/* ScummVM - Scumm Interpreter * Copyright (C) 2001 Ludvig Strigeus * Copyright (C) 2001-2006 The ScummVM project * Copyright (C) 2005-2006 John Willis (Portions of the GP2X Backend) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * $URL$ * $Id$ * */ /* * GP2X: Memory tweaking stuff. * */ #include #include #include #include #include #include #include #include #include "gp2x-mem.h" void InitRam (void) { if(!gp2x_dev) { gp2x_dev = open("/dev/mem", O_RDWR); gp2x_ram = (unsigned short *)mmap(0, 0x10000, 3, 1, gp2x_dev, 0x03000000); gp2x_memregs = (unsigned short *)mmap(0, 0x10000, 3, 1, gp2x_dev, 0xc0000000); } } void CloseRam (void) { if(gp2x_dev) close(gp2x_dev); } /* ****** [BEGIN] Squidge's MMU hack code ****** */ int myuname(char *buffer) { asm volatile ("swi #0x90007a"); } void DecodeCoarse (unsigned int indx, unsigned int sa) { unsigned int cpt[256]; unsigned int temp; unsigned int i = 0; unsigned int wb = 0; sa &= 0xfffffc00; indx *= 1048576; //printf (" > %08X\n", sa); //printf ("%d\n", lseek (gp2x_dev, sa, SEEK_SET); memset (cpt, 0, 256*4); temp = read (gp2x_dev, cpt, 256*4); //printf ("%d\n", temp); if (temp != 256*4) { printf (" # Bad read\n"); return; } //printf ("%08X %08X %08X %08X\n", cpt[0], cpt[4], cpt[8], cpt[12]); for (i = 0; i < 256; i ++) { if (cpt[i]) { switch (cpt[i] & 3) { case 0: //printf (" -- [%08X] Invalid --\n", cpt[i]); break; case 1: /* printf (" VA: %08X PA: %08X - %08X A: %d %d %d %d D: %d C: %d B: %d\n", indx, cpt[i] & 0xFFFF0000, (cpt[i] & 0xFFFF0000) | 0xFFFF, (cpt[i] >> 10) & 3, (cpt[i] >> 8) & 3, (cpt[i] >> 6) & 3, (cpt[i] >> 4) & 3, dom, (cpt[i] >> 3) & 1, (cpt[i] >> 2) & 1); */ break; case 2: //a=((cpt[i] & 0xff000000)>>24); /*printf (" VA: %08X PA: %08X - %08X A: %d %d %d %d D: %d C: %d B: %d\n", indx, cpt[i] & 0xfffff000, (cpt[i] & 0xfffff000) | 0xFFF, (cpt[i] >> 10) & 3, (cpt[i] >> 8) & 3, (cpt[i] >> 6) & 3, (cpt[i] >> 4) & 3, dom, (cpt[i] >> 3) & 1, (cpt[i] >> 2) & 1); */ // This is where we look for any virtual addresses that map to physical address 0x03000000 and // alter the cachable and bufferable bits... if (((cpt[i] & 0xff000000) == 0x02000000) ) { //printf("SOUND c and b bits not set, overwriting\n"); if((cpt[i] & 12)==0) { cpt[i] |= 0xFFC; wb++; } } //if ((a>=0x31 && a<=0x36) && ((cpt[i] & 12)==0)) if (((cpt[i] & 0xff000000) == 0x03000000) ) { //printf("SDL c and b bits not set, overwriting\n"); if((cpt[i] & 12)==0) { cpt[i] |= 0xFFC; wb++; } } break; case 3: //printf (" -- [%08X/%d] Unsupported --\n", cpt[i],cpt[i] & 3); break; default: //printf (" -- [%08X/%d] Unknown --\n", cpt[i], cpt[i] & 3); break; } } indx += 4096; } //printf ("%08X %08X %08X %08X\n", cpt[0], cpt[4], cpt[8], cpt[12]); if (wb) { //printf("Hacking cpt\n"); lseek (gp2x_dev, sa, SEEK_SET); temp = write (gp2x_dev, cpt, 256*4); printf("%d bytes written, %s\n", temp, temp == 1024 ? "yay!" : "oh fooble :(!"); } } void dumppgtable (unsigned int ttb) { unsigned int pgtable[4096]; char *desctypes[] = {"Invalid", "Coarse", "Section", "Fine"}; memset (pgtable, 0, 4096*4); lseek (gp2x_dev, ttb, SEEK_SET); read (gp2x_dev, pgtable, 4096*4); int i; for (i = 0; i < 4096; i ++) { int temp; if (pgtable[i]) { //printf ("Indx: %d VA: %08X Type: %d [%s] \n", i, i * 1048576, pgtable[i] & 3, desctypes[pgtable[i]&3]); switch (pgtable[i]&3) { case 0: //printf (" -- Invalid --\n"); break; case 1: DecodeCoarse(i, pgtable[i]); break; case 2: temp = pgtable[i] & 0xFFF00000; //printf (" PA: %08X - %08X A: %d D: %d C: %d B: %d\n", temp, temp | 0xFFFFF, // (pgtable[i] >> 10) & 3, (pgtable[i] >> 5) & 15, (pgtable[i] >> 3) & 1, // (pgtable[i] >> 2) & 1); break; case 3: printf (" -- Unsupported! --\n"); break; } } } } int hackpgtable (void) { unsigned int oldc1, oldc2, oldc3, oldc4; unsigned int newc1 = 0xee120f10, newc2 = 0xe12fff1e; unsigned int ttb, ttx; int a=0;int try=0; // We need to execute a "MRC p15, 0, r0, c2, c0, 0", to get the pointer to the translation table base, but we can't // do this in user mode, so we have to patch the kernel to get it to run it for us in supervisor mode. We dothis // at the moment by overwriting the sys_newuname function and then calling it. lseek (gp2x_dev, 0x6ec00, SEEK_SET); // fixme: We should ask the kernel for this address rather than assuming it... read (gp2x_dev, &oldc1, 4); read (gp2x_dev, &oldc2, 4); read (gp2x_dev, &oldc3, 4); read (gp2x_dev, &oldc4, 4); printf ("0:%08X %08X - %08X %08X\n", oldc1, oldc2, newc1, newc2); printf ("point1 %d\n",a); do { lseek (gp2x_dev, 0x6ec00, SEEK_SET); a+=write (gp2x_dev, &newc1, 4); a+=write (gp2x_dev, &newc2, 4); SDL_Delay(200); try++; ttb = myuname(name); printf ("2:%08X try %d\n", ttb,try); } while (ttb==0 && try<4); lseek (gp2x_dev, 0x6ec00, SEEK_SET); a+=write (gp2x_dev, &oldc1, 4); a+=write (gp2x_dev, &oldc2, 4); printf ("2:%08X %d\n", ttb,a); if (ttb!=0) { //printf ("Restored contents\n"); // We now have the translation table base ! Walk the table looking for our allocation and hack it :) dumppgtable(ttb); // Now drain the write buffer and flush the tlb caches. Something else we can't do in user mode... unsigned int tlbc1 = 0xe3a00000; // mov r0, #0 unsigned int tlbc2 = 0xee070f9a; // mcr 15, 0, r0, cr7, cr10, 4 unsigned int tlbc3 = 0xee080f17; // mcr 15, 0, r0, cr8, cr7, 0 unsigned int tlbc4 = 0xe1a0f00e; // mov pc, lr lseek (gp2x_dev, 0x6ec00, SEEK_SET); write (gp2x_dev, &tlbc1, 4); write (gp2x_dev, &tlbc2, 4); write (gp2x_dev, &tlbc3, 4); write (gp2x_dev, &tlbc4, 4); SDL_Delay(200); ttx = myuname(name); printf ("Return from uname: %08X\n", ttx); lseek (gp2x_dev, 0x6ec00, SEEK_SET); write (gp2x_dev, &oldc1, 4); write (gp2x_dev, &oldc2, 4); write (gp2x_dev, &oldc3, 4); write (gp2x_dev, &oldc4, 4); lseek (gp2x_dev, 0x0, SEEK_SET); return 0; } lseek (gp2x_dev, 0x0, SEEK_SET); return 1; //printf ("Restored contents\n"); //printf ("Pagetable after modification!\n"); //printf ("-------------------------------\n"); //dumppgtable(ttb); } /* ****** [END] Squidge's MMU hack code ****** */ void SetClock (unsigned c) { unsigned v; unsigned mdiv,pdiv=3,scale=0; // Set ARM920t clock c *= 1000000; mdiv = (c*pdiv) / SYS_CLK_FREQ; mdiv = ((mdiv-8)<<8) & 0xff00; pdiv = ((pdiv-2)<<2) & 0xfc; scale &= 3; v = mdiv | pdiv | scale; gp2x_memregs[0x910>>1] = v; } void MMUpatch (void) { volatile unsigned int *secbuf = (unsigned int *)malloc (204800); // Squidge's MMU hack hackpgtable(); }