diff options
Diffstat (limited to 'board/MAI/bios_emulator/bios.c')
-rw-r--r-- | board/MAI/bios_emulator/bios.c | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/board/MAI/bios_emulator/bios.c b/board/MAI/bios_emulator/bios.c new file mode 100644 index 0000000..4707bd9 --- /dev/null +++ b/board/MAI/bios_emulator/bios.c @@ -0,0 +1,335 @@ +/* + * Mostly done after the Scitech Bios emulation + * Written by Hans-Jörg Frieden + * Hyperion Entertainment + */ +#include "x86emu.h" +#include "glue.h" + +#undef DEBUG +#ifdef DEBUG +#define PRINTF(fmt, args...) printf(fmt, ## args) +#else +#define PRINTF(fmt, args...) +#endif + +#define BIOS_SEG 0xFFF0 +#define PCIBIOS_SUCCESSFUL 0 +#define PCIBIOS_DEVICE_NOT_FOUND 0x86 + +typedef unsigned char UBYTE; +typedef unsigned short UWORD; +typedef unsigned long ULONG; + +typedef char BYTE; +typedef short WORT; +typedef long LONG; + +static inline UBYTE read_byte(volatile UBYTE* from) +{ + int x; + asm volatile ("lbz %0,%1\n eieio" : "=r" (x) : "m" (*from)); + return (UBYTE)x; +} + +static inline void write_byte(volatile UBYTE *to, int x) +{ + asm volatile ("stb %1,%0\n eieio" : "=m" (*to) : "r" (x)); +} + +static inline UWORD read_word_little(volatile UWORD *from) +{ + int x; + asm volatile ("lhbrx %0,0,%1\n eieio" : "=r" (x) : "r" (from), "m" (*from)); + return (UWORD)x; +} + +static inline UWORD read_word_big(volatile UWORD *from) +{ + int x; + asm volatile ("lhz %0,%1\n eieio" : "=r" (x) : "m" (*from)); + return (UWORD)x; +} + +static inline void write_word_little(volatile UWORD *to, int x) +{ + asm volatile ("sthbrx %1,0,%2\n eieio" : "=m" (*to) : "r" (x), "r" (to)); +} + +static inline void write_word_big(volatile UWORD *to, int x) +{ + asm volatile ("sth %1,%0\n eieio" : "=m" (*to) : "r" (x)); +} + +static inline ULONG read_long_little(volatile ULONG *from) +{ + unsigned long x; + asm volatile ("lwbrx %0,0,%1\n eieio" : "=r" (x) : "r" (from), "m"(*from)); + return (ULONG)x; +} + +static inline ULONG read_long_big(volatile ULONG *from) +{ + unsigned long x; + asm volatile ("lwz %0,%1\n eieio" : "=r" (x) : "m" (*from)); + return (ULONG)x; +} + +static inline void write_long_little(volatile ULONG *to, ULONG x) +{ + asm volatile ("stwbrx %1,0,%2\n eieio" : "=m" (*to) : "r" (x), "r" (to)); +} + +static inline void write_long_big(volatile ULONG *to, ULONG x) +{ + asm volatile ("stw %1,%0\n eieio" : "=m" (*to) : "r" (x)); +} + +#define port_to_mem(from) (0xFE000000|(from)) +#define in_byte(from) read_byte( (UBYTE *)port_to_mem(from)) +#define in_word(from) read_word_little((UWORD *)port_to_mem(from)) +#define in_long(from) read_long_little((ULONG *)port_to_mem(from)) +#define out_byte(to, val) write_byte((UBYTE *)port_to_mem(to), val) +#define out_word(to, val) write_word_little((UWORD *)port_to_mem(to), val) +#define out_long(to, val) write_long_little((ULONG *)port_to_mem(to), val) + +static void X86API undefined_intr(int intno) +{ + extern u16 A1_rdw(u32 addr); + if (A1_rdw(intno * 4 + 2) == BIOS_SEG) + { + PRINTF("Undefined interrupt %xh called AX = %xh, BX = %xh, CX = %xh, DX = %xh\n", + intno, M.x86.R_AX, M.x86.R_BX, M.x86.R_CX, M.x86.R_DX); + X86EMU_halt_sys(); + } + else + { + PRINTF("Calling interrupt %xh, AL=%xh, AH=%xh\n", intno, M.x86.R_AL, M.x86.R_AH); + X86EMU_prepareForInt(intno); + } +} + +static void X86API int42(int intno); +static void X86API int15(int intno); + +static void X86API int10(int intno) +{ + if (A1_rdw(intno*4+2) == BIOS_SEG) + int42(intno); + else + { + PRINTF("int10: branching to %04X:%04X, AL=%xh, AH=%xh\n", A1_rdw(intno*4+2), A1_rdw(intno*4), + M.x86.R_AL, M.x86.R_AH); + X86EMU_prepareForInt(intno); + } +} + +static void X86API int1A(int intno) +{ + int device; + + switch(M.x86.R_AX) + { + case 0xB101: // PCI Bios Present? + M.x86.R_AL = 0x00; + M.x86.R_EDX = 0x20494350; + M.x86.R_BX = 0x0210; + M.x86.R_CL = 3; + CLEAR_FLAG(F_CF); + break; + case 0xB102: // Find device + device = mypci_find_device(M.x86.R_DX, M.x86.R_CX, M.x86.R_SI); + if (device != -1) + { + M.x86.R_AH = PCIBIOS_SUCCESSFUL; + M.x86.R_BH = mypci_bus(device); + M.x86.R_BL = mypci_devfn(device); + } + else + { + M.x86.R_AH = PCIBIOS_DEVICE_NOT_FOUND; + } + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + break; + case 0xB103: // Find PCI class code + M.x86.R_AH = PCIBIOS_DEVICE_NOT_FOUND; + //printf("Find by class not yet implmented"); + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + break; + case 0xB108: // read config byte + M.x86.R_CL = mypci_read_cfg_byte(M.x86.R_BH, M.x86.R_BL, M.x86.R_DI); + M.x86.R_AH = PCIBIOS_SUCCESSFUL; + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + //printf("read_config_byte %x,%x,%x -> %x\n", M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, + // M.x86.R_CL); + break; + case 0xB109: // read config word + M.x86.R_CX = mypci_read_cfg_word(M.x86.R_BH, M.x86.R_BL, M.x86.R_DI); + M.x86.R_AH = PCIBIOS_SUCCESSFUL; + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + //printf("read_config_word %x,%x,%x -> %x\n", M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, + // M.x86.R_CX); + break; + case 0xB10A: // read config dword + M.x86.R_ECX = mypci_read_cfg_long(M.x86.R_BH, M.x86.R_BL, M.x86.R_DI); + M.x86.R_AH = PCIBIOS_SUCCESSFUL; + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + //printf("read_config_long %x,%x,%x -> %x\n", M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, + // M.x86.R_ECX); + break; + case 0xB10B: // write config byte + mypci_write_cfg_byte(M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, M.x86.R_CL); + M.x86.R_AH = PCIBIOS_SUCCESSFUL; + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + //printf("write_config_byte %x,%x,%x <- %x\n", M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, + // M.x86.R_CL); + break; + case 0xB10C: // write config word + mypci_write_cfg_word(M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, M.x86.R_CX); + M.x86.R_AH = PCIBIOS_SUCCESSFUL; + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + //printf("write_config_word %x,%x,%x <- %x\n", M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, + // M.x86.R_CX); + break; + case 0xB10D: // write config dword + mypci_write_cfg_long(M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, M.x86.R_ECX); + M.x86.R_AH = PCIBIOS_SUCCESSFUL; + CONDITIONAL_SET_FLAG((M.x86.R_AH != PCIBIOS_SUCCESSFUL), F_CF); + //printf("write_config_long %x,%x,%x <- %x\n", M.x86.R_BH, M.x86.R_BL, M.x86.R_DI, + // M.x86.R_ECX); + break; + default: + PRINTF("BIOS int %xh: Unknown function AX=%04xh\n", intno, M.x86.R_AX); + + } +} + +void bios_init(void) +{ + int i; + X86EMU_intrFuncs bios_intr_tab[256]; + + for (i=0; i<256; i++) + { + write_long_little(M.mem_base+i*4, BIOS_SEG<<16); + bios_intr_tab[i] = undefined_intr; + } + + bios_intr_tab[0x10] = int10; + bios_intr_tab[0x1A] = int1A; + bios_intr_tab[0x42] = int42; + bios_intr_tab[0x15] = int15; + + bios_intr_tab[0x6D] = int42; + + X86EMU_setupIntrFuncs(bios_intr_tab); + video_init(); +} + +unsigned char setup_40x25[] = +{ + 0x38, 0x28, 0x2d, 0x0a, 0x1f, 6, 0x19, + 0x1c, 2, 7, 6, 7, 0, 0, 0, 0 +}; + +unsigned char setup_80x25[] = +{ + 0x71, 0x50, 0x5a, 0x0a, 0x1f, 6, 0x19, + 0x1c, 2, 7, 6, 7, 0, 0, 0, 0 +}; + +unsigned char setup_graphics[] = +{ + 0x38, 0x28, 0x20, 0x0a, 0x7f, 6, 0x64, + 0x70, 2, 1, 6, 7, 0, 0, 0, 0 +}; + +unsigned char setup_bw[] = +{ + 0x61, 0x50, 0x52, 0x0f, 0x19, 6, 0x19, + 0x19, 2, 0x0d, 0x0b, 0x0c, 0, 0, 0, 0 +}; + +unsigned char * setup_modes[] = +{ + setup_40x25, // mode 0: 40x25 bw text + setup_40x25, // mode 1: 40x25 col text + setup_80x25, // mode 2: 80x25 bw text + setup_80x25, // mode 3: 80x25 col text + setup_graphics, // mode 4: 320x200 col graphics + setup_graphics, // mode 5: 320x200 bw graphics + setup_graphics, // mode 6: 640x200 bw graphics + setup_bw // mode 7: 80x25 mono text +}; + +unsigned int setup_cols[] = +{ + 40, 40, 80, 80, 40, 40, 80, 80 +}; + +unsigned char setup_modesets[] = +{ + 0x2C, 0x28, 0x2D, 0x29, 0x2A, 0x2E, 0x1E, 0x29 +}; + +unsigned int setup_bufsize[] = +{ + 2048, 2048, 4096, 2096, 16384, 16384, 16384, 4096 +}; + +void bios_set_mode(int mode) +{ + int i; + unsigned char mode_set = setup_modesets[mode]; // Control register value + unsigned char *setup_regs = setup_modes[mode]; // Register 3D4 Array + + // Switch video off + out_byte(0x3D8, mode_set & 0x37); + + // Set up parameters at 3D4h + for (i=0; i<16; i++) + { + out_byte(0x3D4, (unsigned char)i); + out_byte(0x3D5, *setup_regs); + setup_regs++; + } + + // Enable video + out_byte(0x3D8, mode_set); + + // Set overscan + if (mode == 6) out_byte(0x3D9, 0x3F); + else out_byte(0x3D9, 0x30); +} + +static void bios_print_string(void) +{ + extern void video_bios_print_string(char *string, int x, int y, int attr, int count); + char *s = (char *)(M.x86.R_ES<<4) + M.x86.R_BP; + int attr; + if (M.x86.R_AL & 0x02) attr = - 1; + else attr = M.x86.R_BL; + video_bios_print_string(s, M.x86.R_DH, M.x86.R_DL, attr, M.x86.R_CX); +} + +static void X86API int42(int intno) +{ + switch (M.x86.R_AH) + { + case 0x00: + bios_set_mode(M.x86.R_AL); + break; + case 0x13: + bios_print_string(); + break; + default: + PRINTF("Warning: VIDEO BIOS interrupt %xh unimplemented function %xh, AL = %xh\n", + intno, M.x86.R_AH, M.x86.R_AL); + } +} + +static void X86API int15(int intno) +{ + PRINTF("Called interrupt 15h: AX = %xh, BX = %xh, CX = %xh, DX = %xh\n", + M.x86.R_AX, M.x86.R_BX, M.x86.R_CX, M.x86.R_DX); +} |