Started work on cpm disk emulation, read only for now

Inc/control.h

@@ -2,17 +2,43 @@
 #define CONTROL_H
 
 #include "stm32f4xx_hal.h"
+#include "fatfs.h"
+#include <sys/types.h>
+
+enum Type {
+	TYPE_NONE,
+	TYPE_FILE,
+	TYPE_DIR
+};
 
 typedef struct {
-	uint8_t dirty;
+	// Block and size are in blocks of 128
-	uint8_t action;
+	uint32_t start;
+	uint32_t size;
+	char* filename;
+	char name[8];
+	char ext[3];
+} DiskEntry;
+
+typedef struct {
+	uint8_t entry_count;
+	uint8_t current;
+	DiskEntry entries[127];
+	uint32_t end;
+} Disk;
+
+typedef struct {
+	FATFS *fs;
+	FIL *file;
+	uint8_t command;
 	uint8_t ready;
-	uint8_t lba_1;
-	uint8_t lba_2;
-	uint8_t lba_3;
-	uint32_t lba;
 	uint32_t counter;
+	uint32_t lba;
+	uint32_t offset;
 	uint8_t* buffer;
+	unsigned int size;
+	enum Type type;
+	Disk A;
 } Storage;
 
 typedef struct {

Src/control.c

@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <string.h>
+#include <sys/types.h>
 #include "control.h"
 #include "io.h"
 #include "bsp_driver_sd.h"
@@ -19,12 +20,9 @@ extern UART_HandleTypeDef huart2;
 extern uint8_t ack[1];
 extern uint8_t nack[1];
 
-// @todo For some reason increasing SD_PAGES does not work
+#define CPM_RECORD_SIZE 128
-#define SD_PAGES 1
+#define CPM_RECODS_PER_BLOCK 128
-#define CPM_PAGE_SIZE 128
+#define CPM_BLOCK_SIZE CPM_RECORD_SIZE*CPM_RECODS_PER_BLOCK
-
-#define SD_PAGE_SIZE 512
-#define CPM_PAGES (SD_PAGE_SIZE/CPM_PAGE_SIZE*SD_PAGES)
 
 uint8_t get_device(uint16_t address) {
 	uint8_t page = address >> 12;
@@ -37,20 +35,6 @@ uint8_t get_device(uint16_t address) {
 	return 0xFF;
 }
 
-uint32_t calculate_lba() {
-	uint32_t temp = (control.storage.lba_1) + (control.storage.lba_2 << 8) + (control.storage.lba_3 << 16);
-	if (temp/CPM_PAGES != control.storage.lba/CPM_PAGES) {
-		control.storage.dirty |= 1;
-	}
-
-	/* printf("LBA [1]: %li\n\r", control.storage.lba_1); */
-	/* printf("LBA [2]: %li\n\r", control.storage.lba_2); */
-	/* printf("LBA [3]: %li\n\r", control.storage.lba_3); */
-	/* printf("LBA: %li\n\r", control.storage.lba); */
-
-	return temp;
-}
-
 void control_program_eeprom(uint8_t* data, uint16_t length) {
 	// Take control of the bus
 	send_busrq(1);
@@ -127,31 +111,100 @@ void handle_io_read() {
 		/* 	write_data(0x00); */
 		/* 	break; */
 
+		// Read byte from disk
 		case 0x08:
-			if (control.storage.ready && control.storage.action == 0x20) {
+			if (control.storage.ready && control.storage.command == 0x20) {
-				write_data(control.storage.buffer[control.storage.counter + (control.storage.lba % CPM_PAGES)*CPM_PAGE_SIZE]);
+				if (control.storage.counter < control.storage.size) {
+					write_data(control.storage.buffer[control.storage.counter]);
 					control.storage.counter++;
-
-				if (control.storage.counter >= CPM_PAGE_SIZE) {
-					control.storage.ready = 0;
-					control.storage.action = 0;
-				}
 				} else {
 					write_data(0x00);
 				}
 
