firmware: xilinx: Add debugfs interface (b3217252) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/firmware/xilinx/Kconfig

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Original line number	Diff line number	Diff line
		@@ -13,4 +13,11 @@ config ZYNQMP_FIRMWARE
		Say yes to enable ZynqMP firmware interface driver.
		If in doubt, say N.

		config ZYNQMP_FIRMWARE_DEBUG
		bool "Enable Xilinx Zynq MPSoC firmware debug APIs"
		depends on ZYNQMP_FIRMWARE && DEBUG_FS
		help
		Say yes to enable ZynqMP firmware interface debug APIs.
		If in doubt, say N.

		endmenu

drivers/firmware/xilinx/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -2,3 +2,4 @@
		# Makefile for Xilinx firmwares

		obj-$(CONFIG_ZYNQMP_FIRMWARE) += zynqmp.o
		obj-$(CONFIG_ZYNQMP_FIRMWARE_DEBUG) += zynqmp-debug.o

drivers/firmware/xilinx/zynqmp-debug.c

0 → 100644

+222 −0

Original line number	Diff line number	Diff line
		// 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),
		};

		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;

		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;
		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);
		}

drivers/firmware/xilinx/zynqmp-debug.h

0 → 100644

+24 −0

Original line number	Diff line number	Diff line
		/* SPDX-License-Identifier: GPL-2.0 */
		/*
		* Xilinx Zynq MPSoC Firmware layer
		*
		* Copyright (C) 2014-2018 Xilinx
		*
		* Michal Simek <michal.simek@xilinx.com>
		* Davorin Mista <davorin.mista@aggios.com>
		* Jolly Shah <jollys@xilinx.com>
		* Rajan Vaja <rajanv@xilinx.com>
		*/

		#ifndef __FIRMWARE_ZYNQMP_DEBUG_H__
		#define __FIRMWARE_ZYNQMP_DEBUG_H__

		#if IS_REACHABLE(CONFIG_ZYNQMP_FIRMWARE_DEBUG)
		void zynqmp_pm_api_debugfs_init(void);
		void zynqmp_pm_api_debugfs_exit(void);
		#else
		static inline void zynqmp_pm_api_debugfs_init(void) { }
		static inline void zynqmp_pm_api_debugfs_exit(void) { }
		#endif

		#endif /* __FIRMWARE_ZYNQMP_DEBUG_H__ */

drivers/firmware/xilinx/zynqmp.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -21,6 +21,7 @@
		#include <linux/uaccess.h>

		#include <linux/firmware/xlnx-zynqmp.h>
		#include "zynqmp-debug.h"

		/**
		* zynqmp_pm_ret_code() - Convert PMU-FW error codes to Linux error codes
		@@ -493,11 +494,15 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
		pr_info("%s Trustzone version v%d.%d\n", __func__,
		pm_tz_version >> 16, pm_tz_version & 0xFFFF);

		zynqmp_pm_api_debugfs_init();

		return of_platform_populate(dev->of_node, NULL, NULL, dev);
		}

		static int zynqmp_firmware_remove(struct platform_device *pdev)
		{
		zynqmp_pm_api_debugfs_exit();

		return 0;
		}