Sat, 17 Nov 2012 19:18:29 +0000
add HDD support + fixes
Patch-Author: Andrew Warkentin <andreww591!gmail>
Patch-Message-ID: <50A772FC.8020009@gmail.com>
I have added floppy write support, full hard disk emulation, and proper handling of DMA page faults to FreeBee. I also fixed the floppy step commands, changed the "force interrupt" floppy command to generate a type 1 status, and changed the DMA address counter to reset to 3fff when a transfer completes (which is what Unix seems to expect - without it, the kernel says that the floppy isn't ready). The floppy, hard disk, and DMA page fault tests all pass. Initializing hard disks and floppies also works (the geometry for both is still fixed by the size of the image, though, and format commands only appear to succeed, but they don't modify the image). Unix still doesn't run, though (it hangs after reading some sectors from the floppy).
| philpem@40 | 1 | #ifndef _MEMORY_H |
| philpem@40 | 2 | #define _MEMORY_H |
| philpem@40 | 3 | |
| philpem@40 | 4 | /*********************************** |
| philpem@40 | 5 | * Array read/write utility macros |
| philpem@40 | 6 | * "Don't Repeat Yourself" :) |
| philpem@40 | 7 | ***********************************/ |
| philpem@40 | 8 | |
| philpem@40 | 9 | /// Array read, 32-bit |
| philpem@40 | 10 | #define RD32(array, address, andmask) \ |
| philpem@40 | 11 | (((uint32_t)array[(address + 0) & (andmask)] << 24) | \ |
| philpem@40 | 12 | ((uint32_t)array[(address + 1) & (andmask)] << 16) | \ |
| philpem@40 | 13 | ((uint32_t)array[(address + 2) & (andmask)] << 8) | \ |
| philpem@40 | 14 | ((uint32_t)array[(address + 3) & (andmask)])) |
| philpem@40 | 15 | |
| philpem@40 | 16 | /// Array read, 16-bit |
| philpem@40 | 17 | #define RD16(array, address, andmask) \ |
| philpem@40 | 18 | (((uint32_t)array[(address + 0) & (andmask)] << 8) | \ |
| philpem@40 | 19 | ((uint32_t)array[(address + 1) & (andmask)])) |
| philpem@40 | 20 | |
| philpem@40 | 21 | /// Array read, 8-bit |
| philpem@40 | 22 | #define RD8(array, address, andmask) \ |
| philpem@40 | 23 | ((uint32_t)array[(address + 0) & (andmask)]) |
| philpem@40 | 24 | |
| philpem@40 | 25 | /// Array write, 32-bit |
| philpem@70 | 26 | #define WR32(array, address, andmask, value) do { \ |
| philpem@40 | 27 | array[(address + 0) & (andmask)] = (value >> 24) & 0xff; \ |
| philpem@40 | 28 | array[(address + 1) & (andmask)] = (value >> 16) & 0xff; \ |
| philpem@40 | 29 | array[(address + 2) & (andmask)] = (value >> 8) & 0xff; \ |
| philpem@40 | 30 | array[(address + 3) & (andmask)] = value & 0xff; \ |
| philpem@70 | 31 | } while (0) |
| philpem@40 | 32 | |
| philpem@40 | 33 | /// Array write, 16-bit |
| philpem@70 | 34 | #define WR16(array, address, andmask, value) do { \ |
| philpem@40 | 35 | array[(address + 0) & (andmask)] = (value >> 8) & 0xff; \ |
| philpem@40 | 36 | array[(address + 1) & (andmask)] = value & 0xff; \ |
| philpem@70 | 37 | } while (0) |
| philpem@40 | 38 | |
| philpem@40 | 39 | /// Array write, 8-bit |
| philpem@70 | 40 | #define WR8(array, address, andmask, value) do { \ |
| philpem@70 | 41 | array[(address + 0) & (andmask)] = value & 0xff; \ |
| philpem@70 | 42 | } while (0) |
| philpem@40 | 43 | |
| philpem@40 | 44 | /****************** |
| philpem@40 | 45 | * Memory mapping |
| philpem@40 | 46 | ******************/ |
| philpem@40 | 47 | |
| philpem@40 | 48 | typedef enum { |
| philpem@40 | 49 | MEM_ALLOWED = 0, |
| philpem@40 | 50 | MEM_PAGEFAULT, // Page fault -- page not present |
| philpem@40 | 51 | MEM_PAGE_NO_WE, // Page not write enabled |
| philpem@40 | 52 | MEM_KERNEL, // User attempted to access kernel memory |
| philpem@40 | 53 | MEM_UIE // User Nonmemory Location Access |
| philpem@40 | 54 | } MEM_STATUS; |
| philpem@40 | 55 | |
| philpem@40 | 56 | /** |
| philpem@40 | 57 | * @brief Check memory access permissions for a given address. |
| philpem@40 | 58 | * @param addr Address. |
| philpem@40 | 59 | * @param writing true if writing to memory, false if reading. |
| philpem@40 | 60 | * @return One of the MEM_STATUS constants, specifying whether the access is |
| philpem@40 | 61 | * permitted, or what error occurred. |
| philpem@40 | 62 | */ |
| philpem@40 | 63 | MEM_STATUS checkMemoryAccess(uint32_t addr, bool writing); |
| philpem@40 | 64 | |
| philpem@40 | 65 | /** |
| philpem@40 | 66 | * @brief Map a CPU memory address into physical memory space. |
| philpem@40 | 67 | * @param addr Address. |
| philpem@40 | 68 | * @param writing true if writing to memory, false if reading. |
| philpem@40 | 69 | * @return Address, remapped into physical memory. |
| philpem@40 | 70 | */ |
| philpem@40 | 71 | uint32_t mapAddr(uint32_t addr, bool writing); |
| philpem@40 | 72 | |
| philpem@112 | 73 | /** |
| philpem@112 | 74 | * @brief Check access flags for a DMA transfer and trigger an exception if |
| philpem@112 | 75 | * the access is not permitted |
| philpem@112 | 76 | * @param reading true if reading from memory, false if writing |
| philpem@112 | 77 | * @return true if the access is permitted, false if not |
| philpem@112 | 78 | */ |
| philpem@112 | 79 | bool access_check_dma(int reading); |
| philpem@112 | 80 | |
| philpem@40 | 81 | #endif |