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
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