linux-kernel - [PATCH ] firmware: qcom: scm: Disable SDI and write no dump to download mode register

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Message-ID: <20240705120623.1424931-1-quic_mojha@quicinc.com>
Date: Fri, 5 Jul 2024 17:36:23 +0530
From: Mukesh Ojha <quic_mojha@...cinc.com>
To: <andersson@...nel.org>, <konrad.dybcio@...aro.org>
CC: <linux-arm-msm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        "Mukesh
 Ojha" <quic_mojha@...cinc.com>
Subject: [PATCH ] firmware: qcom: scm: Disable SDI and write no dump to download mode register

SDI is enabled for most of the Qualcomm SoCs and as per commit
ff4aa3bc9825 ("firmware: qcom_scm: disable SDI if required")
it was recommended to disable SDI by mentioning it in device tree

However, for some cases download mode tcsr register already configured
from boot firmware to collect dumps and in such cases if download
mode is set to zero(nodump mode) from kernel side and SDI is disabled
via means of mentioning it in device tree we could end up with dump
collection.

To disable complete dump collection mode, SDI and dload mode register
need to be set no dump mode.

Signed-off-by: Mukesh Ojha <quic_mojha@...cinc.com>
---
 drivers/firmware/qcom/qcom_scm.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
index 00c379a3cceb..2e10f75a9cfd 100644
--- a/drivers/firmware/qcom/qcom_scm.c
+++ b/drivers/firmware/qcom/qcom_scm.c
@@ -1954,14 +1954,12 @@ static int qcom_scm_probe(struct platform_device *pdev)
 	 * will cause the boot stages to enter download mode, unless
 	 * disabled below by a clean shutdown/reboot.
 	 */
-	if (download_mode)
-		qcom_scm_set_download_mode(true);
-
+	qcom_scm_set_download_mode(download_mode ? true : false);
 
 	/*
 	 * Disable SDI if indicated by DT that it is enabled by default.
 	 */
-	if (of_property_read_bool(pdev->dev.of_node, "qcom,sdi-enabled"))
+	if (of_property_read_bool(pdev->dev.of_node, "qcom,sdi-enabled") || !download_mode)
 		qcom_scm_disable_sdi();
 
 	ret = of_reserved_mem_device_init(__scm->dev);
-- 
2.34.1