\n", ebda);
 }

type.h

@@ -22,5 +22,15 @@ typedef char byte;
 
 #define ADD2PTR(x, y) ((long)(x) + (long)(y))
 
-#endif
+typedef unsigned char u8;
+typedef char s8;
+typedef unsigned short u16;
+typedef short s16;
+typedef unsigned int u32;
+typedef int s32;
+typedef long long s64;
+typedef unsigned long long u64;
+
+typedef u32 size_t;
 
+#endif

util.c

@@ -186,3 +186,17 @@ void lltoa(long long val, char *str, int base) {
  str[16] = 0;
 }
 
+int strncmp(const char *s1, const char *s2, size_t len) {
+
+ for(size_t i=0;i<len;i++) {
+
+ if (*s1 < *s2)
+ return -1;
+ else if (*s1 > *s2)
+ return 1;
+
+ s1++; s2++;
+ }
+
+ return 0;
+}

util.h

@@ -23,7 +23,11 @@ typedef unsigned char *va_list;
 #define va_start(arg, list) (list = (unsigned char*)&arg+sizeof(arg))
 #define va_arg(list, type) *((type *) ((list+=sizeof(type))-sizeof(type)))
 
+int strncmp(const char *s1, const char *s2, size_t len);
 int strlen(char *p);
+
+#define memcmp(p1, p2, num) strncmp((const char *)p1, (const char *)p2, num)
+
 void itoa(int val, char *str, int base);
 void ltoa(long val, char *str, int base);
 void lltoa(long long val, char *str, int base);