+				if (control.storage.counter >= control.storage.size) {
+					control.storage.ready = 0;
+					control.storage.command = 0;
+				}
+			} else {
+				write_data(0x00);
+			}
 			break;
 
+		// Check if disk is ready
 		case 0x0f:
-			// Check if we need to read and in that case to the read
+			if (control.storage.command == 0x20 && !control.storage.ready) {
-			if (control.storage.action && !control.storage.ready) {
+				switch (control.storage.type) {
-				if (!control.storage.dirty || BSP_SD_ReadBlocks((uint32_t*)control.storage.buffer, control.storage.lba/CPM_PAGES, SD_PAGES, SD_DATATIMEOUT) == MSD_OK) {
+					case TYPE_NONE: 
-					// Indicate that we are ready to read/write
+						control.storage.size = 0;
 						control.storage.ready = 1;
-					control.storage.dirty = 0;
+						break;
+
+					case TYPE_FILE: {
+						FRESULT fr = f_lseek(control.storage.file, control.storage.offset * CPM_RECORD_SIZE);
+						if (fr) {
+							printf("File error: %i\n\r", fr);
 						} else {
-					// If we failed to read we will try again next time
+							control.storage.ready = 1;
-					/* printf("READ FAIL!\n\r"); */
+						}
+
+						fr = f_read(control.storage.file, control.storage.buffer, CPM_RECORD_SIZE, &control.storage.size);
+						if (fr) {
+							printf("File error: %i\n\r", fr);
+						} else {
+							control.storage.ready = 1;
+						}
+
+						break;
+					}
+
+					case TYPE_DIR: {
+						for (int i = 0; i < 128; i += 32) {
+							control.storage.buffer[i] = 0xe5;
+						}
+
+						for (int i = 0; i < 4; ++i) {
+							if (4*control.storage.offset + i >= control.storage.A.entry_count) {
+								break;
+							}
+
+							control.storage.buffer[32*i + 0] = 0x00;
+							for (int j = 0; j < 8; ++j) {
+								control.storage.buffer[32*i + 1 + j] = control.storage.A.entries[4*control.storage.offset + i].name[j];
+							}
+
+							for (int j = 0; j < 3; ++j) {
+								control.storage.buffer[32*i + 9 + j] = control.storage.A.entries[4*control.storage.offset + i].ext[j];
+							}
+
+							uint16_t extents = 0x00;
+							uint16_t records = control.storage.A.entries[4*control.storage.offset + i].size;
+
+							while (records >= 0x80) {
+								extents++;
+								records -= 0x80;
+							}
+
+							control.storage.buffer[32*i + 12] = extents & 0xFF; // Extent low
+							control.storage.buffer[32*i + 13] = 0x00; // Reserved 0x00
+							control.storage.buffer[32*i + 14] = (extents >> 8) & 0xFF; // Extent high
+							control.storage.buffer[32*i + 15] = records;
+
+							for (int j = 0; j < 16; ++j) {
+								control.storage.buffer[32*i + 16 + j] = 0x00;
+							}
+
+							for (int j = 0; j < (extents+1); ++j) {
+								control.storage.buffer[32*i + 16 + j*2] = control.storage.A.entries[4*control.storage.offset + i].start + j;
+								control.storage.buffer[32*i + 17 + j*2] = 0x00;
+							}
+						}
+
+						control.storage.size = 128;
+						control.storage.ready = 1;
+
+						break;
+					}
+
 				}
 			}
 
@@ -187,41 +240,88 @@ void handle_io_write() {
 			printf("%c", value);
 			break;
 
+		// Write byte to disk
 		case 0x08:
-			if (control.storage.ready && control.storage.action == 0x30) {
+			break;
-				control.storage.buffer[control.storage.counter + (control.storage.lba % CPM_PAGES)*CPM_PAGE_SIZE] = value;
-				control.storage.counter++;
 
