src/memory.c

Fri, 18 Apr 2014 01:26:01 -0600

author
andrew@localhost
date
Fri, 18 Apr 2014 01:26:01 -0600
changeset 150
c19afa2c81db
parent 139
d91346487fe9
child 151
b63a3999e2e7
permissions
-rw-r--r--

treat all DMA reads/writes as kernel mode (previously it would depend on whether the processor happens to be in user mode or kernel mode when the DMA completes, which is totally incorrect); handle 32-bit accesses that straddle page boundaries properly (all 32-bit accesses are now split into two 16-bit accesses); allow reads to the entire zero page, rather than just address 0

     1 #include <stdio.h>
     2 #include <stdlib.h>
     3 #include <stdint.h>
     4 #include <stdbool.h>
     5 #include <assert.h>
     6 #include "musashi/m68k.h"
     7 #include "state.h"
     8 #include "utils.h"
     9 #include "memory.h"
    11 // The value which will be returned if the CPU attempts to read from empty memory
    12 // TODO (FIXME?) - need to figure out if R/W ops wrap around. This seems to appease the UNIX kernel and P4TEST.
    13 #define EMPTY 0xFFFFFFFFUL
    14 //#define EMPTY 0x55555555UL
    15 //#define EMPTY 0x00000000UL
    17 /******************
    18  * Memory mapping
    19  ******************/
    21 #define MAPRAM(addr) (((uint16_t)state.map[addr*2] << 8) + ((uint16_t)state.map[(addr*2)+1]))
    23 static uint32_t map_address_debug(uint32_t addr)
    24 {
    25 	uint16_t page = (addr >> 12) & 0x3FF;
    27 	// Look it up in the map RAM and get the physical page address
    28 	uint32_t new_page_addr = MAPRAM(page) & 0x3FF;
    29 	return (new_page_addr << 12) + (addr & 0xFFF);
    30 }
    32 uint32_t mapAddr(uint32_t addr, bool writing)/*{{{*/
    33 {
    34 	if (addr < 0x400000) {
    35 		// RAM access. Check against the Map RAM
    36 		// Start by getting the original page address
    37 		uint16_t page = (addr >> 12) & 0x3FF;
    39 		// Look it up in the map RAM and get the physical page address
    40 		uint32_t new_page_addr = MAPRAM(page) & 0x3FF;
    42 		// Update the Page Status bits
    43 		uint8_t pagebits = (MAPRAM(page) >> 13) & 0x03;
    44 		// Pagebits --
    45 		//   0 = not present
    46 		//   1 = present but not accessed
    47 		//   2 = present, accessed (read from)
    48 		//   3 = present, dirty (written to)
    49 		switch (pagebits) {
    50 			case 0:
    51 				// Page not present
    52 				// This should cause a page fault
    53 				LOGS("Whoa! Pagebit update, when the page is not present!");
    54 				break;
    56 			case 1:
    57 				// Page present -- first access
    58 				state.map[page*2] &= 0x9F;	// turn off "present" bit (but not write enable!)
    59 				if (writing)
    60 					state.map[page*2] |= 0x60;		// Page written to (dirty)
    61 				else
    62 					state.map[page*2] |= 0x40;		// Page accessed but not written
    63 				break;
    65 			case 2:
    66 			case 3:
    67 				// Page present, 2nd or later access
    68 				if (writing)
    69 					state.map[page*2] |= 0x60;		// Page written to (dirty)
    70 				break;
    71 		}
    73 		// Return the address with the new physical page spliced in
    74 		return (new_page_addr << 12) + (addr & 0xFFF);
    75 	} else {
    76 		// I/O, VRAM or MapRAM space; no mapping is performed or required
    77 		// TODO: assert here?
    78 		return addr;
    79 	}
    80 }/*}}}*/
    82 MEM_STATUS checkMemoryAccess(uint32_t addr, bool writing, bool dma)/*{{{*/
    83 {
    84 	// Get the page bits for this page.
    85 	uint16_t page = (addr >> 12) & 0x3FF;
    86 	uint8_t pagebits = (MAPRAM(page) >> 13) & 0x07;
    88 	// Check page is present (but only for RAM zone)
    89 	if ((addr < 0x400000) && ((pagebits & 0x03) == 0)) {
    90 		LOG("Page not mapped in: addr %08X, page %04X, mapbits %04X", addr, page, MAPRAM(page));
    91 		return MEM_PAGEFAULT;
    92 	}
    94 	// Are we in Supervisor mode?
    95 	if (dma || (m68k_get_reg(NULL, M68K_REG_SR) & 0x2000))
    96 		// Yes. We can do anything we like.
    97 		return MEM_ALLOWED;
    99 	// If we're here, then we must be in User mode.
   100 	// Check that the user didn't access memory outside of the RAM area
   101 	if (addr >= 0x400000) {
   102 		LOGS("User accessed privileged memory");
   103 		return MEM_UIE;
   104 	}
   106 	// User attempt to access the kernel
   107 	// A19, A20, A21, A22 low (kernel access): RAM addr before paging; not in Supervisor mode
   108 	if (((addr >> 19) & 0x0F) == 0 && !(!writing && addr <= 0x1000)) {
   109 		LOGS("Attempt by user code to access kernel space");
   110 		return MEM_KERNEL;
   111 	}
   113 	// Check page is write enabled
   114 	if (writing && ((pagebits & 0x04) == 0)) {
   115 		LOG("Page not write enabled: inaddr %08X, page %04X, mapram %04X [%02X %02X], pagebits %d",
   116 				addr, page, MAPRAM(page), state.map[page*2], state.map[(page*2)+1], pagebits);
   117 		return MEM_PAGE_NO_WE;
   118 	}
   119 	// Page access allowed.
