drivers/misc/mic/cosm/cosm_debugfs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Intel MIC Platform Software Stack (MPSS)
   4  *
   5  * Copyright(c) 2015 Intel Corporation.
   6  *
   7  * Intel MIC Coprocessor State Management (COSM) Driver
   8  */
   9
  10 #include <linux/debugfs.h>
  11 #include <linux/slab.h>
  12 #include <linux/io.h>
  13 #include "cosm_main.h"
  14
  15 /* Debugfs parent dir */
  16 static struct dentry *cosm_dbg;
  17
  18 /**
  19  * log_buf_show - Display MIC kernel log buffer
  20  *
  21  * log_buf addr/len is read from System.map by user space
  22  * and populated in sysfs entries.
  23  */
  24 static int log_buf_show(struct seq_file *s, void *unused)
  25 {
  26         void __iomem *log_buf_va;
  27         int __iomem *log_buf_len_va;
  28         struct cosm_device *cdev = s->private;
  29         void *kva;
  30         int size;
  31         u64 aper_offset;
  32
  33         if (!cdev || !cdev->log_buf_addr || !cdev->log_buf_len)
  34                 goto done;
  35
  36         mutex_lock(&cdev->cosm_mutex);
  37         switch (cdev->state) {
  38         case MIC_BOOTING:
  39         case MIC_ONLINE:
  40         case MIC_SHUTTING_DOWN:
  41                 break;
  42         default:
  43                 goto unlock;
  44         }
  45
  46         /*
  47          * Card kernel will never be relocated and any kernel text/data mapping
  48          * can be translated to phys address by subtracting __START_KERNEL_map.
  49          */
  50         aper_offset = (u64)cdev->log_buf_len - __START_KERNEL_map;
  51         log_buf_len_va = cdev->hw_ops->aper(cdev)->va + aper_offset;
  52         aper_offset = (u64)cdev->log_buf_addr - __START_KERNEL_map;
  53         log_buf_va = cdev->hw_ops->aper(cdev)->va + aper_offset;
  54
  55         size = ioread32(log_buf_len_va);
  56         kva = kmalloc(size, GFP_KERNEL);
  57         if (!kva)
  58                 goto unlock;
  59
  60         memcpy_fromio(kva, log_buf_va, size);
  61         seq_write(s, kva, size);
  62         kfree(kva);
  63 unlock:
  64         mutex_unlock(&cdev->cosm_mutex);
  65 done:
  66         return 0;
  67 }
  68
  69 DEFINE_SHOW_ATTRIBUTE(log_buf);
  70
  71 /**
  72  * force_reset_show - Force MIC reset
  73  *
  74  * Invokes the force_reset COSM bus op instead of the standard reset
  75  * op in case a force reset of the MIC device is required
  76  */
  77 static int force_reset_show(struct seq_file *s, void *pos)
  78 {
  79         struct cosm_device *cdev = s->private;
  80
  81         cosm_stop(cdev, true);
  82         return 0;
  83 }
  84
  85 DEFINE_SHOW_ATTRIBUTE(force_reset);
  86
  87 void cosm_create_debug_dir(struct cosm_device *cdev)
  88 {
  89         char name[16];
  90
  91         if (!cosm_dbg)
  92                 return;
  93
  94         scnprintf(name, sizeof(name), "mic%d", cdev->index);
  95         cdev->dbg_dir = debugfs_create_dir(name, cosm_dbg);
  96
  97         debugfs_create_file("log_buf", 0444, cdev->dbg_dir, cdev,
  98                             &log_buf_fops);
  99         debugfs_create_file("force_reset", 0444, cdev->dbg_dir, cdev,
 100                             &force_reset_fops);
 101 }
 102
 103 void cosm_delete_debug_dir(struct cosm_device *cdev)
 104 {
 105         debugfs_remove_recursive(cdev->dbg_dir);
 106 }
 107
 108 void cosm_init_debugfs(void)
 109 {
 110         cosm_dbg = debugfs_create_dir(KBUILD_MODNAME, NULL);
 111 }
 112
 113 void cosm_exit_debugfs(void)
 114 {
 115         debugfs_remove(cosm_dbg);
 116 }