2 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
3 * http://www.samsung.com
5 * CPU frequency scaling for S5PC110/S5PV210
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/err.h>
16 #include <linux/clk.h>
18 #include <linux/cpufreq.h>
20 #include <linux/of_address.h>
21 #include <linux/platform_device.h>
22 #include <linux/reboot.h>
23 #include <linux/regulator/consumer.h>
25 static void __iomem *clk_base;
26 static void __iomem *dmc_base[2];
28 #define S5P_CLKREG(x) (clk_base + (x))
30 #define S5P_APLL_LOCK S5P_CLKREG(0x00)
31 #define S5P_APLL_CON S5P_CLKREG(0x100)
32 #define S5P_CLK_SRC0 S5P_CLKREG(0x200)
33 #define S5P_CLK_SRC2 S5P_CLKREG(0x208)
34 #define S5P_CLK_DIV0 S5P_CLKREG(0x300)
35 #define S5P_CLK_DIV2 S5P_CLKREG(0x308)
36 #define S5P_CLK_DIV6 S5P_CLKREG(0x318)
37 #define S5P_CLKDIV_STAT0 S5P_CLKREG(0x1000)
38 #define S5P_CLKDIV_STAT1 S5P_CLKREG(0x1004)
39 #define S5P_CLKMUX_STAT0 S5P_CLKREG(0x1100)
40 #define S5P_CLKMUX_STAT1 S5P_CLKREG(0x1104)
42 #define S5P_ARM_MCS_CON S5P_CLKREG(0x6100)
45 #define S5P_CLKSRC0_MUX200_SHIFT (16)
46 #define S5P_CLKSRC0_MUX200_MASK (0x1 << S5P_CLKSRC0_MUX200_SHIFT)
47 #define S5P_CLKSRC0_MUX166_MASK (0x1<<20)
48 #define S5P_CLKSRC0_MUX133_MASK (0x1<<24)
51 #define S5P_CLKSRC2_G3D_SHIFT (0)
52 #define S5P_CLKSRC2_G3D_MASK (0x3 << S5P_CLKSRC2_G3D_SHIFT)
53 #define S5P_CLKSRC2_MFC_SHIFT (4)
54 #define S5P_CLKSRC2_MFC_MASK (0x3 << S5P_CLKSRC2_MFC_SHIFT)
57 #define S5P_CLKDIV0_APLL_SHIFT (0)
58 #define S5P_CLKDIV0_APLL_MASK (0x7 << S5P_CLKDIV0_APLL_SHIFT)
59 #define S5P_CLKDIV0_A2M_SHIFT (4)
60 #define S5P_CLKDIV0_A2M_MASK (0x7 << S5P_CLKDIV0_A2M_SHIFT)
61 #define S5P_CLKDIV0_HCLK200_SHIFT (8)
62 #define S5P_CLKDIV0_HCLK200_MASK (0x7 << S5P_CLKDIV0_HCLK200_SHIFT)
63 #define S5P_CLKDIV0_PCLK100_SHIFT (12)
64 #define S5P_CLKDIV0_PCLK100_MASK (0x7 << S5P_CLKDIV0_PCLK100_SHIFT)
65 #define S5P_CLKDIV0_HCLK166_SHIFT (16)
66 #define S5P_CLKDIV0_HCLK166_MASK (0xF << S5P_CLKDIV0_HCLK166_SHIFT)
67 #define S5P_CLKDIV0_PCLK83_SHIFT (20)
68 #define S5P_CLKDIV0_PCLK83_MASK (0x7 << S5P_CLKDIV0_PCLK83_SHIFT)
69 #define S5P_CLKDIV0_HCLK133_SHIFT (24)
70 #define S5P_CLKDIV0_HCLK133_MASK (0xF << S5P_CLKDIV0_HCLK133_SHIFT)
71 #define S5P_CLKDIV0_PCLK66_SHIFT (28)
72 #define S5P_CLKDIV0_PCLK66_MASK (0x7 << S5P_CLKDIV0_PCLK66_SHIFT)
75 #define S5P_CLKDIV2_G3D_SHIFT (0)
76 #define S5P_CLKDIV2_G3D_MASK (0xF << S5P_CLKDIV2_G3D_SHIFT)
77 #define S5P_CLKDIV2_MFC_SHIFT (4)
78 #define S5P_CLKDIV2_MFC_MASK (0xF << S5P_CLKDIV2_MFC_SHIFT)
81 #define S5P_CLKDIV6_ONEDRAM_SHIFT (28)
82 #define S5P_CLKDIV6_ONEDRAM_MASK (0xF << S5P_CLKDIV6_ONEDRAM_SHIFT)
84 static struct clk *dmc0_clk;
85 static struct clk *dmc1_clk;
86 static DEFINE_MUTEX(set_freq_lock);
88 /* APLL M,P,S values for 1G/800Mhz */
89 #define APLL_VAL_1000 ((1 << 31) | (125 << 16) | (3 << 8) | 1)
90 #define APLL_VAL_800 ((1 << 31) | (100 << 16) | (3 << 8) | 1)
92 /* Use 800MHz when entering sleep mode */
93 #define SLEEP_FREQ (800 * 1000)
95 /* Tracks if cpu freqency can be updated anymore */
96 static bool no_cpufreq_access;
99 * DRAM configurations to calculate refresh counter for changing
100 * frequency of memory.
