ia16-elf-gcc: introduce DOSTEXT and DOSDATA macros.

Using DOSTEXT(x) accesses x in LGROUP and DOSDATA(x) in DGROUP.
This is necessary since ia16-elf-gcc does not understand data
in far segments.

For non-macro'ed symbols, FP_SEG needs to be replaced by explicit
segment references.

kernel/init-dat.h

@@ -1,5 +1,7 @@
 #undef DOSFAR
 #undef DOSTEXTFAR
+#define DOSDATA(x) (x)
+#define DOSTEXT(x) (x)
 
 /* Included by initialisation functions */
 
@@ -23,7 +25,18 @@ extern __segment DosTextSeg;
 #define DOSFAR FAR
 #define DOSTEXTFAR FAR
 
-#elif !defined(I86) || defined(__GNUC__)
+#elif defined(__GNUC__)
+
+#define DosTextSeg 0x70
+/* XXX not supported yet */
+#define DOSFAR
+#define DOSTEXTFAR
+#undef DOSDATA
+#undef DOSTEXT
+#define DOSDATA(x) (*(typeof(x) FAR *)MK_FP(DosDataSeg, (size_t)&(x)))
+#define DOSTEXT(x) (*(typeof(x) FAR *)MK_FP(DosTextSeg, (size_t)&(x)))
+
+#elif !defined(I86)
 
 #define DOSFAR
 #define DOSTEXTFAR

kernel/init-mod.h

@@ -220,6 +220,9 @@ VOID ASMCFUNC FAR int2a_handler(void);
 VOID ASMCFUNC FAR int2f_handler(void);
 VOID ASMCFUNC FAR cpm_entry(void);
 
+#define cpm_entry DOSDATA(cpm_entry)
+#define int29_handler DOSTEXT(int29_handler)
+
 /* kernel.asm */
 VOID ASMCFUNC FAR init_call_p_0(struct config FAR *Config); /* P_0, actually */
 
@@ -235,6 +238,7 @@ int VA_CDECL init_sprintf(char * buff, CONST char * fmt, ...);
 
 /* procsupt.asm */
 VOID ASMCFUNC FAR got_cbreak(void);
+#define got_cbreak DOSTEXT(got_cbreak)
 
 /* initclk.c */
 extern void Init_clk_driver(void);
@@ -244,6 +248,7 @@ extern UWORD HMAFree;            /* first byte in HMA not yet used      */
 extern unsigned CurrentKernelSegment;
 #ifdef __GNUC__
 extern struct _KernelConfig ASM LowKernelConfig;
+#define LowKernelConfig *(typeof(LowKernelConfig) FAR *)MK_FP(DOS_PSP, &LowKernelConfig)
 #else
 extern struct _KernelConfig FAR ASM LowKernelConfig;
 #endif
@@ -258,13 +263,16 @@ extern char master_env[128];
 extern struct lol FAR *LoL;
 
 extern struct dhdr DOSTEXTFAR ASM blk_dev; /* Block device (Disk) driver           */
+#define blk_dev DOSTEXT(blk_dev)
 
 extern struct buffer FAR *DOSFAR firstAvailableBuf; /* first 'available' buffer   */
+#define firstAvailableBuf DOSDATA(firstAvailableBuf)
 #ifdef __GNUC__
 extern struct lol ASM DATASTART;
 #else
 extern struct lol ASM FAR DATASTART;
 #endif
+#define DATASTART DOSDATA(DATASTART)
 
 extern BYTE DOSFAR ASM _HMATextAvailable;    /* first byte of available CODE area    */
 #ifdef __GNUC__
@@ -275,13 +283,18 @@ extern BYTE FAR ASM _HMATextStart[];          /* first byte of HMAable CODE area
 extern BYTE FAR ASM _HMATextEnd[];
 #endif
 extern BYTE DOSFAR ASM break_ena;  /* break enabled flag                   */
+#define break_ena DOSDATA(break_ena)
 extern BYTE DOSFAR ASM _InitTextStart[],     /* first available byte of ram          */
   DOSFAR ASM _InitTextEnd[],
   DOSFAR ASM ReturnAnyDosVersionExpected,
   DOSFAR ASM HaltCpuWhileIdle;
+#define ReturnAnyDosVersionExpected DOSDATA(ReturnAnyDosVersionExpected)
+#define HaltCpuWhileIdle DOSDATA(HaltCpuWhileIdle)
 
