Commit | Line | Data |
---|---|---|
1dd538f0 SG |
1 | /* |
2 | * Copyright (C) 2013 Freescale Semiconductor, Inc. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License version 2 as | |
6 | * published by the Free Software Foundation. | |
7 | */ | |
8 | ||
9 | #include <linux/clk.h> | |
b494b48d | 10 | #include <linux/cpu.h> |
1dd538f0 | 11 | #include <linux/cpufreq.h> |
1dd538f0 SG |
12 | #include <linux/err.h> |
13 | #include <linux/module.h> | |
14 | #include <linux/of.h> | |
e4db1c74 | 15 | #include <linux/pm_opp.h> |
1dd538f0 SG |
16 | #include <linux/platform_device.h> |
17 | #include <linux/regulator/consumer.h> | |
18 | ||
19 | #define PU_SOC_VOLTAGE_NORMAL 1250000 | |
20 | #define PU_SOC_VOLTAGE_HIGH 1275000 | |
21 | #define FREQ_1P2_GHZ 1200000000 | |
22 | ||
23 | static struct regulator *arm_reg; | |
24 | static struct regulator *pu_reg; | |
25 | static struct regulator *soc_reg; | |
26 | ||
27 | static struct clk *arm_clk; | |
28 | static struct clk *pll1_sys_clk; | |
29 | static struct clk *pll1_sw_clk; | |
30 | static struct clk *step_clk; | |
31 | static struct clk *pll2_pfd2_396m_clk; | |
32 | ||
a35fc5a3 BP |
33 | /* clk used by i.MX6UL */ |
34 | static struct clk *pll2_bus_clk; | |
35 | static struct clk *secondary_sel_clk; | |
36 | ||
1dd538f0 | 37 | static struct device *cpu_dev; |
cc87b8a8 | 38 | static bool free_opp; |
1dd538f0 SG |
39 | static struct cpufreq_frequency_table *freq_table; |
40 | static unsigned int transition_latency; | |
41 | ||
b4573d1d AH |
42 | static u32 *imx6_soc_volt; |
43 | static u32 soc_opp_count; | |
44 | ||
9c0ebcf7 | 45 | static int imx6q_set_target(struct cpufreq_policy *policy, unsigned int index) |
1dd538f0 | 46 | { |
47d43ba7 | 47 | struct dev_pm_opp *opp; |
1dd538f0 | 48 | unsigned long freq_hz, volt, volt_old; |
d4019f0a | 49 | unsigned int old_freq, new_freq; |
1dd538f0 SG |
50 | int ret; |
51 | ||
d4019f0a VK |
52 | new_freq = freq_table[index].frequency; |
53 | freq_hz = new_freq * 1000; | |
54 | old_freq = clk_get_rate(arm_clk) / 1000; | |
1dd538f0 | 55 | |
1dd538f0 | 56 | rcu_read_lock(); |
5d4879cd | 57 | opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz); |
1dd538f0 SG |
58 | if (IS_ERR(opp)) { |
59 | rcu_read_unlock(); | |
60 | dev_err(cpu_dev, "failed to find OPP for %ld\n", freq_hz); | |
61 | return PTR_ERR(opp); | |
62 | } | |
63 | ||
5d4879cd | 64 | volt = dev_pm_opp_get_voltage(opp); |
1dd538f0 SG |
65 | rcu_read_unlock(); |
66 | volt_old = regulator_get_voltage(arm_reg); | |
67 | ||
68 | dev_dbg(cpu_dev, "%u MHz, %ld mV --> %u MHz, %ld mV\n", | |
d4019f0a VK |
69 | old_freq / 1000, volt_old / 1000, |
70 | new_freq / 1000, volt / 1000); | |
5a571c35 | 71 | |
1dd538f0 | 72 | /* scaling up? scale voltage before frequency */ |
d4019f0a | 73 | if (new_freq > old_freq) { |
22d0628a AH |
74 | if (!IS_ERR(pu_reg)) { |
75 | ret = regulator_set_voltage_tol(pu_reg, imx6_soc_volt[index], 0); | |
76 | if (ret) { | |
77 | dev_err(cpu_dev, "failed to scale vddpu up: %d\n", ret); | |
78 | return ret; | |
79 | } | |
b4573d1d AH |
80 | } |
81 | ret = regulator_set_voltage_tol(soc_reg, imx6_soc_volt[index], 0); | |
82 | if (ret) { | |
83 | dev_err(cpu_dev, "failed to scale vddsoc up: %d\n", ret); | |
84 | return ret; | |
