arch/x86/platform/atom/punit_atom_debug.c

   1 /*
   2  * Intel SOC Punit device state debug driver
   3  * Punit controls power management for North Complex devices (Graphics
   4  * blocks, Image Signal Processing, video processing, display, DSP etc.)
   5  *
   6  * Copyright (c) 2015, Intel Corporation.
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms and conditions of the GNU General Public License,
  10  * version 2, as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/device.h>
  22 #include <linux/debugfs.h>
  23 #include <linux/seq_file.h>
  24 #include <linux/io.h>
  25 #include <asm/cpu_device_id.h>
  26 #include <asm/iosf_mbi.h>
  27
  28 /* Side band Interface port */
  29 #define PUNIT_PORT              0x04
  30 /* Power gate status reg */
  31 #define PWRGT_STATUS            0x61
  32 /* Subsystem config/status Video processor */
  33 #define VED_SS_PM0              0x32
  34 /* Subsystem config/status ISP (Image Signal Processor) */
  35 #define ISP_SS_PM0              0x39
  36 /* Subsystem config/status Input/output controller */
  37 #define MIO_SS_PM               0x3B
  38 /* Shift bits for getting status for video, isp and i/o */
  39 #define SSS_SHIFT               24
  40 /* Shift bits for getting status for graphics rendering */
  41 #define RENDER_POS              0
  42 /* Shift bits for getting status for media control */
  43 #define MEDIA_POS               2
  44 /* Shift bits for getting status for Valley View/Baytrail display */
  45 #define VLV_DISPLAY_POS         6
  46 /* Subsystem config/status display for Cherry Trail SOC */
  47 #define CHT_DSP_SSS             0x36
  48 /* Shift bits for getting status for display */
  49 #define CHT_DSP_SSS_POS         16
  50
  51 struct punit_device {
  52         char *name;
  53         int reg;
  54         int sss_pos;
  55 };
  56
  57 static const struct punit_device punit_device_byt[] = {
  58         { "GFX RENDER", PWRGT_STATUS,   RENDER_POS },
  59         { "GFX MEDIA",  PWRGT_STATUS,   MEDIA_POS },
  60         { "DISPLAY",    PWRGT_STATUS,   VLV_DISPLAY_POS },
  61         { "VED",        VED_SS_PM0,     SSS_SHIFT },
  62         { "ISP",        ISP_SS_PM0,     SSS_SHIFT },
  63         { "MIO",        MIO_SS_PM,      SSS_SHIFT },
  64         { NULL }
  65 };
  66
  67 static const struct punit_device punit_device_cht[] = {
  68         { "GFX RENDER", PWRGT_STATUS,   RENDER_POS },
  69         { "GFX MEDIA",  PWRGT_STATUS,   MEDIA_POS },
  70         { "DISPLAY",    CHT_DSP_SSS,    CHT_DSP_SSS_POS },
  71         { "VED",        VED_SS_PM0,     SSS_SHIFT },
  72         { "ISP",        ISP_SS_PM0,     SSS_SHIFT },
  73         { "MIO",        MIO_SS_PM,      SSS_SHIFT },
  74         { NULL }
  75 };
  76
  77 static const char * const dstates[] = {"D0", "D0i1", "D0i2", "D0i3"};
  78
  79 static int punit_dev_state_show(struct seq_file *seq_file, void *unused)
  80 {
  81         u32 punit_pwr_status;
  82         struct punit_device *punit_devp = seq_file->private;
  83         int index;
  84         int status;
  85
  86         seq_puts(seq_file, "\n\nPUNIT NORTH COMPLEX DEVICES :\n");
  87         while (punit_devp->name) {
  88                 status = iosf_mbi_read(PUNIT_PORT, BT_MBI_PMC_READ,
  89                                        punit_devp->reg,
  90                                        &punit_pwr_status);
  91                 if (status) {
  92                         seq_printf(seq_file, "%9s : Read Failed\n",
  93                                    punit_devp->name);
  94                 } else  {
  95                         index = (punit_pwr_status >> punit_devp->sss_pos) & 3;
  96                         seq_printf(seq_file, "%9s : %s\n", punit_devp->name,
  97                                    dstates[index]);
  98                 }
  99                 punit_devp++;
 100         }
 101
 102         return 0;
 103 }
 104
 105 static int punit_dev_state_open(struct inode *inode, struct file *file)
 106 {
 107         return single_open(file, punit_dev_state_show, inode->i_private);
 108 }
 109
 110 static const struct file_operations punit_dev_state_ops = {
 111         .open           = punit_dev_state_open,
 112         .read           = seq_read,
 113         .llseek         = seq_lseek,
 114         .release        = single_release,
 115 };
 116
 117 static struct dentry *punit_dbg_file;
 118
 119 static int punit_dbgfs_register(struct punit_device *punit_device)
 120 {
 121         static struct dentry *dev_state;
 122
 123         punit_dbg_file = debugfs_create_dir("punit_atom", NULL);
 124         if (!punit_dbg_file)
 125                 return -ENXIO;
 126
 127         dev_state = debugfs_create_file("dev_power_state", S_IFREG | S_IRUGO,
 128                                         punit_dbg_file, punit_device,
 129                                         &punit_dev_state_ops);
 130         if (!dev_state) {
 131                 pr_err("punit_dev_state register failed\n");
 132                 debugfs_remove(punit_dbg_file);
 133                 return -ENXIO;
 134         }
 135
 136         return 0;
 137 }
 138
 139 static void punit_dbgfs_unregister(void)
 140 {
 141         debugfs_remove_recursive(punit_dbg_file);
 142 }
 143
 144 #define ICPU(model, drv_data) \
 145         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT,\
 146           (kernel_ulong_t)&drv_data }
 147
 148 static const struct x86_cpu_id intel_punit_cpu_ids[] = {
 149         ICPU(55, punit_device_byt), /* Valleyview, Bay Trail */
 150         ICPU(76, punit_device_cht), /* Braswell, Cherry Trail */
 151         {}
 152 };
 153
 154 MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
 155
 156 static int __init punit_atom_debug_init(void)
 157 {
 158         const struct x86_cpu_id *id;
 159         int ret;
 160
 161         id = x86_match_cpu(intel_punit_cpu_ids);
 162         if (!id)
 163                 return -ENODEV;
 164
 165         ret = punit_dbgfs_register((struct punit_device *)id->driver_data);
 166         if (ret < 0)
 167                 return ret;
 168
 169         return 0;
 170 }
 171
 172 static void __exit punit_atom_debug_exit(void)
 173 {
 174         punit_dbgfs_unregister();
 175 }
 176
 177 module_init(punit_atom_debug_init);
 178 module_exit(punit_atom_debug_exit);
 179
 180 MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>");
 181 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
 182 MODULE_DESCRIPTION("Driver for Punit devices states debugging");
 183 MODULE_LICENSE("GPL v2");