diff options
Diffstat (limited to 'arch/ia64/kernel/patch.c')
| -rw-r--r-- | arch/ia64/kernel/patch.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/arch/ia64/kernel/patch.c b/arch/ia64/kernel/patch.c new file mode 100644 index 000000000..7f21a8c57 --- /dev/null +++ b/arch/ia64/kernel/patch.c @@ -0,0 +1,237 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Instruction-patching support. + * + * Copyright (C) 2003 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + */ +#include <linux/init.h> +#include <linux/string.h> + +#include <asm/patch.h> +#include <asm/processor.h> +#include <asm/sections.h> +#include <asm/unistd.h> + +/* + * This was adapted from code written by Tony Luck: + * + * The 64-bit value in a "movl reg=value" is scattered between the two words of the bundle + * like this: + * + * 6 6 5 4 3 2 1 + * 3210987654321098765432109876543210987654321098765432109876543210 + * ABBBBBBBBBBBBBBBBBBBBBBBCCCCCCCCCCCCCCCCCCDEEEEEFFFFFFFFFGGGGGGG + * + * CCCCCCCCCCCCCCCCCCxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx + * xxxxAFFFFFFFFFEEEEEDxGGGGGGGxxxxxxxxxxxxxBBBBBBBBBBBBBBBBBBBBBBB + */ +static u64 +get_imm64 (u64 insn_addr) +{ + u64 *p = (u64 *) (insn_addr & -16); /* mask out slot number */ + + return ( (p[1] & 0x0800000000000000UL) << 4) | /*A*/ + ((p[1] & 0x00000000007fffffUL) << 40) | /*B*/ + ((p[0] & 0xffffc00000000000UL) >> 24) | /*C*/ + ((p[1] & 0x0000100000000000UL) >> 23) | /*D*/ + ((p[1] & 0x0003e00000000000UL) >> 29) | /*E*/ + ((p[1] & 0x07fc000000000000UL) >> 43) | /*F*/ + ((p[1] & 0x000007f000000000UL) >> 36); /*G*/ +} + +/* Patch instruction with "val" where "mask" has 1 bits. */ +void +ia64_patch (u64 insn_addr, u64 mask, u64 val) +{ + u64 m0, m1, v0, v1, b0, b1, *b = (u64 *) (insn_addr & -16); +# define insn_mask ((1UL << 41) - 1) + unsigned long shift; + + b0 = b[0]; b1 = b[1]; + shift = 5 + 41 * (insn_addr % 16); /* 5 bits of template, then 3 x 41-bit instructions */ + if (shift >= 64) { + m1 = mask << (shift - 64); + v1 = val << (shift - 64); + } else { + m0 = mask << shift; m1 = mask >> (64 - shift); + v0 = val << shift; v1 = val >> (64 - shift); + b[0] = (b0 & ~m0) | (v0 & m0); + } + b[1] = (b1 & ~m1) | (v1 & m1); +} + +void +ia64_patch_imm64 (u64 insn_addr, u64 val) +{ + /* The assembler may generate offset pointing to either slot 1 + or slot 2 for a long (2-slot) instruction, occupying slots 1 + and 2. */ + insn_addr &= -16UL; + ia64_patch(insn_addr + 2, + 0x01fffefe000UL, ( ((val & 0x8000000000000000UL) >> 27) /* bit 63 -> 36 */ + | ((val & 0x0000000000200000UL) << 0) /* bit 21 -> 21 */ + | ((val & 0x00000000001f0000UL) << 6) /* bit 16 -> 22 */ + | ((val & 0x000000000000ff80UL) << 20) /* bit 7 -> 27 */ + | ((val & 0x000000000000007fUL) << 13) /* bit 0 -> 13 */)); + ia64_patch(insn_addr + 1, 0x1ffffffffffUL, val >> 22); +} + +void +ia64_patch_imm60 (u64 insn_addr, u64 val) +{ + /* The assembler may generate offset pointing to either slot 1 + or slot 2 for a long (2-slot) instruction, occupying slots 1 + and 2. */ + insn_addr &= -16UL; + ia64_patch(insn_addr + 2, + 0x011ffffe000UL, ( ((val & 0x0800000000000000UL) >> 23) /* bit 59 -> 36 */ + | ((val & 0x00000000000fffffUL) << 13) /* bit 0 -> 13 */)); + ia64_patch(insn_addr + 1, 0x1fffffffffcUL, val >> 18); +} + +/* + * We need sometimes to load the physical address of a kernel + * object. Often we can convert the virtual address to physical + * at execution time, but sometimes (either for performance reasons + * or during error recovery) we cannot to this. Patch the marked + * bundles to load the physical address. + */ +void __init +ia64_patch_vtop (unsigned long start, unsigned long end) +{ + s32 *offp = (s32 *) start; + u64 ip; + + while (offp < (s32 *) end) { + ip = (u64) offp + *offp; + + /* replace virtual address with corresponding physical address: */ + ia64_patch_imm64(ip, ia64_tpa(get_imm64(ip))); + ia64_fc((void *) ip); + ++offp; + } + ia64_sync_i(); + ia64_srlz_i(); +} + +/* + * Disable the RSE workaround by turning the conditional branch + * that we tagged in each place the workaround was used into an + * unconditional branch. + */ +void __init +ia64_patch_rse (unsigned long start, unsigned long end) +{ + s32 *offp = (s32 *) start; + u64 ip, *b; + + while (offp < (s32 *) end) { + ip = (u64) offp + *offp; + + b = (u64 *)(ip & -16); + b[1] &= ~0xf800000L; + ia64_fc((void *) ip); + ++offp; + } + ia64_sync_i(); + ia64_srlz_i(); +} + +void __init +ia64_patch_mckinley_e9 (unsigned long start, unsigned long end) +{ + static int first_time = 1; + int need_workaround; + s32 *offp = (s32 *) start; + u64 *wp; + + need_workaround = (local_cpu_data->family == 0x1f && local_cpu_data->model == 0); + + if (first_time) { + first_time = 0; + if (need_workaround) + printk(KERN_INFO "Leaving McKinley Errata 9 workaround enabled\n"); + } + if (need_workaround) + return; + + while (offp < (s32 *) end) { + wp = (u64 *) ia64_imva((char *) offp + *offp); + wp[0] = 0x0000000100000011UL; /* nop.m 0; nop.i 0; br.ret.sptk.many b6 */ + wp[1] = 0x0084006880000200UL; + wp[2] = 0x0000000100000000UL; /* nop.m 0; nop.i 0; nop.i 0 */ + wp[3] = 0x0004000000000200UL; + ia64_fc(wp); ia64_fc(wp + 2); + ++offp; + } + ia64_sync_i(); + ia64_srlz_i(); +} + +static void __init +patch_fsyscall_table (unsigned long start, unsigned long end) +{ + extern unsigned long fsyscall_table[NR_syscalls]; + s32 *offp = (s32 *) start; + u64 ip; + + while (offp < (s32 *) end) { + ip = (u64) ia64_imva((char *) offp + *offp); + ia64_patch_imm64(ip, (u64) fsyscall_table); + ia64_fc((void *) ip); + ++offp; + } + ia64_sync_i(); + ia64_srlz_i(); +} + +static void __init +patch_brl_fsys_bubble_down (unsigned long start, unsigned long end) +{ + extern char fsys_bubble_down[]; + s32 *offp = (s32 *) start; + u64 ip; + + while (offp < (s32 *) end) { + ip = (u64) offp + *offp; + ia64_patch_imm60((u64) ia64_imva((void *) ip), + (u64) (fsys_bubble_down - (ip & -16)) / 16); + ia64_fc((void *) ip); + ++offp; + } + ia64_sync_i(); + ia64_srlz_i(); +} + +void __init +ia64_patch_gate (void) +{ +# define START(name) ((unsigned long) __start_gate_##name##_patchlist) +# define END(name) ((unsigned long)__end_gate_##name##_patchlist) + + patch_fsyscall_table(START(fsyscall), END(fsyscall)); + patch_brl_fsys_bubble_down(START(brl_fsys_bubble_down), END(brl_fsys_bubble_down)); + ia64_patch_vtop(START(vtop), END(vtop)); + ia64_patch_mckinley_e9(START(mckinley_e9), END(mckinley_e9)); +} + +void ia64_patch_phys_stack_reg(unsigned long val) +{ + s32 * offp = (s32 *) __start___phys_stack_reg_patchlist; + s32 * end = (s32 *) __end___phys_stack_reg_patchlist; + u64 ip, mask, imm; + + /* see instruction format A4: adds r1 = imm13, r3 */ + mask = (0x3fUL << 27) | (0x7f << 13); + imm = (((val >> 7) & 0x3f) << 27) | (val & 0x7f) << 13; + + while (offp < end) { + ip = (u64) offp + *offp; + ia64_patch(ip, mask, imm); + ia64_fc((void *)ip); + ++offp; + } + ia64_sync_i(); + ia64_srlz_i(); +} |