1/*
2 * Intel SOC Punit device state debug driver
3 * Punit controls power management for North Complex devices (Graphics
4 * blocks, Image Signal Processing, video processing, display, DSP etc.)
5 *
6 * Copyright (c) 2015, Intel Corporation.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 */
18
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/device.h>
22#include <linux/debugfs.h>
23#include <linux/seq_file.h>
24#include <linux/io.h>
25#include <asm/cpu_device_id.h>
26#include <asm/intel-family.h>
27#include <asm/iosf_mbi.h>
28
29/* Subsystem config/status Video processor */
30#define VED_SS_PM0 0x32
31/* Subsystem config/status ISP (Image Signal Processor) */
32#define ISP_SS_PM0 0x39
33/* Subsystem config/status Input/output controller */
34#define MIO_SS_PM 0x3B
35/* Shift bits for getting status for video, isp and i/o */
36#define SSS_SHIFT 24
37
38/* Power gate status reg */
39#define PWRGT_STATUS 0x61
40/* Shift bits for getting status for graphics rendering */
41#define RENDER_POS 0
42/* Shift bits for getting status for media control */
43#define MEDIA_POS 2
44/* Shift bits for getting status for Valley View/Baytrail display */
45#define VLV_DISPLAY_POS 6
46
47/* Subsystem config/status display for Cherry Trail SOC */
48#define CHT_DSP_SSS 0x36
49/* Shift bits for getting status for display */
50#define CHT_DSP_SSS_POS 16
51
52struct punit_device {
53 char *name;
54 int reg;
55 int sss_pos;
56};
57
58static const struct punit_device punit_device_tng[] = {
59 { "DISPLAY", CHT_DSP_SSS, SSS_SHIFT },
60 { "VED", VED_SS_PM0, SSS_SHIFT },
61 { "ISP", ISP_SS_PM0, SSS_SHIFT },
62 { "MIO", MIO_SS_PM, SSS_SHIFT },
63 { NULL }
64};
65
66static const struct punit_device punit_device_byt[] = {
67 { "GFX RENDER", PWRGT_STATUS, RENDER_POS },
68 { "GFX MEDIA", PWRGT_STATUS, MEDIA_POS },
69 { "DISPLAY", PWRGT_STATUS, VLV_DISPLAY_POS },
70 { "VED", VED_SS_PM0, SSS_SHIFT },
71 { "ISP", ISP_SS_PM0, SSS_SHIFT },
72 { "MIO", MIO_SS_PM, SSS_SHIFT },
73 { NULL }
74};
75
76static const struct punit_device punit_device_cht[] = {
77 { "GFX RENDER", PWRGT_STATUS, RENDER_POS },
78 { "GFX MEDIA", PWRGT_STATUS, MEDIA_POS },
79 { "DISPLAY", CHT_DSP_SSS, CHT_DSP_SSS_POS },
80 { "VED", VED_SS_PM0, SSS_SHIFT },
81 { "ISP", ISP_SS_PM0, SSS_SHIFT },
82 { "MIO", MIO_SS_PM, SSS_SHIFT },
83 { NULL }
84};
85
86static const char * const dstates[] = {"D0", "D0i1", "D0i2", "D0i3"};
87
88static int punit_dev_state_show(struct seq_file *seq_file, void *unused)
89{
90 u32 punit_pwr_status;
91 struct punit_device *punit_devp = seq_file->private;
92 int index;
93 int status;
94
95 seq_puts(seq_file, "\n\nPUNIT NORTH COMPLEX DEVICES :\n");
96 while (punit_devp->name) {
97 status = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ,
98 punit_devp->reg, &punit_pwr_status);
99 if (status) {
100 seq_printf(seq_file, "%9s : Read Failed\n",
101 punit_devp->name);
102 } else {
103 index = (punit_pwr_status >> punit_devp->sss_pos) & 3;
104 seq_printf(seq_file, "%9s : %s\n", punit_devp->name,
105 dstates[index]);
106 }
107 punit_devp++;
108 }
109
110 return 0;
111}
112DEFINE_SHOW_ATTRIBUTE(punit_dev_state);
113
114static struct dentry *punit_dbg_file;
115
116static int punit_dbgfs_register(struct punit_device *punit_device)
117{
118 struct dentry *dev_state;
119
120 punit_dbg_file = debugfs_create_dir("punit_atom", NULL);
121 if (!punit_dbg_file)
122 return -ENXIO;
123
124 dev_state = debugfs_create_file("dev_power_state", 0444,
125 punit_dbg_file, punit_device,
126 &punit_dev_state_fops);
127 if (!dev_state) {
128 pr_err("punit_dev_state register failed\n");
129 debugfs_remove(punit_dbg_file);
130 return -ENXIO;
131 }
132
133 return 0;
134}
135
136static void punit_dbgfs_unregister(void)
137{
138 debugfs_remove_recursive(punit_dbg_file);
139}
140
141#define ICPU(model, drv_data) \
142 { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT,\
143 (kernel_ulong_t)&drv_data }
144
145static const struct x86_cpu_id intel_punit_cpu_ids[] = {
146 ICPU(INTEL_FAM6_ATOM_SILVERMONT, punit_device_byt),
147 ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID, punit_device_tng),
148 ICPU(INTEL_FAM6_ATOM_AIRMONT, punit_device_cht),
149 {}
150};
151
152MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
153
154static int __init punit_atom_debug_init(void)
155{
156 const struct x86_cpu_id *id;
157 int ret;
158
159 id = x86_match_cpu(intel_punit_cpu_ids);
160 if (!id)
161 return -ENODEV;
162
163 ret = punit_dbgfs_register((struct punit_device *)id->driver_data);
164 if (ret < 0)
165 return ret;
166
167 return 0;
168}
169
170static void __exit punit_atom_debug_exit(void)
171{
172 punit_dbgfs_unregister();
173}
174
175module_init(punit_atom_debug_init);
176module_exit(punit_atom_debug_exit);
177
178MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>");
179MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
180MODULE_DESCRIPTION("Driver for Punit devices states debugging");
181MODULE_LICENSE("GPL v2");
182