/* btfixup.c: Boot time code fixup and relocator, so that * we can get rid of most indirect calls to achieve single * image sun4c and srmmu kernel. * * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) */ #include <linux/kernel.h> #include <linux/init.h> #include <asm/btfixup.h> #include <asm/page.h> #include <asm/pgalloc.h> #include <asm/pgtable.h> #include <asm/oplib.h> #include <asm/system.h> #include <asm/cacheflush.h> #define BTFIXUP_OPTIMIZE_NOP #define BTFIXUP_OPTIMIZE_OTHER extern char *srmmu_name; static char version[] __initdata = "Boot time fixup v1.6. 4/Mar/98 Jakub Jelinek (jj@ultra.linux.cz). Patching kernel for "; static char str_sun4c[] __initdata = "sun4c\n"; static char str_srmmu[] __initdata = "srmmu[%s]/"; static char str_iommu[] __initdata = "iommu\n"; static char str_iounit[] __initdata = "io-unit\n"; static int visited __initdata = 0; extern unsigned int ___btfixup_start[], ___btfixup_end[], __init_begin[], __init_end[], __init_text_end[]; extern unsigned int _stext[], _end[], __start___ksymtab[], __stop___ksymtab[]; static char wrong_f[] __initdata = "Trying to set f fixup %p to invalid function %08x\n"; static char wrong_b[] __initdata = "Trying to set b fixup %p to invalid function %08x\n"; static char wrong_s[] __initdata = "Trying to set s fixup %p to invalid value %08x\n"; static char wrong_h[] __initdata = "Trying to set h fixup %p to invalid value %08x\n"; static char wrong_a[] __initdata = "Trying to set a fixup %p to invalid value %08x\n"; static char wrong[] __initdata = "Wrong address for %c fixup %p\n"; static char insn_f[] __initdata = "Fixup f %p refers to weird instructions at %p[%08x,%08x]\n"; static char insn_b[] __initdata = "Fixup b %p doesn't refer to a SETHI at %p[%08x]\n"; static char insn_s[] __initdata = "Fixup s %p doesn't refer to an OR at %p[%08x]\n"; static char insn_h[] __initdata = "Fixup h %p doesn't refer to a SETHI at %p[%08x]\n"; static char insn_a[] __initdata = "Fixup a %p doesn't refer to a SETHI nor OR at %p[%08x]\n"; static char insn_i[] __initdata = "Fixup i %p doesn't refer to a valid instruction at %p[%08x]\n"; static char fca_und[] __initdata = "flush_cache_all undefined in btfixup()\n"; static char wrong_setaddr[] __initdata = "Garbled CALL/INT patch at %p[%08x,%08x,%08x]=%08x\n"; #ifdef BTFIXUP_OPTIMIZE_OTHER static void __init set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value) { if (!fmangled) *addr = value; else { unsigned int *q = (unsigned int *)q1; if (*addr == 0x01000000) { /* Noped */ *q = value; } else if (addr[-1] == *q) { /* Moved */ addr[-1] = value; *q = value; } else { prom_printf(wrong_setaddr, addr-1, addr[-1], *addr, *q, value); prom_halt(); } } } #else static inline void set_addr(unsigned int *addr, unsigned int q1, int fmangled, unsigned int value) { *addr = value; } #endif void __init btfixup(void) { unsigned int *p, *q; int type, count; unsigned insn; unsigned *addr; int fmangled = 0; void (*flush_cacheall)(void); if (!visited) { visited++; printk(version); if (ARCH_SUN4C) printk(str_sun4c); else { printk(str_srmmu, srmmu_name); if (sparc_cpu_model == sun4d) printk(str_iounit); else printk(str_iommu); } } for (p = ___btfixup_start; p < ___btfixup_end; ) { count = p[2]; q = p + 3; switch (type = *(unsigned char *)p) { case 'f': count = p[3]; q = p + 4; if (((p[0] & 1) || p[1]) && ((p[1] & 3) || (unsigned *)(p[1]) < _stext || (unsigned *)(p[1]) >= _end)) { prom_printf(wrong_f, p, p[1]); prom_halt(); } break; case 'b': if (p[1] < (unsigned long)__init_begin || p[1] >= (unsigned long)__init_text_end || (p[1] & 3)) { prom_printf(wrong_b, p, p[1]); prom_halt(); } break; case 's': if (p[1] + 0x1000 >= 0x2000) { prom_printf(wrong_s, p, p[1]); prom_halt(); } break; case 'h': if (p[1] & 0x3ff) { prom_printf(wrong_h, p, p[1]); prom_halt(); } break; case 'a': if (p[1] + 0x1000 >= 0x2000 && (p[1] & 0x3ff)) { prom_printf(wrong_a, p, p[1]); prom_halt(); } break; } if (p[0] & 1) { p[0] &= ~1; while (count) { fmangled = 0; addr = (unsigned *)*q; if (addr < _stext || addr >= _end) { prom_printf(wrong, type, p); prom_halt(); } insn = *addr; #ifdef BTFIXUP_OPTIMIZE_OTHER if (type != 'f' && q[1]) { insn = *(unsigned int *)q[1]; if (!insn || insn == 1) insn = *addr; else fmangled = 1; } #endif switch (type) { case 'f': /* CALL */ if (addr >= __start___ksymtab && addr < __stop___ksymtab) { *addr = p[1]; break; } else if (!q[1]) { if ((insn & 0xc1c00000) == 0x01000000) { /* SETHI */ *addr = (insn & 0xffc00000) | (p[1] >> 10); break; } else if ((insn & 0xc1f82000) == 0x80102000) { /* OR X, %LO(i), Y */ *addr = (insn & 0xffffe000) | (p[1] & 0x3ff); break; } else if ((insn & 0xc0000000) != 0x40000000) { /* !CALL */ bad_f: prom_printf(insn_f, p, addr, insn, addr[1]); prom_halt(); } } else if (q[1] != 1) addr[1] = q[1]; if (p[2] == BTFIXUPCALL_NORM) { norm_f: *addr = 0x40000000 | ((p[1] - (unsigned)addr) >> 2); q[1] = 0; break; } #ifndef BTFIXUP_OPTIMIZE_NOP goto norm_f; #else if (!(addr[1] & 0x80000000)) { if ((addr[1] & 0xc1c00000) != 0x01000000) /* !SETHI */ goto bad_f; /* CALL, Bicc, FBfcc, CBccc are weird in delay slot, aren't they? */ } else { if ((addr[1] & 0x01800000) == 0x01800000) { if ((addr[1] & 0x01f80000) == 0x01e80000) { /* RESTORE */ goto norm_f; /* It is dangerous to patch that */ } goto bad_f; } if ((addr[1] & 0xffffe003) == 0x9e03e000) { /* ADD %O7, XX, %o7 */ int displac = (addr[1] << 19); displac = (displac >> 21) + 2; *addr = (0x10800000) + (displac & 0x3fffff); q[1] = addr[1]; addr[1] = p[2]; break; } if ((addr[1] & 0x201f) == 0x200f || (addr[1] & 0x7c000) == 0x3c000) goto norm_f; /* Someone is playing bad tricks with us: rs1 or rs2 is o7 */ if ((addr[1] & 0x3e000000) == 0x1e000000) goto norm_f; /* rd is %o7. We'd better take care. */ } if (p[2] == BTFIXUPCALL_NOP) { *addr = 0x01000000; q[1] = 1; break; } #ifndef BTFIXUP_OPTIMIZE_OTHER goto norm_f; #else if (addr[1] == 0x01000000) { /* NOP in the delay slot */ q[1] = addr[1]; *addr = p[2]; break; } if ((addr[1] & 0xc0000000) != 0xc0000000) { /* Not a memory operation */ if ((addr[1] & 0x30000000) == 0x10000000) { /* Ok, non-memory op with rd %oX */ if ((addr[1] & 0x3e000000) == 0x1c000000) goto bad_f; /* Aiee. Someone is playing strange %sp tricks */ if ((addr[1] & 0x3e000000) > 0x12000000 || ((addr[1] & 0x3e000000) == 0x12000000 && p[2] != BTFIXUPCALL_STO1O0 && p[2] != BTFIXUPCALL_SWAPO0O1) || ((p[2] & 0xffffe000) == BTFIXUPCALL_RETINT(0))) { /* Nobody uses the result. We can nop it out. */ *addr = p[2]; q[1] = addr[1]; addr[1] = 0x01000000; break; } if ((addr[1] & 0xf1ffffe0) == 0x90100000) { /* MOV %reg, %Ox */ if ((addr[1] & 0x3e000000) == 0x10000000 && (p[2] & 0x7c000) == 0x20000) { /* Ok, it is call xx; mov reg, %o0 and call optimizes to doing something on %o0. Patch the patch. */ *addr = (p[2] & ~0x7c000) | ((addr[1] & 0x1f) << 14); q[1] = addr[1]; addr[1] = 0x01000000; break; } if ((addr[1] & 0x3e000000) == 0x12000000 && p[2] == BTFIXUPCALL_STO1O0) { *addr = (p[2] & ~0x3e000000) | ((addr[1] & 0x1f) << 25); q[1] = addr[1]; addr[1] = 0x01000000; break; } } } } *addr = addr[1]; q[1] = addr[1]; addr[1] = p[2]; break; #endif /* BTFIXUP_OPTIMIZE_OTHER */ #endif /* BTFIXUP_OPTIMIZE_NOP */ case 'b': /* BLACKBOX */ /* Has to be sethi i, xx */ if ((insn & 0xc1c00000) != 0x01000000) { prom_printf(insn_b, p, addr, insn); prom_halt(); } else { void (*do_fixup)(unsigned *); do_fixup = (void (*)(unsigned *))p[1]; do_fixup(addr); } break; case 's': /* SIMM13 */ /* Has to be or %g0, i, xx */ if ((insn & 0xc1ffe000) != 0x80102000) { prom_printf(insn_s, p, addr, insn); prom_halt(); } set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x1fff)); break; case 'h': /* SETHI */ /* Has to be sethi i, xx */ if ((insn & 0xc1c00000) != 0x01000000) { prom_printf(insn_h, p, addr, insn); prom_halt(); } set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10)); break; case 'a': /* HALF */ /* Has to be sethi i, xx or or %g0, i, xx */ if ((insn & 0xc1c00000) != 0x01000000 && (insn & 0xc1ffe000) != 0x80102000) { prom_printf(insn_a, p, addr, insn); prom_halt(); } if (p[1] & 0x3ff) set_addr(addr, q[1], fmangled, (insn & 0x3e000000) | 0x80102000 | (p[1] & 0x1fff)); else set_addr(addr, q[1], fmangled, (insn & 0x3e000000) | 0x01000000 | (p[1] >> 10)); break; case 'i': /* INT */ if ((insn & 0xc1c00000) == 0x01000000) /* %HI */ set_addr(addr, q[1], fmangled, (insn & 0xffc00000) | (p[1] >> 10)); else if ((insn & 0x80002000) == 0x80002000) /* %LO */ set_addr(addr, q[1], fmangled, (insn & 0xffffe000) | (p[1] & 0x3ff)); else { prom_printf(insn_i, p, addr, insn); prom_halt(); } break; } count -= 2; q += 2; } } else p = q + count; } #ifdef CONFIG_SMP flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(local_flush_cache_all); #else flush_cacheall = (void (*)(void))BTFIXUPVAL_CALL(flush_cache_all); #endif if (!flush_cacheall) { prom_printf(fca_und); prom_halt(); } (*flush_cacheall)(); }