michaelh/zephyr
1
0
Fork 0
Code Releases Activity

x86: add support for thread local storage

Browse source 
Adds the necessary bits to initialize TLS in the stack
area and sets up CPU registers during context switch.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This commit is contained in:
Daniel Leung 2020-09-29 15:32:35 -07:00 • committed by Andrew Boie
commit 4b38392ded
9 changed files with 91 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

18
arch/x86/gen_gdt.py
View file

@ -180,6 +180,13 @@ def main():
else:
num_entries = 3
use_tls = False
if ("CONFIG_THREAD_LOCAL_STORAGE" in syms) and ("CONFIG_X86_64" not in syms):
use_tls = True
# x86_64 does not use descriptor for thread local storage
num_entries += 1
gdt_base = syms["_gdt"]
with open(args.output_gdt, "wb") as fp:
@ -205,7 +212,7 @@ def main():
# Selector 0x20: double-fault TSS
fp.write(create_tss_entry(df_tss, 0x67, 0))
if num_entries == 7:
if num_entries >= 7:
# Selector 0x28: code descriptor, dpl = 3
fp.write(create_code_data_entry(0, 0xFFFFF, 3,
FLAGS_GRAN, ACCESS_EX | ACCESS_RW))
@ -214,6 +221,15 @@ def main():
fp.write(create_code_data_entry(0, 0xFFFFF, 3,
FLAGS_GRAN, ACCESS_RW))
if use_tls:
# Selector 0x18, 0x28 or 0x38 (depending on entries above):
# data descriptor, dpl = 3
#
# for use with thread local storage while this will be
# modified at runtime.
fp.write(create_code_data_entry(0, 0xFFFFF, 3,
FLAGS_GRAN, ACCESS_RW))
if __name__ == "__main__":
main()