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-rw-r--r--board/MAI/bios_emulator/bios.c335
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 0000000000..4707bd9a8c
--- /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);
+}
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