1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
4 *
5 * Library for common functions for Intel SpeedStep v.1 and v.2 support
6 *
7 * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
8 */
9
10
11
12 /* processors */
13 enum speedstep_processor {
14 SPEEDSTEP_CPU_PIII_C_EARLY = 0x00000001, /* Coppermine core */
15 SPEEDSTEP_CPU_PIII_C = 0x00000002, /* Coppermine core */
16 SPEEDSTEP_CPU_PIII_T = 0x00000003, /* Tualatin core */
17 SPEEDSTEP_CPU_P4M = 0x00000004, /* P4-M */
18 /* the following processors are not speedstep-capable and are not auto-detected
19 * in speedstep_detect_processor(). However, their speed can be detected using
20 * the speedstep_get_frequency() call. */
21 SPEEDSTEP_CPU_PM = 0xFFFFFF03, /* Pentium M */
22 SPEEDSTEP_CPU_P4D = 0xFFFFFF04, /* desktop P4 */
23 SPEEDSTEP_CPU_PCORE = 0xFFFFFF05, /* Core */
24 };
25
26 /* speedstep states -- only two of them */
27
28 #define SPEEDSTEP_HIGH 0x00000000
29 #define SPEEDSTEP_LOW 0x00000001
30
31
32 /* detect a speedstep-capable processor */
33 extern enum speedstep_processor speedstep_detect_processor(void);
34
35 /* detect the current speed (in khz) of the processor */
36 extern unsigned int speedstep_get_frequency(enum speedstep_processor processor);
37
38
39 /* detect the low and high speeds of the processor. The callback
40 * set_state"'s first argument is either SPEEDSTEP_HIGH or
41 * SPEEDSTEP_LOW; the second argument is zero so that no
42 * cpufreq_notify_transition calls are initiated.
43 */
44 extern unsigned int speedstep_get_freqs(enum speedstep_processor processor,
45 unsigned int *low_speed,
46 unsigned int *high_speed,
47 unsigned int *transition_latency,
48 void (*set_state) (unsigned int state));