103 unsigned long freq; /* HZ */
104 unsigned long refresh; /* DRAM refresh counter * 1000 */
107 /* DRAM configuration (DMC0 and DMC1) */
108 static struct dram_conf s5pv210_dram_conf[2];
114 enum s5pv210_mem_type {
120 enum s5pv210_dmc_port {
125 static struct cpufreq_frequency_table s5pv210_freq_table[] = {
131 {0, 0, CPUFREQ_TABLE_END},
134 static struct regulator *arm_regulator;
135 static struct regulator *int_regulator;
137 struct s5pv210_dvs_conf {
138 int arm_volt; /* uV */
139 int int_volt; /* uV */
142 static const int arm_volt_max = 1350000;
143 static const int int_volt_max = 1250000;
145 static struct s5pv210_dvs_conf dvs_conf[] = {
168 static u32 clkdiv_val[5][11] = {
170 * Clock divider value for following
171 * { APLL, A2M, HCLK_MSYS, PCLK_MSYS,
172 * HCLK_DSYS, PCLK_DSYS, HCLK_PSYS, PCLK_PSYS,
173 * ONEDRAM, MFC, G3D }
176 /* L0 : [1000/200/100][166/83][133/66][200/200] */
177 {0, 4, 4, 1, 3, 1, 4, 1, 3, 0, 0},
179 /* L1 : [800/200/100][166/83][133/66][200/200] */
180 {0, 3, 3, 1, 3, 1, 4, 1, 3, 0, 0},
182 /* L2 : [400/200/100][166/83][133/66][200/200] */
183 {1, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
185 /* L3 : [200/200/100][166/83][133/66][200/200] */
186 {3, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
188 /* L4 : [100/100/100][83/83][66/66][100/100] */
189 {7, 7, 0, 0, 7, 0, 9, 0, 7, 0, 0},
193 * This function set DRAM refresh counter
194 * accoriding to operating frequency of DRAM
195 * ch: DMC port number 0 or 1
196 * freq: Operating frequency of DRAM(KHz)
198 static void s5pv210_set_refresh(enum s5pv210_dmc_port ch, unsigned long freq)
200 unsigned long tmp, tmp1;
201 void __iomem *reg = NULL;
204 reg = (dmc_base[0] + 0x30);
205 } else if (ch == DMC1) {
206 reg = (dmc_base[1] + 0x30);
208 printk(KERN_ERR "Cannot find DMC port\n");
212 /* Find current DRAM frequency */
213 tmp = s5pv210_dram_conf[ch].freq;
217 tmp1 = s5pv210_dram_conf[ch].refresh;
221 __raw_writel(tmp1, reg);
224 static int s5pv210_target(struct cpufreq_policy *policy, unsigned int index)
227 unsigned int priv_index;
228 unsigned int pll_changing = 0;
229 unsigned int bus_speed_changing = 0;
230 unsigned int old_freq, new_freq;
231 int arm_volt, int_volt;
234 mutex_lock(&set_freq_lock);
236 if (no_cpufreq_access) {
237 pr_err("Denied access to %s as it is disabled temporarily\n",
243 old_freq = policy->cur;
244 new_freq = s5pv210_freq_table[index].frequency;
246 /* Finding current running level index */
247 if (cpufreq_frequency_table_target(policy, s5pv210_freq_table,
248 old_freq, CPUFREQ_RELATION_H,
254 arm_volt = dvs_conf[index].arm_volt;
255 int_volt = dvs_conf[index].int_volt;
257 if (new_freq > old_freq) {
258 ret = regulator_set_voltage(arm_regulator,
259 arm_volt, arm_volt_max);
263 ret = regulator_set_voltage(int_regulator,
264 int_volt, int_volt_max);
269 /* Check if there need to change PLL */
270 if ((index == L0) || (priv_index == L0))
273 /* Check if there need to change System bus clock */
274 if ((index == L4) || (priv_index == L4))
275 bus_speed_changing = 1;
277 if (bus_speed_changing) {
279 * Reconfigure DRAM refresh counter value for minimum
280 * temporary clock while changing divider.
