drivers: misc: Add qseecom proxy module

qseecom proxy module serves kernel clients
by providing required ops to smcinvoke and
qseecom drivers  via call back functions
with a minimal framework.

Change-Id: I1974329e4699f72cd1e41fb723acd72959e21ba2
Signed-off-by: Anmolpreet Kaur <quic_anmolpre@quicinc.com>
Signed-off-by: Smita Ghosh <quic_smitag@quicinc.com>

drivers/misc/Kconfig

@@ -512,6 +512,14 @@ config VCPU_STALL_DETECTOR
 
 	  If you do not intend to run this kernel as a guest, say N.
 
+config QSEECOM_PROXY
+	tristate "To enable qseecom proxy driver for kernel client"
+	help
+	 qseecom proxy driver serves the kernel clients by providing
+	 required ops via call back functions with a minimal framework.
+	 These callback functions can be used to start, shutdown and
+	 send commands to the trusted apps.
+
 source "drivers/misc/c2port/Kconfig"
 source "drivers/misc/eeprom/Kconfig"
 source "drivers/misc/cb710/Kconfig"

drivers/misc/Makefile

@@ -62,3 +62,4 @@ obj-$(CONFIG_HI6421V600_IRQ)	+= hi6421v600-irq.o
 obj-$(CONFIG_OPEN_DICE)		+= open-dice.o
 obj-$(CONFIG_VCPU_STALL_DETECTOR)	+= vcpu_stall_detector.o
 obj-$(CONFIG_UID_SYS_STATS)	+= uid_sys_stats.o
+obj-$(CONFIG_QSEECOM_PROXY) 	+= qseecom_proxy.o

drivers/misc/qseecom_proxy.c

@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/printk.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/qseecom_kernel.h>
+#include <linux/of_platform.h>
+#include <linux/mod_devicetable.h>
+
+static struct qseecom_drv_ops qseecom_fun_ops = {0};
+
+int provide_qseecom_kernel_fun_ops(const struct qseecom_drv_ops *ops)
+{
+	if (!ops) {
+		pr_err("ops is NULL\n");
+		return -1;
+	}
+	qseecom_fun_ops = *ops;
+	pr_debug("QSEECOM proxy Ready to be served\n");
+	return 0;
+}
+EXPORT_SYMBOL(provide_qseecom_kernel_fun_ops);
+
+int qseecom_start_app(struct qseecom_handle **handle,
+					char *app_name, uint32_t size)
+{
+	int32_t ret = -1;
+
+	/* start the application */
+	if (qseecom_fun_ops.qseecom_start_app) {
+		ret = qseecom_fun_ops.qseecom_start_app(handle, app_name, size);
+		if (ret != 0)
+			pr_err("%s: Start app -%s failed\n", __func__, app_name);
+	} else {
+		pr_err_ratelimited("Qseecom driver is not up yet\n");
+		ret = -EAGAIN;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(qseecom_start_app);
+
+
+int qseecom_shutdown_app(struct qseecom_handle **handle)
+{
+	int32_t ret = -1;
+
+	/* shutdown the application */
+	if (qseecom_fun_ops.qseecom_shutdown_app) {
+		ret = qseecom_fun_ops.qseecom_shutdown_app(handle);
+		if (ret != 0)
+			pr_err("%s: qseecom shutdown app failed with ret = %d\n", __func__, ret);
+	} else {
+		pr_err_ratelimited("Qseecom driver is not up yet\n");
+		ret = -EAGAIN;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(qseecom_shutdown_app);
+
+
+int qseecom_send_command(struct qseecom_handle *handle, void *send_buf,
+	uint32_t sbuf_len, void *resp_buf, uint32_t rbuf_len)
+{
+	int32_t ret = -1;
+
+	/* send command to application*/
+	if (qseecom_fun_ops.qseecom_send_command) {
+		ret = qseecom_fun_ops.qseecom_send_command(handle, send_buf, sbuf_len,
+					resp_buf, rbuf_len);
+		if (ret != 0)
+			pr_err("%s: qseecom send command failed with ret = %d\n", __func__, ret);
+	} else {
+		pr_err_ratelimited("Qseecom driver is not up yet\n");
+		ret = -EAGAIN;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(qseecom_send_command);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Qseecom proxy driver");

include/linux/qseecom_kernel.h

@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef __QSEECOM_KERNEL_H_
+#define __QSEECOM_KERNEL_H_
+
+#include <linux/types.h>
+
+
+#define QSEECOM_ALIGN_SIZE	0x40
+#define QSEECOM_ALIGN_MASK	(QSEECOM_ALIGN_SIZE - 1)
+#define QSEECOM_ALIGN(x)	\
+	((x + QSEECOM_ALIGN_MASK) & (~QSEECOM_ALIGN_MASK))
+
+/*
+ * struct qseecom_handle -
+ *      Handle to the qseecom device for kernel clients
+ * @dev  - qseecom_dev_handle
+ * @sbuf - shared buffer pointer
+ * @sbbuf_len - shared buffer size
+ */
+struct qseecom_handle {
+	void *dev; /* in/out */
+	unsigned char *sbuf; /* in/out */
+	uint32_t sbuf_len; /* in/out */
+};
+
+int qseecom_start_app(struct qseecom_handle **handle,
+			char *app_name,
+			uint32_t size);
+int qseecom_shutdown_app(struct qseecom_handle **handle);
+int qseecom_send_command(struct qseecom_handle *handle,
+			void *send_buf, uint32_t sbuf_len,
+			void *resp_buf, uint32_t rbuf_len);
+
+#if IS_ENABLED(CONFIG_QSEECOM_PROXY)
+struct qseecom_drv_ops {
+	int (*qseecom_send_command)(struct qseecom_handle *handle, void *send_buf,
+				uint32_t sbuf_len, void *resp_buf, uint32_t rbuf_len);
+	int (*qseecom_start_app)(struct qseecom_handle **handle,
+				char *app_name, uint32_t size);
+	int (*qseecom_shutdown_app)(struct qseecom_handle **handle);
+};
+
+int provide_qseecom_kernel_fun_ops(const struct qseecom_drv_ops *ops);
+#endif
+
+#endif /* __QSEECOM_KERNEL_H_ */