[mirror_edk2.git] / OvmfPkg / Library / LoadLinuxLib / LinuxGdt.c

/** @file\r
  Initialize GDT for Linux.\r
\r
  Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "LoadLinuxLib.h"\r
\r
//\r
// Local structure definitions\r
//\r
\r
#pragma pack (1)\r
\r
//\r
// Global Descriptor Entry structures\r
//\r
\r
typedef struct _GDT_ENTRY {\r
  UINT16    Limit15_0;\r
  UINT16    Base15_0;\r
  UINT8     Base23_16;\r
  UINT8     Type;\r
  UINT8     Limit19_16_and_flags;\r
  UINT8     Base31_24;\r
} GDT_ENTRY;\r
\r
typedef\r
  struct _GDT_ENTRIES {\r
  GDT_ENTRY    Null;\r
  GDT_ENTRY    Null2;\r
  GDT_ENTRY    Linear;\r
  GDT_ENTRY    LinearCode;\r
  GDT_ENTRY    TaskSegment;\r
  GDT_ENTRY    Spare4;\r
  GDT_ENTRY    Spare5;\r
} GDT_ENTRIES;\r
\r
#pragma pack ()\r
\r
STATIC GDT_ENTRIES  *mGdt = NULL;\r
\r
//\r
// Global descriptor table (GDT) Template\r
//\r
STATIC GDT_ENTRIES  GdtTemplate = {\r
  //\r
  // Null\r
  //\r
  {\r
    0x0,            // limit 15:0\r
    0x0,            // base 15:0\r
    0x0,            // base 23:16\r
    0x0,            // type\r
    0x0,            // limit 19:16, flags\r
    0x0,            // base 31:24\r
  },\r
  //\r
  // Null2\r
  //\r
  {\r
    0x0,            // limit 15:0\r
    0x0,            // base 15:0\r
    0x0,            // base 23:16\r
    0x0,            // type\r
    0x0,            // limit 19:16, flags\r
    0x0,            // base 31:24\r
  },\r
  //\r
  // Linear\r
  //\r
  {\r
    0x0FFFF,        // limit 0xFFFFF\r
    0x0,            // base 0\r
    0x0,\r
    0x09A,          // present, ring 0, data, expand-up, writable\r
    0x0CF,          // page-granular, 32-bit\r
    0x0,\r
  },\r
  //\r
  // LinearCode\r
  //\r
  {\r
    0x0FFFF,        // limit 0xFFFFF\r
    0x0,            // base 0\r
    0x0,\r
    0x092,          // present, ring 0, data, expand-up, writable\r
    0x0CF,          // page-granular, 32-bit\r
    0x0,\r
  },\r
  //\r
  // TaskSegment\r
  //\r
  {\r
    0x0,            // limit 0\r
    0x0,            // base 0\r
    0x0,\r
    0x089,          // ?\r
    0x080,          // ?\r
    0x0,\r
  },\r
  //\r
  // Spare4\r
  //\r
  {\r
    0x0,            // limit 0\r
    0x0,            // base 0\r
    0x0,\r
    0x0,            // present, ring 0, data, expand-up, writable\r
    0x0,            // page-granular, 32-bit\r
    0x0,\r
  },\r
  //\r
  // Spare5\r
  //\r
  {\r
    0x0,            // limit 0\r
    0x0,            // base 0\r
    0x0,\r
    0x0,            // present, ring 0, data, expand-up, writable\r
    0x0,            // page-granular, 32-bit\r
    0x0,\r
  },\r
};\r
\r
/**\r
  Initialize Global Descriptor Table.\r
\r
**/\r
VOID\r
InitLinuxDescriptorTables (\r
  VOID\r
  )\r
{\r
  //\r
  // Allocate Runtime Data for the GDT\r
  //\r
  mGdt = AllocateRuntimePool (sizeof (GdtTemplate) + 8);\r
  ASSERT (mGdt != NULL);\r
  mGdt = ALIGN_POINTER (mGdt, 8);\r
\r
  //\r
  // Initialize all GDT entries\r
  //\r
  CopyMem (mGdt, &GdtTemplate, sizeof (GdtTemplate));\r
}\r
\r
/**\r
  Initialize Global Descriptor Table.\r
\r
**/\r
VOID\r
SetLinuxDescriptorTables (\r
  VOID\r
  )\r
{\r
  IA32_DESCRIPTOR  GdtPtr;\r
  IA32_DESCRIPTOR  IdtPtr;\r
\r
  //\r
  // Write GDT register\r
  //\r
  GdtPtr.Base  = (UINT32)(UINTN)(VOID *)mGdt;\r
  GdtPtr.Limit = (UINT16)(sizeof (GdtTemplate) - 1);\r
  AsmWriteGdtr (&GdtPtr);\r
\r
  IdtPtr.Base  = (UINT32)0;\r
  IdtPtr.Limit = (UINT16)0;\r
  AsmWriteIdtr (&IdtPtr);\r
}\r
Commit	Line	Data
3c0a051f	1	/** @file\r
	2	Initialize GDT for Linux.\r
	3	\r
	4	Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>\r
