Commit | Line | Data |
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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 | |
5d4879cd | 56 | opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz); |
1dd538f0 | 57 | if (IS_ERR(opp)) { |
1dd538f0 SG |
58 | dev_err(cpu_dev, "failed to find OPP for %ld\n", freq_hz); |
59 | return PTR_ERR(opp); | |
60 | } | |
61 | ||
5d4879cd | 62 | volt = dev_pm_opp_get_voltage(opp); |
8a31d9d9 VK |
63 | dev_pm_opp_put(opp); |
64 | ||
1dd538f0 SG |
65 | volt_old = regulator_get_voltage(arm_reg); |
66 | ||
67 | dev_dbg(cpu_dev, "%u MHz, %ld mV --> %u MHz, %ld mV\n", | |
d4019f0a VK |
68 | old_freq / 1000, volt_old / 1000, |
69 | new_freq / 1000, volt / 1000); | |
5a571c35 | 70 | |
1dd538f0 | 71 | /* scaling up? scale voltage before frequency */ |
d4019f0a | 72 | if (new_freq > old_freq) { |
22d0628a AH |
73 | if (!IS_ERR(pu_reg)) { |
74 | ret = regulator_set_voltage_tol(pu_reg, imx6_soc_volt[index], 0); | |
75 | if (ret) { | |
76 | dev_err(cpu_dev, "failed to scale vddpu up: %d\n", ret); | |
77 | return ret; | |
78 | } | |
b4573d1d AH |
79 | } |
80 | ret = regulator_set_voltage_tol(soc_reg, imx6_soc_volt[index], 0); | |
81 | if (ret) { | |
82 | dev_err(cpu_dev, "failed to scale vddsoc up: %d\n", ret); | |
83 | return ret; | |
84 | } | |
1dd538f0 SG |
85 | ret = regulator_set_voltage_tol(arm_reg, volt, 0); |
86 | if (ret) { | |
87 | dev_err(cpu_dev, | |
88 | "failed to scale vddarm up: %d\n", ret); | |
d4019f0a | 89 | return ret; |
1dd538f0 | 90 | } |
1dd538f0 SG |
91 | } |
92 | ||
93 | /* | |
94 | * The setpoints are selected per PLL/PDF frequencies, so we need to | |
95 | * reprogram PLL for frequency scaling. The procedure of reprogramming | |
96 | * PLL1 is as below. | |
a35fc5a3 BP |
97 | * For i.MX6UL, it has a secondary clk mux, the cpu frequency change |
98 | * flow is slightly different from other i.MX6 OSC. | |
99 | * The cpu frequeny change flow for i.MX6(except i.MX6UL) is as below: | |
1dd538f0 SG |
100 | * - Enable pll2_pfd2_396m_clk and reparent pll1_sw_clk to it |
101 | * - Reprogram pll1_sys_clk and reparent pll1_sw_clk back to it | |
102 | * - Disable pll2_pfd2_396m_clk | |
103 | */ | |
a35fc5a3 BP |
104 | if (of_machine_is_compatible("fsl,imx6ul")) { |
105 | /* | |
106 | * When changing pll1_sw_clk's parent to pll1_sys_clk, | |
107 | * CPU may run at higher than 528MHz, this will lead to | |
108 | * the system unstable if the voltage is lower than the | |
109 | * voltage of 528MHz, so lower the CPU frequency to one | |
110 | * half before changing CPU frequency. | |
111 | */ | |
112 | clk_set_rate(arm_clk, (old_freq >> 1) * 1000); | |
1dd538f0 | 113 | clk_set_parent(pll1_sw_clk, pll1_sys_clk); |
a35fc5a3 BP |
114 | if (freq_hz > clk_get_rate(pll2_pfd2_396m_clk)) |
115 | clk_set_parent(secondary_sel_clk, pll2_bus_clk); | |
116 | else | |
117 | clk_set_parent(secondary_sel_clk, pll2_pfd2_396m_clk); | |
