Merge tag 'zynqmp-soc-for-v4.20-v2' of https://github.com/Xilinx/linux-xlnx into next/drivers

arm64: zynqmp: SoC changes for v4.20

- Adding firmware API for SoC with debugfs interface
  Firmware driver communicates to Platform Management Unit (PMU) by using
  SMC instructions routed to Arm Trusted Firmware (ATF). Initial version
  adds support for base firmware driver with query and clock APIs.

  EEMI spec is available here:
  https://www.xilinx.com/support/documentation/user_guides/ug1200-eemi-api.pdf

* tag 'zynqmp-soc-for-v4.20-v2' of https://github.com/Xilinx/linux-xlnx:
  firmware: xilinx: Add debugfs for query data API
  firmware: xilinx: Add debugfs interface
  firmware: xilinx: Add clock APIs
  firmware: xilinx: Add query data API
  firmware: xilinx: Add Zynqmp firmware driver
  dt-bindings: firmware: Add bindings for ZynqMP firmware

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 250 insertions, 0 deletions

diff --git a/drivers/firmware/xilinx/zynqmp-debug.c b/drivers/firmware/xilinx/zynqmp-debug.c
new file mode 100644
index 000000000000..2771df6df379
--- /dev/null
+++ b/drivers/firmware/xilinx/zynqmp-debug.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx Zynq MPSoC Firmware layer for debugfs APIs
+ *
+ *  Copyright (C) 2014-2018 Xilinx, Inc.
+ *
+ *  Michal Simek <michal.simek@xilinx.com>
+ *  Davorin Mista <davorin.mista@aggios.com>
+ *  Jolly Shah <jollys@xilinx.com>
+ *  Rajan Vaja <rajanv@xilinx.com>
+ */
+
+#include <linux/compiler.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+
+#include <linux/firmware/xlnx-zynqmp.h>
+#include "zynqmp-debug.h"
+
+#define PM_API_NAME_LEN			50
+
+struct pm_api_info {
+	u32 api_id;
+	char api_name[PM_API_NAME_LEN];
+	char api_name_len;
+};
+
+static char debugfs_buf[PAGE_SIZE];
+
+#define PM_API(id)		 {id, #id, strlen(#id)}
+static struct pm_api_info pm_api_list[] = {
+	PM_API(PM_GET_API_VERSION),
+	PM_API(PM_QUERY_DATA),
+};
+
+struct dentry *firmware_debugfs_root;
+
+/**
+ * zynqmp_pm_argument_value() - Extract argument value from a PM-API request
+ * @arg:	Entered PM-API argument in string format
+ *
+ * Return: Argument value in unsigned integer format on success
+ *	   0 otherwise
+ */
+static u64 zynqmp_pm_argument_value(char *arg)
+{
+	u64 value;
+
+	if (!arg)
+		return 0;
+
+	if (!kstrtou64(arg, 0, &value))
+		return value;
+
+	return 0;
+}
+
+/**
+ * get_pm_api_id() - Extract API-ID from a PM-API request
+ * @pm_api_req:		Entered PM-API argument in string format
+ * @pm_id:		API-ID
+ *
+ * Return: 0 on success else error code
+ */
+static int get_pm_api_id(char *pm_api_req, u32 *pm_id)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(pm_api_list) ; i++) {
+		if (!strncasecmp(pm_api_req, pm_api_list[i].api_name,
+				 pm_api_list[i].api_name_len)) {
+			*pm_id = pm_api_list[i].api_id;
+			break;
+		}
+	}
+
+	/* If no name was entered look for PM-API ID instead */
+	if (i == ARRAY_SIZE(pm_api_list) && kstrtouint(pm_api_req, 10, pm_id))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int process_api_request(u32 pm_id, u64 *pm_api_arg, u32 *pm_api_ret)
+{
+	const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
+	u32 pm_api_version;
+	int ret;
+	struct zynqmp_pm_query_data qdata = {0};
+
+	if (!eemi_ops)
+		return -ENXIO;
+
+	switch (pm_id) {
+	case PM_GET_API_VERSION:
+		ret = eemi_ops->get_api_version(&pm_api_version);
+		sprintf(debugfs_buf, "PM-API Version = %d.%d\n",
+			pm_api_version >> 16, pm_api_version & 0xffff);
+		break;
+	case PM_QUERY_DATA:
+		qdata.qid = pm_api_arg[0];
+		qdata.arg1 = pm_api_arg[1];
+		qdata.arg2 = pm_api_arg[2];
