This is an automated email from Gerrit.
"Bohdan Tymkiv <bohdan...@gmail.com>" just uploaded a new patch set to Gerrit,
which you can find at https://review.openocd.org/c/openocd/+/6762
-- gerrit
commit 1dc9016743526a1b2cf8da6f4f1d143a570e8d4a
Author: Bohdan Tymkiv <bohdan...@gmail.com>
Date: Thu Dec 2 10:08:33 2021 +0200
target/arm_jtag.h: fix wrong comparison in arm_jtag_set_instr
Change [1] introduced a performance regression that results in
comparison in arm_jtag_set_instr() to be always true if the
length of the IR register is not 8 bit. The value on the left
side of the != operator contains only tap->ir_length number of
bits while value on the right is full 8-bit instruction code.
This forces OpenOCD to update the JTAG IR register on each
transaction even if the instruction in the JTAG IR register
is correct. This causes noticeable performance degradation,
especially with slow JTAG adapters.
[1] https://review.openocd.org/c/openocd/+/6285
time ./src/openocd -s tcl/ -f interface/cmsis-dap.cfg \
-c "transport select jtag" -f target/psoc6.cfg \
-c "init; load_image data.bin 0x08000000; exit"
Without this change:
real 0m4,863s
user 0m0,074s
sys 0m0,128s
With this change:
real 0m3,083s
user 0m0,038s
sys 0m0,098s
Signed-off-by: Bohdan Tymkiv <bohdan...@gmail.com>
Change-Id: Iaded83a04ecc7e65f18256afae582267ccc1fc59
diff --git a/src/target/arm_jtag.h b/src/target/arm_jtag.h
index bf5b83748..013c53a4e 100644
--- a/src/target/arm_jtag.h
+++ b/src/target/arm_jtag.h
@@ -42,7 +42,7 @@ static inline int arm_jtag_set_instr(struct jtag_tap *tap,
uint32_t new_instr, void *no_verify_capture, tap_state_t
end_state)
{
/* inline most common code path */
- if (buf_get_u32(tap->cur_instr, 0, tap->ir_length) != new_instr)
+ if (buf_get_u32(tap->cur_instr, 0, tap->ir_length) !=
buf_get_u32((uint8_t *)&new_instr, 0, tap->ir_length))
return arm_jtag_set_instr_inner(tap, new_instr,
no_verify_capture, end_state);
return ERROR_OK;
--