118 | clk_set_parent(step_clk, secondary_sel_clk); | |
119 | clk_set_parent(pll1_sw_clk, step_clk); | |
120 | } else { | |
121 | clk_set_parent(step_clk, pll2_pfd2_396m_clk); | |
122 | clk_set_parent(pll1_sw_clk, step_clk); | |
123 | if (freq_hz > clk_get_rate(pll2_pfd2_396m_clk)) { | |
124 | clk_set_rate(pll1_sys_clk, new_freq * 1000); | |
125 | clk_set_parent(pll1_sw_clk, pll1_sys_clk); | |
126 | } | |
1dd538f0 SG |
127 | } |
128 | ||
129 | /* Ensure the arm clock divider is what we expect */ | |
d4019f0a | 130 | ret = clk_set_rate(arm_clk, new_freq * 1000); |
1dd538f0 SG |
131 | if (ret) { |
132 | dev_err(cpu_dev, "failed to set clock rate: %d\n", ret); | |
133 | regulator_set_voltage_tol(arm_reg, volt_old, 0); | |
d4019f0a | 134 | return ret; |
1dd538f0 SG |
135 | } |
136 | ||
137 | /* scaling down? scale voltage after frequency */ | |
d4019f0a | 138 | if (new_freq < old_freq) { |
1dd538f0 | 139 | ret = regulator_set_voltage_tol(arm_reg, volt, 0); |
5a571c35 | 140 | if (ret) { |
1dd538f0 SG |
141 | dev_warn(cpu_dev, |
142 | "failed to scale vddarm down: %d\n", ret); | |
5a571c35 VK |
143 | ret = 0; |
144 | } | |
b4573d1d AH |
145 | ret = regulator_set_voltage_tol(soc_reg, imx6_soc_volt[index], 0); |
146 | if (ret) { | |
147 | dev_warn(cpu_dev, "failed to scale vddsoc down: %d\n", ret); | |
148 | ret = 0; | |
149 | } | |
22d0628a AH |
150 | if (!IS_ERR(pu_reg)) { |
151 | ret = regulator_set_voltage_tol(pu_reg, imx6_soc_volt[index], 0); | |
152 | if (ret) { | |
153 | dev_warn(cpu_dev, "failed to scale vddpu down: %d\n", ret); | |
154 | ret = 0; | |
155 | } | |
1dd538f0 SG |
156 | } |
157 | } | |
158 | ||
d4019f0a | 159 | return 0; |
1dd538f0 SG |
160 | } |
161 | ||
162 | static int imx6q_cpufreq_init(struct cpufreq_policy *policy) | |
163 | { | |
652ed95d | 164 | policy->clk = arm_clk; |
17922ddd | 165 | return cpufreq_generic_init(policy, freq_table, transition_latency); |
1dd538f0 SG |
166 | } |
167 | ||
1dd538f0 | 168 | static struct cpufreq_driver imx6q_cpufreq_driver = { |
ae6b4271 | 169 | .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK, |
4f6ba385 | 170 | .verify = cpufreq_generic_frequency_table_verify, |
9c0ebcf7 | 171 | .target_index = imx6q_set_target, |
652ed95d | 172 | .get = cpufreq_generic_get, |
1dd538f0 | 173 | .init = imx6q_cpufreq_init, |
1dd538f0 | 174 | .name = "imx6q-cpufreq", |
4f6ba385 | 175 | .attr = cpufreq_generic_attr, |
1dd538f0 SG |
176 | }; |
177 | ||
178 | static int imx6q_cpufreq_probe(struct platform_device *pdev) | |
179 | { | |
180 | struct device_node *np; | |
47d43ba7 | 181 | struct dev_pm_opp *opp; |
1dd538f0 SG |
182 | unsigned long min_volt, max_volt; |
183 | int num, ret; | |
b4573d1d AH |
184 | const struct property *prop; |
185 | const __be32 *val; | |
186 | u32 nr, i, j; | |
1dd538f0 | 187 | |
b494b48d SK |
188 | cpu_dev = get_cpu_device(0); |
189 | if (!cpu_dev) { | |
190 | pr_err("failed to get cpu0 device\n"); | |