   120 	return MEM_ALLOWED;
   121 }/*}}}*/
   123 #define _ACCESS_CHECK_WR_BYTE(address)								\
   124 	do {															\
   125 		switch (st = checkMemoryAccess(address, true, false)) {			\
   126 			case MEM_ALLOWED:										\
   127 				/* Access allowed */								\
   128 				break;												\
   129 			case MEM_PAGEFAULT:										\
   130 				/* Page fault */									\
   131 				state.genstat = 0x8BFF | (state.pie ? 0x0400 : 0);	\
   132 				fault = true;										\
   133 				break;												\
   134 			case MEM_UIE:											\
   135 				/* User access to memory above 4MB */				\
   136 				state.genstat = 0x9AFF | (state.pie ? 0x0400 : 0);	\
   137 				fault = true;										\
   138 				break;												\
   139 			case MEM_KERNEL:										\
   140 			case MEM_PAGE_NO_WE:									\
   141 				/* kernel access or page not write enabled */		\
   142 				/* XXX: is this the correct value? */				\
   143 				state.genstat = 0x9BFF | (state.pie ? 0x0400 : 0);	\
   144 				fault = true;										\
   145 				break;												\
   146 		}															\
   147 	}while (0)
   151 /********************************************************
   152  * m68k memory read/write support functions for Musashi
   153  ********************************************************/
   155 /**
   156  * @brief	Check memory access permissions for a write operation.
   157  * @note	This used to be a single macro (merged with ACCESS_CHECK_RD), but
   158  * 			gcc throws warnings when you have a return-with-value in a void
   159  * 			function, even if the return-with-value is completely unreachable.
   160  * 			Similarly it doesn't like it if you have a return without a value
   161  * 			in a non-void function, even if it's impossible to ever reach the
   162  * 			return-with-no-value. UGH!
   163  */
   164 /*{{{ macro: ACCESS_CHECK_WR(address, bits)*/
   165 #define ACCESS_CHECK_WR(address, bits)								\
   166 	do {															\
   167 		bool fault = false;											\
   168 		MEM_STATUS st;												\
   169 		_ACCESS_CHECK_WR_BYTE(address);								\
   170 		if (!fault && bits == 32									\
   171 				&& ((address + 3) & ~0xfff) != ((address & ~0xfff))){	\
   172 			_ACCESS_CHECK_WR_BYTE(address + 3);						\
   173 		}															\
   174 		if (fault) {												\
   175 			if (bits >= 16)											\
   176 				state.bsr0 = 0x7C00;								\
   177 			else													\
   178 				state.bsr0 = (address & 1) ? 0x7E00 : 0x7D00;		\
   179 			state.bsr0 |= (address >> 16);							\
   180 			state.bsr1 = address & 0xffff;							\
   181 			LOG("Bus Error while writing, addr %08X, statcode %d", address, st);		\
   182 			if (state.ee) m68k_pulse_bus_error();					\
   183 			return;													\
   184 		}															\
   185 	} while (0)
   186 /*}}}*/
   188 #define _ACCESS_CHECK_RD_BYTE(address)									\
   189 	do {															\
   190 		switch (st = checkMemoryAccess(address, false, false)) {	\
   191 			case MEM_ALLOWED:										\
   192 				/* Access allowed */								\
   193 				break;												\
   194 			case MEM_PAGEFAULT:										\
   195 				/* Page fault */									\
   196 				state.genstat = 0xCBFF | (state.pie ? 0x0400 : 0);	\
   197 				fault = true;										\
   198 				break;												\
   199 			case MEM_UIE:											\
   200 				/* User access to memory above 4MB */				\
   201 				state.genstat = 0xDAFF | (state.pie ? 0x0400 : 0);	\
   202 				fault = true;										\
   203 				break;												\
   204 			case MEM_KERNEL:										\
   205 			case MEM_PAGE_NO_WE:									\
   206 				/* kernel access or page not write enabled */		\
   207 				/* XXX: is this the correct value? */				\
   208 				state.genstat = 0xDBFF | (state.pie ? 0x0400 : 0);	\
   209 				fault = true;										\
   210 				break;												\
   211 		}															\
   212 	} while (0)	
   214 /**
   215  * @brief Check memory access permissions for a read operation.
   216  * @note	This used to be a single macro (merged with ACCESS_CHECK_WR), but
   217  * 			gcc throws warnings when you have a return-with-value in a void
   218  * 			function, even if the return-with-value is completely unreachable.
   219  * 			Similarly it doesn't like it if you have a return without a value
   220  * 			in a non-void function, even if it's impossible to ever reach the
   221  * 			return-with-no-value. UGH!
   222  */
   223 /*{{{ macro: ACCESS_CHECK_RD(address, bits)*/
   224 #define ACCESS_CHECK_RD(address, bits)								\
   225 	do {															\
   226 		bool fault = false;											\
   227 		uint32_t faultAddr = address;								\
   228 		MEM_STATUS st;												\
   229 		_ACCESS_CHECK_RD_BYTE(address);								\
   230 		if (!fault && bits == 32									\
   231 				&& ((address + 2) & ~0xfff) != (address & ~0xfff)){	\
   232 			_ACCESS_CHECK_RD_BYTE(address + 2);						\
   233 			if (fault) faultAddr = address + 2;						\
   234 		}															\
   235 																	\
   236 		if (fault) {												\
   237 			if (bits >= 16)											\
   238 				state.bsr0 = 0x7C00;								\
   239 			else													\
   240 				state.bsr0 = (faultAddr & 1) ? 0x7E00 : 0x7D00;		\
   241 			state.bsr0 |= (faultAddr >> 16);							\
   242 			state.bsr1 = faultAddr & 0xffff;							\
   243 			LOG("Bus Error while reading, addr %08X, statcode %d", faultAddr, st);		\
   244 			if (state.ee) m68k_pulse_bus_error();					\
   245 			if (bits >= 32)											\
   246 				return EMPTY & 0xFFFFFFFF;									\
   247 			else													\
   248 				return EMPTY & ((1ULL << bits)-1);								\
   249 		}															\
   250 	} while (0)
   251 /*}}}*/
   253 bool access_check_dma(int reading)
   254 {
   255 	// Check memory access permissions
   256 	bool access_ok = false;
   257 	switch (checkMemoryAccess(state.dma_address, !reading, true)) {
   258 		case MEM_PAGEFAULT:
   259 			// Page fault
   260 			state.genstat = 0xABFF
   261 				| (reading ? 0x4000 : 0)
   262 				| (state.pie ? 0x0400 : 0);
   263 			access_ok = false;
   264 			break;
   266 		case MEM_UIE:
   267 			// User access to memory above 4MB
   268 			// FIXME? Shouldn't be possible with DMA... assert this?
