Commit 3f93a4f2 authored Jun 21, 2019 by Robin Gong Committed by Vinod Koul Jul 05, 2019

dmaengine: imx-sdma: remove BD_INTR for channel0



It is possible for an irq triggered by channel0 to be received later
after clks are disabled once firmware loaded during sdma probe. If
that happens then clearing them by writing to SDMA_H_INTR won't work
and the kernel will hang processing infinite interrupts. Actually,
don't need interrupt triggered on channel0 since it's pollling
SDMA_H_STATSTOP to know channel0 done rather than interrupt in
current code, just clear BD_INTR to disable channel0 interrupt to
avoid the above case.
This issue was brought by commit 1d069bfa ("dmaengine: imx-sdma:
ack channel 0 IRQ in the interrupt handler") which didn't take care
the above case.

Fixes: 1d069bfa ("dmaengine: imx-sdma: ack channel 0 IRQ in the interrupt handler")
Cc: stable@vger.kernel.org #5.0+
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reported-by: Sven Van Asbroeck <thesven73@gmail.com>
Tested-by: Sven Van Asbroeck <thesven73@gmail.com>
Reviewed-by: Michael Olbrich <m.olbrich@pengutronix.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

parent 2b8066c3

drivers/dma/imx-sdma.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -703,7 +703,7 @@ static int sdma_load_script(struct sdma_engine sdma, void buf, int size,
		spin_lock_irqsave(&sdma->channel_0_lock, flags);

		bd0->mode.command = C0_SETPM;
		bd0->mode.status = BD_DONE \| BD_INTR \| BD_WRAP \| BD_EXTD;
		bd0->mode.status = BD_DONE \| BD_WRAP \| BD_EXTD;
		bd0->mode.count = size / 2;
		bd0->buffer_addr = buf_phys;
		bd0->ext_buffer_addr = address;
		@@ -1025,7 +1025,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
		context->gReg[7] = sdmac->watermark_level;

		bd0->mode.command = C0_SETDM;
		bd0->mode.status = BD_DONE \| BD_INTR \| BD_WRAP \| BD_EXTD;
		bd0->mode.status = BD_DONE \| BD_WRAP \| BD_EXTD;
		bd0->mode.count = sizeof(*context) / 4;
		bd0->buffer_addr = sdma->context_phys;
		bd0->ext_buffer_addr = 2048 + (sizeof(context) / 4) channel;

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