root/arch/x86/platform/atom/punit_atom_debug.c

DEFINITIONS

1. punit_dev_state_show
2. punit_dbgfs_register
3. punit_dbgfs_unregister
4. punit_atom_debug_init
5. punit_atom_debug_exit

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Intel SOC Punit device state debug driver
   4  * Punit controls power management for North Complex devices (Graphics
   5  * blocks, Image Signal Processing, video processing, display, DSP etc.)
   6  *
   7  * Copyright (c) 2015, Intel Corporation.
   8  */
   9 
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/device.h>
  13 #include <linux/debugfs.h>
  14 #include <linux/seq_file.h>
  15 #include <linux/io.h>
  16 #include <asm/cpu_device_id.h>
  17 #include <asm/intel-family.h>
  18 #include <asm/iosf_mbi.h>
  19 
  20 /* Subsystem config/status Video processor */
  21 #define VED_SS_PM0              0x32
  22 /* Subsystem config/status ISP (Image Signal Processor) */
  23 #define ISP_SS_PM0              0x39
  24 /* Subsystem config/status Input/output controller */
  25 #define MIO_SS_PM               0x3B
  26 /* Shift bits for getting status for video, isp and i/o */
  27 #define SSS_SHIFT               24
  28 
  29 /* Power gate status reg */
  30 #define PWRGT_STATUS            0x61
  31 /* Shift bits for getting status for graphics rendering */
  32 #define RENDER_POS              0
  33 /* Shift bits for getting status for media control */
  34 #define MEDIA_POS               2
  35 /* Shift bits for getting status for Valley View/Baytrail display */
  36 #define VLV_DISPLAY_POS         6
  37 
  38 /* Subsystem config/status display for Cherry Trail SOC */
  39 #define CHT_DSP_SSS             0x36
  40 /* Shift bits for getting status for display */
  41 #define CHT_DSP_SSS_POS         16
  42 
  43 struct punit_device {
  44         char *name;
  45         int reg;
  46         int sss_pos;
  47 };
  48 
  49 static const struct punit_device punit_device_tng[] = {
  50         { "DISPLAY",    CHT_DSP_SSS,    SSS_SHIFT },
  51         { "VED",        VED_SS_PM0,     SSS_SHIFT },
  52         { "ISP",        ISP_SS_PM0,     SSS_SHIFT },
  53         { "MIO",        MIO_SS_PM,      SSS_SHIFT },
  54         { NULL }
  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(BT_MBI_UNIT_PMC, MBI_REG_READ,
  89                                        punit_devp->reg, &punit_pwr_status);
  90                 if (status) {
  91                         seq_printf(seq_file, "%9s : Read Failed\n",
  92                                    punit_devp->name);
  93                 } else  {
  94                         index = (punit_pwr_status >> punit_devp->sss_pos) & 3;
  95                         seq_printf(seq_file, "%9s : %s\n", punit_devp->name,
  96                                    dstates[index]);
  97                 }
  98                 punit_devp++;
  99         }
 100 
 101         return 0;
 102 }
 103 DEFINE_SHOW_ATTRIBUTE(punit_dev_state);
 104 
 105 static struct dentry *punit_dbg_file;
 106 
 107 static void punit_dbgfs_register(struct punit_device *punit_device)
 108 {
 109         punit_dbg_file = debugfs_create_dir("punit_atom", NULL);
 110 
 111         debugfs_create_file("dev_power_state", 0444, punit_dbg_file,
 112                             punit_device, &punit_dev_state_fops);
 113 }
 114 
 115 static void punit_dbgfs_unregister(void)
 116 {
 117         debugfs_remove_recursive(punit_dbg_file);
 118 }
 119 
 120 #define ICPU(model, drv_data) \
 121         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT,\
 122           (kernel_ulong_t)&drv_data }
 123 
 124 static const struct x86_cpu_id intel_punit_cpu_ids[] = {
 125         ICPU(INTEL_FAM6_ATOM_SILVERMONT, punit_device_byt),
 126         ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID,  punit_device_tng),
 127         ICPU(INTEL_FAM6_ATOM_AIRMONT,     punit_device_cht),
 128         {}
 129 };
 130 
 131 MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
 132 
 133 static int __init punit_atom_debug_init(void)
 134 {
 135         const struct x86_cpu_id *id;
 136 
 137         id = x86_match_cpu(intel_punit_cpu_ids);
 138         if (!id)
 139                 return -ENODEV;
 140 
 141         punit_dbgfs_register((struct punit_device *)id->driver_data);
 142 
 143         return 0;
 144 }
 145 
 146 static void __exit punit_atom_debug_exit(void)
 147 {
 148         punit_dbgfs_unregister();
 149 }
 150 
 151 module_init(punit_atom_debug_init);
 152 module_exit(punit_atom_debug_exit);
 153 
 154 MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>");
 155 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
 156 MODULE_DESCRIPTION("Driver for Punit devices states debugging");
 157 MODULE_LICENSE("GPL v2");