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/intel-family.h>
  27 #include <asm/iosf_mbi.h>
  28
  29 /* Subsystem config/status Video processor */
  30 #define VED_SS_PM0              0x32
  31 /* Subsystem config/status ISP (Image Signal Processor) */
  32 #define ISP_SS_PM0              0x39
  33 /* Subsystem config/status Input/output controller */
  34 #define MIO_SS_PM               0x3B
  35 /* Shift bits for getting status for video, isp and i/o */
  36 #define SSS_SHIFT               24
  37
  38 /* Power gate status reg */
  39 #define PWRGT_STATUS            0x61
  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
  47 /* Subsystem config/status display for Cherry Trail SOC */
  48 #define CHT_DSP_SSS             0x36
  49 /* Shift bits for getting status for display */
  50 #define CHT_DSP_SSS_POS         16
  51
  52 struct punit_device {
  53         char *name;
  54         int reg;
  55         int sss_pos;
  56 };
  57
  58 static const struct punit_device punit_device_tng[] = {
  59         { "DISPLAY",    CHT_DSP_SSS,    SSS_SHIFT },
  60         { "VED",        VED_SS_PM0,     SSS_SHIFT },
  61         { "ISP",        ISP_SS_PM0,     SSS_SHIFT },
  62         { "MIO",        MIO_SS_PM,      SSS_SHIFT },
  63         { NULL }
  64 };
  65
  66 static const struct punit_device punit_device_byt[] = {
  67         { "GFX RENDER", PWRGT_STATUS,   RENDER_POS },
  68         { "GFX MEDIA",  PWRGT_STATUS,   MEDIA_POS },
  69         { "DISPLAY",    PWRGT_STATUS,   VLV_DISPLAY_POS },
  70         { "VED",        VED_SS_PM0,     SSS_SHIFT },
  71         { "ISP",        ISP_SS_PM0,     SSS_SHIFT },
  72         { "MIO",        MIO_SS_PM,      SSS_SHIFT },
  73         { NULL }
  74 };
  75
  76 static const struct punit_device punit_device_cht[] = {
  77         { "GFX RENDER", PWRGT_STATUS,   RENDER_POS },
  78         { "GFX MEDIA",  PWRGT_STATUS,   MEDIA_POS },
  79         { "DISPLAY",    CHT_DSP_SSS,    CHT_DSP_SSS_POS },
  80         { "VED",        VED_SS_PM0,     SSS_SHIFT },
  81         { "ISP",        ISP_SS_PM0,     SSS_SHIFT },
  82         { "MIO",        MIO_SS_PM,      SSS_SHIFT },
  83         { NULL }
  84 };
  85
  86 static const char * const dstates[] = {"D0", "D0i1", "D0i2", "D0i3"};
  87
  88 static int punit_dev_state_show(struct seq_file *seq_file, void *unused)
  89 {
  90         u32 punit_pwr_status;
  91         struct punit_device *punit_devp = seq_file->private;
  92         int index;
  93         int status;
  94
  95         seq_puts(seq_file, "\n\nPUNIT NORTH COMPLEX DEVICES :\n");
  96         while (punit_devp->name) {
  97                 status = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ,
  98                                        punit_devp->reg, &punit_pwr_status);
  99                 if (status) {
 100                         seq_printf(seq_file, "%9s : Read Failed\n",
 101                                    punit_devp->name);
 102                 } else  {
 103                         index = (punit_pwr_status >> punit_devp->sss_pos) & 3;
 104                         seq_printf(seq_file, "%9s : %s\n", punit_devp->name,
 105                                    dstates[index]);
 106                 }
 107                 punit_devp++;
 108         }
 109
 110         return 0;
 111 }
 112 DEFINE_SHOW_ATTRIBUTE(punit_dev_state);
 113
 114 static struct dentry *punit_dbg_file;
 115
 116 static int punit_dbgfs_register(struct punit_device *punit_device)
 117 {
 118         struct dentry *dev_state;
 119
 120         punit_dbg_file = debugfs_create_dir("punit_atom", NULL);
 121         if (!punit_dbg_file)
 122                 return -ENXIO;
 123
 124         dev_state = debugfs_create_file("dev_power_state", 0444,
 125                                         punit_dbg_file, punit_device,
 126                                         &punit_dev_state_fops);
 127         if (!dev_state) {
 128                 pr_err("punit_dev_state register failed\n");
 129                 debugfs_remove(punit_dbg_file);
 130                 return -ENXIO;
 131         }
 132
 133         return 0;
 134 }
 135
 136 static void punit_dbgfs_unregister(void)
 137 {
 138         debugfs_remove_recursive(punit_dbg_file);
 139 }
 140
 141 #define ICPU(model, drv_data) \
 142         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT,\
 143           (kernel_ulong_t)&drv_data }
 144
 145 static const struct x86_cpu_id intel_punit_cpu_ids[] = {
 146         ICPU(INTEL_FAM6_ATOM_SILVERMONT, punit_device_byt),
 147         ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID,  punit_device_tng),
 148         ICPU(INTEL_FAM6_ATOM_AIRMONT,     punit_device_cht),
 149         {}
 150 };
 151
 152 MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
 153
 154 static int __init punit_atom_debug_init(void)
 155 {
 156         const struct x86_cpu_id *id;
 157         int ret;
 158
 159         id = x86_match_cpu(intel_punit_cpu_ids);
 160         if (!id)
 161                 return -ENODEV;
 162
 163         ret = punit_dbgfs_register((struct punit_device *)id->driver_data);
 164         if (ret < 0)
 165                 return ret;
 166
 167         return 0;
 168 }
 169
 170 static void __exit punit_atom_debug_exit(void)
 171 {
 172         punit_dbgfs_unregister();
 173 }
 174
 175 module_init(punit_atom_debug_init);
 176 module_exit(punit_atom_debug_exit);
 177
 178 MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>");
 179 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
 180 MODULE_DESCRIPTION("Driver for Punit devices states debugging");
 181 MODULE_LICENSE("GPL v2");