From 867818dd132e6cda322c5941d04a4971ec4a753a Mon Sep 17 00:00:00 2001 From: Bumyong Lee Date: Tue, 19 Dec 2023 14:50:26 +0900 Subject: [PATCH] dmaengine: pl330: issue_pending waits until WFP state [ Upstream commit 22a9d9585812440211b0b34a6bc02ade62314be4 ] According to DMA-330 errata notice[1] 71930, DMAKILL cannot clear internal signal, named pipeline_req_active. it makes that pl330 would wait forever in WFP state although dma already send dma request if pl330 gets dma request before entering WFP state. The errata suggests that polling until entering WFP state as workaround and then peripherals allows to issue dma request. [1]: https://developer.arm.com/documentation/genc008428/latest Signed-off-by: Bumyong Lee Link: https://lore.kernel.org/r/20231219055026.118695-1-bumyong.lee@samsung.com Signed-off-by: Vinod Koul Stable-dep-of: afc89870ea67 ("dmaengine: Revert "dmaengine: pl330: issue_pending waits until WFP state"") Signed-off-by: Sasha Levin --- drivers/dma/pl330.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 3cf0b38387ae..c29744bfdf2c 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -1053,6 +1053,9 @@ static bool _trigger(struct pl330_thread *thrd) thrd->req_running = idx; + if (desc->rqtype == DMA_MEM_TO_DEV || desc->rqtype == DMA_DEV_TO_MEM) + UNTIL(thrd, PL330_STATE_WFP); + return true; }