1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright © 2023 Intel Corporation
4 */
5
6 #include <linux/moduleparam.h>
7 #include <linux/slab.h>
8 #include <linux/string_choices.h>
9
10 #include <drm/drm_print.h>
11
12 #include "intel_display_params.h"
13
14 #define intel_display_param_named(name, T, perm, desc) \
15 module_param_named(name, intel_display_modparams.name, T, perm); \
16 MODULE_PARM_DESC(name, desc)
17 #define intel_display_param_named_unsafe(name, T, perm, desc) \
18 module_param_named_unsafe(name, intel_display_modparams.name, T, perm); \
19 MODULE_PARM_DESC(name, desc)
20
21 static struct intel_display_params intel_display_modparams __read_mostly = {
22 #define MEMBER(T, member, value, ...) .member = (value),
23 INTEL_DISPLAY_PARAMS_FOR_EACH(MEMBER)
24 #undef MEMBER
25 };
26 /*
27 * Note: As a rule, keep module parameter sysfs permissions read-only
28 * 0400. Runtime changes are only supported through i915 debugfs.
29 *
30 * For any exceptions requiring write access and runtime changes through module
31 * parameter sysfs, prevent debugfs file creation by setting the parameter's
32 * debugfs mode to 0.
33 */
34
35 intel_display_param_named_unsafe(dmc_firmware_path, charp, 0400,
36 "DMC firmware path to use instead of the default one. "
37 "Use /dev/null to disable DMC and runtime PM.");
38
39 intel_display_param_named_unsafe(vbt_firmware, charp, 0400,
40 "Load VBT from specified file under /lib/firmware");
41
42 intel_display_param_named_unsafe(lvds_channel_mode, int, 0400,
43 "Specify LVDS channel mode "
44 "(0=probe BIOS [default], 1=single-channel, 2=dual-channel)");
45
46 intel_display_param_named_unsafe(panel_use_ssc, int, 0400,
47 "Use Spread Spectrum Clock with panels [LVDS/eDP] "
48 "(default: auto from VBT)");
49
50 intel_display_param_named_unsafe(vbt_sdvo_panel_type, int, 0400,
51 "Override/Ignore selection of SDVO panel mode in the VBT "
52 "(-2=ignore, -1=auto [default], index in VBT BIOS table)");
53
54 intel_display_param_named_unsafe(enable_dc, int, 0400,
55 "Enable power-saving display C-states. "
56 "(-1=auto [default]; 0=disable; 1=up to DC5; 2=up to DC6; "
57 "3=up to DC5 with DC3CO; 4=up to DC6 with DC3CO)");
58
59 intel_display_param_named_unsafe(enable_dpt, bool, 0400,
60 "Enable display page table (DPT) (default: true)");
61
62 intel_display_param_named_unsafe(enable_dsb, bool, 0400,
63 "Enable display state buffer (DSB) (default: true)");
64
65 intel_display_param_named_unsafe(enable_sagv, bool, 0400,
66 "Enable system agent voltage/frequency scaling (SAGV) (default: true)");
67
68 intel_display_param_named_unsafe(disable_power_well, int, 0400,
69 "Disable display power wells when possible "
70 "(-1=auto [default], 0=power wells always on, 1=power wells disabled when possible)");
71
72 intel_display_param_named_unsafe(enable_ips, bool, 0400, "Enable IPS (default: true)");
73
74 intel_display_param_named_unsafe(invert_brightness, int, 0400,
75 "Invert backlight brightness "
76 "(-1 force normal, 0 machine defaults, 1 force inversion), please "
77 "report PCI device ID, subsystem vendor and subsystem device ID "
78 "to dri-devel@lists.freedesktop.org, if your machine needs it. "
79 "It will then be included in an upcoming module version.");
80
81 /* WA to get away with the default setting in VBT for early platforms.Will be removed */
82 intel_display_param_named_unsafe(edp_vswing, int, 0400,
83 "Ignore/Override vswing pre-emph table selection from VBT "
84 "(0=use value from vbt [default], 1=low power swing(200mV),"
85 "2=default swing(400mV))");
86
87 intel_display_param_named(enable_dpcd_backlight, int, 0400,
88 "Enable support for DPCD backlight control"
89 "(-1=use per-VBT LFP backlight type setting [default], 0=disabled, 1=enable, 2=force VESA interface, 3=force Intel interface)");
90
91 intel_display_param_named_unsafe(load_detect_test, bool, 0400,
92 "Force-enable the VGA load detect code for testing (default:false). "
93 "For developers only.");
94
95 intel_display_param_named_unsafe(force_reset_modeset_test, bool, 0400,
96 "Force a modeset during gpu reset for testing (default:false). "
97 "For developers only.");
98
99 intel_display_param_named(disable_display, bool, 0400,
100 "Disable display (default: false)");
101
102 intel_display_param_named(verbose_state_checks, bool, 0400,
103 "Enable verbose logs (ie. WARN_ON()) in case of unexpected hw state conditions.");
104
105 intel_display_param_named_unsafe(nuclear_pageflip, bool, 0400,
106 "Force enable atomic functionality on platforms that don't have full support yet.");
107
108 intel_display_param_named_unsafe(enable_dp_mst, bool, 0400,
109 "Enable multi-stream transport (MST) for new DisplayPort sinks. (default: true)");
110