-				if (control.storage.counter >= CPM_PAGE_SIZE) {
+		case 0x0b: {
-					// @todo We need to figure out some way to actually prevent write fails from occuring
+			uint32_t temp = control.storage.lba & 0xFFFF00;
-					if (BSP_SD_WriteBlocks((uint32_t*)control.storage.buffer, control.storage.lba/CPM_PAGES, SD_PAGES, SD_DATATIMEOUT) != MSD_OK) {
+			control.storage.lba = temp + value;
-						printf("WRITE FAIL!!\n\r");
+			break;
 		}
+
+		case 0x0c: {
+			uint32_t temp = control.storage.lba & 0xFF00FF;
+			control.storage.lba = temp + (value << 8);
+			break;
+		}
+
+		case 0x0d: {
+			uint32_t temp = control.storage.lba & 0x00FFFF;
+			control.storage.lba = temp + (value << 16);
+			break;
+		}
+
+		// Receive disk command
+		case 0x0f: {
 			control.storage.ready = 0;
-					control.storage.action = 0;
-				}
-			}
-			break;
-
-		case 0x0b:
-			control.storage.lba_1 = value;
-			break;
-
-		case 0x0c:
-			control.storage.lba_2 = value;
-			break;
-
-		case 0x0d:
-			control.storage.lba_3 = value;
-			break;
-
-		case 0x0f:
-			if (value == 0x20 || value == 0x30) {
-				control.storage.lba = calculate_lba();
-				control.storage.action = value;
 			control.storage.counter = 0;
+			control.storage.command = value;
+			FRESULT fr = 0;
+
+			if (control.storage.type == TYPE_FILE) {
+				fr = f_close(control.storage.file);
+				if (fr) {
+					printf("File error: %i\n\r", fr);
+				}
+			}
+
+			// @todo We need to make it easier to set this up
+			if (control.storage.lba == 0) {
+				// bootloader
+				control.storage.offset = control.storage.lba - 0;
+				fr = f_open(control.storage.file, "0:loader.bin", FA_READ);
+				control.storage.type = TYPE_FILE;
+			} else if (control.storage.lba >= 1 && control.storage.lba < 45) {
+				// cpm
+				control.storage.offset = control.storage.lba - 1;
+				fr = f_open(control.storage.file, "0:cpm22.bin", FA_READ);
+				control.storage.type = TYPE_FILE;
+			} else if (control.storage.lba >= 45 && control.storage.lba < 51) {
+				// bios
+				control.storage.offset = control.storage.lba - 45;
+				fr = f_open(control.storage.file, "0:bios.bin", FA_READ);
+				control.storage.type = TYPE_FILE;
+			} else if (control.storage.lba >= 256 && control.storage.lba < (256+32)) {
+				// @todo Max out at end of disk A
+				control.storage.offset = control.storage.lba - 256;
+				control.storage.type = TYPE_DIR;
+			} else if (control.storage.lba > (256+32)) {
+				control.storage.type = TYPE_NONE;
+
+				for (uint8_t i = 0; i < control.storage.A.entry_count; ++i) {
+					if (control.storage.lba >= (control.storage.A.entries[i].start-1)*CPM_RECODS_PER_BLOCK+384 && control.storage.lba < ((control.storage.A.entries[i].start-1)*CPM_RECODS_PER_BLOCK+384 + control.storage.A.entries[i].size)) {
+						control.storage.offset = control.storage.lba - (control.storage.A.entries[i].start-1)*CPM_RECODS_PER_BLOCK - 384;
+
+						char buf[128];
+						snprintf(buf, 128, "0:A/%s", control.storage.A.entries[i].filename);
+						fr = f_open(control.storage.file, buf, FA_READ);
+
+						control.storage.type = TYPE_FILE;
+						break;
+					}
+				}
+			} else {
+				// Empty
+				printf("Unknown %li\n\r", control.storage.lba);
+				control.storage.type = TYPE_NONE;
+			}
+
+			if (fr) {
+				printf("File error: %i\n\r", fr);
 			}
 			break;
+		}
 
