From 6e23e7e3a3ddcf68b6223c3117c9f9103ecf2a0b 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 1d7d4b8d810a..d12939c25a61 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -1051,6 +1051,9 @@ 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; }