Vystem 0.2

shelter/lib/include/irq/gdt.h

@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: MPL-2.0
+#ifndef SH_LIB_GDT_H
+#define SH_LIB_GDT_H
+#include "std/status.h"
+#include "std/type.h"
+#include "irq/tss.h"
+// Long mode GDT part
+// GDT entry 64 bits structure
+#pragma pack(1)
+typedef struct {
+  sh_uint16 limit_low;
+  sh_uint16 base_low;
+  sh_uint8 base_mid;
+  sh_uint8 access;
+  sh_uint8 flags_limit_high;
+  sh_uint8 base_high;
+} sh_gdt_GDT_ENTRY_64;
+#pragma pack()
+// GDT entry 128 bits (special TSS) structure
+#pragma pack(1)
+typedef struct {
+  sh_uint16 limit_low;
+  sh_uint16 base_low;
+  sh_uint8 base_mid;
+  sh_uint8 access;
+  sh_uint8 flags_limit_high;
+  sh_uint8 base_high;
+  sh_uint32 base_upper;
+  sh_uint32 reserved;
+} sh_gdt_GDT_ENTRY_128;
+#pragma pack()
+// GDTR structure
+#pragma pack(1)
+typedef struct {
+  sh_uint16 limit;
+  sh_uint64 base;
+} sh_gdt_GDTR;
+#pragma pack()
+// GDT structure for bootstrap core
+#pragma pack(1)
+typedef struct {
+  sh_gdt_GDT_ENTRY_64 null;
+  sh_gdt_GDT_ENTRY_64 kernel_code;
+  sh_gdt_GDT_ENTRY_64 kernel_data;
+  sh_gdt_GDT_ENTRY_64 user_code;
+  sh_gdt_GDT_ENTRY_64 user_data;
+  sh_gdt_GDT_ENTRY_128 tss;
+} sh_gdt_GDT;
+#pragma pack()
+// GDT structure for all APs
+#pragma pack(1)
+typedef struct {
+  sh_gdt_GDT_ENTRY_64 null;
+  sh_gdt_GDT_ENTRY_64 kernel_code;
+  sh_gdt_GDT_ENTRY_64 kernel_data;
+  sh_gdt_GDT_ENTRY_64 user_code;
+  sh_gdt_GDT_ENTRY_64 user_data;
+  sh_gdt_GDT_ENTRY_128 tss[256];
+} sh_gdt_GDT_AP;
+#pragma pack()
+// Generate access byte
+inline sh_uint8 sh_gdt_fill_access_byte(sh_bool present,sh_uint8 dpl,sh_bool descriptor_type,sh_uint8 segment_type) {
+  return ((present?1:0)<<7)|((dpl&0x3)<<5)|((descriptor_type?1:0)<<4)|(segment_type&0xF);
+}
+// Generate flags byte (put all 4 bits in bit 0-3 of the returned byte)
+inline sh_uint8 sh_gdt_fill_flags_byte(sh_bool g,sh_bool db,sh_bool l,sh_bool avl) {
+  return ((g?1:0)<<3)|((db?1:0)<<2)|((l?1:0)<<1)|((avl?1:0)<<0);
+}
+// Fill GDT entry 64 bits, expect flags as sh_gdt_fill_flags_byte would return it
+sh_gdt_GDT_ENTRY_64 sh_gdt_fill_gdt_entry_64(sh_uint32 limit,sh_uint32 base,sh_uint8 access,sh_uint8 flags);
+// Fill GDT entry 128 bits, expect flags as sh_gdt_fill_flags_byte would return it
+sh_gdt_GDT_ENTRY_128 sh_gdt_fill_gdt_entry_128(sh_uint32 limit,sh_uint64 base,sh_uint8 access,sh_uint8 flags);
+// Fill GDT with provided TSS
+SH_STATUS sh_gdt_fill_gdt(sh_tss_TSS *tss,sh_gdt_GDT *gdt);
+// Fill APs common GDT with provided TSS array
+SH_STATUS sh_gdt_fill_gdt_ap(sh_tss_TSS *tss,sh_uint64 tss_count,sh_gdt_GDT_AP *gdt);
+// Generate GDTR for AP GDT
+sh_gdt_GDTR sh_gdt_make_gdtr_ap(sh_gdt_GDT_AP *gdt);
+// Fill and load GDTR
+SH_STATUS sh_gdt_load_gdtr(sh_gdt_GDT *gdt);
+// Reload registers
+SH_STATUS sh_gdt_reload_registers();
+// 16/32 bits mode GDT part
+// GDT entry 32 bits structure
+#pragma pack(1)
+typedef struct {
+  sh_uint16 limit_low;
+  sh_uint16 base_low;
+  sh_uint8 base_middle;
+  sh_uint8 access;
+  sh_uint8 granularity;
+  sh_uint8 base_high;
+} sh_gdt_GDT_ENTRY_32;
+#pragma pack()
+// GDT 32 bits structure
+#pragma pack(1)
+typedef struct {
+  sh_gdt_GDT_ENTRY_32 null;
+  sh_gdt_GDT_ENTRY_32 code_64;
+  sh_gdt_GDT_ENTRY_32 code;
+  sh_gdt_GDT_ENTRY_32 data;
+} sh_gdt_GDT_32;
+#pragma pack()
+// Generate access byte
+inline sh_uint8 sh_gdt_fill_access_byte_32(sh_bool present,sh_uint8 dpl,sh_bool descriptor_type,sh_uint8 segment_type) {
+  sh_uint8 access=0;
+  access|=(present?1:0)<<7;
+  access|=(dpl&0x3)<<5;
+  access|=(descriptor_type?1:0)<<4;
+  access|=(segment_type&0xF);
+  return access;
+}
+// Generate granularity byte
+inline sh_uint8 sh_gdt_fill_granularity_byte_32(sh_bool granularity,sh_bool db,sh_bool l,sh_bool avl) {
+  sh_uint8 g=0;
+  g|=(granularity?1:0)<<7;
+  g|=(db?1:0)<<6;
+  g|=(l?1:0)<<5;
+  g|=(avl?1:0)<<4;
+  return g;
+}
+// Fill GDT entry 32 bits, expect granularity as sh_gdt_fill_granularity_byte_32 would return it
+sh_gdt_GDT_ENTRY_32 sh_gdt_fill_gdt_entry_32(sh_uint32 limit,sh_uint32 base,sh_uint8 access,sh_uint8 granularity);
+// Fill GDT 32 bits
+SH_STATUS sh_gdt_fill_gdt_32(sh_gdt_GDT_32 *gdt_32);
+#endif