Commit 60de2d2d authored by Pekka Pessi's avatar Pekka Pessi Committed by Jassi Brar
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mailbox: tegra-hsp: Flush whole channel 



The txdone can re-fill the mailbox. Keep polling the mailbox during the
flush until all the messages have been delivered.

This fixes an issue with the Tegra Combined UART (TCU) where output can
get truncated under high traffic load.

Signed-off-by: default avatarPekka Pessi <ppessi@nvidia.com>
Tested-by: default avatarJon Hunter <jonathanh@nvidia.com>
Fixes: 91b1b1c3 ("mailbox: tegra-hsp: Add support for shared mailboxes")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
Reviewed-by: default avatarJon Hunter <jonathanh@nvidia.com>
Signed-off-by: default avatarJassi Brar <jaswinder.singh@linaro.org>
parent ffb217a1

drivers/mailbox/tegra-hsp.c

+5 −0
Original line number Diff line number Diff line
@@ -412,6 +412,11 @@ static int tegra_hsp_mailbox_flush(struct mbox_chan *chan, 
		value = tegra_hsp_channel_readl(ch, HSP_SM_SHRD_MBOX);

		if ((value & HSP_SM_SHRD_MBOX_FULL) == 0) {

			mbox_chan_txdone(chan, 0);



			/* Wait until channel is empty */

			if (chan->active_req != NULL)

				continue;



			return 0;

		}