--- /dev/null
+// Variable layouts of bios.
+//
+// Copyright (C) 2008-2010 Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+#ifndef __BIOSVAR_H
+#define __BIOSVAR_H
+
+#include "types.h" // u8
+#include "farptr.h" // GET_FARVAR
+#include "config.h" // CONFIG_*
+#include "disk.h" // struct chs_s
+
+
+/****************************************************************
+ * Interupt vector table
+ ****************************************************************/
+
+struct rmode_IVT {
+ struct segoff_s ivec[256];
+};
+
+#define GET_IVT(vector) \
+ GET_FARVAR(SEG_IVT, ((struct rmode_IVT *)0)->ivec[vector])
+#define SET_IVT(vector, segoff) \
+ SET_FARVAR(SEG_IVT, ((struct rmode_IVT *)0)->ivec[vector], segoff)
+
+#define FUNC16(func) ({ \
+ ASSERT32FLAT(); \
+ extern void func (void); \
+ SEGOFF(SEG_BIOS, (u32)func - BUILD_BIOS_ADDR); \
+ })
+
+
+/****************************************************************
+ * Bios Data Area (BDA)
+ ****************************************************************/
+
+struct bios_data_area_s {
+ // 40:00
+ u16 port_com[4];
+ u16 port_lpt[3];
+ u16 ebda_seg;
+ // 40:10
+ u16 equipment_list_flags;
+ u8 pad1;
+ u16 mem_size_kb;
+ u8 pad2;
+ u8 ps2_ctrl_flag;
+ u8 kbd_flag0;
+ u8 kbd_flag1;
+ u8 alt_keypad;
+ u16 kbd_buf_head;
+ u16 kbd_buf_tail;
+ // 40:1e
+ u8 kbd_buf[32];
+ u8 floppy_recalibration_status;
+ u8 floppy_motor_status;
+ // 40:40
+ u8 floppy_motor_counter;
+ u8 floppy_last_status;
+ u8 floppy_return_status[7];
+ u8 video_mode;
+ u16 video_cols;
+ u16 video_pagesize;
+ u16 video_pagestart;
+ // 40:50
+ u16 cursor_pos[8];
+ // 40:60
+ u16 cursor_type;
+ u8 video_page;
+ u16 crtc_address;
+ u8 video_msr;
+ u8 video_pal;
+ struct segoff_s jump;
+ u8 other_6b;
+ u32 timer_counter;
+ // 40:70
+ u8 timer_rollover;
+ u8 break_flag;
+ u16 soft_reset_flag;
+ u8 disk_last_status;
+ u8 hdcount;
+ u8 disk_control_byte;
+ u8 port_disk;
+ u8 lpt_timeout[4];
+ u8 com_timeout[4];
+ // 40:80
+ u16 kbd_buf_start_offset;
+ u16 kbd_buf_end_offset;
+ u8 video_rows;
+ u16 char_height;
+ u8 video_ctl;
+ u8 video_switches;
+ u8 modeset_ctl;
+ u8 dcc_index;
+ u8 floppy_last_data_rate;
+ u8 disk_status_controller;
+ u8 disk_error_controller;
+ u8 disk_interrupt_flag;
+ u8 floppy_harddisk_info;
+ // 40:90
+ u8 floppy_media_state[4];
+ u8 floppy_track[2];
+ u8 kbd_flag2;
+ u8 kbd_led;
+ struct segoff_s user_wait_complete_flag;
+ u32 user_wait_timeout;
+ // 40:A0
+ u8 rtc_wait_flag;
+ u8 other_a1[7];
+ struct segoff_s video_savetable;
+ u8 other_ac[4];
+ // 40:B0
+ u8 other_b0[10];
+ u16 vbe_mode;
+} PACKED;
+
+// BDA floppy_recalibration_status bitdefs
+#define FRS_TIMEOUT (1<<7)
+
+// BDA rtc_wait_flag bitdefs
+#define RWS_WAIT_PENDING (1<<0)
+#define RWS_WAIT_ELAPSED (1<<7)
+
+// BDA floppy_media_state bitdefs
+#define FMS_DRIVE_STATE_MASK (0x07)
+#define FMS_MEDIA_DRIVE_ESTABLISHED (1<<4)
+#define FMS_DOUBLE_STEPPING (1<<5)
+#define FMS_DATA_RATE_MASK (0xc0)
+
+// Accessor functions
+#define GET_BDA(var) \
+ GET_FARVAR(SEG_BDA, ((struct bios_data_area_s *)0)->var)
+#define SET_BDA(var, val) \
+ SET_FARVAR(SEG_BDA, ((struct bios_data_area_s *)0)->var, (val))
+#define CLEARBITS_BDA(var, val) do { \
+ typeof(((struct bios_data_area_s *)0)->var) __val = GET_BDA(var); \
+ SET_BDA(var, (__val & ~(val))); \
+ } while (0)
+#define SETBITS_BDA(var, val) do { \
+ typeof(((struct bios_data_area_s *)0)->var) __val = GET_BDA(var); \
+ SET_BDA(var, (__val | (val))); \
+ } while (0)
+
+
+/****************************************************************
+ * Extended Bios Data Area (EBDA)
+ ****************************************************************/
+
+// DPTE definition
+struct dpte_s {
+ u16 iobase1;
+ u16 iobase2;
+ u8 prefix;
+ u8 unused;
+ u8 irq;
+ u8 blkcount;
+ u8 dma;
+ u8 pio;
+ u16 options;
+ u16 reserved;
+ u8 revision;
+ u8 checksum;
+};
+
+// ElTorito Device Emulation data
+struct cdemu_s {
+ struct drive_s *emulated_drive_gf;
+ u32 ilba;
+ u16 buffer_segment;
+ u16 load_segment;
+ u16 sector_count;
+ u8 active;
+ u8 media;
+ u8 emulated_extdrive;
+
+ // Virtual device
+ struct chs_s lchs;
+};
+
+struct fdpt_s {
+ u16 cylinders;
+ u8 heads;
+ u8 a0h_signature;
+ u8 phys_sectors;
+ u16 precompensation;
+ u8 reserved;
+ u8 drive_control_byte;
+ u16 phys_cylinders;
+ u8 phys_heads;
+ u16 landing_zone;
+ u8 sectors;
+ u8 checksum;
+} PACKED;
+
+struct usbkeyinfo {
+ union {
+ struct {
+ u8 modifiers;
+ u8 repeatcount;
+ u8 keys[6];
+ };
+ u64 data;
+ };
+};
+
+struct extended_bios_data_area_s {
+ u8 size;
+ u8 reserved1[0x21];
+ struct segoff_s far_call_pointer;
+ u8 mouse_flag1;
+ u8 mouse_flag2;
+ u8 mouse_data[0x08];
+ // 0x30
+ u8 other1[0x0d];
+
+ // 0x3d
+ struct fdpt_s fdpt[2];
+
+ // 0x5d
+ u8 other2[0xC4];
+
+ // 0x121 - Begin custom storage.