191 | return -ENODEV; | |
192 | } | |
1dd538f0 | 193 | |
cdc58d60 | 194 | np = of_node_get(cpu_dev->of_node); |
1dd538f0 SG |
195 | if (!np) { |
196 | dev_err(cpu_dev, "failed to find cpu0 node\n"); | |
197 | return -ENOENT; | |
198 | } | |
199 | ||
f8269c19 PZ |
200 | arm_clk = clk_get(cpu_dev, "arm"); |
201 | pll1_sys_clk = clk_get(cpu_dev, "pll1_sys"); | |
202 | pll1_sw_clk = clk_get(cpu_dev, "pll1_sw"); | |
203 | step_clk = clk_get(cpu_dev, "step"); | |
204 | pll2_pfd2_396m_clk = clk_get(cpu_dev, "pll2_pfd2_396m"); | |
1dd538f0 SG |
205 | if (IS_ERR(arm_clk) || IS_ERR(pll1_sys_clk) || IS_ERR(pll1_sw_clk) || |
206 | IS_ERR(step_clk) || IS_ERR(pll2_pfd2_396m_clk)) { | |
207 | dev_err(cpu_dev, "failed to get clocks\n"); | |
208 | ret = -ENOENT; | |
f8269c19 | 209 | goto put_clk; |
1dd538f0 SG |
210 | } |
211 | ||
a35fc5a3 BP |
212 | if (of_machine_is_compatible("fsl,imx6ul")) { |
213 | pll2_bus_clk = clk_get(cpu_dev, "pll2_bus"); | |
214 | secondary_sel_clk = clk_get(cpu_dev, "secondary_sel"); | |
215 | if (IS_ERR(pll2_bus_clk) || IS_ERR(secondary_sel_clk)) { | |
216 | dev_err(cpu_dev, "failed to get clocks specific to imx6ul\n"); | |
217 | ret = -ENOENT; | |
218 | goto put_clk; | |
219 | } | |
220 | } | |
221 | ||
f8269c19 | 222 | arm_reg = regulator_get(cpu_dev, "arm"); |
22d0628a | 223 | pu_reg = regulator_get_optional(cpu_dev, "pu"); |
f8269c19 | 224 | soc_reg = regulator_get(cpu_dev, "soc"); |
54cad2fc IT |
225 | if (PTR_ERR(arm_reg) == -EPROBE_DEFER || |
226 | PTR_ERR(soc_reg) == -EPROBE_DEFER || | |
227 | PTR_ERR(pu_reg) == -EPROBE_DEFER) { | |
228 | ret = -EPROBE_DEFER; | |
229 | dev_dbg(cpu_dev, "regulators not ready, defer\n"); | |
230 | goto put_reg; | |
231 | } | |
22d0628a | 232 | if (IS_ERR(arm_reg) || IS_ERR(soc_reg)) { |
1dd538f0 SG |
233 | dev_err(cpu_dev, "failed to get regulators\n"); |
234 | ret = -ENOENT; | |
f8269c19 | 235 | goto put_reg; |
1dd538f0 SG |
236 | } |
237 | ||
20b7cbe2 JT |
238 | /* |
239 | * We expect an OPP table supplied by platform. | |
240 | * Just, incase the platform did not supply the OPP | |
241 | * table, it will try to get it. | |
242 | */ | |
5d4879cd | 243 | num = dev_pm_opp_get_opp_count(cpu_dev); |
1dd538f0 | 244 | if (num < 0) { |
8f8d37b2 | 245 | ret = dev_pm_opp_of_add_table(cpu_dev); |
20b7cbe2 JT |
246 | if (ret < 0) { |
247 | dev_err(cpu_dev, "failed to init OPP table: %d\n", ret); | |
f8269c19 | 248 | goto put_reg; |
20b7cbe2 JT |
249 | } |
250 | ||
cc87b8a8 VK |
251 | /* Because we have added the OPPs here, we must free them */ |
252 | free_opp = true; | |
253 | ||
20b7cbe2 JT |
254 | num = dev_pm_opp_get_opp_count(cpu_dev); |
255 | if (num < 0) { | |
256 | ret = num; | |
257 | dev_err(cpu_dev, "no OPP table is found: %d\n", ret); | |
cc87b8a8 | 258 | goto out_free_opp; |
20b7cbe2 | 259 | } |
1dd538f0 SG |
260 | } |
261 | ||
5d4879cd | 262 | ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table); |
