[PATCH 1/2] slimbus: qcom-ngd-ctrl: check for device runtime PM status during ISR

[PATCH 1/2] slimbus: qcom-ngd-ctrl: check for device runtime PM status during ISR

[Krzysztof Kozlowski]

Slimbus core interrupt is getting fired after suspend. At this point
ADSP slimbus hardware is off with gated clocks which is leading to an
unclocked access when HLOS slimbus tried to read the interrupt
status register in the ISR.

Co-developed-by: Chandana Kishori Chiluveru <cchiluve@codeaurora.org>
Signed-off-by: Chandana Kishori Chiluveru <cchiluve@codeaurora.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 drivers/slimbus/qcom-ngd-ctrl.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
index cec11aa106bf..ba36eb5c0de3 100644
--- a/drivers/slimbus/qcom-ngd-ctrl.c
+++ b/drivers/slimbus/qcom-ngd-ctrl.c
@@ -763,7 +763,14 @@ static irqreturn_t qcom_slim_ngd_interrupt(int irq, void *d)
 {
 	struct qcom_slim_ngd_ctrl *ctrl = d;
 	void __iomem *base = ctrl->ngd->base;
-	u32 stat = readl(base + NGD_INT_STAT);
+	u32 stat;
+
+	if (pm_runtime_suspended(ctrl->ctrl.dev)) {
+		dev_warn_once(ctrl->dev, "Interrupt received while suspended\n");
+		return IRQ_NONE;
+	}
+
+	stat = readl(base + NGD_INT_STAT);
 
 	if ((stat & NGD_INT_MSG_BUF_CONTE) ||
 		(stat & NGD_INT_MSG_TX_INVAL) || (stat & NGD_INT_DEV_ERR) ||
-- 
2.34.1

[PATCH 2/2] slimbus: qcom-ngd-ctrl: drop PM runtime counter on transfer error paths

[Krzysztof Kozlowski]

If transfer in qcom_slim_ngd_xfer_msg_sync() fails, we need to drop the
PM runtime usage counter to have it balanced.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 drivers/slimbus/qcom-ngd-ctrl.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
index ba36eb5c0de3..ac84fdc2822f 100644
--- a/drivers/slimbus/qcom-ngd-ctrl.c
+++ b/drivers/slimbus/qcom-ngd-ctrl.c
@@ -919,21 +919,29 @@ static int qcom_slim_ngd_xfer_msg_sync(struct slim_controller *ctrl,
 	DECLARE_COMPLETION_ONSTACK(done);
 	int ret, timeout;
 
-	pm_runtime_get_sync(ctrl->dev);
+	ret = pm_runtime_get_sync(ctrl->dev);
+	if (ret < 0)
+		goto pm_put;
 
 	txn->comp = &done;
 
 	ret = qcom_slim_ngd_xfer_msg(ctrl, txn);
 	if (ret)
-		return ret;
+		goto pm_put;
 
 	timeout = wait_for_completion_timeout(&done, HZ);
 	if (!timeout) {
 		dev_err(ctrl->dev, "TX timed out:MC:0x%x,mt:0x%x", txn->mc,
 				txn->mt);
-		return -ETIMEDOUT;
+		ret = -ETIMEDOUT;
+		goto pm_put;
 	}
 	return 0;
+
+pm_put:
+	pm_runtime_put(ctrl->dev);
+
+	return ret;
 }
 
 static int qcom_slim_ngd_enable_stream(struct slim_stream_runtime *rt)
-- 
2.34.1

Re: [PATCH 1/2] slimbus: qcom-ngd-ctrl: check for device runtime PM status during ISR

[Srinivas Kandagatla]

On 28/09/2022 14:20, Krzysztof Kozlowski wrote:
> Slimbus core interrupt is getting fired after suspend. At this point
> ADSP slimbus hardware is off with gated clocks which is leading to an
> unclocked access when HLOS slimbus tried to read the interrupt
> status register in the ISR.
> 
> Co-developed-by: Chandana Kishori Chiluveru <cchiluve@codeaurora.org>
> Signed-off-by: Chandana Kishori Chiluveru <cchiluve@codeaurora.org>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---

Applied both,

--srini
>   drivers/slimbus/qcom-ngd-ctrl.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
> index cec11aa106bf..ba36eb5c0de3 100644
> --- a/drivers/slimbus/qcom-ngd-ctrl.c
> +++ b/drivers/slimbus/qcom-ngd-ctrl.c
> @@ -763,7 +763,14 @@ static irqreturn_t qcom_slim_ngd_interrupt(int irq, void *d)
>   {
>   	struct qcom_slim_ngd_ctrl *ctrl = d;
>   	void __iomem *base = ctrl->ngd->base;
> -	u32 stat = readl(base + NGD_INT_STAT);
> +	u32 stat;
> +
> +	if (pm_runtime_suspended(ctrl->ctrl.dev)) {
> +		dev_warn_once(ctrl->dev, "Interrupt received while suspended\n");
> +		return IRQ_NONE;
> +	}
> +
> +	stat = readl(base + NGD_INT_STAT);
>   
>   	if ((stat & NGD_INT_MSG_BUF_CONTE) ||
>   		(stat & NGD_INT_MSG_TX_INVAL) || (stat & NGD_INT_DEV_ERR) ||