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
43struct punit_device {
44 char *name;
45 int reg;
46 int sss_pos;
47};
48
49static 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
57static 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
67static 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
77static const char * const dstates[] = {"D0", "D0i1", "D0i2", "D0i3"};
78
79static 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(m: seq_file, s: "\n\nPUNIT NORTH COMPLEX DEVICES :\n");
87 while (punit_devp->name) {
88 status = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ,
89 offset: punit_devp->reg, mdr: &punit_pwr_status);
90 if (status) {
91 seq_printf(m: seq_file, fmt: "%9s : Read Failed\n",
92 punit_devp->name);
93 } else {
94 index = (punit_pwr_status >> punit_devp->sss_pos) & 3;
95 seq_printf(m: seq_file, fmt: "%9s : %s\n", punit_devp->name,
96 dstates[index]);
97 }
98 punit_devp++;
99 }
100
101 return 0;
102}
103DEFINE_SHOW_ATTRIBUTE(punit_dev_state);
104
105static struct dentry *punit_dbg_file;
106
107static void punit_dbgfs_register(struct punit_device *punit_device)
108{
109 punit_dbg_file = debugfs_create_dir(name: "punit_atom", NULL);
110
111 debugfs_create_file(name: "dev_power_state", mode: 0444, parent: punit_dbg_file,
112 data: punit_device, fops: &punit_dev_state_fops);
113}
114
115static void punit_dbgfs_unregister(void)
116{
117 debugfs_remove_recursive(dentry: punit_dbg_file);
118}
119
120#define X86_MATCH(model, data) \
121 X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_##model, \
122 X86_FEATURE_MWAIT, data)
123
124static const struct x86_cpu_id intel_punit_cpu_ids[] = {
125 X86_MATCH(ATOM_SILVERMONT, &punit_device_byt),
126 X86_MATCH(ATOM_SILVERMONT_MID, &punit_device_tng),
127 X86_MATCH(ATOM_AIRMONT, &punit_device_cht),
128 {}
129};
130MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
131
132static int __init punit_atom_debug_init(void)
133{
134 const struct x86_cpu_id *id;
135
136 id = x86_match_cpu(match: intel_punit_cpu_ids);
137 if (!id)
138 return -ENODEV;
139
140 punit_dbgfs_register(punit_device: (struct punit_device *)id->driver_data);
141
142 return 0;
143}
144
145static void __exit punit_atom_debug_exit(void)
146{
147 punit_dbgfs_unregister();
148}
149
150module_init(punit_atom_debug_init);
151module_exit(punit_atom_debug_exit);
152
153MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>");
154MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
155MODULE_DESCRIPTION("Driver for Punit devices states debugging");
156MODULE_LICENSE("GPL v2");
157

source code of linux/arch/x86/platform/atom/punit_atom_debug.c