   269 			state.genstat = 0xBAFF
   270 				| (reading ? 0x4000 : 0)
   271 				| (state.pie ? 0x0400 : 0);
   272 			access_ok = false;
   273 			break;
   275 		case MEM_KERNEL:
   276 		case MEM_PAGE_NO_WE:
   277 			// Kernel access or page not write enabled
   278 			/* XXX: is this correct? */
   279 			state.genstat = 0xBBFF
   280 				| (reading ? 0x4000 : 0)
   281 				| (state.pie ? 0x0400 : 0);
   282 			access_ok = false;
   283 			break;
   285 		case MEM_ALLOWED:
   286 			access_ok = true;
   287 			break;
   288 	}
   289 	if (!access_ok) {
   290 		state.bsr0 = 0x3C00;
   291 		state.bsr0 |= (state.dma_address >> 16);
   292 		state.bsr1 = state.dma_address & 0xffff;
   293 		if (state.ee) m68k_set_irq(7);
   294 		printf("BUS ERROR FROM DMA: genstat=%04X, bsr0=%04X, bsr1=%04X\n", state.genstat, state.bsr0, state.bsr1);
   295 	}
   296 	return (access_ok);
   297 }
   299 // Logging macros
   300 #define LOG_NOT_HANDLED_R(bits)															\
   301 	if (!handled) printf("unhandled read%02d, addr=0x%08X\n", bits, address);
   303 #define LOG_NOT_HANDLED_W(bits)															\
   304 	if (!handled) printf("unhandled write%02d, addr=0x%08X, data=0x%08X\n", bits, address, data);
   306 /********************************************************
   307  * I/O read/write functions
   308  ********************************************************/
   310 /**
   311  * Issue a warning if a read operation is made with an invalid size
   312  */
   313 inline static void ENFORCE_SIZE(int bits, uint32_t address, bool read, int allowed, char *regname)
   314 {
   315 	assert((bits == 8) || (bits == 16) || (bits == 32));
   316 	if ((bits & allowed) == 0) {
   317 		printf("WARNING: %s 0x%08X (%s) with invalid size %d!\n", read ? "read from" : "write to", address, regname, bits);
   318 	}
   319 }
   321 inline static void ENFORCE_SIZE_R(int bits, uint32_t address, int allowed, char *regname)
   322 {
   323 	ENFORCE_SIZE(bits, address, true, allowed, regname);
   324 }
   326 inline static void ENFORCE_SIZE_W(int bits, uint32_t address, int allowed, char *regname)
   327 {
   328 	ENFORCE_SIZE(bits, address, false, allowed, regname);
   329 }
   331 void IoWrite(uint32_t address, uint32_t data, int bits)/*{{{*/
   332 {
   333 	bool handled = false;
   335 	if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   336 		// I/O register space, zone A
   337 		switch (address & 0x0F0000) {
   338 			case 0x010000:				// General Status Register
   339 				if (bits == 16)
   340 					state.genstat = (data & 0xffff);
   341 				else if (bits == 8) {
   342 					if (address & 0)
   343 						state.genstat = data;
   344 					else
   345 						state.genstat = data << 8;
   346 				}
   347 				handled = true;
   348 				break;
   349 			case 0x030000:				// Bus Status Register 0
   350 				break;
   351 			case 0x040000:				// Bus Status Register 1
   352 				break;
   353 			case 0x050000:				// Phone status
   354 				break;
   355 			case 0x060000:				// DMA Count
   356 				ENFORCE_SIZE_W(bits, address, 16, "DMACOUNT");
   357 				state.dma_count = (data & 0x3FFF);
   358 				state.idmarw = ((data & 0x4000) == 0x4000);
   359 				state.dmaen = ((data & 0x8000) == 0x8000);
   360 				// This handles the "dummy DMA transfer" mentioned in the docs
   361 				// disabled because it causes the floppy test to fail
   362 #if 0
   363 				if (!state.idmarw){
   364 					if (access_check_dma(true)){
   365 						uint32_t newAddr = mapAddr(state.dma_address, true);
   366 						// RAM access
   367 						if (newAddr <= 0x1fffff)
   368 							WR16(state.base_ram, newAddr, state.base_ram_size - 1, 0xFF);
   369 						else if (address <= 0x3FFFFF)
   370 							WR16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1, 0xFF);
   371 					}
   372 				}
   373 #endif
   374 				state.dma_count++;
   375 				handled = true;
   376 				break;
   377 			case 0x070000:				// Line Printer Status Register
   378 				break;
   379 			case 0x080000:				// Real Time Clock
   380 				break;
   381 			case 0x090000:				// Phone registers
   382 				switch (address & 0x0FF000) {
   383 					case 0x090000:		// Handset relay
   384 					case 0x098000:
   385 						break;
   386 					case 0x091000:		// Line select 2
   387 					case 0x099000:
   388 						break;
   389 					case 0x092000:		// Hook relay 1
   390 					case 0x09A000:
   391 						break;
   392 					case 0x093000:		// Hook relay 2
   393 					case 0x09B000:
   394 						break;
   395 					case 0x094000:		// Line 1 hold
   396 					case 0x09C000:
   397 						break;
   398 					case 0x095000:		// Line 2 hold
   399 					case 0x09D000:
   400 						break;
   401 					case 0x096000:		// Line 1 A-lead
   402 					case 0x09E000:
   403 						break;
