1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2008 Marvell International Ltd.
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/sched.h>
9 #include <linux/init.h>
10 #include <linux/cpufreq.h>
11 #include <linux/slab.h>
12 #include <linux/io.h>
13
14 #include <mach/generic.h>
15 #include <mach/pxa3xx-regs.h>
16
17 #define HSS_104M (0)
18 #define HSS_156M (1)
19 #define HSS_208M (2)
20 #define HSS_312M (3)
21
22 #define SMCFS_78M (0)
23 #define SMCFS_104M (2)
24 #define SMCFS_208M (5)
25
26 #define SFLFS_104M (0)
27 #define SFLFS_156M (1)
28 #define SFLFS_208M (2)
29 #define SFLFS_312M (3)
30
31 #define XSPCLK_156M (0)
32 #define XSPCLK_NONE (3)
33
34 #define DMCFS_26M (0)
35 #define DMCFS_260M (3)
36
37 struct pxa3xx_freq_info {
38 unsigned int cpufreq_mhz;
39 unsigned int core_xl : 5;
40 unsigned int core_xn : 3;
41 unsigned int hss : 2;
42 unsigned int dmcfs : 2;
43 unsigned int smcfs : 3;
44 unsigned int sflfs : 2;
45 unsigned int df_clkdiv : 3;
46
47 int vcc_core; /* in mV */
48 int vcc_sram; /* in mV */
49 };
50
51 #define OP(cpufreq, _xl, _xn, _hss, _dmc, _smc, _sfl, _dfi, vcore, vsram) \
52 { \
53 .cpufreq_mhz = cpufreq, \
54 .core_xl = _xl, \
55 .core_xn = _xn, \
56 .hss = HSS_##_hss##M, \
57 .dmcfs = DMCFS_##_dmc##M, \
58 .smcfs = SMCFS_##_smc##M, \
59 .sflfs = SFLFS_##_sfl##M, \
60 .df_clkdiv = _dfi, \
61 .vcc_core = vcore, \
62 .vcc_sram = vsram, \
63 }
64
65 static struct pxa3xx_freq_info pxa300_freqs[] = {
66 /* CPU XL XN HSS DMEM SMEM SRAM DFI VCC_CORE VCC_SRAM */
67 OP(104, 8, 1, 104, 260, 78, 104, 3, 1000, 1100), /* 104MHz */
68 OP(208, 16, 1, 104, 260, 104, 156, 2, 1000, 1100), /* 208MHz */
69 OP(416, 16, 2, 156, 260, 104, 208, 2, 1100, 1200), /* 416MHz */
70 OP(624, 24, 2, 208, 260, 208, 312, 3, 1375, 1400), /* 624MHz */
71 };
72
73 static struct pxa3xx_freq_info pxa320_freqs[] = {
74 /* CPU XL XN HSS DMEM SMEM SRAM DFI VCC_CORE VCC_SRAM */
75 OP(104, 8, 1, 104, 260, 78, 104, 3, 1000, 1100), /* 104MHz */
76 OP(208, 16, 1, 104, 260, 104, 156, 2, 1000, 1100), /* 208MHz */
77 OP(416, 16, 2, 156, 260, 104, 208, 2, 1100, 1200), /* 416MHz */
78 OP(624, 24, 2, 208, 260, 208, 312, 3, 1375, 1400), /* 624MHz */
79 OP(806, 31, 2, 208, 260, 208, 312, 3, 1400, 1400), /* 806MHz */
80 };
81
82 static unsigned int pxa3xx_freqs_num;
83 static struct pxa3xx_freq_info *pxa3xx_freqs;
84 static struct cpufreq_frequency_table *pxa3xx_freqs_table;
85
setup_freqs_table(struct cpufreq_policy * policy,struct pxa3xx_freq_info * freqs,int num)86 static int setup_freqs_table(struct cpufreq_policy *policy,
87 struct pxa3xx_freq_info *freqs, int num)
88 {
89 struct cpufreq_frequency_table *table;
90 int i;
91
92 table = kcalloc(num + 1, sizeof(*table), GFP_KERNEL);
93 if (table == NULL)
94 return -ENOMEM;
95
96 for (i = 0; i < num; i++) {
97 table[i].driver_data = i;
98 table[i].frequency = freqs[i].cpufreq_mhz * 1000;
99 }
100 table[num].driver_data = i;
101 table[num].frequency = CPUFREQ_TABLE_END;
102
103 pxa3xx_freqs = freqs;
104 pxa3xx_freqs_num = num;
105 pxa3xx_freqs_table = table;
106
107 policy->freq_table = table;
108
109 return 0;
110 }
111
__update_core_freq(struct pxa3xx_freq_info * info)112 static void __update_core_freq(struct pxa3xx_freq_info *info)
113 {