+ u8 ps2ctr;
+ struct usbkeyinfo usbkey_last;
+
+ int RTCusers;
+
+ // El Torito Emulation data
+ struct cdemu_s cdemu;
+
+ // Buffer for disk DPTE table
+ struct dpte_s dpte;
+
+ // Locks for removable devices
+ u8 cdrom_locks[CONFIG_MAX_EXTDRIVE];
+
+ u16 boot_sequence;
+
+ // Stack space available for code that needs it.
+ u8 extra_stack[512] __aligned(8);
+} PACKED;
+
+// The initial size and location of EBDA
+#define EBDA_SIZE_START \
+ DIV_ROUND_UP(sizeof(struct extended_bios_data_area_s), 1024)
+#define EBDA_SEGMENT_START \
+ FLATPTR_TO_SEG(BUILD_LOWRAM_END - EBDA_SIZE_START*1024)
+
+// Accessor functions
+static inline u16 get_ebda_seg(void) {
+ return GET_BDA(ebda_seg);
+}
+static inline struct extended_bios_data_area_s *
+get_ebda_ptr(void)
+{
+ ASSERT32FLAT();
+ return MAKE_FLATPTR(get_ebda_seg(), 0);
+}
+#define GET_EBDA2(eseg, var) \
+ GET_FARVAR(eseg, ((struct extended_bios_data_area_s *)0)->var)
+#define SET_EBDA2(eseg, var, val) \
+ SET_FARVAR(eseg, ((struct extended_bios_data_area_s *)0)->var, (val))
+#define GET_EBDA(var) \
+ GET_EBDA2(get_ebda_seg(), var)
+#define SET_EBDA(var, val) \
+ SET_EBDA2(get_ebda_seg(), var, (val))
+
+#define EBDA_OFFSET_TOP_STACK \
+ offsetof(struct extended_bios_data_area_s, extra_stack[ \
+ FIELD_SIZEOF(struct extended_bios_data_area_s \
+ , extra_stack)])
+
+
+/****************************************************************
+ * Global variables
+ ****************************************************************/
+
+#if MODE16 == 0 && MODESEGMENT == 1
+// In 32bit segmented mode %cs may not be readable and the code may be
+// relocated. The entry code sets up %gs with a readable segment and
+// the code offset can be determined by get_global_offset().
+#define GLOBAL_SEGREG GS
+static inline u32 __attribute_const get_global_offset(void) {
+ u32 ret;
+ asm(" calll 1f\n"
+ "1:popl %0\n"
+ " subl $1b, %0"
+ : "=r"(ret));
+ return ret;
+}
+#else
+#define GLOBAL_SEGREG CS
+static inline u32 __attribute_const get_global_offset(void) {
+ return 0;
+}
+#endif
+static inline u16 get_global_seg(void) {
+ return GET_SEG(GLOBAL_SEGREG);
+}
+#define GET_GLOBAL(var) \
+ GET_VAR(GLOBAL_SEGREG, *(typeof(&(var)))((void*)&(var) \
+ + get_global_offset()))
+#define SET_GLOBAL(var, val) do { \
+ ASSERT32FLAT(); \
+ (var) = (val); \
+ } while (0)
+#if MODESEGMENT
+#define GLOBALFLAT2GLOBAL(var) ((typeof(var))((void*)(var) - BUILD_BIOS_ADDR))
+#else
+#define GLOBALFLAT2GLOBAL(var) (var)
+#endif
+// Access a "flat" pointer known to point to the f-segment.
+#define GET_GLOBALFLAT(var) GET_GLOBAL(*GLOBALFLAT2GLOBAL(&(var)))
+
+
+/****************************************************************
+ * Bios Config Table
+ ****************************************************************/
+
+struct bios_config_table_s {
+ u16 size;
+ u8 model;
+ u8 submodel;
+ u8 biosrev;
+ u8 feature1, feature2, feature3, feature4, feature5;
+} PACKED;
+
+extern struct bios_config_table_s BIOS_CONFIG_TABLE __aligned(1);
+
+#endif // __BIOSVAR_H