   404 					case 0x097000:		// Line 2 A-lead
   405 					case 0x09F000:
   406 						break;
   407 				}
   408 				break;
   409 			case 0x0A0000:				// Miscellaneous Control Register
   410 				ENFORCE_SIZE_W(bits, address, 16, "MISCCON");
   411 				// TODO: handle the ctrl bits properly
   412 				if (data & 0x8000){
   413 					state.timer_enabled = 1;
   414 				}else{
   415 					state.timer_enabled = 0;
   416 					state.timer_asserted = 0;
   417 				}
   418 				state.dma_reading = (data & 0x4000);
   419 				if (state.leds != ((~data & 0xF00) >> 8)) {
   420 					state.leds = (~data & 0xF00) >> 8;
   421 #ifdef SHOW_LEDS
   422 					printf("LEDs: %s %s %s %s\n",
   423 							(state.leds & 8) ? "R" : "-",
   424 							(state.leds & 4) ? "G" : "-",
   425 							(state.leds & 2) ? "Y" : "-",
   426 							(state.leds & 1) ? "R" : "-");
   427 #endif
   428 				}
   429 				handled = true;
   430 				break;
   431 			case 0x0B0000:				// TM/DIALWR
   432 				break;
   433 			case 0x0C0000:				// Clear Status Register
   434 				state.genstat = 0xFFFF;
   435 				state.bsr0 = 0xFFFF;
   436 				state.bsr1 = 0xFFFF;
   437 				handled = true;
   438 				break;
   439 			case 0x0D0000:				// DMA Address Register
   440 				if (address & 0x004000) {
   441 					// A14 high -- set most significant bits
   442 					state.dma_address = (state.dma_address & 0x1fe) | ((address & 0x3ffe) << 8);
   443 				} else {
   444 					// A14 low -- set least significant bits
   445 					state.dma_address = (state.dma_address & 0x3ffe00) | (address & 0x1fe);
   446 				}
   447 				handled = true;
   448 				break;
   449 			case 0x0E0000:				// Disk Control Register
   450 				{
   451 					bool fd_selected;
   452 					bool hd_selected;
   453 					ENFORCE_SIZE_W(bits, address, 16, "DISKCON");
   454 					// B7 = FDD controller reset
   455 					if ((data & 0x80) == 0) wd2797_reset(&state.fdc_ctx);
   456 					// B6 = drive 0 select
   457 					fd_selected = (data & 0x40) != 0;
   458 					// B5 = motor enable -- TODO
   459 					// B4 = HDD controller reset
   460 					if ((data & 0x10) == 0) wd2010_reset(&state.hdc_ctx);
   461 					// B3 = HDD0 select
   462 					hd_selected = (data & 0x08) != 0;
   463 					// B2,1,0 = HDD0 head select -- TODO?
   464 					if (hd_selected && !state.hd_selected){
   465 						state.fd_selected = false;
   466 						state.hd_selected = true;
   467 					}else if (fd_selected && !state.fd_selected){
   468 						state.hd_selected = false;
   469 						state.fd_selected = true;
   470 					}
   471 					handled = true;
   472 					break;
   473 				}
   474 			case 0x0F0000:				// Line Printer Data Register
   475 				break;
   476 		}
   477 	} else if ((address >= 0xC00000) && (address <= 0xFFFFFF)) {
   478 		// I/O register space, zone B
   479 		switch (address & 0xF00000) {
   480 			case 0xC00000:				// Expansion slots
   481 			case 0xD00000:
   482 				switch (address & 0xFC0000) {
   483 					case 0xC00000:		// Expansion slot 0
   484 					case 0xC40000:		// Expansion slot 1
   485 					case 0xC80000:		// Expansion slot 2
   486 					case 0xCC0000:		// Expansion slot 3
   487 					case 0xD00000:		// Expansion slot 4
   488 					case 0xD40000:		// Expansion slot 5
   489 					case 0xD80000:		// Expansion slot 6
   490 					case 0xDC0000:		// Expansion slot 7
   491 						fprintf(stderr, "NOTE: WR%d to expansion card space, addr=0x%08X, data=0x%08X\n", bits, address, data);
   492 						handled = true;
   493 						break;
   494 				}
   495 				break;
   496 			case 0xE00000:				// HDC, FDC, MCR2 and RTC data bits
   497 			case 0xF00000:
   498 				switch (address & 0x070000) {
   499 					case 0x000000:		// [ef][08]xxxx ==> WD2010 hard disc controller
   500 						wd2010_write_reg(&state.hdc_ctx, (address >> 1) & 7, data);
   501 						handled = true;
   502 						break;
   503 					case 0x010000:		// [ef][19]xxxx ==> WD2797 floppy disc controller
   504 						/*ENFORCE_SIZE_W(bits, address, 16, "FDC REGISTERS");*/
   505 						wd2797_write_reg(&state.fdc_ctx, (address >> 1) & 3, data);
   506 						handled = true;
   507 						break;
   508 					case 0x020000:		// [ef][2a]xxxx ==> Miscellaneous Control Register 2
   509 						// MCR2 - UNIX PC Rev. P5.1 HDD head select b3 and potential HDD#2 select
   510 						wd2010_write_reg(&state.hdc_ctx, UNIXPC_REG_MCR2, data);
   511 						handled = true;
   512 						break;
   513 					case 0x030000:		// [ef][3b]xxxx ==> Real Time Clock data bits
   514 						break;
   515 					case 0x040000:		// [ef][4c]xxxx ==> General Control Register
   516 						switch (address & 0x077000) {
   517 							case 0x040000:		// [ef][4c][08]xxx ==> EE
   518 								// Error Enable. If =0, Level7 intrs and bus errors are masked.
