diff options
Diffstat (limited to 'drivers/firmware/xilinx/zynqmp-debug.c')
| -rw-r--r-- | drivers/firmware/xilinx/zynqmp-debug.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/drivers/firmware/xilinx/zynqmp-debug.c b/drivers/firmware/xilinx/zynqmp-debug.c new file mode 100644 index 000000000..99606b349 --- /dev/null +++ b/drivers/firmware/xilinx/zynqmp-debug.c @@ -0,0 +1,239 @@ +// 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), +}; + +static 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) +{ + u32 pm_api_version; + int ret; + struct zynqmp_pm_query_data qdata = {0}; + + switch (pm_id) { + case PM_GET_API_VERSION: + ret = zynqmp_pm_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 = zynqmp_pm_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 <= 1 || len > PAGE_SIZE - 1) + return -EINVAL; + + kern_buff = memdup_user_nul(ptr, len); + if (IS_ERR(kern_buff)) + return PTR_ERR(kern_buff); + tmp_buff = kern_buff; + + /* 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); +} |