[V3 1/7] remoteproc: qcom: pas: Add decrypt shutdown support for modem

[Sibi Sankar <quic_sibis@quicinc.com>]

The initial shutdown request to modem on SM8450 SoCs would start the
decryption process and will keep returning errors until the modem shutdown
is complete. Fix this by retrying shutdowns in fixed intervals.

Err Logs on modem shutdown:
qcom_q6v5_pas 4080000.remoteproc: failed to shutdown: -22
remoteproc remoteproc3: can't stop rproc: -22

Fixes: 5cef9b48458d ("remoteproc: qcom: pas: Add SM8450 remoteproc support")
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
---

v3:
 * Fixup misc. suggestions and rename to adsp_shutdown_poll_decrypt() [Bjorn]

 drivers/remoteproc/qcom_q6v5_pas.c | 43 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c
index 6ae39c5653b1..297700f87fe8 100644
--- a/drivers/remoteproc/qcom_q6v5_pas.c
+++ b/drivers/remoteproc/qcom_q6v5_pas.c
@@ -8,6 +8,7 @@
  */
 
 #include <linux/clk.h>
+#include <linux/delay.h>
 #include <linux/firmware.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
@@ -29,6 +30,8 @@
 #include "qcom_q6v5.h"
 #include "remoteproc_internal.h"
 
+#define ADSP_DECRYPT_SHUTDOWN_DELAY_MS	100
+
 struct adsp_data {
 	int crash_reason_smem;
 	const char *firmware_name;
@@ -36,6 +39,7 @@ struct adsp_data {
 	unsigned int minidump_id;
 	bool has_aggre2_clk;
 	bool auto_boot;
+	bool decrypt_shutdown;
 
 	char **proxy_pd_names;
 
@@ -65,6 +69,7 @@ struct qcom_adsp {
 	unsigned int minidump_id;
 	int crash_reason_smem;
 	bool has_aggre2_clk;
+	bool decrypt_shutdown;
 	const char *info_name;
 
 	struct completion start_done;
@@ -128,6 +133,19 @@ static void adsp_pds_disable(struct qcom_adsp *adsp, struct device **pds,
 	}
 }
 
+static int adsp_shutdown_poll_decrypt(struct qcom_adsp *adsp)
+{
+	unsigned int retry_num = 50;
+	int ret;
+
+	do {
+		msleep(ADSP_DECRYPT_SHUTDOWN_DELAY_MS);
+		ret = qcom_scm_pas_shutdown(adsp->pas_id);
+	} while (ret == -EINVAL && --retry_num);
+
+	return ret;
+}
+
 static int adsp_unprepare(struct rproc *rproc)
 {
 	struct qcom_adsp *adsp = (struct qcom_adsp *)rproc->priv;
@@ -249,6 +267,9 @@ static int adsp_stop(struct rproc *rproc)
 		dev_err(adsp->dev, "timed out on wait\n");
 
 	ret = qcom_scm_pas_shutdown(adsp->pas_id);
+	if (ret && adsp->decrypt_shutdown)
+		ret = adsp_shutdown_poll_decrypt(adsp);
+
 	if (ret)
 		dev_err(adsp->dev, "failed to shutdown: %d\n", ret);
 
@@ -459,6 +480,7 @@ static int adsp_probe(struct platform_device *pdev)
 	adsp->pas_id = desc->pas_id;
 	adsp->has_aggre2_clk = desc->has_aggre2_clk;
 	adsp->info_name = desc->sysmon_name;
+	adsp->decrypt_shutdown = desc->decrypt_shutdown;
 	platform_set_drvdata(pdev, adsp);
 
 	device_wakeup_enable(adsp->dev);
@@ -877,6 +899,25 @@ static const struct adsp_data sdx55_mpss_resource = {
 	.ssctl_id = 0x22,
 };
 
+static const struct adsp_data sm8450_mpss_resource = {
+	.crash_reason_smem = 421,
+	.firmware_name = "modem.mdt",
+	.pas_id = 4,
+	.minidump_id = 3,
+	.has_aggre2_clk = false,
+	.auto_boot = false,
+	.decrypt_shutdown = true,
+	.proxy_pd_names = (char*[]){
+		"cx",
+		"mss",
+		NULL
+	},
+	.load_state = "modem",
+	.ssr_name = "mpss",
+	.sysmon_name = "modem",
+	.ssctl_id = 0x12,
+};
+
 static const struct of_device_id adsp_of_match[] = {
 	{ .compatible = "qcom,msm8226-adsp-pil", .data = &adsp_resource_init},
 	{ .compatible = "qcom,msm8974-adsp-pil", .data = &adsp_resource_init},
@@ -916,7 +957,7 @@ static const struct of_device_id adsp_of_match[] = {
 	{ .compatible = "qcom,sm8450-adsp-pas", .data = &sm8350_adsp_resource},
 	{ .compatible = "qcom,sm8450-cdsp-pas", .data = &sm8350_cdsp_resource},
 	{ .compatible = "qcom,sm8450-slpi-pas", .data = &sm8350_slpi_resource},
-	{ .compatible = "qcom,sm8450-mpss-pas", .data = &mpss_resource_init},
+	{ .compatible = "qcom,sm8450-mpss-pas", .data = &sm8450_mpss_resource},
 	{ },
 };
 MODULE_DEVICE_TABLE(of, adsp_of_match);
-- 
2.7.4