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 #define pr_fmt(fmt) "punit_atom: " fmt 11 12 #include <linux/acpi.h> 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/device.h> 16 #include <linux/debugfs.h> 17 #include <linux/seq_file.h> 18 #include <linux/io.h> 19 #include <asm/cpu_device_id.h> 20 #include <asm/intel-family.h> 21 #include <asm/iosf_mbi.h> 22 23 /* Subsystem config/status Video processor */ 24 #define VED_SS_PM0 0x32 25 /* Subsystem config/status ISP (Image Signal Processor) */ 26 #define ISP_SS_PM0 0x39 27 /* Subsystem config/status Input/output controller */ 28 #define MIO_SS_PM 0x3B 29 /* Shift bits for getting status for video, isp and i/o */ 30 #define SSS_SHIFT 24 31 32 /* Power gate status reg */ 33 #define PWRGT_STATUS 0x61 34 /* Shift bits for getting status for graphics rendering */ 35 #define RENDER_POS 0 36 /* Shift bits for getting status for media control */ 37 #define MEDIA_POS 2 38 /* Shift bits for getting status for Valley View/Baytrail display */ 39 #define VLV_DISPLAY_POS 6 40 41 /* Subsystem config/status display for Cherry Trail SOC */ 42 #define CHT_DSP_SSS 0x36 43 /* Shift bits for getting status for display */ 44 #define CHT_DSP_SSS_POS 16 45 46 struct punit_device { 47 char *name; 48 int reg; 49 int sss_pos; 50 }; 51 52 static const struct punit_device punit_device_tng[] = { 53 { "DISPLAY", CHT_DSP_SSS, SSS_SHIFT }, 54 { "VED", VED_SS_PM0, SSS_SHIFT }, 55 { "ISP", ISP_SS_PM0, SSS_SHIFT }, 56 { "MIO", MIO_SS_PM, SSS_SHIFT }, 57 { NULL } 58 }; 59 60 static const struct punit_device punit_device_byt[] = { 61 { "GFX RENDER", PWRGT_STATUS, RENDER_POS }, 62 { "GFX MEDIA", PWRGT_STATUS, MEDIA_POS }, 63 { "DISPLAY", PWRGT_STATUS, VLV_DISPLAY_POS }, 64 { "VED", VED_SS_PM0, SSS_SHIFT }, 65 { "ISP", ISP_SS_PM0, SSS_SHIFT }, 66 { "MIO", MIO_SS_PM, SSS_SHIFT }, 67 { NULL } 68 }; 69 70 static const struct punit_device punit_device_cht[] = { 71 { "GFX RENDER", PWRGT_STATUS, RENDER_POS }, 72 { "GFX MEDIA", PWRGT_STATUS, MEDIA_POS }, 73 { "DISPLAY", CHT_DSP_SSS, CHT_DSP_SSS_POS }, 74 { "VED", VED_SS_PM0, SSS_SHIFT }, 75 { "ISP", ISP_SS_PM0, SSS_SHIFT }, 76 { "MIO", MIO_SS_PM, SSS_SHIFT }, 77 { NULL } 78 }; 79 80 static const char * const dstates[] = {"D0", "D0i1", "D0i2", "D0i3"}; 81 82 static int punit_dev_state_show(struct seq_file *seq_file, void *unused) 83 { 84 u32 punit_pwr_status; 85 struct punit_device *punit_devp = seq_file->private; 86 int index; 87 int status; 88 89 seq_puts(seq_file, "\n\nPUNIT NORTH COMPLEX DEVICES :\n"); 90 while (punit_devp->name) { 91 status = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, 92 punit_devp->reg, &punit_pwr_status); 93 if (status) { 94 seq_printf(seq_file, "%9s : Read Failed\n", 95 punit_devp->name); 96 } else { 97 index = (punit_pwr_status >> punit_devp->sss_pos) & 3; 98 seq_printf(seq_file, "%9s : %s\n", punit_devp->name, 99 dstates[index]); 100 } 101 punit_devp++; 102 } 103 104 return 0; 105 } 106 DEFINE_SHOW_ATTRIBUTE(punit_dev_state); 107 108 static struct dentry *punit_dbg_file; 109 110 static void punit_dbgfs_register(struct punit_device *punit_device) 111 { 112 punit_dbg_file = debugfs_create_dir("punit_atom", NULL); 113 114 debugfs_create_file("dev_power_state", 0444, punit_dbg_file, 115 punit_device, &punit_dev_state_fops); 116 } 117 118 static void punit_dbgfs_unregister(void) 119 { 120 debugfs_remove_recursive(punit_dbg_file); 121 } 122 123 #if defined(CONFIG_ACPI) && defined(CONFIG_SUSPEND) 124 static const struct punit_device *punit_dev; 125 126 static void punit_s2idle_check(void) 127 { 128 const struct punit_device *punit_devp; 129 u32 punit_pwr_status, dstate; 130 int status; 131 132 for (punit_devp = punit_dev; punit_devp->name; punit_devp++) { 133 /* Skip MIO, it is on till the very last moment */ 134 if (punit_devp->reg == MIO_SS_PM) 135 continue; 136 137 status = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, 138 punit_devp->reg, &punit_pwr_status); 139 if (status) { 140 pr_err("%s read failed\n", punit_devp->name); 141 } else { 142 dstate = (punit_pwr_status >> punit_devp->sss_pos) & 3; 143 if (!dstate) 144 pr_err("%s is in D0 prior to s2idle\n", punit_devp->name); 145 } 146 } 147 } 148 149 static struct acpi_s2idle_dev_ops punit_s2idle_ops = { 150 .check = punit_s2idle_check, 151 }; 152 153 static void punit_s2idle_check_register(struct punit_device *punit_device) 154 { 155 punit_dev = punit_device; 156 acpi_register_lps0_dev(&punit_s2idle_ops); 157 } 158 159 static void punit_s2idle_check_unregister(void) 160 { 161 acpi_unregister_lps0_dev(&punit_s2idle_ops); 162 } 163 #else 164 static void punit_s2idle_check_register(struct punit_device *punit_device) {} 165 static void punit_s2idle_check_unregister(void) {} 166 #endif 167 168 #define X86_MATCH(vfm, data) \ 169 X86_MATCH_VFM_FEATURE(vfm, X86_FEATURE_MWAIT, data) 170 171 static const struct x86_cpu_id intel_punit_cpu_ids[] = { 172 X86_MATCH(INTEL_ATOM_SILVERMONT, &punit_device_byt), 173 X86_MATCH(INTEL_ATOM_SILVERMONT_MID, &punit_device_tng), 174 X86_MATCH(INTEL_ATOM_AIRMONT, &punit_device_cht), 175 {} 176 }; 177 MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids); 178 179 static int __init punit_atom_debug_init(void) 180 { 181 struct punit_device *punit_device; 182 const struct x86_cpu_id *id; 183 184 id = x86_match_cpu(intel_punit_cpu_ids); 185 if (!id) 186 return -ENODEV; 187 188 punit_device = (struct punit_device *)id->driver_data; 189 punit_dbgfs_register(punit_device); 190 punit_s2idle_check_register(punit_device); 191 192 return 0; 193 } 194 195 static void __exit punit_atom_debug_exit(void) 196 { 197 punit_s2idle_check_unregister(); 198 punit_dbgfs_unregister(); 199 } 200 201 module_init(punit_atom_debug_init); 202 module_exit(punit_atom_debug_exit); 203 204 MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>"); 205 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>"); 206 MODULE_DESCRIPTION("Driver for Punit devices states debugging"); 207 MODULE_LICENSE("GPL v2"); 208