| 1 | |
| 2 | * This file is subject to the terms and conditions of the GNU General Public
|
| 3 | * License. See the file "COPYING" in the main directory of this archive
|
| 4 | * for more details.
|
| 5 | *
|
| 6 | * Copyright (C) 2005 Thiemo Seufer
|
| 7 | * Copyright (C) 2005 MIPS Technologies, Inc. All rights reserved.
|
| 8 | * Author: Maciej W. Rozycki <[email protected]>
|
| 9 |
|
| 10 |
|
| 11 |
|
| 12 | #include <asm/addrspace.h>
|
| 13 | #include <asm/bug.h>
|
| 14 | #include <asm/cacheflush.h>
|
| 15 |
|
| 16 | #ifndef CKSEG2
|
| 17 | #define CKSEG2 CKSSEG
|
| 18 | #endif
|
| 19 | #ifndef TO_PHYS_MASK
|
| 20 | #define TO_PHYS_MASK -1
|
| 21 | #endif
|
| 22 |
|
| 23 | |
| 24 | * FUNC is executed in one of the uncached segments, depending on its
|
| 25 | * original address as follows:
|
| 26 | *
|
| 27 | * 1. If the original address is in CKSEG0 or CKSEG1, then the uncached
|
| 28 | * segment used is CKSEG1.
|
| 29 | * 2. If the original address is in XKPHYS, then the uncached segment
|
| 30 | * used is XKPHYS(2).
|
| 31 | * 3. Otherwise it's a bug.
|
| 32 | *
|
| 33 | * The same remapping is done with the stack pointer. Stack handling
|
| 34 | * works because we don't handle stack arguments or more complex return
|
| 35 | * values, so we can avoid sharing the same stack area between a cached
|
| 36 | * and the uncached mode.
|
| 37 |
|
| 38 | unsigned long run_uncached(void *func)
|
| 39 | {
|
| 40 | register long ret __asm__("$2");
|
| 41 | long lfunc = (long)func, ufunc;
|
| 42 | long usp;
|
| 43 | long sp;
|
| 44 |
|
| 45 | __asm__("move %0, $sp" : "=r" (sp));
|
| 46 |
|
| 47 | if (sp >= (long)CKSEG0 && sp < (long)CKSEG2)
|
| 48 | usp = CKSEG1ADDR(sp);
|
| 49 | #ifdef CONFIG_64BIT
|
| 50 | else if ((long long)sp >= (long long)PHYS_TO_XKPHYS(0, 0) &&
|
| 51 | (long long)sp < (long long)PHYS_TO_XKPHYS(8, 0))
|
| 52 | usp = PHYS_TO_XKPHYS(K_CALG_UNCACHED,
|
| 53 | XKPHYS_TO_PHYS((long long)sp));
|
| 54 | #endif
|
| 55 | else {
|
| 56 | BUG();
|
| 57 | usp = sp;
|
| 58 | }
|
| 59 | if (lfunc >= (long)CKSEG0 && lfunc < (long)CKSEG2)
|
| 60 | ufunc = CKSEG1ADDR(lfunc);
|
| 61 | #ifdef CONFIG_64BIT
|
| 62 | else if ((long long)lfunc >= (long long)PHYS_TO_XKPHYS(0, 0) &&
|
| 63 | (long long)lfunc < (long long)PHYS_TO_XKPHYS(8, 0))
|
| 64 | ufunc = PHYS_TO_XKPHYS(K_CALG_UNCACHED,
|
| 65 | XKPHYS_TO_PHYS((long long)lfunc));
|
| 66 | #endif
|
| 67 | else {
|
| 68 | BUG();
|
| 69 | ufunc = lfunc;
|
| 70 | }
|
| 71 |
|
| 72 | __asm__ __volatile__ (
|
| 73 | " move $16, $sp\n"
|
| 74 | " move $sp, %1\n"
|
| 75 | " jalr %2\n"
|
| 76 | " move $sp, $16"
|
| 77 | : "=r" (ret)
|
| 78 | : "r" (usp), "r" (ufunc)
|
| 79 | : "$16", "$31");
|
| 80 |
|
| 81 | return ret;
|
| 82 | }
|