114 uint32_t mask = ACCR_XN_MASK | ACCR_XL_MASK;
115 uint32_t accr = ACCR;
116 uint32_t xclkcfg;
117
118 accr &= ~(ACCR_XN_MASK | ACCR_XL_MASK | ACCR_XSPCLK_MASK);
119 accr |= ACCR_XN(info->core_xn) | ACCR_XL(info->core_xl);
120
121 /* No clock until core PLL is re-locked */
122 accr |= ACCR_XSPCLK(XSPCLK_NONE);
123
124 xclkcfg = (info->core_xn == 2) ? 0x3 : 0x2; /* turbo bit */
125
126 ACCR = accr;
127 __asm__("mcr p14, 0, %0, c6, c0, 0\n" : : "r"(xclkcfg));
128
129 while ((ACSR & mask) != (accr & mask))
130 cpu_relax();
131 }
132
__update_bus_freq(struct pxa3xx_freq_info * info)133 static void __update_bus_freq(struct pxa3xx_freq_info *info)
134 {
135 uint32_t mask;
136 uint32_t accr = ACCR;
137
138 mask = ACCR_SMCFS_MASK | ACCR_SFLFS_MASK | ACCR_HSS_MASK |
139 ACCR_DMCFS_MASK;
140
141 accr &= ~mask;
142 accr |= ACCR_SMCFS(info->smcfs) | ACCR_SFLFS(info->sflfs) |
143 ACCR_HSS(info->hss) | ACCR_DMCFS(info->dmcfs);
144
145 ACCR = accr;
146
147 while ((ACSR & mask) != (accr & mask))
148 cpu_relax();
149 }
150
pxa3xx_cpufreq_get(unsigned int cpu)151 static unsigned int pxa3xx_cpufreq_get(unsigned int cpu)
152 {
153 return pxa3xx_get_clk_frequency_khz(0);
154 }
155
pxa3xx_cpufreq_set(struct cpufreq_policy * policy,unsigned int index)156 static int pxa3xx_cpufreq_set(struct cpufreq_policy *policy, unsigned int index)
157 {
158 struct pxa3xx_freq_info *next;
159 unsigned long flags;
160
161 if (policy->cpu != 0)
162 return -EINVAL;
163
164 next = &pxa3xx_freqs[index];
165
166 local_irq_save(flags);
167 __update_core_freq(next);
168 __update_bus_freq(next);
169 local_irq_restore(flags);
170
171 return 0;
172 }
173
pxa3xx_cpufreq_init(struct cpufreq_policy * policy)174 static int pxa3xx_cpufreq_init(struct cpufreq_policy *policy)
175 {
176 int ret = -EINVAL;
177
178 /* set default policy and cpuinfo */
179 policy->min = policy->cpuinfo.min_freq = 104000;
180 policy->max = policy->cpuinfo.max_freq =
181 (cpu_is_pxa320()) ? 806000 : 624000;
182 policy->cpuinfo.transition_latency = 1000; /* FIXME: 1 ms, assumed */
183
184 if (cpu_is_pxa300() || cpu_is_pxa310())
185 ret = setup_freqs_table(policy, pxa300_freqs,
186 ARRAY_SIZE(pxa300_freqs));
187
188 if (cpu_is_pxa320())
189 ret = setup_freqs_table(policy, pxa320_freqs,
190 ARRAY_SIZE(pxa320_freqs));
191
192 if (ret) {
193 pr_err("failed to setup frequency table\n");
194 return ret;
195 }
196
197 pr_info("CPUFREQ support for PXA3xx initialized\n");
198 return 0;
199 }
200
201 static struct cpufreq_driver pxa3xx_cpufreq_driver = {
202 .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
203 .verify = cpufreq_generic_frequency_table_verify,
204 .target_index = pxa3xx_cpufreq_set,
205 .init = pxa3xx_cpufreq_init,
206 .get = pxa3xx_cpufreq_get,
207 .name = "pxa3xx-cpufreq",
208 };
209
cpufreq_init(void)210 static int __init cpufreq_init(void)
211 {
212 if (cpu_is_pxa3xx())
213 return cpufreq_register_driver(&pxa3xx_cpufreq_driver);
214
215 return 0;
216 }
217 module_init(cpufreq_init);
218
cpufreq_exit(void)219 static void __exit cpufreq_exit(void)
220 {
221 cpufreq_unregister_driver(&pxa3xx_cpufreq_driver);
222 }
223 module_exit(cpufreq_exit);
224
225 MODULE_DESCRIPTION("CPU frequency scaling driver for PXA3xx");
226 MODULE_LICENSE("GPL");
227