   519 								ENFORCE_SIZE_W(bits, address, 16, "EE");
   520 								state.ee = ((data & 0x8000) == 0x8000);
   521 								handled = true;
   522 								break;
   523 							case 0x041000:		// [ef][4c][19]xxx ==> PIE
   524 								ENFORCE_SIZE_W(bits, address, 16, "PIE");
   525 								state.pie = ((data & 0x8000) == 0x8000);
   526 								handled = true;
   527 								break;
   528 							case 0x042000:		// [ef][4c][2A]xxx ==> BP
   529 								break;
   530 							case 0x043000:		// [ef][4c][3B]xxx ==> ROMLMAP
   531 								ENFORCE_SIZE_W(bits, address, 16, "ROMLMAP");
   532 								state.romlmap = ((data & 0x8000) == 0x8000);
   533 								handled = true;
   534 								break;
   535 							case 0x044000:		// [ef][4c][4C]xxx ==> L1 MODEM
   536 								ENFORCE_SIZE_W(bits, address, 16, "L1 MODEM");
   537 								break;
   538 							case 0x045000:		// [ef][4c][5D]xxx ==> L2 MODEM
   539 								ENFORCE_SIZE_W(bits, address, 16, "L2 MODEM");
   540 								break;
   541 							case 0x046000:		// [ef][4c][6E]xxx ==> D/N CONNECT
   542 								ENFORCE_SIZE_W(bits, address, 16, "D/N CONNECT");
   543 								break;
   544 							case 0x047000:		// [ef][4c][7F]xxx ==> Whole screen reverse video
   545 								ENFORCE_SIZE_W(bits, address, 16, "WHOLE SCREEN REVERSE VIDEO");
   546 								break;
   547 						}
   548 					case 0x050000:		// [ef][5d]xxxx ==> 8274
   549 						break;
   550 					case 0x060000:		// [ef][6e]xxxx ==> Control regs
   551 						switch (address & 0x07F000) {
   552 							default:
   553 								break;
   554 						}
   555 						break;
   556 					case 0x070000:		// [ef][7f]xxxx ==> 6850 Keyboard Controller
   557 						// TODO: figure out which sizes are valid (probably just 8 and 16)
   558 						// ENFORCE_SIZE_W(bits, address, 16, "KEYBOARD CONTROLLER");
   559 						if (bits == 8) {
   560 							printf("KBD WR %02X => %02X\n", (address >> 1) & 3, data);
   561 							keyboard_write(&state.kbd, (address >> 1) & 3, data);
   562 							handled = true;
   563 						} else if (bits == 16) {
   564 							printf("KBD WR %02X => %04X\n", (address >> 1) & 3, data);
   565 							keyboard_write(&state.kbd, (address >> 1) & 3, data >> 8);
   566 							handled = true;
   567 						}
   568 						break;
   569 				}
   570 		}
   571 	}
   573 	LOG_NOT_HANDLED_W(bits);
   574 }/*}}}*/
   576 uint32_t IoRead(uint32_t address, int bits)/*{{{*/
   577 {
   578 	bool handled = false;
   579 	uint32_t data = EMPTY & 0xFFFFFFFF;
   581 	if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   582 		// I/O register space, zone A
   583 		switch (address & 0x0F0000) {
   584 			case 0x010000:				// General Status Register
   585 				/* ENFORCE_SIZE_R(bits, address, 16, "GENSTAT"); */
   586 				if (bits == 32) {
   587 					return ((uint32_t)state.genstat << 16) + (uint32_t)state.genstat;
   588 				} else if (bits == 16) {
   589 					return (uint16_t)state.genstat;
   590 				} else {
   591 					return (uint8_t)(state.genstat & 0xff);
   592 				}
   593 				break;
   594 			case 0x030000:				// Bus Status Register 0
   595 				ENFORCE_SIZE_R(bits, address, 16, "BSR0");
   596 				return ((uint32_t)state.bsr0 << 16) + (uint32_t)state.bsr0;
   597 				break;
   598 			case 0x040000:				// Bus Status Register 1
   599 				ENFORCE_SIZE_R(bits, address, 16, "BSR1");
   600 				return ((uint32_t)state.bsr1 << 16) + (uint32_t)state.bsr1;
   601 				break;
   602 			case 0x050000:				// Phone status
   603 				ENFORCE_SIZE_R(bits, address, 8 | 16, "PHONE STATUS");
   604 				break;
   605 			case 0x060000:				// DMA Count
   606 				// TODO: U/OERR- is always inactive (bit set)... or should it be = DMAEN+?
   607 				// Bit 14 is always unused, so leave it set
   608 				ENFORCE_SIZE_R(bits, address, 16, "DMACOUNT");
   609 				return (state.dma_count & 0x3fff) | 0xC000;
   610 				break;
   611 			case 0x070000:				// Line Printer Status Register
   612 				data = 0x00120012;	// no parity error, no line printer error, no irqs from FDD or HDD
   613 				data |= wd2797_get_irq(&state.fdc_ctx) ? 0x00080008 : 0;
   614 				data |= wd2010_get_irq(&state.hdc_ctx) ? 0x00040004 : 0;
   615 				return data;
   616 				break;
   617 			case 0x080000:				// Real Time Clock
   618 				printf("READ NOTIMP: Realtime Clock\n");
   619 				break;
   620 			case 0x090000:				// Phone registers
   621 				switch (address & 0x0FF000) {
   622 					case 0x090000:		// Handset relay
   623 					case 0x098000:
   624 						break;
   625 					case 0x091000:		// Line select 2
   626 					case 0x099000:
   627 						break;
   628 					case 0x092000:		// Hook relay 1
   629 					case 0x09A000:
   630 						break;
   631 					case 0x093000:		// Hook relay 2
   632 					case 0x09B000:
   633 						break;
   634 					case 0x094000:		// Line 1 hold
   635 					case 0x09C000:
   636 						break;
   637 					case 0x095000:		// Line 2 hold
   638 					case 0x09D000:
   639 						break;
   640 					case 0x096000:		// Line 1 A-lead
   641 					case 0x09E000:
   642 						break;
   643 					case 0x097000:		// Line 2 A-lead
   644 					case 0x09F000:
   645 						break;
   646 				}
   647 				break;
   648 			case 0x0A0000:				// Miscellaneous Control Register -- write only!
   649 				handled = true;
   650 				break;
   651 			case 0x0B0000:				// TM/DIALWR
   652 				break;
   653 			case 0x0C0000:				// Clear Status Register -- write only!
