1 /*
2  *  (c) 2003-2006 Advanced Micro Devices, Inc.
3  *  Your use of this code is subject to the terms and conditions of the
4  *  GNU general public license version 2. See "COPYING" or
5  *  http://www.gnu.org/licenses/gpl.html
6  */
7 
8 enum pstate {
9 	HW_PSTATE_INVALID = 0xff,
10 	HW_PSTATE_0 = 0,
11 	HW_PSTATE_1 = 1,
12 	HW_PSTATE_2 = 2,
13 	HW_PSTATE_3 = 3,
14 	HW_PSTATE_4 = 4,
15 	HW_PSTATE_5 = 5,
16 	HW_PSTATE_6 = 6,
17 	HW_PSTATE_7 = 7,
18 };
19 
20 struct powernow_k8_data {
21 	unsigned int cpu;
22 
23 	u32 numps;  /* number of p-states */
24 	u32 batps;  /* number of p-states supported on battery */
25 	u32 max_hw_pstate; /* maximum legal hardware pstate */
26 
27 	/* these values are constant when the PSB is used to determine
28 	 * vid/fid pairings, but are modified during the ->target() call
29 	 * when ACPI is used */
30 	u32 rvo;     /* ramp voltage offset */
31 	u32 irt;     /* isochronous relief time */
32 	u32 vidmvs;  /* usable value calculated from mvs */
33 	u32 vstable; /* voltage stabilization time, units 20 us */
34 	u32 plllock; /* pll lock time, units 1 us */
35         u32 exttype; /* extended interface = 1 */
36 
37 	/* keep track of the current fid / vid or pstate */
38 	u32 currvid;
39 	u32 currfid;
40 	enum pstate currpstate;
41 
42 	/* the powernow_table includes all frequency and vid/fid pairings:
43 	 * fid are the lower 8 bits of the index, vid are the upper 8 bits.
44 	 * frequency is in kHz */
45 	struct cpufreq_frequency_table  *powernow_table;
46 
47 	/* the acpi table needs to be kept. it's only available if ACPI was
48 	 * used to determine valid frequency/vid/fid states */
49 	struct acpi_processor_performance acpi_data;
50 
51 	/* we need to keep track of associated cores, but let cpufreq
52 	 * handle hotplug events - so just point at cpufreq pol->cpus
53 	 * structure */
54 	struct cpumask *available_cores;
55 };
56 
57 /* processor's cpuid instruction support */
58 #define CPUID_PROCESSOR_SIGNATURE	1	/* function 1 */
59 #define CPUID_XFAM			0x0ff00000	/* extended family */
60 #define CPUID_XFAM_K8			0
61 #define CPUID_XMOD			0x000f0000	/* extended model */
62 #define CPUID_XMOD_REV_MASK		0x000c0000
63 #define CPUID_XFAM_10H			0x00100000	/* family 0x10 */
64 #define CPUID_USE_XFAM_XMOD		0x00000f00
65 #define CPUID_GET_MAX_CAPABILITIES	0x80000000
66 #define CPUID_FREQ_VOLT_CAPABILITIES	0x80000007
67 #define P_STATE_TRANSITION_CAPABLE	6
68 
69 /* Model Specific Registers for p-state transitions. MSRs are 64-bit. For     */
70 /* writes (wrmsr - opcode 0f 30), the register number is placed in ecx, and   */
71 /* the value to write is placed in edx:eax. For reads (rdmsr - opcode 0f 32), */
72 /* the register number is placed in ecx, and the data is returned in edx:eax. */
73 
74 #define MSR_FIDVID_CTL      0xc0010041
75 #define MSR_FIDVID_STATUS   0xc0010042
76 
77 /* Field definitions within the FID VID Low Control MSR : */
78 #define MSR_C_LO_INIT_FID_VID     0x00010000
79 #define MSR_C_LO_NEW_VID          0x00003f00
80 #define MSR_C_LO_NEW_FID          0x0000003f
81 #define MSR_C_LO_VID_SHIFT        8
82 
83 /* Field definitions within the FID VID High Control MSR : */
84 #define MSR_C_HI_STP_GNT_TO	  0x000fffff
85 
86 /* Field definitions within the FID VID Low Status MSR : */
87 #define MSR_S_LO_CHANGE_PENDING   0x80000000   /* cleared when completed */
88 #define MSR_S_LO_MAX_RAMP_VID     0x3f000000
89 #define MSR_S_LO_MAX_FID          0x003f0000
90 #define MSR_S_LO_START_FID        0x00003f00
91 #define MSR_S_LO_CURRENT_FID      0x0000003f
92 
93 /* Field definitions within the FID VID High Status MSR : */
94 #define MSR_S_HI_MIN_WORKING_VID  0x3f000000
95 #define MSR_S_HI_MAX_WORKING_VID  0x003f0000
96 #define MSR_S_HI_START_VID        0x00003f00
97 #define MSR_S_HI_CURRENT_VID      0x0000003f
98 #define MSR_C_HI_STP_GNT_BENIGN	  0x00000001
99 
100 
101 /* Hardware Pstate _PSS and MSR definitions */
102 #define USE_HW_PSTATE		0x00000080
103 #define HW_PSTATE_MASK 		0x00000007
104 #define HW_PSTATE_VALID_MASK 	0x80000000
105 #define HW_PSTATE_MAX_MASK	0x000000f0
106 #define HW_PSTATE_MAX_SHIFT	4
107 #define MSR_PSTATE_DEF_BASE 	0xc0010064 /* base of Pstate MSRs */
108 #define MSR_PSTATE_STATUS 	0xc0010063 /* Pstate Status MSR */
109 #define MSR_PSTATE_CTRL 	0xc0010062 /* Pstate control MSR */
110 #define MSR_PSTATE_CUR_LIMIT	0xc0010061 /* pstate current limit MSR */
111 
112 /* define the two driver architectures */
113 #define CPU_OPTERON 0
114 #define CPU_HW_PSTATE 1
115 
116 
117 /*
118  * There are restrictions frequencies have to follow:
119  * - only 1 entry in the low fid table ( <=1.4GHz )
120  * - lowest entry in the high fid table must be >= 2 * the entry in the
121  *   low fid table
122  * - lowest entry in the high fid table must be a <= 200MHz + 2 * the entry
123  *   in the low fid table
124  * - the parts can only step at <= 200 MHz intervals, odd fid values are
125  *   supported in revision G and later revisions.
