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From:   Robert Marko <robimarko@gmail.com>
To:     agross@kernel.org, andersson@kernel.orgm, konrad.dybcio@linaro.org,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
        quic_srichara@quicinc.com
Cc:     Robert Marko <robimarko@gmail.com>
Subject: [PATCH 1/2] firmware: qcom: scm: Add SDI disable support
Date:   Thu, 18 May 2023 15:59:44 +0200
Message-Id: <20230518135945.2248451-1-robimarko@gmail.com>
MIME-Version: 1.0
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Some SoC-s like IPQ5018 require SDI(Secure Debug Image) to be disabled
before trying to reboot, otherwise board will just hang after reboot has
been issued via PSCI.

So, provide a call to SCM that allows disabling it.

Signed-off-by: Robert Marko <robimarko@gmail.com>
---
 drivers/firmware/qcom_scm.c | 23 +++++++++++++++++++++++
 drivers/firmware/qcom_scm.h |  1 +
 2 files changed, 24 insertions(+)

diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index fde33acd46b7..bdc9324d4e62 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -407,6 +407,29 @@ int qcom_scm_set_remote_state(u32 state, u32 id)
 }
 EXPORT_SYMBOL(qcom_scm_set_remote_state);
 
+static int qcom_scm_disable_sdi(void)
+{
+	int ret;
+	struct qcom_scm_desc desc = {
+		.svc = QCOM_SCM_SVC_BOOT,
+		.cmd = QCOM_SCM_BOOT_SDI_CONFIG,
+		.args[0] = 1, /* Disable watchdog debug */
+		.args[1] = 0, /* Disable SDI */
+		.arginfo = QCOM_SCM_ARGS(2),
+		.owner = ARM_SMCCC_OWNER_SIP,
+	};
+	struct qcom_scm_res res;
+
+	ret = qcom_scm_clk_enable();
+	if (ret)
+		return ret;
+	ret = qcom_scm_call(__scm->dev, &desc, &res);
+
+	qcom_scm_clk_disable();
+
+	return ret ? : res.result[0];
+}
+
 static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
 {
 	struct qcom_scm_desc desc = {
diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
index e6e512bd57d1..7b68fa820495 100644
--- a/drivers/firmware/qcom_scm.h
+++ b/drivers/firmware/qcom_scm.h
@@ -80,6 +80,7 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
 #define QCOM_SCM_SVC_BOOT		0x01
 #define QCOM_SCM_BOOT_SET_ADDR		0x01
 #define QCOM_SCM_BOOT_TERMINATE_PC	0x02
+#define QCOM_SCM_BOOT_SDI_CONFIG	0x09
 #define QCOM_SCM_BOOT_SET_DLOAD_MODE	0x10
 #define QCOM_SCM_BOOT_SET_ADDR_MC	0x11
 #define QCOM_SCM_BOOT_SET_REMOTE_STATE	0x0a
-- 
2.40.1