   654 				handled = true;
   655 				break;
   656 			case 0x0D0000:				// DMA Address Register
   657 				break;
   658 			case 0x0E0000:				// Disk Control Register
   659 				break;
   660 			case 0x0F0000:				// Line Printer Data Register
   661 				break;
   662 		}
   663 	} else if ((address >= 0xC00000) && (address <= 0xFFFFFF)) {
   664 		// I/O register space, zone B
   665 		switch (address & 0xF00000) {
   666 			case 0xC00000:				// Expansion slots
   667 			case 0xD00000:
   668 				switch (address & 0xFC0000) {
   669 					case 0xC00000:		// Expansion slot 0
   670 					case 0xC40000:		// Expansion slot 1
   671 					case 0xC80000:		// Expansion slot 2
   672 					case 0xCC0000:		// Expansion slot 3
   673 					case 0xD00000:		// Expansion slot 4
   674 					case 0xD40000:		// Expansion slot 5
   675 					case 0xD80000:		// Expansion slot 6
   676 					case 0xDC0000:		// Expansion slot 7
   677 						fprintf(stderr, "NOTE: RD%d from expansion card space, addr=0x%08X\n", bits, address);
   678 						handled = true;
   679 						break;
   680 				}
   681 				break;
   682 			case 0xE00000:				// HDC, FDC, MCR2 and RTC data bits
   683 			case 0xF00000:
   684 				switch (address & 0x070000) {
   685 					case 0x000000:		// [ef][08]xxxx ==> WD1010 hard disc controller
   686 						return (wd2010_read_reg(&state.hdc_ctx, (address >> 1) & 7));
   688 						break;
   689 					case 0x010000:		// [ef][19]xxxx ==> WD2797 floppy disc controller
   690 						/*ENFORCE_SIZE_R(bits, address, 16, "FDC REGISTERS");*/
   691 						return wd2797_read_reg(&state.fdc_ctx, (address >> 1) & 3);
   692 						break;
   693 					case 0x020000:		// [ef][2a]xxxx ==> Miscellaneous Control Register 2
   694 						break;
   695 					case 0x030000:		// [ef][3b]xxxx ==> Real Time Clock data bits
   696 						break;
   697 					case 0x040000:		// [ef][4c]xxxx ==> General Control Register
   698 						switch (address & 0x077000) {
   699 							case 0x040000:		// [ef][4c][08]xxx ==> EE
   700 							case 0x041000:		// [ef][4c][19]xxx ==> PIE
   701 							case 0x042000:		// [ef][4c][2A]xxx ==> BP
   702 							case 0x043000:		// [ef][4c][3B]xxx ==> ROMLMAP
   703 							case 0x044000:		// [ef][4c][4C]xxx ==> L1 MODEM
   704 							case 0x045000:		// [ef][4c][5D]xxx ==> L2 MODEM
   705 							case 0x046000:		// [ef][4c][6E]xxx ==> D/N CONNECT
   706 								// All write-only registers... TODO: bus error?
   707 								handled = true;
   708 								break;
   709 							case 0x047000:		// [ef][4c][7F]xxx ==> Whole screen reverse video [FIXME: not in TRM]
   710 								break;
   711 						}
   712 						break;
   713 					case 0x050000:		// [ef][5d]xxxx ==> 8274
   714 						break;
   715 					case 0x060000:		// [ef][6e]xxxx ==> Control regs
   716 						switch (address & 0x07F000) {
   717 							default:
   718 								break;
   719 						}
   720 						break;
   721 					case 0x070000:		// [ef][7f]xxxx ==> 6850 Keyboard Controller
   722 						// TODO: figure out which sizes are valid (probably just 8 and 16)
   723 						//ENFORCE_SIZE_R(bits, address, 16, "KEYBOARD CONTROLLER");
   724 						{
   725 							if (bits == 8) {
   726 								return keyboard_read(&state.kbd, (address >> 1) & 3);
   727 							} else {
   728 								return keyboard_read(&state.kbd, (address >> 1) & 3) << 8;
   729 							}
   730 							return data;
   731 						}
   732 						break;
   733 				}
   734 		}
   735 	}
   737 	LOG_NOT_HANDLED_R(bits);
   739 	return data;
   740 }/*}}}*/
   743 /********************************************************
   744  * m68k memory read/write support functions for Musashi
   745  ********************************************************/
   748 static uint16_t ram_read_16(uint32_t address)
   749 {
   750 	if (address <= 0x1fffff) {
   751 		// Base memory wraps around
   752 		return RD16(state.base_ram, address, state.base_ram_size - 1);
   753 	} else {
   754 		if ((address <= (state.exp_ram_size + 0x200000 - 1)) && (address >= 0x200000)){
   755 			return RD16(state.exp_ram, address - 0x200000, state.exp_ram_size - 1);
   756 		}else
   757 			return EMPTY & 0xffff;
   758 	}
   759 }
   761 /**
   762  * @brief Read M68K memory, 32-bit
   763  */
   764 uint32_t m68k_read_memory_32(uint32_t address)/*{{{*/
   765 {
   766 	uint32_t data = EMPTY & 0xFFFFFFFF;
   768 	// If ROMLMAP is set, force system to access ROM
   769 	if (!state.romlmap)
   770 		address |= 0x800000;
   772 	// Check access permissions
   773 	ACCESS_CHECK_RD(address, 32);
   775 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   776 		// ROM access
   777 		return RD32(state.rom, address, ROM_SIZE - 1);
   778 	} else if (address <= 0x3fffff) {
   779 		// RAM access
   780 		uint32_t newAddr = mapAddr(address, false);
   781 		// Base memory wraps around
   782 		data = ((ram_read_16(newAddr) << 16) | 
   783 			ram_read_16(mapAddr(address + 2, false)));
   785 		return (data);
   786 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   787 		// I/O register space, zone A
   788 		switch (address & 0x0F0000) {
   789 			case 0x000000:				// Map RAM access
   790 				if (address > 0x4007FF) fprintf(stderr, "NOTE: RD32 from MapRAM mirror, addr=0x%08X\n", address);
   791 				return RD32(state.map, address, 0x7FF);
   792 				break;
   793 			case 0x020000:				// Video RAM
   794 				if (address > 0x427FFF) fprintf(stderr, "NOTE: RD32 from VideoRAM mirror, addr=0x%08X\n", address);