281 * expected clock is 83Mhz : 7.8usec/(1/83Mhz) = 0x287
284 s5pv210_set_refresh(DMC1, 83000);
286 s5pv210_set_refresh(DMC1, 100000);
288 s5pv210_set_refresh(DMC0, 83000);
292 * APLL should be changed in this level
293 * APLL -> MPLL(for stable transition) -> APLL
294 * Some clock source's clock API are not prepared.
295 * Do not use clock API in below code.
299 * 1. Temporary Change divider for MFC and G3D
300 * SCLKA2M(200/1=200)->(200/4=50)Mhz
302 reg = __raw_readl(S5P_CLK_DIV2);
303 reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
304 reg |= (3 << S5P_CLKDIV2_G3D_SHIFT) |
305 (3 << S5P_CLKDIV2_MFC_SHIFT);
306 __raw_writel(reg, S5P_CLK_DIV2);
308 /* For MFC, G3D dividing */
310 reg = __raw_readl(S5P_CLKDIV_STAT0);
311 } while (reg & ((1 << 16) | (1 << 17)));
314 * 2. Change SCLKA2M(200Mhz)to SCLKMPLL in MFC_MUX, G3D MUX
315 * (200/4=50)->(667/4=166)Mhz
317 reg = __raw_readl(S5P_CLK_SRC2);
318 reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
319 reg |= (1 << S5P_CLKSRC2_G3D_SHIFT) |
320 (1 << S5P_CLKSRC2_MFC_SHIFT);
321 __raw_writel(reg, S5P_CLK_SRC2);
324 reg = __raw_readl(S5P_CLKMUX_STAT1);
325 } while (reg & ((1 << 7) | (1 << 3)));
328 * 3. DMC1 refresh count for 133Mhz if (index == L4) is
329 * true refresh counter is already programed in upper
332 if (!bus_speed_changing)
333 s5pv210_set_refresh(DMC1, 133000);
335 /* 4. SCLKAPLL -> SCLKMPLL */
336 reg = __raw_readl(S5P_CLK_SRC0);
337 reg &= ~(S5P_CLKSRC0_MUX200_MASK);
338 reg |= (0x1 << S5P_CLKSRC0_MUX200_SHIFT);
339 __raw_writel(reg, S5P_CLK_SRC0);
342 reg = __raw_readl(S5P_CLKMUX_STAT0);
343 } while (reg & (0x1 << 18));
348 reg = __raw_readl(S5P_CLK_DIV0);
350 reg &= ~(S5P_CLKDIV0_APLL_MASK | S5P_CLKDIV0_A2M_MASK |
351 S5P_CLKDIV0_HCLK200_MASK | S5P_CLKDIV0_PCLK100_MASK |
352 S5P_CLKDIV0_HCLK166_MASK | S5P_CLKDIV0_PCLK83_MASK |
353 S5P_CLKDIV0_HCLK133_MASK | S5P_CLKDIV0_PCLK66_MASK);
355 reg |= ((clkdiv_val[index][0] << S5P_CLKDIV0_APLL_SHIFT) |
356 (clkdiv_val[index][1] << S5P_CLKDIV0_A2M_SHIFT) |
357 (clkdiv_val[index][2] << S5P_CLKDIV0_HCLK200_SHIFT) |
358 (clkdiv_val[index][3] << S5P_CLKDIV0_PCLK100_SHIFT) |
359 (clkdiv_val[index][4] << S5P_CLKDIV0_HCLK166_SHIFT) |
360 (clkdiv_val[index][5] << S5P_CLKDIV0_PCLK83_SHIFT) |
361 (clkdiv_val[index][6] << S5P_CLKDIV0_HCLK133_SHIFT) |
362 (clkdiv_val[index][7] << S5P_CLKDIV0_PCLK66_SHIFT));
364 __raw_writel(reg, S5P_CLK_DIV0);
367 reg = __raw_readl(S5P_CLKDIV_STAT0);
368 } while (reg & 0xff);
370 /* ARM MCS value changed */
371 reg = __raw_readl(S5P_ARM_MCS_CON);
378 __raw_writel(reg, S5P_ARM_MCS_CON);
381 /* 5. Set Lock time = 30us*24Mhz = 0x2cf */
382 __raw_writel(0x2cf, S5P_APLL_LOCK);
386 * 6-1. Set PMS values
387 * 6-2. Wait untile the PLL is locked
390 __raw_writel(APLL_VAL_1000, S5P_APLL_CON);
392 __raw_writel(APLL_VAL_800, S5P_APLL_CON);
395 reg = __raw_readl(S5P_APLL_CON);
