topic Re: How to flash a kinetis using SWD protocol in Kinetis Microcontrollers

How to flash a kinetis using SWD protocol

topir — Tue, 03 Nov 2015 14:41:11 GMT

Hi,

I am trying to program the flash of MKL05 using SWD (with GPIO).

1. The KL05 Sub-Family Reference Manual, Rev 3.1, November 2012 states at page 139, that AHB-AP is connected to SW-DP. But, from the ARM infocenter I could not find AHB-AP documentation related to Cortex-M0 (Only M1, M3 and M4). Which version of AHB-AP documentation should I refer to?

2. I have succesfully accessed MDM-AP, can read IDR (0x04770031) & Status, and can write/read Control registers. I can also read IDR of AHB-AP. But after writing 0x00000000 to AHB-AP.TAR, the SW-DP.CTRL/STAT shows STICKYERR set (first read of CTRL/STAT after TAR write is 0x00000040, second read of CTRL/STAT after TAR write is 0x00000060). Any AP access after this returns ACK = 4 (fail).

2.5. The AHB-AP.CSW == 0x03000042. Based on Cortex-M1 documentation, bits 27:24 are HPROT[3:0].

Any ideas what is causing this and how to proceed to access Flash Memory Module (FTFA)? Could it be a missing (power) enable somewhere?

BR, -Topi

Re: How to flash a kinetis using SWD protocol

topir — Tue, 03 Nov 2015 15:18:58 GMT

2. Sorry, the AHB-AP IDR is 0x04770031. MDM-AP IDR is 0x001C0020.

BR, -Topi

Re: How to flash a kinetis using SWD protocol

topir — Wed, 04 Nov 2015 09:08:02 GMT

Found the problem:

The picture on page 139 of KL05 Sub-Family Reference Manual, Rev. 3.1, November 2012

http://cache.freescale.com/files/32bit/doc/ref_manual/KL05P48M48SF1RM.pdf?fpsp=1&WT_TYPE=Reference%20Manuals&WT_VENDOR=F…

States that the address range of MDM-AP is 0x00 .. 0x3F.

ARM documentation (MEM-AP) states the address range being 0x00 .. 0xFC (2 LSBs being zero).

I tried to access AHB-AP with address 0x04 (TAR register), but actually it wrote to address 0x10 (BD0), which caused bus error, I guess.

FREESCALE: You should correct the Keystone documentation to express the MDM-AP addresses in the same address format as ARM is doing. Agree?

BR, -Topi

Re: How to flash a kinetis using SWD protocol

Jorge_Gonzalez — Fri, 06 Nov 2015 18:04:51 GMT

Hello Topi Rinkinen:

Glad to see you found the issue. The addresses in the Reference Manual [0x00/0x01/0x3F] actually refer to the bits SELECT[7:2] as implied by the comments:

So with the 2-bits shift the actual addresses are as you found [0x00/0x04/0xFC]. I agree this can be confusing.

Let me pass your feedback, although the whole range of Kinetis manuals use the same scheme, so this would need a massive update effort.

Regards!

Jorge Gonzalez

Re: How to flash a kinetis using SWD protocol

topir — Mon, 09 Nov 2015 09:00:12 GMT

Hi,

One more obstacle found..

Flash module (FTFA) registers FTFA_FCCOB[0..B] need to be written during flashing. I struggled a while with a problem that the registers did not read back the written value, but always returned zero.

The solution is to disable COP watchdog in SIM module, right after the reset is released. Then the flashing procedures work as documented.

This information is missing from AN4835. Suggest to update that too.

BR, -Topi