Problem
dap->ap_current is register value, not field value.
it restores invalid ap when it calls dap_ap_select(dap, ap_old) later.
* assume the current ap is 1, dap->ap_current value would be (1 << 24).
ap_old = dap->ap_current; <-- ap_old = 1<<24 = 0x1000000.
...
dap_ap_select(dap, ap_old); <-- select 0x1000000, not 1.
* All AP registers accessing fail afterwards.
One of the reproducible case(s): CORE residents in AP >= 1
dap_lookup_cs_component() being used to find PE(*).
In most cases, PE would be found in AP==0, hence the problem is hidden.
When AP number is 1, dap->ap_current would have the value of 1<<24.
Anyone get the AP value with dap->ap_current and resotre it later would
select the wrong AP and all accessing later would fail.
The ARM Versatile and/or FPGA would have better chance to provide this
kind of environment that PE residents in AP>=1. As they have an 'umbrella'
system at AP0, and main system at AP>=1.
* PE: Processing Element. AKA Core. See ARM Glossary at
http://infocenter.arm.com/help/topic/com.arm.doc.aeg0014g/ABCDEFGH.html
Fix
Use dap_ap_get_select() to get ap value.
a. Retrieve current ap value by calling dap_ap_get_select();
src/flash/nor/kinetis.c
src/target/arm_adi_v5.c
b. The code is correct (dap->ap_current >> 24), but it's better to use
dap_ap_get_select() so everything could be synchronized.
src/flash/nor/sim3x.c
Change-Id: I97b5a13a3fc5506cf287e299c6c35699374de74f
Signed-off-by: Alamy Liu <alamy.liu@gmail.com>
Reviewed-on: http://openocd.zylin.com/2935
Reviewed-by: Andreas Färber <afaerber@suse.de>
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>
}
int retval;
- const uint8_t original_ap = dap->ap_current;
+ const uint8_t original_ap = dap_ap_get_select(dap);
/*
* ... Power on the processor, or if power has already been
uint32_t val;
int retval;
- const uint8_t origninal_ap = dap->ap_current;
+ const uint8_t origninal_ap = dap_ap_get_select(dap);
dap_ap_select(dap, 1);
return ERROR_FAIL;
}
- const uint8_t origninal_ap = dap->ap_current >> 24;
+ const uint8_t origninal_ap = dap_ap_get_select(dap);
dap_ap_select(dap, SIM3X_AP);
ret = ap_read_register(dap, SIM3X_AP_ID, &val);
return ERROR_FAIL;
}
} else {
- const uint8_t origninal_ap = dap->ap_current >> 24;
+ const uint8_t origninal_ap = dap_ap_get_select(dap);
dap_ap_select(dap, SIM3X_AP);
/* check SIM3X_AP_ID */
if (ap >= 256)
return ERROR_COMMAND_SYNTAX_ERROR;
- ap_old = dap->ap_current;
+ ap_old = dap_ap_get_select(dap);
dap_ap_select(dap, ap);
retval = dap_queue_ap_read(dap, AP_REG_BASE, dbgbase);
return ERROR_COMMAND_SYNTAX_ERROR;
*addr = 0;
- ap_old = dap->ap_current;
+ ap_old = dap_ap_get_select(dap);
dap_ap_select(dap, ap);
do {
if (retval != ERROR_OK)
return retval;
- ap_old = dap->ap_current;
+ ap_old = dap_ap_get_select(dap);
dap_ap_select(dap, ap);
/* Now we read ROM table ID registers, ref. ARM IHI 0029B sec */