static void __init create_trampoline(unsigned long addr)
{
unsigned int *p = (unsigned int *)addr;
/* The maximum range of a single instruction branch, is the current
* instruction's address + (32 MB - 4) bytes. For the trampoline we
* need to branch to current address + 32 MB. So we insert a nop at
* the trampoline address, then the next instruction (+ 4 bytes)
* does a branch to (32 MB - 4). The net effect is that when we
* branch to "addr" we jump to ("addr" + 32 MB). Although it requires
* two instructions it doesn't require any registers.
*/
patch_instruction(p, PPC_INST_NOP);
patch_branch(++p, addr + PHYSICAL_START, 0);
}
static void __init create_trampoline(unsigned long addr)
{
unsigned int *p = (unsigned int *)addr;
/*
*/
patch_instruction(p, PPC_INST_NOP);
patch_branch(++p, addr + PHYSICAL_START, 0);
}
static int __init
smp_86xx_kick_cpu(int nr)
{
unsigned int save_vector;
unsigned long target, flags;
int n = 0;
unsigned int *vector = (unsigned int *)(KERNELBASE + 0x100);
if (nr < 0 || nr >= NR_CPUS)
return -ENOENT;
pr_debug("smp_86xx_kick_cpu: kick CPU #%d\n", nr);
local_irq_save(flags);
save_vector = *vector;
target = (unsigned long) __secondary_start_mpc86xx;
patch_branch(vector, target, BRANCH_SET_LINK);
smp_86xx_release_core(nr);
while ((__secondary_hold_acknowledge != nr) && (n++, n < 1000))
mdelay(1);
*vector = save_vector;
flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
local_irq_restore(flags);
pr_debug("wait CPU #%d for %d msecs.\n", nr, n);
return 0;
}
/* Returns whether it had to change page protections */
static bool
patch_coarse_branch(cache_pc stub, cache_pc tgt, bool hot_patch,
coarse_info_t *info /*OPTIONAL*/)
{
// COMPLETEDD #498 patch_coarse_branch
bool stubs_readonly = false;
bool stubs_restore = false;
if (DYNAMO_OPTION(persist_protect_stubs)) {
if (info == NULL)
info = get_stub_coarse_info(stub);
ASSERT(info != NULL);
if (info->stubs_readonly) {
stubs_readonly = true;
stubs_restore = true;
/* if we don't preserve mapped-in COW state the protection change
* will fail (case 10570)
*/
make_copy_on_writable((byte *)PAGE_START(entrance_stub_jmp(stub)),
/* stub jmp can't cross page boundary (can't
* cross cache line in fact) */
PAGE_SIZE);
if (DYNAMO_OPTION(persist_protect_stubs_limit) > 0) {
info->stubs_write_count++;
if (info->stubs_write_count >
DYNAMO_OPTION(persist_protect_stubs_limit)) {
SYSLOG_INTERNAL_WARNING_ONCE("pcache stubs over write limit");
STATS_INC(pcache_unprot_over_limit);
stubs_restore = false;
info->stubs_readonly = false;
}
}
}
}
patch_branch(entrance_stub_jmp(stub), tgt, HOT_PATCHABLE);
if (stubs_restore)
make_unwritable((byte *)PAGE_START(entrance_stub_jmp(stub)), PAGE_SIZE);
return stubs_readonly;
}
