coreboot/payloads
Yogesh Lal 61528884ad libpayload: ipq808x: stale interrupt shall not be cleared unconditionally
The serial driver hangs in cases when FIFO has more than single word to be
processed. Easiest way to reproduce is to paste a string of greater than 4
characters in cli.

Clearing the RXSTALE interrupt without draining all the characters from FIFO
leads to the issue as the driver is dependent on msm_boot_uart_dm_read
function to reinitialize for next transfer.

Logically the driver is organized in such a manner that next transfer never
gets initiated till rx_data_read < total_rx_data. Clearing the RXSTALE without
consideration of total number of characters (or words) unprocessed makes the
msm_boot_uart_dm_read to return on the first if conditional. Thus the driver is
stuck forever.

A quick fix is to avoid clearing the stale interrupt. Reset is handled whenever
a new transfer is initialized in msm_boot_uart_dm_init_rx_transfer.

BUG=chrome-os-partner:29542
TEST=manual
	-Paste a string greater than 4 characters in cli.

Change-Id: I016afb01a77cd14764f0176f6bf144fb29796c2f
Signed-off-by: Yogesh Lal <ylal@codeaurora.org>
Reviewed-on: https://chromium-review.googlesource.com/209512
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Commit-Queue: Vadim Bendebury <vbendeb@chromium.org>
Tested-by: Vadim Bendebury <vbendeb@chromium.org>
2014-07-26 02:43:49 +00:00
..
bayou GPLv2 notice: Unify all files to just use one space in »MA 02110-1301« 2013-03-01 10:16:08 +01:00
coreinfo GPLv2 notice: Unify all files to just use one space in »MA 02110-1301« 2013-03-01 10:16:08 +01:00
external bump SeaBIOS to 1.7.2.1 2013-03-04 11:00:17 +01:00
libpayload libpayload: ipq808x: stale interrupt shall not be cleared unconditionally 2014-07-26 02:43:49 +00:00
nvramcui GPLv2 notice: Unify all files to just use one space in »MA 02110-1301« 2013-03-01 10:16:08 +01:00
tianocoreboot ARM: Generalize armv7 as arm. 2013-10-02 09:18:44 +00:00
ubootcli payload/ubootcli: Minimal changes to fix build errors. 2014-05-15 05:23:22 +00:00