remoteproc: qcom: q6v5: Use qmp_send to update co-processor load state

The power domains exposed by the AOSS QMP driver control the load state
resources linked to modem, adsp, cdsp remoteprocs. These are used to
notify the Always on Subsystem (AOSS) that a particular co-processor is
up/down. AOSS uses this information to wait for the co-processors to
suspend before starting its sleep sequence.

These co-processors enter low-power modes independent to that of the
application processor and the load state resources linked to them are
expected to remain unaltered across system suspend/resume cycles. To
achieve this behavior lets stop using the power-domains exposed by the
AOSS QMP node and replace them with generic qmp_send interface instead.

Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
[bjorn: Fixed up build error in q6v5_wcss_remove()]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1631800770-371-5-git-send-email-sibis@codeaurora.org

1 files changed, 56 insertions, 1 deletions

diff --git a/drivers/remoteproc/qcom_q6v5.c b/drivers/remoteproc/qcom_q6v5.c
index 7e9244c748da..eada7e34f3af 100644
--- a/drivers/remoteproc/qcom_q6v5.c
+++ b/drivers/remoteproc/qcom_q6v5.c
@@ -16,8 +16,30 @@
 #include "qcom_common.h"
 #include "qcom_q6v5.h"
 
+#define Q6V5_LOAD_STATE_MSG_LEN	64
 #define Q6V5_PANIC_DELAY_MS	200
 
+static int q6v5_load_state_toggle(struct qcom_q6v5 *q6v5, bool enable)
+{
+	char buf[Q6V5_LOAD_STATE_MSG_LEN];
+	int ret;
+
+	if (!q6v5->qmp)
+		return 0;
+
+	ret = snprintf(buf, sizeof(buf),
+		       "{class: image, res: load_state, name: %s, val: %s}",
+		       q6v5->load_state, enable ? "on" : "off");
+
+	WARN_ON(ret >= Q6V5_LOAD_STATE_MSG_LEN);
+
+	ret = qmp_send(q6v5->qmp, buf, sizeof(buf));
+	if (ret)
+		dev_err(q6v5->dev, "failed to toggle load state\n");
+
+	return ret;
+}
+
 /**
  * qcom_q6v5_prepare() - reinitialize the qcom_q6v5 context before start
  * @q6v5:	reference to qcom_q6v5 context to be reinitialized
@@ -26,6 +48,12 @@
  */
 int qcom_q6v5_prepare(struct qcom_q6v5 *q6v5)
 {
+	int ret;
+
+	ret = q6v5_load_state_toggle(q6v5, true);
+	if (ret)
+		return ret;
+
 	reinit_completion(&q6v5->start_done);
 	reinit_completion(&q6v5->stop_done);
 
@@ -47,6 +75,7 @@ EXPORT_SYMBOL_GPL(qcom_q6v5_prepare);
 int qcom_q6v5_unprepare(struct qcom_q6v5 *q6v5)
 {
 	disable_irq(q6v5->handover_irq);
+	q6v5_load_state_toggle(q6v5, false);
 
 	return !q6v5->handover_issued;
 }
@@ -196,12 +225,13 @@ EXPORT_SYMBOL_GPL(qcom_q6v5_panic);
  * @pdev:	platform_device reference for acquiring resources
  * @rproc:	associated remoteproc instance
  * @crash_reason: SMEM id for crash reason string, or 0 if none
+ * @load_state: load state resource string
  * @handover:	function to be called when proxy resources should be released
  *
  * Return: 0 on success, negative errno on failure
  */
 int qcom_q6v5_init(struct qcom_q6v5 *q6v5, struct platform_device *pdev,
-		   struct rproc *rproc, int crash_reason,
+		   struct rproc *rproc, int crash_reason, const char *load_state,
 		   void (*handover)(struct qcom_q6v5 *q6v5))
 {
 	int ret;
@@ -286,9 +316,34 @@ int qcom_q6v5_init(struct qcom_q6v5 *q6v5, struct platform_device *pdev,
 		return PTR_ERR(q6v5->state);
 	}
 
+	q6v5->load_state = devm_kstrdup_const(&pdev->dev, load_state, GFP_KERNEL);
+	q6v5->qmp = qmp_get(&pdev->dev);
+	if (IS_ERR(q6v5->qmp)) {
+		if (PTR_ERR(q6v5->qmp) != -ENODEV)
+			return dev_err_probe(&pdev->dev, PTR_ERR(q6v5->qmp),
+					     "failed to acquire load state\n");
+		q6v5->qmp = NULL;
+	} else if (!q6v5->load_state) {
+		if (!load_state)
+			dev_err(&pdev->dev, "load state resource string empty\n");
+
+		qmp_put(q6v5->qmp);
+		return load_state ? -ENOMEM : -EINVAL;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(qcom_q6v5_init);
 
+/**
+ * qcom_q6v5_deinit() - deinitialize the q6v5 common struct
+ * @q6v5:	reference to qcom_q6v5 context to be deinitialized
+ */
+void qcom_q6v5_deinit(struct qcom_q6v5 *q6v5)
+{
+	qmp_put(q6v5->qmp);
+}
+EXPORT_SYMBOL_GPL(qcom_q6v5_deinit);
+
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("Qualcomm Peripheral Image Loader for Q6V5");