+		qdata.arg3 = pm_api_arg[3];
+
+		ret = eemi_ops->query_data(qdata, pm_api_ret);
+		if (ret)
+			break;
+
+		switch (qdata.qid) {
+		case PM_QID_CLOCK_GET_NAME:
+			sprintf(debugfs_buf, "Clock name = %s\n",
+				(char *)pm_api_ret);
+			break;
+		case PM_QID_CLOCK_GET_FIXEDFACTOR_PARAMS:
+			sprintf(debugfs_buf, "Multiplier = %d, Divider = %d\n",
+				pm_api_ret[1], pm_api_ret[2]);
+			break;
+		default:
+			sprintf(debugfs_buf,
+				"data[0] = 0x%08x\ndata[1] = 0x%08x\n data[2] = 0x%08x\ndata[3] = 0x%08x\n",
+				pm_api_ret[0], pm_api_ret[1],
+				pm_api_ret[2], pm_api_ret[3]);
+		}
+		break;
+	default:
+		sprintf(debugfs_buf, "Unsupported PM-API request\n");
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+/**
+ * zynqmp_pm_debugfs_api_write() - debugfs write function
+ * @file:	User file
+ * @ptr:	User entered PM-API string
+ * @len:	Length of the userspace buffer
+ * @off:	Offset within the file
+ *
+ * Used for triggering pm api functions by writing
+ * echo <pm_api_id>	> /sys/kernel/debug/zynqmp_pm/power or
+ * echo <pm_api_name>	> /sys/kernel/debug/zynqmp_pm/power
+ *
+ * Return: Number of bytes copied if PM-API request succeeds,
+ *	   the corresponding error code otherwise
+ */
+static ssize_t zynqmp_pm_debugfs_api_write(struct file *file,
+					   const char __user *ptr, size_t len,
+					   loff_t *off)
+{
+	char *kern_buff, *tmp_buff;
+	char *pm_api_req;
+	u32 pm_id = 0;
+	u64 pm_api_arg[4] = {0, 0, 0, 0};
+	/* Return values from PM APIs calls */
+	u32 pm_api_ret[4] = {0, 0, 0, 0};
+
+	int ret;
+	int i = 0;
+
+	strcpy(debugfs_buf, "");
+
+	if (*off != 0 || len == 0)
+		return -EINVAL;
+
+	kern_buff = kzalloc(len, GFP_KERNEL);
+	if (!kern_buff)
+		return -ENOMEM;
+
+	tmp_buff = kern_buff;
+
+	ret = strncpy_from_user(kern_buff, ptr, len);
+	if (ret < 0) {
+		ret = -EFAULT;
+		goto err;
+	}
+
+	/* Read the API name from a user request */
+	pm_api_req = strsep(&kern_buff, " ");
+
+	ret = get_pm_api_id(pm_api_req, &pm_id);
+	if (ret < 0)
+		goto err;
+
+	/* Read node_id and arguments from the PM-API request */
+	pm_api_req = strsep(&kern_buff, " ");
+	while ((i < ARRAY_SIZE(pm_api_arg)) && pm_api_req) {
+		pm_api_arg[i++] = zynqmp_pm_argument_value(pm_api_req);
+		pm_api_req = strsep(&kern_buff, " ");
+	}
+
+	ret = process_api_request(pm_id, pm_api_arg, pm_api_ret);
+
+err:
+	kfree(tmp_buff);
+	if (ret)
+		return ret;
+
+	return len;
+}
+
+/**
+ * zynqmp_pm_debugfs_api_read() - debugfs read function
+ * @file:	User file
+ * @ptr:	Requested pm_api_version string
+ * @len:	Length of the userspace buffer
+ * @off:	Offset within the file
+ *
+ * Return: Length of the version string on success
+ *	   else error code
+ */
+static ssize_t zynqmp_pm_debugfs_api_read(struct file *file, char __user *ptr,
+					  size_t len, loff_t *off)
+{
+	return simple_read_from_buffer(ptr, len, off, debugfs_buf,
+				       strlen(debugfs_buf));
+}
+
+/* Setup debugfs fops */
+static const struct file_operations fops_zynqmp_pm_dbgfs = {
+	.owner = THIS_MODULE,
+	.write = zynqmp_pm_debugfs_api_write,
+	.read = zynqmp_pm_debugfs_api_read,
+};
+
+/**
+ * zynqmp_pm_api_debugfs_init - Initialize debugfs interface
+ *
+ * Return:	None
+ */
+void zynqmp_pm_api_debugfs_init(void)
+{
+	/* Initialize debugfs interface */
+	firmware_debugfs_root = debugfs_create_dir("zynqmp-firmware", NULL);
+	debugfs_create_file("pm", 0660, firmware_debugfs_root, NULL,
+			    &fops_zynqmp_pm_dbgfs);
+}
+
+/**
+ * zynqmp_pm_api_debugfs_exit - Remove debugfs interface
+ *
+ * Return:	None
+ */
+void zynqmp_pm_api_debugfs_exit(void)
+{
+	debugfs_remove_recursive(firmware_debugfs_root);
+}