 		default:
 			printf("IO Write: %.2X @ %.2X\n\r", value, address);
@@ -266,9 +366,88 @@ void control_cycle() {
 // @todo Properly reset everything
 void control_reset() {
 	free(control.storage.buffer);
-	Control temp = {0, {1, 0, 0, 0, 0, 0, 0, 0, NULL}};
+
+	// @todo Pretty sure this is not actually correct,
+	// since the pointer is always not NULL once we malloc,
+	// even if we do not have a file open/disk mounted
+	if (control.storage.file) {
+		f_close(control.storage.file);
+		free(control.storage.file);
+	}
+	if (control.storage.fs) {
+		f_mount(0, "0:", 0);
+		free(control.storage.fs);
+	}
+
+	Control temp = {0, {NULL, NULL, 0, 0, 0, 0, 0, NULL, 0, TYPE_NONE, {0}}};
 	control = temp;
-	control.storage.buffer = (uint8_t*)malloc(SD_PAGES*SD_PAGE_SIZE);
+
+	control.storage.buffer = (uint8_t*)malloc(CPM_RECORD_SIZE);
+
+	control.storage.fs = (FATFS*)malloc(sizeof(FATFS));
+	control.storage.file = (FIL*)malloc(sizeof(FIL));
+	FRESULT fr = f_mount(control.storage.fs, "0:", 0);
+	if (fr) {
+		printf("File error: %i\n\r", fr);
+	}
+
+	DIR dir;
+	FILINFO fno;
+	fr = f_opendir(&dir, "0:A");
+	control.storage.A.end = 1;
+	if (fr == FR_OK) {
+		for (;;) {
+			fr = f_readdir(&dir, &fno);
+			if (fr != FR_OK || fno.fname[0] == 0) {
+				break;
+			}
+
+			if (!(fno.fattrib & AM_DIR)) {
+				uint8_t index = control.storage.A.entry_count;
+				control.storage.A.entries[index].start = control.storage.A.end;
+
+				// Calculate the number of records
+				uint32_t size = (fno.fsize + CPM_RECORD_SIZE - 1) / CPM_RECORD_SIZE;
+
+				// Increment the end by the number of blocks
+				control.storage.A.end += (size + CPM_RECODS_PER_BLOCK) / CPM_RECODS_PER_BLOCK;
+
+				// Store the size in the number of records
+				control.storage.A.entries[index].size = size;
+
+				control.storage.A.entries[index].filename = strdup(fno.fname);
+				
+				uint8_t name_len = 9;
+				for (uint8_t i = 0; i < 8; ++i) {
+					char c = ' ';
+
+					if (name_len == 9 && fno.fname[i] != '.') {
+						c = fno.fname[i];
+					} else if (name_len == 9){
+						name_len = i+1;
+					}
+
+					control.storage.A.entries[index].name[i] = c;
+				}
+
+				uint8_t done = 0;
+				for (uint8_t i = 0; i < 3; ++i) {
+					char c = ' ';
+					
+					if (!done && fno.fname[name_len+i] != 0) {
+						c = fno.fname[name_len+i];
+					} else {
+						done = 1;
+					}
+
+					control.storage.A.entries[index].ext[i] = c;
+				}
+
+				control.storage.A.entry_count++;
+
+			}
+		}
+	}
 
 	set_reset(1);
 	for (int i = 0; i <= 10; ++i) {

Src/main.c

@@ -19,7 +19,6 @@
 /* USER CODE END Header */
 /* Includes ------------------------------------------------------------------*/
 #include "main.h"
-#include "fatfs.h"
 #include "usb_device.h"
 
 /* Private includes ----------------------------------------------------------*/

Src/sd_diskio.c

@@ -49,7 +49,7 @@
  * BSP_SD_Init() elsewhere in the application.
  */
 /* USER CODE BEGIN disableSDInit */
-/* #define DISABLE_SD_INIT */
+#define DISABLE_SD_INIT
 /* USER CODE END disableSDInit */
 
 /* Private variables ---------------------------------------------------------*/