85 | } | |
1dd538f0 SG |
86 | ret = regulator_set_voltage_tol(arm_reg, volt, 0); |
87 | if (ret) { | |
88 | dev_err(cpu_dev, | |
89 | "failed to scale vddarm up: %d\n", ret); | |
d4019f0a | 90 | return ret; |
1dd538f0 | 91 | } |
1dd538f0 SG |
92 | } |
93 | ||
94 | /* | |
95 | * The setpoints are selected per PLL/PDF frequencies, so we need to | |
96 | * reprogram PLL for frequency scaling. The procedure of reprogramming | |
97 | * PLL1 is as below. | |
a35fc5a3 BP |
98 | * For i.MX6UL, it has a secondary clk mux, the cpu frequency change |
99 | * flow is slightly different from other i.MX6 OSC. | |
100 | * The cpu frequeny change flow for i.MX6(except i.MX6UL) is as below: | |
1dd538f0 SG |
101 | * - Enable pll2_pfd2_396m_clk and reparent pll1_sw_clk to it |
102 | * - Reprogram pll1_sys_clk and reparent pll1_sw_clk back to it | |
103 | * - Disable pll2_pfd2_396m_clk | |
104 | */ | |
a35fc5a3 BP |
105 | if (of_machine_is_compatible("fsl,imx6ul")) { |
106 | /* | |
107 | * When changing pll1_sw_clk's parent to pll1_sys_clk, | |
108 | * CPU may run at higher than 528MHz, this will lead to | |
109 | * the system unstable if the voltage is lower than the | |
110 | * voltage of 528MHz, so lower the CPU frequency to one | |
111 | * half before changing CPU frequency. | |
112 | */ | |
113 | clk_set_rate(arm_clk, (old_freq >> 1) * 1000); | |
1dd538f0 | 114 | clk_set_parent(pll1_sw_clk, pll1_sys_clk); |
a35fc5a3 BP |
115 | if (freq_hz > clk_get_rate(pll2_pfd2_396m_clk)) |
116 | clk_set_parent(secondary_sel_clk, pll2_bus_clk); | |
117 | else | |
118 | clk_set_parent(secondary_sel_clk, pll2_pfd2_396m_clk); | |
119 | clk_set_parent(step_clk, secondary_sel_clk); | |
120 | clk_set_parent(pll1_sw_clk, step_clk); | |
121 | } else { | |
122 | clk_set_parent(step_clk, pll2_pfd2_396m_clk); | |
123 | clk_set_parent(pll1_sw_clk, step_clk); | |
124 | if (freq_hz > clk_get_rate(pll2_pfd2_396m_clk)) { | |
125 | clk_set_rate(pll1_sys_clk, new_freq * 1000); | |
126 | clk_set_parent(pll1_sw_clk, pll1_sys_clk); | |
127 | } | |
1dd538f0 SG |
128 | } |
129 | ||
130 | /* Ensure the arm clock divider is what we expect */ | |
d4019f0a | 131 | ret = clk_set_rate(arm_clk, new_freq * 1000); |
1dd538f0 SG |
132 | if (ret) { |
133 | dev_err(cpu_dev, "failed to set clock rate: %d\n", ret); | |
134 | regulator_set_voltage_tol(arm_reg, volt_old, 0); | |
d4019f0a | 135 | return ret; |
1dd538f0 SG |
136 | } |
137 | ||
138 | /* scaling down? scale voltage after frequency */ | |
d4019f0a | 139 | if (new_freq < old_freq) { |
1dd538f0 | 140 | ret = regulator_set_voltage_tol(arm_reg, volt, 0); |
5a571c35 | 141 | if (ret) { |
1dd538f0 SG |
142 | dev_warn(cpu_dev, |
143 | "failed to scale vddarm down: %d\n", ret); | |
5a571c35 VK |
144 | ret = 0; |
145 | } | |
b4573d1d AH |
146 | ret = regulator_set_voltage_tol(soc_reg, imx6_soc_volt[index], 0); |
147 | if (ret) { | |
148 | dev_warn(cpu_dev, "failed to scale vddsoc down: %d\n", ret); | |
149 | ret = 0; | |
150 | } | |
22d0628a AH |
151 | if (!IS_ERR(pu_reg)) { |
152 | ret = regulator_set_voltage_tol(pu_reg, imx6_soc_volt[index], 0); | |
153 | if (ret) { | |
154 | dev_warn(cpu_dev, "failed to scale vddpu down: %d\n", ret); | |
155 | ret = 0; | |
156 | } | |
1dd538f0 SG |