1dd538f0 SG |
263 | if (ret) { |
264 | dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret); | |
f8269c19 | 265 | goto put_reg; |
1dd538f0 SG |
266 | } |
267 | ||
b4573d1d AH |
268 | /* Make imx6_soc_volt array's size same as arm opp number */ |
269 | imx6_soc_volt = devm_kzalloc(cpu_dev, sizeof(*imx6_soc_volt) * num, GFP_KERNEL); | |
270 | if (imx6_soc_volt == NULL) { | |
271 | ret = -ENOMEM; | |
272 | goto free_freq_table; | |
273 | } | |
274 | ||
275 | prop = of_find_property(np, "fsl,soc-operating-points", NULL); | |
276 | if (!prop || !prop->value) | |
277 | goto soc_opp_out; | |
278 | ||
279 | /* | |
280 | * Each OPP is a set of tuples consisting of frequency and | |
281 | * voltage like <freq-kHz vol-uV>. | |
282 | */ | |
283 | nr = prop->length / sizeof(u32); | |
284 | if (nr % 2 || (nr / 2) < num) | |
285 | goto soc_opp_out; | |
286 | ||
287 | for (j = 0; j < num; j++) { | |
288 | val = prop->value; | |
289 | for (i = 0; i < nr / 2; i++) { | |
290 | unsigned long freq = be32_to_cpup(val++); | |
291 | unsigned long volt = be32_to_cpup(val++); | |
292 | if (freq_table[j].frequency == freq) { | |
293 | imx6_soc_volt[soc_opp_count++] = volt; | |
294 | break; | |
295 | } | |
296 | } | |
297 | } | |
298 | ||
299 | soc_opp_out: | |
300 | /* use fixed soc opp volt if no valid soc opp info found in dtb */ | |
301 | if (soc_opp_count != num) { | |
302 | dev_warn(cpu_dev, "can NOT find valid fsl,soc-operating-points property in dtb, use default value!\n"); | |
303 | for (j = 0; j < num; j++) | |
304 | imx6_soc_volt[j] = PU_SOC_VOLTAGE_NORMAL; | |
305 | if (freq_table[num - 1].frequency * 1000 == FREQ_1P2_GHZ) | |
306 | imx6_soc_volt[num - 1] = PU_SOC_VOLTAGE_HIGH; | |
307 | } | |
308 | ||
1dd538f0 SG |
309 | if (of_property_read_u32(np, "clock-latency", &transition_latency)) |
310 | transition_latency = CPUFREQ_ETERNAL; | |
311 | ||
b4573d1d AH |
312 | /* |
313 | * Calculate the ramp time for max voltage change in the | |
314 | * VDDSOC and VDDPU regulators. | |
315 | */ | |
316 | ret = regulator_set_voltage_time(soc_reg, imx6_soc_volt[0], imx6_soc_volt[num - 1]); | |
317 | if (ret > 0) | |
318 | transition_latency += ret * 1000; | |
22d0628a AH |
319 | if (!IS_ERR(pu_reg)) { |
320 | ret = regulator_set_voltage_time(pu_reg, imx6_soc_volt[0], imx6_soc_volt[num - 1]); | |
321 | if (ret > 0) | |
322 | transition_latency += ret * 1000; | |
323 | } | |
b4573d1d | 324 | |
1dd538f0 SG |
325 | /* |
326 | * OPP is maintained in order of increasing frequency, and | |
327 | * freq_table initialised from OPP is therefore sorted in the | |
328 | * same order. | |
329 | */ | |
5d4879cd | 330 | opp = dev_pm_opp_find_freq_exact(cpu_dev, |
1dd538f0 | 331 | freq_table[0].frequency * 1000, true); |
5d4879cd | 332 | min_volt = dev_pm_opp_get_voltage(opp); |
8a31d9d9 | 333 | dev_pm_opp_put(opp); |
5d4879cd | 334 | opp = dev_pm_opp_find_freq_exact(cpu_dev, |
