From: zippel@fh-brandenburg.de (Roman Zippel) Subject: L68K: Illegal Instruction Error To: linux-m68k@phil.uni-sb.de Date: Mon, 23 Jun 1997 15:15:07 +0200 (MET DST) Sender: owner-linux-m68k@phil.uni-sb.de Reply-To: linux-m68k@phil.uni-sb.de Hi, I hopefully found the bug in sys_cacheflush. One major bug is cache_flush_040, virt_to_phys_040 returns a pointer to the page not the physical address. But both functions had rounding problems so that not always everything is flushed. Below is a patch that hopefully fixes this. I didn't test it with the kernel (only compiled it), I only tested the functions in a test program, so that I don't know if it really fixes the problem. Roman PS: This mail should already be sent thursday, but our network connection was broken. :-( --- arch/m68k/kernel/sys_m68k.c.old Thu Jun 19 02:01:55 1997 +++ arch/m68k/kernel/sys_m68k.c Thu Jun 19 12:23:50 1997 @@ -205,11 +205,10 @@ return -ENOSYS; } -/* Convert virtual address VADDR to physical address PADDR, recording - in VALID whether the virtual address is actually mapped. */ -#define virt_to_phys_040(vaddr, paddr, valid) \ -{ \ - unsigned long _mmusr; \ +/* Convert virtual address VADDR to physical address PADDR */ +#define virt_to_phys_040(vaddr) \ +({ \ + unsigned long _mmusr, _paddr; \ \ __asm__ __volatile__ (".chip 68040\n\t" \ "ptestr (%1)\n\t" \ @@ -217,20 +216,14 @@ ".chip 68k" \ : "=r" (_mmusr) \ : "a" (vaddr)); \ - if (!(_mmusr & MMU_R_040)) \ - (valid) = 0; \ - else \ - { \ - (valid) = 1; \ - (paddr) = _mmusr & PAGE_MASK; \ - } \ -} + _paddr = (_mmusr & MMU_R_040) ? (_mmusr & PAGE_MASK) : 0; \ + _paddr; \ +}) static inline int cache_flush_040 (unsigned long addr, int scope, int cache, unsigned long len) { - unsigned long paddr; - int valid; + unsigned long paddr, i; switch (scope) { @@ -261,19 +254,31 @@ break; case FLUSH_SCOPE_LINE: - len >>= 4; /* Find the physical address of the first mapped page in the address range. */ - for (;;) - { - virt_to_phys_040 (addr, paddr, valid); - if (valid) - break; - if (len <= PAGE_SIZE / 16) - return 0; - len -= (PAGE_SIZE - (addr & PAGE_MASK)) / 16; - addr = (addr + PAGE_SIZE) & PAGE_MASK; - } + if ((paddr = virt_to_phys_040(addr))) { + paddr += addr & ~(PAGE_MASK | 15); + len = (len + (addr & 15) + 15) >> 4; + } else { + unsigned long tmp = PAGE_SIZE - (addr & ~PAGE_MASK); + + if (len <= tmp) + return 0; + addr += tmp; + len -= tmp; + tmp = PAGE_SIZE; + for (;;) + { + if ((paddr = virt_to_phys_040(addr))) + break; + if (len <= tmp) + return 0; + addr += tmp; + len -= tmp; + } + len = (len + 15) >> 4; + } + i = (PAGE_SIZE - (paddr & ~PAGE_MASK)) >> 4; while (len--) { switch (cache) @@ -301,36 +306,33 @@ : : "a" (paddr)); break; } - addr += 16; - if (len) + if (!