b26f0cf9	5	SPDX-License-Identifier: BSD-2-Clause-Patent\r
3c0a051f	6	\r
	7	**/\r
	8	\r
	9	#include "LoadLinuxLib.h"\r
	10	\r
3c0a051f	11	//\r
	12	// Local structure definitions\r
	13	//\r
	14	\r
	15	#pragma pack (1)\r
	16	\r
	17	//\r
	18	// Global Descriptor Entry structures\r
	19	//\r
	20	\r
	21	typedef struct _GDT_ENTRY {\r
ac0a286f MK	22	UINT16 Limit15_0;\r
	23	UINT16 Base15_0;\r
	24	UINT8 Base23_16;\r
	25	UINT8 Type;\r
	26	UINT8 Limit19_16_and_flags;\r
	27	UINT8 Base31_24;\r
3c0a051f	28	} GDT_ENTRY;\r
	29	\r
	30	typedef\r
ac0a286f MK	31	struct _GDT_ENTRIES {\r
	32	GDT_ENTRY Null;\r
	33	GDT_ENTRY Null2;\r
	34	GDT_ENTRY Linear;\r
	35	GDT_ENTRY LinearCode;\r
	36	GDT_ENTRY TaskSegment;\r
	37	GDT_ENTRY Spare4;\r
	38	GDT_ENTRY Spare5;\r
3c0a051f	39	} GDT_ENTRIES;\r
	40	\r
	41	#pragma pack ()\r
	42	\r
ac0a286f	43	STATIC GDT_ENTRIES *mGdt = NULL;\r
3c0a051f	44	\r
	45	//\r
	46	// Global descriptor table (GDT) Template\r
	47	//\r
ac0a286f	48	STATIC GDT_ENTRIES GdtTemplate = {\r
3c0a051f	49	//\r
	50	// Null\r
	51	//\r
	52	{\r
	53	0x0, // limit 15:0\r
	54	0x0, // base 15:0\r
	55	0x0, // base 23:16\r
	56	0x0, // type\r
	57	0x0, // limit 19:16, flags\r
	58	0x0, // base 31:24\r
	59	},\r
	60	//\r
	61	// Null2\r
	62	//\r
	63	{\r
	64	0x0, // limit 15:0\r
	65	0x0, // base 15:0\r
	66	0x0, // base 23:16\r
	67	0x0, // type\r
	68	0x0, // limit 19:16, flags\r
	69	0x0, // base 31:24\r
	70	},\r
	71	//\r
	72	// Linear\r
	73	//\r
	74	{\r
	75	0x0FFFF, // limit 0xFFFFF\r
	76	0x0, // base 0\r
	77	0x0,\r
	78	0x09A, // present, ring 0, data, expand-up, writable\r
	79	0x0CF, // page-granular, 32-bit\r
	80	0x0,\r
	81	},\r
	82	//\r
	83	// LinearCode\r
	84	//\r
	85	{\r
	86	0x0FFFF, // limit 0xFFFFF\r
	87	0x0, // base 0\r
	88	0x0,\r
	89	0x092, // present, ring 0, data, expand-up, writable\r
	90	0x0CF, // page-granular, 32-bit\r
	91	0x0,\r
	92	},\r
	93	//\r
	94	// TaskSegment\r
	95	//\r
	96	{\r
	97	0x0, // limit 0\r
	98	0x0, // base 0\r
	99	0x0,\r
	100	0x089, // ?\r
	101	0x080, // ?\r
	102	0x0,\r
	103	},\r
	104	//\r
	105	// Spare4\r
	106	//\r
	107	{\r
	108	0x0, // limit 0\r
	109	0x0, // base 0\r
	110	0x0,\r
	111	0x0, // present, ring 0, data, expand-up, writable\r
	112	0x0, // page-granular, 32-bit\r
113	0x0,\r
114	},\r
115	//\r
116	// Spare5\r
117	//\r
118	{\r
119	0x0, // limit 0\r
120	0x0, // base 0\r
121	0x0,\r
122	0x0, // present, ring 0, data, expand-up, writable\r
123	0x0, // page-granular, 32-bit\r
124	0x0,\r
125	},\r
126	};\r
127	\r
128	/**\r
129	Initialize Global Descriptor Table.\r
130	\r
131	**/\r
132	VOID\r
133	InitLinuxDescriptorTables (\r
134	VOID\r
135	)\r
136	{\r
137	//\r
138	// Allocate Runtime Data for the GDT\r
139	//\r
140	mGdt = AllocateRuntimePool (sizeof (GdtTemplate) + 8);\r
141	ASSERT (mGdt != NULL);\r
142	mGdt = ALIGN_POINTER (mGdt, 8);\r
143	\r
144	//\r
145	// Initialize all GDT entries\r
146	//\r
147	CopyMem (mGdt, &GdtTemplate, sizeof (GdtTemplate));\r
3c0a051f	148	}\r
	149	\r
	150	/**\r
	151	Initialize Global Descriptor Table.\r
	152	\r
	153	**/\r
	154	VOID\r
	155	SetLinuxDescriptorTables (\r
	156	VOID\r
	157	)\r
	158	{\r
ac0a286f MK	159	IA32_DESCRIPTOR GdtPtr;\r
ac0a286f MK	160	IA32_DESCRIPTOR IdtPtr;\r
3c0a051f	161	\r
	162	//\r
	163	// Write GDT register\r
	164	//\r
ac0a286f MK	165	GdtPtr.Base = (UINT32)(UINTN)(VOID *)mGdt;\r
ac0a286f MK	166	GdtPtr.Limit = (UINT16)(sizeof (GdtTemplate) - 1);\r
3c0a051f	167	AsmWriteGdtr (&GdtPtr);\r
3c0a051f	168	\r
ac0a286f MK	169	IdtPtr.Base = (UINT32)0;\r
ac0a286f MK	170	IdtPtr.Limit = (UINT16)0;\r
3c0a051f	171	AsmWriteIdtr (&IdtPtr);\r
3c0a051f	172	}\r