1dd538f0 | 335 | freq_table[--num].frequency * 1000, true); |
5d4879cd | 336 | max_volt = dev_pm_opp_get_voltage(opp); |
8a31d9d9 VK |
337 | dev_pm_opp_put(opp); |
338 | ||
1dd538f0 SG |
339 | ret = regulator_set_voltage_time(arm_reg, min_volt, max_volt); |
340 | if (ret > 0) | |
341 | transition_latency += ret * 1000; | |
342 | ||
1dd538f0 SG |
343 | ret = cpufreq_register_driver(&imx6q_cpufreq_driver); |
344 | if (ret) { | |
345 | dev_err(cpu_dev, "failed register driver: %d\n", ret); | |
346 | goto free_freq_table; | |
347 | } | |
348 | ||
349 | of_node_put(np); | |
350 | return 0; | |
351 | ||
352 | free_freq_table: | |
5d4879cd | 353 | dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); |
cc87b8a8 VK |
354 | out_free_opp: |
355 | if (free_opp) | |
8f8d37b2 | 356 | dev_pm_opp_of_remove_table(cpu_dev); |
f8269c19 PZ |
357 | put_reg: |
358 | if (!IS_ERR(arm_reg)) | |
359 | regulator_put(arm_reg); | |
360 | if (!IS_ERR(pu_reg)) | |
361 | regulator_put(pu_reg); | |
362 | if (!IS_ERR(soc_reg)) | |
363 | regulator_put(soc_reg); | |
364 | put_clk: | |
365 | if (!IS_ERR(arm_clk)) | |
366 | clk_put(arm_clk); | |
367 | if (!IS_ERR(pll1_sys_clk)) | |
368 | clk_put(pll1_sys_clk); | |
369 | if (!IS_ERR(pll1_sw_clk)) | |
370 | clk_put(pll1_sw_clk); | |
371 | if (!IS_ERR(step_clk)) | |
372 | clk_put(step_clk); | |
373 | if (!IS_ERR(pll2_pfd2_396m_clk)) | |
374 | clk_put(pll2_pfd2_396m_clk); | |
a35fc5a3 BP |
375 | if (!IS_ERR(pll2_bus_clk)) |
376 | clk_put(pll2_bus_clk); | |
377 | if (!IS_ERR(secondary_sel_clk)) | |
378 | clk_put(secondary_sel_clk); | |
1dd538f0 SG |
379 | of_node_put(np); |
380 | return ret; | |
381 | } | |
382 | ||
383 | static int imx6q_cpufreq_remove(struct platform_device *pdev) | |
384 | { | |
385 | cpufreq_unregister_driver(&imx6q_cpufreq_driver); | |
5d4879cd | 386 | dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); |
cc87b8a8 | 387 | if (free_opp) |
8f8d37b2 | 388 | dev_pm_opp_of_remove_table(cpu_dev); |
f8269c19 | 389 | regulator_put(arm_reg); |
22d0628a AH |
390 | if (!IS_ERR(pu_reg)) |
391 | regulator_put(pu_reg); | |
f8269c19 PZ |
392 | regulator_put(soc_reg); |
393 | clk_put(arm_clk); | |
394 | clk_put(pll1_sys_clk); | |
395 | clk_put(pll1_sw_clk); | |
396 | clk_put(step_clk); | |
397 | clk_put(pll2_pfd2_396m_clk); | |
a35fc5a3 BP |
398 | clk_put(pll2_bus_clk); |
399 | clk_put(secondary_sel_clk); | |
1dd538f0 SG |
400 | |
401 | return 0; | |
402 | } | |
403 | ||
404 | static struct platform_driver imx6q_cpufreq_platdrv = { | |
405 | .driver = { | |
406 | .name = "imx6q-cpufreq", | |
1dd538f0 SG |
407 | }, |
408 | .probe = imx6q_cpufreq_probe, | |
409 | .remove = imx6q_cpufreq_remove, | |
410 | }; | |
411 | module_platform_driver(imx6q_cpufreq_platdrv); | |
412 | ||
413 | MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>"); | |
414 | MODULE_DESCRIPTION("Freescale i.MX6Q cpufreq driver"); | |
415 | MODULE_LICENSE("GPL"); |