   795 				return RD32(state.vram, address, 0x7FFF);
   796 				break;
   797 			default:
   798 				return IoRead(address, 32);
   799 		}
   800 	} else {
   801 		return IoRead(address, 32);
   802 	}
   804 	return data;
   805 }/*}}}*/
   807 /**
   808  * @brief Read M68K memory, 16-bit
   809  */
   810 uint32_t m68k_read_memory_16(uint32_t address)/*{{{*/
   811 {
   812 	uint16_t data = EMPTY & 0xFFFF;
   814 	// If ROMLMAP is set, force system to access ROM
   815 	if (!state.romlmap)
   816 		address |= 0x800000;
   818 	// Check access permissions
   819 	ACCESS_CHECK_RD(address, 16);
   821 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   822 		// ROM access
   823 		data = RD16(state.rom, address, ROM_SIZE - 1);
   824 	} else if (address <= 0x3fffff) {
   825 		// RAM access
   826 		uint32_t newAddr = mapAddr(address, false);
   827 		if (newAddr <= 0x1fffff) {
   828 			// Base memory wraps around
   829 			return RD16(state.base_ram, newAddr, state.base_ram_size - 1);
   830 		} else {
   831 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
   832 				return RD16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
   833 			else
   834 				return EMPTY & 0xffff;
   835 		}
   836 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   837 		// I/O register space, zone A
   838 		switch (address & 0x0F0000) {
   839 			case 0x000000:				// Map RAM access
   840 				if (address > 0x4007FF) fprintf(stderr, "NOTE: RD16 from MapRAM mirror, addr=0x%08X\n", address);
   841 				data = RD16(state.map, address, 0x7FF);
   842 				break;
   843 			case 0x020000:				// Video RAM
   844 				if (address > 0x427FFF) fprintf(stderr, "NOTE: RD16 from VideoRAM mirror, addr=0x%08X\n", address);
   845 				data = RD16(state.vram, address, 0x7FFF);
   846 				break;
   847 			default:
   848 				data = IoRead(address, 16);
   849 		}
   850 	} else {
   851 		data = IoRead(address, 16);
   852 	}
   854 	return data;
   855 }/*}}}*/
   857 /**
   858  * @brief Read M68K memory, 8-bit
   859  */
   860 uint32_t m68k_read_memory_8(uint32_t address)/*{{{*/
   861 {
   862 	uint8_t data = EMPTY & 0xFF;
   864 	// If ROMLMAP is set, force system to access ROM
   865 	if (!state.romlmap)
   866 		address |= 0x800000;
   868 	// Check access permissions
   869 	ACCESS_CHECK_RD(address, 8);
   871 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   872 		// ROM access
   873 		data = RD8(state.rom, address, ROM_SIZE - 1);
   874 	} else if (address <= 0x3fffff) {
   875 		// RAM access
   876 		uint32_t newAddr = mapAddr(address, false);
   877 		if (newAddr <= 0x1fffff) {
   878 			// Base memory wraps around
   879 			return RD8(state.base_ram, newAddr, state.base_ram_size - 1);
   880 		} else {
   881 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
   882 				return RD8(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
   883 			else
   884 				return EMPTY & 0xff;
   885 		}
   886 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   887 		// I/O register space, zone A
   888 		switch (address & 0x0F0000) {
   889 			case 0x000000:				// Map RAM access
   890 				if (address > 0x4007FF) fprintf(stderr, "NOTE: RD8 from MapRAM mirror, addr=0x%08X\n", address);
   891 				data = RD8(state.map, address, 0x7FF);
   892 				break;
   893 			case 0x020000:				// Video RAM
   894 				if (address > 0x427FFF) fprintf(stderr, "NOTE: RD8 from VideoRAM mirror, addr=0x%08X\n", address);
   895 				data = RD8(state.vram, address, 0x7FFF);
   896 				break;
   897 			default:
   898 				data = IoRead(address, 8);
   899 		}
   900 	} else {
   901 		data = IoRead(address, 8);
   902 	}
   904 	return data;
   905 }/*}}}*/
   908 static void ram_write_16(uint32_t address, uint32_t value)/*{{{*/
   909 {
   910 	if (address <= 0x1fffff) {
   911 		if (address < state.base_ram_size) {
   912 			WR16(state.base_ram, address, state.base_ram_size - 1, value);
   913 		}
   914 	} else {
   915 		if ((address - 0x200000) < state.exp_ram_size) {
   916 			WR16(state.exp_ram, address - 0x200000, state.exp_ram_size - 1, value);
   917 		}
   918 	}
   919 }
   921 /**
   922  * @brief Write M68K memory, 32-bit
   923  */
   924 void m68k_write_memory_32(uint32_t address, uint32_t value)/*{{{*/
   925 {
   926 	// If ROMLMAP is set, force system to access ROM
   927 	if (!state.romlmap)
   928 		address |= 0x800000;
   930 	// Check access permissions
   931 	ACCESS_CHECK_WR(address, 32);
   932 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   933 		// ROM access
   934 	} else if (address <= 0x3FFFFF) {
   935 		// RAM access
   936 		uint32_t newAddr = mapAddr(address, true);
   937 		ram_write_16(newAddr, (value & 0xffff0000) >> 16);
   938 		ram_write_16(mapAddr(address + 2, true), (value & 0xffff));
   939 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   940 		// I/O register space, zone A
   941 		switch (address & 0x0F0000) {
   942 			case 0x000000:				// Map RAM access
   943 				if (address > 0x4007FF) fprintf(stderr, "NOTE: WR32 to MapRAM mirror, addr=0x%08X\n", address);
   944 				WR32(state.map, address, 0x7FF, value);
   945 				break;
   946 			case 0x020000:				// Video RAM
   947 				if (address > 0x427FFF) fprintf(stderr, "NOTE: WR32 to VideoRAM mirror, addr=0x%08X\n", address);
   948 				WR32(state.vram, address, 0x7FFF, value);
   949 				break;