 extern BYTE DOSFAR ASM internal_data[];
+#define internal_data DOSDATA(internal_data)
 extern unsigned char DOSTEXTFAR ASM kbdType;
+#define kbdType DOSTEXT(kbdType)
 
 extern struct {
   char  ThisIsAConstantOne;
@@ -290,23 +303,29 @@ extern struct {
   struct CountrySpecificInfo C;
   
 } DOSFAR ASM nlsCountryInfoHardcoded;
+#define nlsCountryInfoHardcoded DOSDATA(nlsCountryInfoHardcoded)
+#define nlsPackageHardcoded DOSDATA(nlsPackageHardcoded)
 
 /*
     data shared between DSK.C and INITDISK.C
 */
 
 extern UWORD DOSFAR LBA_WRITE_VERIFY;
+#define LBA_WRITE_VERIFY DOSDATA(LBA_WRITE_VERIFY)
 
 /* original interrupt vectors, at 70:xxxx */
 extern struct lowvec {
   unsigned char intno;
   intvec isv;
 } DOSTEXTFAR ASM intvec_table[5];
+#define intvec_table DOSTEXT(intvec_table)
 
 /* floppy parameter table, at 70:xxxx */
 extern unsigned char DOSTEXTFAR ASM int1e_table[0xe];
+#define int1e_table DOSTEXT(int1e_table)
 
 extern char DOSFAR DiskTransferBuffer[/*MAX_SEC_SIZE*/]; /* in dsk.c */
+#define DiskTransferBuffer DOSDATA(DiskTransferBuffer)
 
 struct RelocationTable {
   UBYTE jmpFar;
@@ -327,8 +346,11 @@ struct RelocatedEntry {
 extern struct RelocationTable
    DOSFAR ASM _HMARelocationTableStart[],
    DOSFAR ASM _HMARelocationTableEnd[];
+#define _HMARelocationTableStart DOSDATA(_HMARelocationTableStart)
+#define _HMARelocationTableEnd DOSDATA(_HMARelocationTableEnd)
 
 extern void FAR *DOSFAR ASM XMSDriverAddress;
+#define XMSDriverAddress DOSDATA(XMSDriverAddress)
 extern VOID ASMPASCAL FAR _EnableA20(VOID);
 extern VOID ASMPASCAL FAR _DisableA20(VOID);
 

kernel/inithma.c

@@ -312,7 +312,14 @@ void MoveKernel(unsigned NewKernelSegment)
   unsigned jmpseg = CurrentKernelSegment;
  
   if (CurrentKernelSegment == 0)
+#ifdef __GNUC__
+    {
+      extern char TGROUP[] asm("TGROUP");
+      CurrentKernelSegment = (unsigned)TGROUP;
+    }
+#else
     CurrentKernelSegment = FP_SEG(_HMATextEnd);
+#endif
 
   if (CurrentKernelSegment == 0xffff)
     return;

kernel/main.c

@@ -271,10 +271,10 @@ STATIC void setup_int_vectors(void)
   for (plvec = intvec_table; plvec < intvec_table + 5; plvec++)
     plvec->isv = getvec(plvec->intno);
   for (i = 0x23; i <= 0x3f; i++)
-    setvec(i, empty_handler);
+    setvec(i, DOSDATA(empty_handler));
   HaltCpuWhileIdle = 0;
   for (pvec = vectors; pvec < vectors + (sizeof vectors/sizeof *pvec); pvec++)
-    setvec(pvec->intno, (intvec)MK_FP(FP_SEG(empty_handler), pvec->handleroff));
+    setvec(pvec->intno, (intvec)MK_FP(FP_SEG(DOSDATA(empty_handler)), pvec->handleroff));
   pokeb(0, 0x30 * 4, 0xea);
   pokel(0, 0x30 * 4 + 1, (ULONG)cpm_entry);