126  * - lowest frequency must be >= interprocessor hypertransport link speed
127  *   (only applies to MP systems obviously)
128  */
129 
130 /* fids (frequency identifiers) are arranged in 2 tables - lo and hi */
131 #define LO_FID_TABLE_TOP     7	/* fid values marking the boundary    */
132 #define HI_FID_TABLE_BOTTOM  8	/* between the low and high tables    */
133 
134 #define LO_VCOFREQ_TABLE_TOP    1400	/* corresponding vco frequency values */
135 #define HI_VCOFREQ_TABLE_BOTTOM 1600
136 
137 #define MIN_FREQ_RESOLUTION  200 /* fids jump by 2 matching freq jumps by 200 */
138 
139 #define MAX_FID 0x2a	/* Spec only gives FID values as far as 5 GHz */
140 #define LEAST_VID 0x3e	/* Lowest (numerically highest) useful vid value */
141 
142 #define MIN_FREQ 800	/* Min and max freqs, per spec */
143 #define MAX_FREQ 5000
144 
145 #define INVALID_FID_MASK 0xffffffc0  /* not a valid fid if these bits are set */
146 #define INVALID_VID_MASK 0xffffffc0  /* not a valid vid if these bits are set */
147 
148 #define VID_OFF 0x3f
149 
150 #define STOP_GRANT_5NS 1 /* min poss memory access latency for voltage change */
151 
152 #define PLL_LOCK_CONVERSION (1000/5) /* ms to ns, then divide by clock period */
153 
154 #define MAXIMUM_VID_STEPS 1  /* Current cpus only allow a single step of 25mV */
155 #define VST_UNITS_20US 20   /* Voltage Stabilization Time is in units of 20us */
156 
157 /*
158  * Most values of interest are encoded in a single field of the _PSS
159  * entries: the "control" value.
160  */
161 
162 #define IRT_SHIFT      30
163 #define RVO_SHIFT      28
164 #define EXT_TYPE_SHIFT 27
165 #define PLL_L_SHIFT    20
166 #define MVS_SHIFT      18
167 #define VST_SHIFT      11
168 #define VID_SHIFT       6
169 #define IRT_MASK        3
170 #define RVO_MASK        3
171 #define EXT_TYPE_MASK   1
172 #define PLL_L_MASK   0x7f
173 #define MVS_MASK        3
174 #define VST_MASK     0x7f
175 #define VID_MASK     0x1f
176 #define FID_MASK     0x1f
177 #define EXT_VID_MASK 0x3f
178 #define EXT_FID_MASK 0x3f
179 
180 
181 /*
182  * Version 1.4 of the PSB table. This table is constructed by BIOS and is
183  * to tell the OS's power management driver which VIDs and FIDs are
184  * supported by this particular processor.
185  * If the data in the PSB / PST is wrong, then this driver will program the
186  * wrong values into hardware, which is very likely to lead to a crash.
187  */
188 
189 #define PSB_ID_STRING      "AMDK7PNOW!"
190 #define PSB_ID_STRING_LEN  10
191 
192 #define PSB_VERSION_1_4  0x14
193 
194 struct psb_s {
195 	u8 signature[10];
196 	u8 tableversion;
197 	u8 flags1;
198 	u16 vstable;
199 	u8 flags2;
200 	u8 num_tables;
201 	u32 cpuid;
202 	u8 plllocktime;
203 	u8 maxfid;
204 	u8 maxvid;
205 	u8 numps;
206 };
207 
208 /* Pairs of fid/vid values are appended to the version 1.4 PSB table. */
209 struct pst_s {
210 	u8 fid;
211 	u8 vid;
212 };
213 
214 static int core_voltage_pre_transition(struct powernow_k8_data *data,
215 	u32 reqvid, u32 regfid);
216 static int core_voltage_post_transition(struct powernow_k8_data *data, u32 reqvid);
217 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid);
218 
219 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index);
220 
221 static int fill_powernow_table_pstate(struct powernow_k8_data *data, struct cpufreq_frequency_table *powernow_table);
222 static int fill_powernow_table_fidvid(struct powernow_k8_data *data, struct cpufreq_frequency_table *powernow_table);
223