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));
49