diff mbox series

[v3,4/5] firmware: qcom_scm: Refactor code to support multiple download mode

Message ID 1679070482-8391-5-git-send-email-quic_mojha@quicinc.com
State New
Headers
Series Refactor to support multiple download mode |

Commit Message

Mukesh Ojha March 17, 2023, 4:28 p.m. UTC 
  Currently on Qualcomm SoC, download_mode is enabled if
CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT is selected.

Refactor the code such that it supports multiple download
modes and drop CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT config
instead, give interface to set the download mode from
module parameter.

Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
---
 drivers/firmware/Kconfig    | 11 ---------
 drivers/firmware/qcom_scm.c | 57 +++++++++++++++++++++++++++++++++++++++------
 2 files changed, 50 insertions(+), 18 deletions(-)
diff mbox series

Patch

diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index b59e304..ff7e9f3 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -215,17 +215,6 @@  config MTK_ADSP_IPC
 config QCOM_SCM
 	tristate
 
-config QCOM_SCM_DOWNLOAD_MODE_DEFAULT
-	bool "Qualcomm download mode enabled by default"
-	depends on QCOM_SCM
-	help
-	  A device with "download mode" enabled will upon an unexpected
-	  warm-restart enter a special debug mode that allows the user to
-	  "download" memory content over USB for offline postmortem analysis.
-	  The feature can be enabled/disabled on the kernel command line.
-
-	  Say Y here to enable "download mode" by default.
-
 config SYSFB
 	bool
 	select BOOT_VESA_SUPPORT
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index eb491da..69f864d 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -20,17 +20,19 @@ 
 #include <linux/clk.h>
 #include <linux/reset-controller.h>
 #include <linux/arm-smccc.h>
+#include <linux/kstrtox.h>
 
 #include "qcom_scm.h"
 
-static bool download_mode = IS_ENABLED(CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT);
-module_param(download_mode, bool, 0);
+static u32 download_mode;
 
 #define SCM_HAS_CORE_CLK	BIT(0)
 #define SCM_HAS_IFACE_CLK	BIT(1)
 #define SCM_HAS_BUS_CLK		BIT(2)
 
 #define QCOM_DOWNLOAD_MODE_MASK 0x30
+#define QCOM_DOWNLOAD_FULLDUMP	0x10
+#define QCOM_DOWNLOAD_NODUMP	0x0
 
 struct qcom_scm {
 	struct device *dev;
@@ -439,8 +441,9 @@  static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
 	return qcom_scm_call_atomic(__scm->dev, &desc, NULL);
 }
 
-static void qcom_scm_set_download_mode(bool enable)
+static void qcom_scm_set_download_mode(u32 download_mode)
 {
+	bool enable = !!download_mode;
 	bool avail;
 	int ret = 0;
 
@@ -452,7 +455,7 @@  static void qcom_scm_set_download_mode(bool enable)
 	} else if (__scm->dload_mode_addr) {
 		ret = qcom_scm_io_update_field(__scm->dload_mode_addr,
 				QCOM_DOWNLOAD_MODE_MASK,
-				enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0);
+				enable ? download_mode : 0);
 	} else {
 		dev_err(__scm->dev,
 			"No available mechanism for setting download mode\n");
@@ -1418,6 +1421,46 @@  static irqreturn_t qcom_scm_irq_handler(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+
+static int get_download_mode(char *buffer, const struct kernel_param *kp)
+{
+	int len;
+
+	if (download_mode == QCOM_DOWNLOAD_FULLDUMP)
+		len = sysfs_emit(buffer, "full\n");
+	else if (download_mode == QCOM_DOWNLOAD_NODUMP)
+		len = sysfs_emit(buffer, "off\n");
+
+	return len;
+}
+
+static int set_download_mode(const char *val, const struct kernel_param *kp)
+{
+	if (!strncmp(val, "full", strlen("full"))) {
+		download_mode = QCOM_DOWNLOAD_FULLDUMP;
+	} else if (!strncmp(val, "off", strlen("off"))) {
+		download_mode = QCOM_DOWNLOAD_NODUMP;
+	} else if (kstrtouint(val, 0, &download_mode) ||
+		   !(download_mode == 0 || download_mode == 1)) {
+		pr_err("unknown download mode\n");
+		return -EINVAL;
+	}
+
+	if (__scm)
+		qcom_scm_set_download_mode(download_mode);
+
+	return 0;
+}
+
+static const struct kernel_param_ops download_mode_param_ops = {
+	.get = get_download_mode,
+	.set = set_download_mode,
+};
+
+module_param_cb(download_mode, &download_mode_param_ops, NULL, 0644);
+MODULE_PARM_DESC(download_mode,
+		 "Download mode: off/full or 0/1 for existing users");
+
 static int qcom_scm_probe(struct platform_device *pdev)
 {
 	struct qcom_scm *scm;
@@ -1511,12 +1554,12 @@  static int qcom_scm_probe(struct platform_device *pdev)
 	__get_convention();
 
 	/*
-	 * If requested enable "download mode", from this point on warmboot
+	 * If "download mode" is requested, from this point on warmboot
 	 * 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);
 
 	return 0;
 }
@@ -1524,7 +1567,7 @@  static int qcom_scm_probe(struct platform_device *pdev)
 static void qcom_scm_shutdown(struct platform_device *pdev)
 {
 	/* Clean shutdown, disable download mode to allow normal restart */
-	qcom_scm_set_download_mode(false);
+	qcom_scm_set_download_mode(QCOM_DOWNLOAD_NODUMP);
 }
 
 static const struct of_device_id qcom_scm_dt_match[] = {