111 intel_display_param_named_unsafe(enable_fbc, int, 0400,
112 "Enable frame buffer compression for power savings "
113 "(default: -1 (use per-chip default))");
114
115 intel_display_param_named_unsafe(enable_psr, int, 0400,
116 "Enable PSR "
117 "(0=disabled, 1=enable up to PSR1, 2=enable up to PSR2) "
118 "Default: -1 (use per-chip default)");
119
120 intel_display_param_named(psr_safest_params, bool, 0400,
121 "Replace PSR VBT parameters by the safest and not optimal ones. This "
122 "is helpful to detect if PSR issues are related to bad values set in "
123 " VBT. (0=use VBT parameters, 1=use safest parameters)"
124 "Default: 0");
125
126 intel_display_param_named_unsafe(enable_psr2_sel_fetch, bool, 0400,
127 "Enable PSR2 and Panel Replay selective fetch "
128 "(0=disabled, 1=enabled) "
129 "Default: 1");
130
131 intel_display_param_named_unsafe(enable_dmc_wl, int, 0400,
132 "Enable DMC wakelock "
133 "(-1=use per-chip default, 0=disabled, 1=enabled) "
134 "Default: -1");
135
136 __maybe_unused
_param_print_bool(struct drm_printer * p,const char * driver_name,const char * name,bool val)137 static void _param_print_bool(struct drm_printer *p, const char *driver_name,
138 const char *name, bool val)
139 {
140 drm_printf(p, "%s.%s=%s\n", driver_name, name, str_yes_no(val));
141 }
142
143 __maybe_unused
_param_print_int(struct drm_printer * p,const char * driver_name,const char * name,int val)144 static void _param_print_int(struct drm_printer *p, const char *driver_name,
145 const char *name, int val)
146 {
147 drm_printf(p, "%s.%s=%d\n", driver_name, name, val);
148 }
149
150 __maybe_unused
_param_print_uint(struct drm_printer * p,const char * driver_name,const char * name,unsigned int val)151 static void _param_print_uint(struct drm_printer *p, const char *driver_name,
152 const char *name, unsigned int val)
153 {
154 drm_printf(p, "%s.%s=%u\n", driver_name, name, val);
155 }
156
157 __maybe_unused
_param_print_ulong(struct drm_printer * p,const char * driver_name,const char * name,unsigned long val)158 static void _param_print_ulong(struct drm_printer *p, const char *driver_name,
159 const char *name, unsigned long val)
160 {
161 drm_printf(p, "%s.%s=%lu\n", driver_name, name, val);
162 }
163
164 __maybe_unused
_param_print_charp(struct drm_printer * p,const char * driver_name,const char * name,const char * val)165 static void _param_print_charp(struct drm_printer *p, const char *driver_name,
166 const char *name, const char *val)
167 {
168 drm_printf(p, "%s.%s=%s\n", driver_name, name, val);
169 }
170
171 #define _param_print(p, driver_name, name, val) \
172 _Generic(val, \
173 bool : _param_print_bool, \
174 int : _param_print_int, \
175 unsigned int : _param_print_uint, \
176 unsigned long : _param_print_ulong, \
177 char * : _param_print_charp)(p, driver_name, name, val)
178
179 /**
180 * intel_display_params_dump - dump intel display modparams
181 * @params: display params
182 * @driver_name: driver name to use for printing
183 * @p: the &drm_printer
184 *
185 * Pretty printer for i915 modparams.
186 */
intel_display_params_dump(const struct intel_display_params * params,const char * driver_name,struct drm_printer * p)187 void intel_display_params_dump(const struct intel_display_params *params,
188 const char *driver_name, struct drm_printer *p)
189 {
190 #define PRINT(T, x, ...) _param_print(p, driver_name, #x, params->x);
191 INTEL_DISPLAY_PARAMS_FOR_EACH(PRINT);
192 #undef PRINT
193 }
194
_param_dup_charp(char ** valp)195 __maybe_unused static void _param_dup_charp(char **valp)
196 {
197 *valp = kstrdup(*valp ? *valp : "", GFP_ATOMIC);
198 }
199
_param_nop(void * valp)200 __maybe_unused static void _param_nop(void *valp)
201 {
202 }
203
204 #define _param_dup(valp) \
205 _Generic(valp, \
206 char ** : _param_dup_charp, \
207 default : _param_nop) \
208 (valp)
209
intel_display_params_copy(struct intel_display_params * dest)210 void intel_display_params_copy(struct intel_display_params *dest)
211 {
212 *dest = intel_display_modparams;
213 #define DUP(T, x, ...) _param_dup(&dest->x);
214 INTEL_DISPLAY_PARAMS_FOR_EACH(DUP);
215 #undef DUP
216 }
217
_param_free_charp(char ** valp)218 __maybe_unused static void _param_free_charp(char **valp)
219 {
220 kfree(*valp);
221 *valp = NULL;
222 }
223
224 #define _param_free(valp) \
225 _Generic(valp, \
226 char ** : _param_free_charp, \
227 default : _param_nop) \
228 (valp)
229
230 /* free the allocated members, *not* the passed in params itself */
intel_display_params_free(struct intel_display_params * params)231 void intel_display_params_free(struct intel_display_params *params)
232 {
233 #define FREE(T, x, ...) _param_free(¶ms->x);
234 INTEL_DISPLAY_PARAMS_FOR_EACH(FREE);
235 #undef FREE
236 }
237