Commit dbee5229 authored Nov 06, 2019 by Prakash Gupta Committed by Isaac J. Manjarres Dec 02, 2019

iommu: arm-smmu: clear TBU halt request when halt times out



TBU halt request is considered timed out after some wait.
But the halt request is not cleared. This can result in halt request
succeeding subsequently and driver not resuming the TBU. This can cause
functional issue of TBU power collapse or TBU remaining halted.
Clear the TBU halt request in case of timeout.

Change-Id: I2225485cae8146917ea8cfdf3bf50742278ae628
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
[isaacm@codeaurora.org: Use DEBUG_SID_HALT_REQ]
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>

parent 60c00665

drivers/iommu/arm-smmu.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -5010,6 +5010,11 @@ static int qsmmuv500_tbu_halt(struct qsmmuv500_tbu_device *tbu,
		(status & DEBUG_SR_HALT_ACK_VAL),
		0, TBU_DBG_TIMEOUT_US)) {
		dev_err(tbu->dev, "Couldn't halt TBU!\n");

		halt = readl_relaxed(tbu_base + DEBUG_SID_HALT_REG);
		halt &= ~DEBUG_SID_HALT_REQ;
		writel_relaxed(halt, tbu_base + DEBUG_SID_HALT_REG);

		spin_unlock_irqrestore(&tbu->halt_lock, flags);
		return -ETIMEDOUT;
		}