--i && len) { - if ((addr & (PAGE_SIZE-1)) < 16) + addr += PAGE_SIZE; + i = PAGE_SIZE / 16; + /* Recompute physical address when crossing a page + boundary. */ + for (;;) { - /* Recompute physical address when crossing a page - boundary. */ - for (;;) - { - virt_to_phys_040 (addr, paddr, valid); - if (valid) - break; - if (len <= PAGE_SIZE / 16) - return 0; - len -= (PAGE_SIZE - (addr & PAGE_MASK)) / 16; - addr = (addr + PAGE_SIZE) & PAGE_MASK; - } + if ((paddr = virt_to_phys_040(addr))) + break; + if (len <= i) + return 0; + len -= i; + addr += PAGE_SIZE; } - else - paddr += 16; } + else + paddr += 16; } break; default: case FLUSH_SCOPE_PAGE: + len += (addr & ~PAGE_MASK) + (PAGE_SIZE - 1); for (len >>= PAGE_SHIFT; len--; addr += PAGE_SIZE) { - virt_to_phys_040 (addr, paddr, valid); - if (!valid) + if (!(paddr = virt_to_phys_040(addr))) continue; switch (cache) { @@ -363,21 +365,21 @@ return 0; } -#define virt_to_phys_060(vaddr, paddr, valid) \ -{ \ +#define virt_to_phys_060(vaddr) \ +({ \ + unsigned long paddr; \ __asm__ __volatile__ (".chip 68060\n\t" \ "plpar (%0)\n\t" \ ".chip 68k" \ : "=a" (paddr) \ : "0" (vaddr)); \ - (valid) = 1; /* XXX */ \ -} + (paddr); /* XXX */ \ +}) static inline int cache_flush_060 (unsigned long addr, int scope, int cache, unsigned long len) { - unsigned long paddr; - int valid; + unsigned long paddr, i; switch (scope) { @@ -407,19 +409,30 @@ break; case FLUSH_SCOPE_LINE: - len >>= 4; /* Find the physical address of the first mapped page in the address range. */ - for (;;) - { - virt_to_phys_060 (addr, paddr, valid); - if (valid) - break; - if (len <= PAGE_SIZE / 16) - return 0; - len -= (PAGE_SIZE - (addr & PAGE_MASK)) / 16; - addr = (addr + PAGE_SIZE) & PAGE_MASK; - } + len += addr & 15; + addr &= -16; + if (!(paddr = virt_to_phys_060(addr))) { + unsigned long tmp = PAGE_SIZE - (addr & ~PAGE_MASK); + + if (len <= tmp) + return 0; + addr += tmp; + len -= tmp; + tmp = PAGE_SIZE; + for (;;) + { + if ((paddr = virt_to_phys_060(addr))) + break; + if (len <= tmp) + return 0; + addr += tmp; + len -= tmp; + } + } + len = (len + 15) >> 4; + i = (PAGE_SIZE - (paddr & ~PAGE_MASK)) >> 4; while (len--) { switch (cache) @@ -447,36 +460,33 @@ : : "a" (paddr)); break; } - addr += 16; - if (len) + if (!--i && len) { - if ((addr & (PAGE_SIZE-1)) < 16) - { - /* Recompute the physical address when crossing a - page boundary. */ - for (;;) - { - virt_to_phys_060 (addr, paddr, valid); - if (valid) - break; - if (len <= PAGE_SIZE / 16) - return 0; - len -= (PAGE_SIZE - (addr & PAGE_MASK)) / 16; - addr = (addr + PAGE_SIZE) & PAGE_MASK; - } - } - else - paddr += 16; + addr += PAGE_SIZE; + i = PAGE_SIZE / 16; + /* Recompute physical address when crossing a page + boundary. */ + for (;;) + { + if ((paddr = virt_to_phys_060(addr))) + break; + if (len <= i) + return 0; + len -= i; + addr += PAGE_SIZE; + } } + else + paddr += 16; } break; default: case FLUSH_SCOPE_PAGE: + len += (addr & ~PAGE_MASK) + (PAGE_SIZE - 1); for (len >>= PAGE_SHIFT; len--; addr += PAGE_SIZE) { - virt_to_phys_060 (addr, paddr, valid); - if (!valid) + if (!(paddr = virt_to_phys_060(addr))) continue; switch (cache) {