396 } while (!(reg & (0x1 << 29)));
399 * 7. Change souce clock from SCLKMPLL(667Mhz)
400 * to SCLKA2M(200Mhz) in MFC_MUX and G3D MUX
401 * (667/4=166)->(200/4=50)Mhz
403 reg = __raw_readl(S5P_CLK_SRC2);
404 reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
405 reg |= (0 << S5P_CLKSRC2_G3D_SHIFT) |
406 (0 << S5P_CLKSRC2_MFC_SHIFT);
407 __raw_writel(reg, S5P_CLK_SRC2);
410 reg = __raw_readl(S5P_CLKMUX_STAT1);
411 } while (reg & ((1 << 7) | (1 << 3)));
414 * 8. Change divider for MFC and G3D
415 * (200/4=50)->(200/1=200)Mhz
417 reg = __raw_readl(S5P_CLK_DIV2);
418 reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
419 reg |= (clkdiv_val[index][10] << S5P_CLKDIV2_G3D_SHIFT) |
420 (clkdiv_val[index][9] << S5P_CLKDIV2_MFC_SHIFT);
421 __raw_writel(reg, S5P_CLK_DIV2);
423 /* For MFC, G3D dividing */
425 reg = __raw_readl(S5P_CLKDIV_STAT0);
426 } while (reg & ((1 << 16) | (1 << 17)));
428 /* 9. Change MPLL to APLL in MSYS_MUX */
429 reg = __raw_readl(S5P_CLK_SRC0);
430 reg &= ~(S5P_CLKSRC0_MUX200_MASK);
431 reg |= (0x0 << S5P_CLKSRC0_MUX200_SHIFT);
432 __raw_writel(reg, S5P_CLK_SRC0);
435 reg = __raw_readl(S5P_CLKMUX_STAT0);
436 } while (reg & (0x1 << 18));
439 * 10. DMC1 refresh counter
440 * L4 : DMC1 = 100Mhz 7.8us/(1/100) = 0x30c
441 * Others : DMC1 = 200Mhz 7.8us/(1/200) = 0x618
443 if (!bus_speed_changing)
444 s5pv210_set_refresh(DMC1, 200000);
448 * L4 level need to change memory bus speed, hence onedram clock divier
449 * and memory refresh parameter should be changed
451 if (bus_speed_changing) {
452 reg = __raw_readl(S5P_CLK_DIV6);
453 reg &= ~S5P_CLKDIV6_ONEDRAM_MASK;
454 reg |= (clkdiv_val[index][8] << S5P_CLKDIV6_ONEDRAM_SHIFT);
455 __raw_writel(reg, S5P_CLK_DIV6);
458 reg = __raw_readl(S5P_CLKDIV_STAT1);
459 } while (reg & (1 << 15));
461 /* Reconfigure DRAM refresh counter value */
467 s5pv210_set_refresh(DMC0, 166000);
468 s5pv210_set_refresh(DMC1, 200000);
474 s5pv210_set_refresh(DMC0, 83000);
475 s5pv210_set_refresh(DMC1, 100000);
479 if (new_freq < old_freq) {
480 regulator_set_voltage(int_regulator,
481 int_volt, int_volt_max);
483 regulator_set_voltage(arm_regulator,
484 arm_volt, arm_volt_max);
487 printk(KERN_DEBUG "Perf changed[L%d]\n", index);
490 mutex_unlock(&set_freq_lock);
494 static int check_mem_type(void __iomem *dmc_reg)
498 val = __raw_readl(dmc_reg + 0x4);
499 val = (val & (0xf << 8));
504 static int s5pv210_cpu_init(struct cpufreq_policy *policy)
506 unsigned long mem_type;
509 policy->clk = clk_get(NULL, "armclk");
510 if (IS_ERR(policy->clk))
511 return PTR_ERR(policy->clk);
513 dmc0_clk = clk_get(NULL, "sclk_dmc0");
514 if (IS_ERR(dmc0_clk)) {
515 ret = PTR_ERR(dmc0_clk);
519 dmc1_clk = clk_get(NULL, "hclk_msys");
520 if (IS_ERR(dmc1_clk)) {
521 ret = PTR_ERR(dmc1_clk);
525 if (policy->cpu != 0) {
531 * check_mem_type : This driver only support LPDDR & LPDDR2.
