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> |
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| bayou | ||
| coreinfo | ||
| external | ||
| libpayload | ||
| nvramcui | ||
| tianocoreboot | ||
| ubootcli | ||