157 | } |
158 | } | |
159 | ||
d4019f0a | 160 | return 0; |
1dd538f0 SG |
161 | } |
162 | ||
163 | static int imx6q_cpufreq_init(struct cpufreq_policy *policy) | |
164 | { | |
652ed95d | 165 | policy->clk = arm_clk; |
17922ddd | 166 | return cpufreq_generic_init(policy, freq_table, transition_latency); |
1dd538f0 SG |
167 | } |
168 | ||
1dd538f0 | 169 | static struct cpufreq_driver imx6q_cpufreq_driver = { |
ae6b4271 | 170 | .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, |
4f6ba385 | 171 | .verify = cpufreq_generic_frequency_table_verify, |
9c0ebcf7 | 172 | .target_index = imx6q_set_target, |
652ed95d | 173 | .get = cpufreq_generic_get, |
1dd538f0 | 174 | .init = imx6q_cpufreq_init, |
1dd538f0 | 175 | .name = "imx6q-cpufreq", |
4f6ba385 | 176 | .attr = cpufreq_generic_attr, |
1dd538f0 SG |
177 | }; |
178 | ||
179 | static int imx6q_cpufreq_probe(struct platform_device *pdev) | |
180 | { | |
181 | struct device_node *np; | |
47d43ba7 | 182 | struct dev_pm_opp *opp; |
1dd538f0 SG |
183 | unsigned long min_volt, max_volt; |
184 | int num, ret; | |
b4573d1d AH |
185 | const struct property *prop; |
186 | const __be32 *val; | |
187 | u32 nr, i, j; | |
1dd538f0 | 188 | |
b494b48d SK |
189 | cpu_dev = get_cpu_device(0); |
190 | if (!cpu_dev) { | |
191 | pr_err("failed to get cpu0 device\n"); | |
192 | return -ENODEV; | |
193 | } | |
1dd538f0 | 194 | |
cdc58d60 | 195 | np = of_node_get(cpu_dev->of_node); |
1dd538f0 SG |
196 | if (!np) { |
197 | dev_err(cpu_dev, "failed to find cpu0 node\n"); | |
198 | return -ENOENT; | |
199 | } | |
200 | ||
f8269c19 PZ |
201 | arm_clk = clk_get(cpu_dev, "arm"); |
202 | pll1_sys_clk = clk_get(cpu_dev, "pll1_sys"); | |
203 | pll1_sw_clk = clk_get(cpu_dev, "pll1_sw"); | |
204 | step_clk = clk_get(cpu_dev, "step"); | |
205 | pll2_pfd2_396m_clk = clk_get(cpu_dev, "pll2_pfd2_396m"); | |
1dd538f0 SG |
206 | if (IS_ERR(arm_clk) || IS_ERR(pll1_sys_clk) || IS_ERR(pll1_sw_clk) || |
207 | IS_ERR(step_clk) || IS_ERR(pll2_pfd2_396m_clk)) { | |
208 | dev_err(cpu_dev, "failed to get clocks\n"); | |
209 | ret = -ENOENT; | |
f8269c19 | 210 | goto put_clk; |
1dd538f0 SG |
211 | } |
212 | ||
a35fc5a3 BP |
213 | if (of_machine_is_compatible("fsl,imx6ul")) { |
214 | pll2_bus_clk = clk_get(cpu_dev, "pll2_bus"); | |
215 | secondary_sel_clk = clk_get(cpu_dev, "secondary_sel"); | |
216 | if (IS_ERR(pll2_bus_clk) || IS_ERR(secondary_sel_clk)) { | |
217 | dev_err(cpu_dev, "failed to get clocks specific to imx6ul\n"); | |
218 | ret = -ENOENT; | |
219 | goto put_clk; | |
220 | } | |
221 | } | |
222 | ||
f8269c19 | 223 | arm_reg = regulator_get(cpu_dev, "arm"); |
22d0628a | 224 | pu_reg = regulator_get_optional(cpu_dev, "pu"); |
f8269c19 | 225 | soc_reg = regulator_get(cpu_dev, "soc"); |
22d0628a | 226 | if (IS_ERR(arm_reg) || IS_ERR(soc_reg)) { |
1dd538f0 SG |
227 | dev_err(cpu_dev, "failed to get regulators\n"); |
228 | ret = -ENOENT; | |
f8269c19 | 229 | goto put_reg; |
1dd538f0 SG |
230 | } |
231 | ||
20b7cbe2 JT |
232 | /* |
233 | * We expect an OPP table supplied by platform. | |
234 | * Just, incase the platform did not supply the OPP | |
235 | * table, it will try to get it. | |
236 | */ | |
5d4879cd | 237 | num = dev_pm_opp_get_opp_count(cpu_dev); |
