xref: /linux/arch/x86/platform/atom/punit_atom_debug.c (revision 36a1818f5a1e50b805317ba13f827067d50f6970)
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(model, data)						 \
169 	X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_##model, \
170 					   X86_FEATURE_MWAIT, data)
171 
172 static const struct x86_cpu_id intel_punit_cpu_ids[] = {
173 	X86_MATCH(ATOM_SILVERMONT,		&punit_device_byt),
174 	X86_MATCH(ATOM_SILVERMONT_MID,		&punit_device_tng),
175 	X86_MATCH(ATOM_AIRMONT,			&punit_device_cht),
176 	{}
177 };
178 MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
179 
180 static int __init punit_atom_debug_init(void)
181 {
182 	struct punit_device *punit_device;
183 	const struct x86_cpu_id *id;
184 
185 	id = x86_match_cpu(intel_punit_cpu_ids);
186 	if (!id)
187 		return -ENODEV;
188 
189 	punit_device = (struct punit_device *)id->driver_data;
190 	punit_dbgfs_register(punit_device);
191 	punit_s2idle_check_register(punit_device);
192 
193 	return 0;
194 }
195 
196 static void __exit punit_atom_debug_exit(void)
197 {
198 	punit_s2idle_check_unregister();
199 	punit_dbgfs_unregister();
200 }
201 
202 module_init(punit_atom_debug_init);
203 module_exit(punit_atom_debug_exit);
204 
205 MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>");
206 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
207 MODULE_DESCRIPTION("Driver for Punit devices states debugging");
208 MODULE_LICENSE("GPL v2");
209