diff options
Diffstat (limited to 'src/arch/x86/lib/thread.c')
-rw-r--r-- | src/arch/x86/lib/thread.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/src/arch/x86/lib/thread.c b/src/arch/x86/lib/thread.c new file mode 100644 index 0000000..06f8a15 --- /dev/null +++ b/src/arch/x86/lib/thread.c @@ -0,0 +1,58 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2013 Google, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <thread.h> + +/* The stack frame looks like the following after a pushad instruction. */ +struct pushad_regs { + uint32_t edi; /* Offset 0x00 */ + uint32_t esi; /* Offset 0x04 */ + uint32_t ebp; /* Offset 0x08 */ + uint32_t esp; /* Offset 0x0c */ + uint32_t ebx; /* Offset 0x10 */ + uint32_t edx; /* Offset 0x14 */ + uint32_t ecx; /* Offset 0x18 */ + uint32_t eax; /* Offset 0x1c */ +}; + +static inline uintptr_t push_stack(uintptr_t cur_stack, uintptr_t value) +{ + uintptr_t *addr; + + cur_stack -= sizeof(value); + addr = (uintptr_t *)cur_stack; + *addr = value; + return cur_stack; +} + +void arch_prepare_thread(struct thread *t, + void asmlinkage (*thread_entry)(void *), void *arg) +{ + uintptr_t stack = t->stack_current; + + /* Imitate thread_entry(t) with return address of 0. thread_entry() + * is assumed to never return. */ + stack = push_stack(stack, (uintptr_t)arg); + stack = push_stack(stack, (uintptr_t)0); + stack = push_stack(stack, (uintptr_t)thread_entry); + /* Make room for the registers. Ignore intial values. */ + stack -= sizeof(struct pushad_regs); + + t->stack_current = stack; +} |