1dd538f0 | 238 | if (num < 0) { |
8f8d37b2 | 239 | ret = dev_pm_opp_of_add_table(cpu_dev); |
20b7cbe2 JT |
240 | if (ret < 0) { |
241 | dev_err(cpu_dev, "failed to init OPP table: %d\n", ret); | |
f8269c19 | 242 | goto put_reg; |
20b7cbe2 JT |
243 | } |
244 | ||
cc87b8a8 VK |
245 | /* Because we have added the OPPs here, we must free them */ |
246 | free_opp = true; | |
247 | ||
20b7cbe2 JT |
248 | num = dev_pm_opp_get_opp_count(cpu_dev); |
249 | if (num < 0) { | |
250 | ret = num; | |
251 | dev_err(cpu_dev, "no OPP table is found: %d\n", ret); | |
cc87b8a8 | 252 | goto out_free_opp; |
20b7cbe2 | 253 | } |
1dd538f0 SG |
254 | } |
255 | ||
5d4879cd | 256 | ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table); |
1dd538f0 SG |
257 | if (ret) { |
258 | dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret); | |
f8269c19 | 259 | goto put_reg; |
1dd538f0 SG |
260 | } |
261 | ||
b4573d1d AH |
262 | /* Make imx6_soc_volt array's size same as arm opp number */ |
263 | imx6_soc_volt = devm_kzalloc(cpu_dev, sizeof(*imx6_soc_volt) * num, GFP_KERNEL); | |
264 | if (imx6_soc_volt == NULL) { | |
265 | ret = -ENOMEM; | |
266 | goto free_freq_table; | |
267 | } | |
268 | ||
269 | prop = of_find_property(np, "fsl,soc-operating-points", NULL); | |
270 | if (!prop || !prop->value) | |
271 | goto soc_opp_out; | |
272 | ||
273 | /* | |
274 | * Each OPP is a set of tuples consisting of frequency and | |
275 | * voltage like <freq-kHz vol-uV>. | |
276 | */ | |
277 | nr = prop->length / sizeof(u32); | |
278 | if (nr % 2 || (nr / 2) < num) | |
279 | goto soc_opp_out; | |
280 | ||
281 | for (j = 0; j < num; j++) { | |
282 | val = prop->value; | |
283 | for (i = 0; i < nr / 2; i++) { | |
284 | unsigned long freq = be32_to_cpup(val++); | |
285 | unsigned long volt = be32_to_cpup(val++); | |
286 | if (freq_table[j].frequency == freq) { | |
287 | imx6_soc_volt[soc_opp_count++] = volt; | |
288 | break; | |
289 | } | |
290 | } | |
291 | } | |
292 | ||
293 | soc_opp_out: | |
294 | /* use fixed soc opp volt if no valid soc opp info found in dtb */ | |
295 | if (soc_opp_count != num) { | |
296 | dev_warn(cpu_dev, "can NOT find valid fsl,soc-operating-points property in dtb, use default value!\n"); | |
297 | for (j = 0; j < num; j++) | |
298 | imx6_soc_volt[j] = PU_SOC_VOLTAGE_NORMAL; | |
299 | if (freq_table[num - 1].frequency * 1000 == FREQ_1P2_GHZ) | |
300 | imx6_soc_volt[num - 1] = PU_SOC_VOLTAGE_HIGH; | |
301 | } | |
302 | ||
1dd538f0 SG |
303 | if (of_property_read_u32(np, "clock-latency", &transition_latency)) |
304 | transition_latency = CPUFREQ_ETERNAL; | |
305 | ||
b4573d1d AH |
306 | /* |
307 | * Calculate the ramp time for max voltage change in the | |
308 | * VDDSOC and VDDPU regulators. | |
309 | */ | |
310 | ret = regulator_set_voltage_time(soc_reg, imx6_soc_volt[0], imx6_soc_volt[num - 1]); | |
311 | if (ret > 0) | |
312 | transition_latency += ret * 1000; | |
22d0628a AH |
313 | if (!IS_ERR(pu_reg)) { |
314 | ret = regulator_set_voltage_time(pu_reg, imx6_soc_volt[0], imx6_soc_volt[num - 1]); | |
315 | if (ret > 0) | |
316 | transition_latency += ret * 1000; | |
317 | } | |
b4573d1d | 318 | |
1dd538f0 SG |
319 | /* |
320 | * OPP is maintained in order of increasing frequency, and | |