   950 			default:
   951 				IoWrite(address, value, 32);
   952 		}
   953 	} else {
   954 		IoWrite(address, value, 32);
   955 	}
   956 }/*}}}*/
   958 /**
   959  * @brief Write M68K memory, 16-bit
   960  */
   961 void m68k_write_memory_16(uint32_t address, uint32_t value)/*{{{*/
   962 {
   963 	// If ROMLMAP is set, force system to access ROM
   964 	if (!state.romlmap)
   965 		address |= 0x800000;
   967 	// Check access permissions
   968 	ACCESS_CHECK_WR(address, 16);
   970 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   971 		// ROM access
   972 	} else if (address <= 0x3FFFFF) {
   973 		// RAM access
   974 		uint32_t newAddr = mapAddr(address, true);
   976 		if (newAddr <= 0x1fffff) {
   977 			if (newAddr < state.base_ram_size) {
   978 				WR16(state.base_ram, newAddr, state.base_ram_size - 1, value);
   979 			}
   980 		} else {
   981 			if ((newAddr - 0x200000) < state.exp_ram_size) {
   982 				WR16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1, value);
   983 			}
   984 		}
   985 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   986 		// I/O register space, zone A
   987 		switch (address & 0x0F0000) {
   988 			case 0x000000:				// Map RAM access
   989 				if (address > 0x4007FF) fprintf(stderr, "NOTE: WR16 to MapRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
   990 				WR16(state.map, address, 0x7FF, value);
   991 				break;
   992 			case 0x020000:				// Video RAM
   993 				if (address > 0x427FFF) fprintf(stderr, "NOTE: WR16 to VideoRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
   994 				WR16(state.vram, address, 0x7FFF, value);
   995 				break;
   996 			default:
   997 				IoWrite(address, value, 16);
   998 		}
   999 	} else {
  1000 		IoWrite(address, value, 16);
  1002 }/*}}}*/
  1004 /**
  1005  * @brief Write M68K memory, 8-bit
  1006  */
  1007 void m68k_write_memory_8(uint32_t address, uint32_t value)/*{{{*/
  1009 	// If ROMLMAP is set, force system to access ROM
  1010 	if (!state.romlmap)
  1011 		address |= 0x800000;
  1013 	// Check access permissions
  1014 	ACCESS_CHECK_WR(address, 8);
  1016 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
  1017 		// ROM access (read only!)
  1018 	} else if (address <= 0x3FFFFF) {
  1019 		// RAM access
  1020 		uint32_t newAddr = mapAddr(address, true);
  1021 		if (newAddr <= 0x1fffff) {
  1022 			if (newAddr < state.base_ram_size) {
  1023 				WR8(state.base_ram, newAddr, state.base_ram_size - 1, value);
  1025 		} else {
  1026 			if ((newAddr - 0x200000) < state.exp_ram_size) {
  1027 				WR8(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1, value);
  1030 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
  1031 		// I/O register space, zone A
  1032 		switch (address & 0x0F0000) {
  1033 			case 0x000000:				// Map RAM access
  1034 				if (address > 0x4007FF) fprintf(stderr, "NOTE: WR8 to MapRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
  1035 				WR8(state.map, address, 0x7FF, value);
  1036 				break;
  1037 			case 0x020000:				// Video RAM
  1038 				if (address > 0x427FFF) fprintf(stderr, "NOTE: WR8 to VideoRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
  1039 				WR8(state.vram, address, 0x7FFF, value);
  1040 				break;
  1041 			default:
  1042 				IoWrite(address, value, 8);
  1044 	} else {
  1045 		IoWrite(address, value, 8);
  1047 }/*}}}*/
  1050 // for the disassembler
  1051 uint32_t m68k_read_disassembler_32(uint32_t addr)
  1053 	if (addr < 0x400000) {
  1054 		uint32_t newAddrHigh, newAddrLow;
  1055 		newAddrHigh = map_address_debug(addr);
  1056 		newAddrLow = map_address_debug(addr + 2);
  1057 		return ((ram_read_16(newAddrHigh) << 16) | 
  1058 			ram_read_16(newAddrLow));
  1060 	} else {
  1061 		printf(">>> WARNING Disassembler RD32 out of range 0x%08X\n", addr);
  1062 		return EMPTY;
  1066 uint32_t m68k_read_disassembler_16(uint32_t addr)
  1068 	if (addr < 0x400000) {
  1069 		uint16_t page = (addr >> 12) & 0x3FF;
  1070 		uint32_t new_page_addr = MAPRAM(page) & 0x3FF;
  1071 		uint32_t newAddr = (new_page_addr << 12) + (addr & 0xFFF);
  1072 		if (newAddr <= 0x1fffff) {
  1073 			if (newAddr >= state.base_ram_size)
  1074 				return EMPTY & 0xffff;
  1075 			else
  1076 				return RD16(state.base_ram, newAddr, state.base_ram_size - 1);
  1077 		} else {
  1078 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
  1079 				return RD16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
  1080 			else
  1081 				return EMPTY & 0xffff;
  1083 	} else {
  1084 		printf(">>> WARNING Disassembler RD16 out of range 0x%08X\n", addr);
  1085 		return EMPTY & 0xffff;
  1089 uint32_t m68k_read_disassembler_8 (uint32_t addr)
  1091 	if (addr < 0x400000) {
  1092 		uint16_t page = (addr >> 12) & 0x3FF;
  1093 		uint32_t new_page_addr = MAPRAM(page) & 0x3FF;
  1094 		uint32_t newAddr = (new_page_addr << 12) + (addr & 0xFFF);
  1095 		if (newAddr <= 0x1fffff) {
  1096 			if (newAddr >= state.base_ram_size)
  1097 				return EMPTY & 0xff;
  1098 			else
  1099 				return RD8(state.base_ram, newAddr, state.base_ram_size - 1);
  1100 		} else {
  1101 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
  1102 				return RD8(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
  1103 			else
  1104 				return EMPTY & 0xff;
  1106 	} else {
  1107 		printf(">>> WARNING Disassembler RD8 out of range 0x%08X\n", addr);
  1108 		return EMPTY & 0xff;