532 * other memory type is not supported.
534 mem_type = check_mem_type(dmc_base[0]);
536 if ((mem_type != LPDDR) && (mem_type != LPDDR2)) {
537 printk(KERN_ERR "CPUFreq doesn't support this memory type\n");
542 /* Find current refresh counter and frequency each DMC */
543 s5pv210_dram_conf[0].refresh = (__raw_readl(dmc_base[0] + 0x30) * 1000);
544 s5pv210_dram_conf[0].freq = clk_get_rate(dmc0_clk);
546 s5pv210_dram_conf[1].refresh = (__raw_readl(dmc_base[1] + 0x30) * 1000);
547 s5pv210_dram_conf[1].freq = clk_get_rate(dmc1_clk);
549 policy->suspend_freq = SLEEP_FREQ;
550 return cpufreq_generic_init(policy, s5pv210_freq_table, 40000);
555 clk_put(policy->clk);
559 static int s5pv210_cpufreq_reboot_notifier_event(struct notifier_block *this,
560 unsigned long event, void *ptr)
564 ret = cpufreq_driver_target(cpufreq_cpu_get(0), SLEEP_FREQ, 0);
568 no_cpufreq_access = true;
572 static struct cpufreq_driver s5pv210_driver = {
573 .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
574 .verify = cpufreq_generic_frequency_table_verify,
575 .target_index = s5pv210_target,
576 .get = cpufreq_generic_get,
577 .init = s5pv210_cpu_init,
580 .suspend = cpufreq_generic_suspend,
581 .resume = cpufreq_generic_suspend, /* We need to set SLEEP FREQ again */
585 static struct notifier_block s5pv210_cpufreq_reboot_notifier = {
586 .notifier_call = s5pv210_cpufreq_reboot_notifier_event,
589 static int s5pv210_cpufreq_probe(struct platform_device *pdev)
591 struct device_node *np;
595 * HACK: This is a temporary workaround to get access to clock
596 * and DMC controller registers directly and remove static mappings
597 * and dependencies on platform headers. It is necessary to enable
598 * S5PV210 multi-platform support and will be removed together with
599 * this whole driver as soon as S5PV210 gets migrated to use
602 np = of_find_compatible_node(NULL, NULL, "samsung,s5pv210-clock");
604 pr_err("%s: failed to find clock controller DT node\n",
609 clk_base = of_iomap(np, 0);
611 pr_err("%s: failed to map clock registers\n", __func__);
615 for_each_compatible_node(np, NULL, "samsung,s5pv210-dmc") {
616 id = of_alias_get_id(np, "dmc");
617 if (id < 0 || id >= ARRAY_SIZE(dmc_base)) {
618 pr_err("%s: failed to get alias of dmc node '%s'\n",
623 dmc_base[id] = of_iomap(np, 0);
625 pr_err("%s: failed to map dmc%d registers\n",
631 for (id = 0; id < ARRAY_SIZE(dmc_base); ++id) {
633 pr_err("%s: failed to find dmc%d node\n", __func__, id);
638 arm_regulator = regulator_get(NULL, "vddarm");
639 if (IS_ERR(arm_regulator)) {
640 pr_err("failed to get regulator vddarm");
641 return PTR_ERR(arm_regulator);
644 int_regulator = regulator_get(NULL, "vddint");
645 if (IS_ERR(int_regulator)) {
646 pr_err("failed to get regulator vddint");
647 regulator_put(arm_regulator);
648 return PTR_ERR(int_regulator);
651 register_reboot_notifier(&s5pv210_cpufreq_reboot_notifier);
653 return cpufreq_register_driver(&s5pv210_driver);
656 static struct platform_driver s5pv210_cpufreq_platdrv = {
658 .name = "s5pv210-cpufreq",
660 .probe = s5pv210_cpufreq_probe,
662 module_platform_driver(s5pv210_cpufreq_platdrv);