321 | * freq_table initialised from OPP is therefore sorted in the | |
322 | * same order. | |
323 | */ | |
324 | rcu_read_lock(); | |
5d4879cd | 325 | opp = dev_pm_opp_find_freq_exact(cpu_dev, |
1dd538f0 | 326 | freq_table[0].frequency * 1000, true); |
5d4879cd NM |
327 | min_volt = dev_pm_opp_get_voltage(opp); |
328 | opp = dev_pm_opp_find_freq_exact(cpu_dev, | |
1dd538f0 | 329 | freq_table[--num].frequency * 1000, true); |
5d4879cd | 330 | max_volt = dev_pm_opp_get_voltage(opp); |
1dd538f0 SG |
331 | rcu_read_unlock(); |
332 | ret = regulator_set_voltage_time(arm_reg, min_volt, max_volt); | |
333 | if (ret > 0) | |
334 | transition_latency += ret * 1000; | |
335 | ||
1dd538f0 SG |
336 | ret = cpufreq_register_driver(&imx6q_cpufreq_driver); |
337 | if (ret) { | |
338 | dev_err(cpu_dev, "failed register driver: %d\n", ret); | |
339 | goto free_freq_table; | |
340 | } | |
341 | ||
342 | of_node_put(np); | |
343 | return 0; | |
344 | ||
345 | free_freq_table: | |
5d4879cd | 346 | dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); |
cc87b8a8 VK |
347 | out_free_opp: |
348 | if (free_opp) | |
8f8d37b2 | 349 | dev_pm_opp_of_remove_table(cpu_dev); |
f8269c19 PZ |
350 | put_reg: |
351 | if (!IS_ERR(arm_reg)) | |
352 | regulator_put(arm_reg); | |
353 | if (!IS_ERR(pu_reg)) | |
354 | regulator_put(pu_reg); | |
355 | if (!IS_ERR(soc_reg)) | |
356 | regulator_put(soc_reg); | |
357 | put_clk: | |
358 | if (!IS_ERR(arm_clk)) | |
359 | clk_put(arm_clk); | |
360 | if (!IS_ERR(pll1_sys_clk)) | |
361 | clk_put(pll1_sys_clk); | |
362 | if (!IS_ERR(pll1_sw_clk)) | |
363 | clk_put(pll1_sw_clk); | |
364 | if (!IS_ERR(step_clk)) | |
365 | clk_put(step_clk); | |
366 | if (!IS_ERR(pll2_pfd2_396m_clk)) | |
367 | clk_put(pll2_pfd2_396m_clk); | |
a35fc5a3 BP |
368 | if (!IS_ERR(pll2_bus_clk)) |
369 | clk_put(pll2_bus_clk); | |
370 | if (!IS_ERR(secondary_sel_clk)) | |
371 | clk_put(secondary_sel_clk); | |
1dd538f0 SG |
372 | of_node_put(np); |
373 | return ret; | |
374 | } | |
375 | ||
376 | static int imx6q_cpufreq_remove(struct platform_device *pdev) | |
377 | { | |
378 | cpufreq_unregister_driver(&imx6q_cpufreq_driver); | |
5d4879cd | 379 | dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); |
cc87b8a8 | 380 | if (free_opp) |
8f8d37b2 | 381 | dev_pm_opp_of_remove_table(cpu_dev); |
f8269c19 | 382 | regulator_put(arm_reg); |
22d0628a AH |
383 | if (!IS_ERR(pu_reg)) |
384 | regulator_put(pu_reg); | |
f8269c19 PZ |
385 | regulator_put(soc_reg); |
386 | clk_put(arm_clk); | |
387 | clk_put(pll1_sys_clk); | |
388 | clk_put(pll1_sw_clk); | |
389 | clk_put(step_clk); | |
390 | clk_put(pll2_pfd2_396m_clk); | |
a35fc5a3 BP |
391 | clk_put(pll2_bus_clk); |
392 | clk_put(secondary_sel_clk); | |
1dd538f0 SG |
393 | |
394 | return 0; | |
395 | } | |
396 | ||
397 | static struct platform_driver imx6q_cpufreq_platdrv = { | |
398 | .driver = { | |
399 | .name = "imx6q-cpufreq", | |
1dd538f0 SG |
400 | }, |
401 | .probe = imx6q_cpufreq_probe, | |
402 | .remove = imx6q_cpufreq_remove, | |
403 | }; | |
404 | module_platform_driver(imx6q_cpufreq_platdrv); | |
405 | ||
406 | MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>"); | |
407 | MODULE_DESCRIPTION("Freescale i.MX6Q cpufreq driver"); | |
408 | MODULE_LICENSE("GPL"); |