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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/err.h>
18 #include <linux/clk.h>
20 #include <linux/cpufreq.h>
22 #include <linux/of_address.h>
23 #include <linux/platform_device.h>
24 #include <linux/reboot.h>
25 #include <linux/regulator/consumer.h>
27 static void __iomem
*clk_base
;
28 static void __iomem
*dmc_base
[2];
30 #define S5P_CLKREG(x) (clk_base + (x))
32 #define S5P_APLL_LOCK S5P_CLKREG(0x00)
33 #define S5P_APLL_CON S5P_CLKREG(0x100)
34 #define S5P_CLK_SRC0 S5P_CLKREG(0x200)
35 #define S5P_CLK_SRC2 S5P_CLKREG(0x208)
36 #define S5P_CLK_DIV0 S5P_CLKREG(0x300)
37 #define S5P_CLK_DIV2 S5P_CLKREG(0x308)
38 #define S5P_CLK_DIV6 S5P_CLKREG(0x318)
39 #define S5P_CLKDIV_STAT0 S5P_CLKREG(0x1000)
40 #define S5P_CLKDIV_STAT1 S5P_CLKREG(0x1004)
41 #define S5P_CLKMUX_STAT0 S5P_CLKREG(0x1100)
42 #define S5P_CLKMUX_STAT1 S5P_CLKREG(0x1104)
44 #define S5P_ARM_MCS_CON S5P_CLKREG(0x6100)
47 #define S5P_CLKSRC0_MUX200_SHIFT (16)
48 #define S5P_CLKSRC0_MUX200_MASK (0x1 << S5P_CLKSRC0_MUX200_SHIFT)
49 #define S5P_CLKSRC0_MUX166_MASK (0x1<<20)
50 #define S5P_CLKSRC0_MUX133_MASK (0x1<<24)
53 #define S5P_CLKSRC2_G3D_SHIFT (0)
54 #define S5P_CLKSRC2_G3D_MASK (0x3 << S5P_CLKSRC2_G3D_SHIFT)
55 #define S5P_CLKSRC2_MFC_SHIFT (4)
56 #define S5P_CLKSRC2_MFC_MASK (0x3 << S5P_CLKSRC2_MFC_SHIFT)
59 #define S5P_CLKDIV0_APLL_SHIFT (0)
60 #define S5P_CLKDIV0_APLL_MASK (0x7 << S5P_CLKDIV0_APLL_SHIFT)
61 #define S5P_CLKDIV0_A2M_SHIFT (4)
62 #define S5P_CLKDIV0_A2M_MASK (0x7 << S5P_CLKDIV0_A2M_SHIFT)
63 #define S5P_CLKDIV0_HCLK200_SHIFT (8)
64 #define S5P_CLKDIV0_HCLK200_MASK (0x7 << S5P_CLKDIV0_HCLK200_SHIFT)
65 #define S5P_CLKDIV0_PCLK100_SHIFT (12)
66 #define S5P_CLKDIV0_PCLK100_MASK (0x7 << S5P_CLKDIV0_PCLK100_SHIFT)
67 #define S5P_CLKDIV0_HCLK166_SHIFT (16)
68 #define S5P_CLKDIV0_HCLK166_MASK (0xF << S5P_CLKDIV0_HCLK166_SHIFT)
69 #define S5P_CLKDIV0_PCLK83_SHIFT (20)
70 #define S5P_CLKDIV0_PCLK83_MASK (0x7 << S5P_CLKDIV0_PCLK83_SHIFT)
71 #define S5P_CLKDIV0_HCLK133_SHIFT (24)
72 #define S5P_CLKDIV0_HCLK133_MASK (0xF << S5P_CLKDIV0_HCLK133_SHIFT)
73 #define S5P_CLKDIV0_PCLK66_SHIFT (28)
74 #define S5P_CLKDIV0_PCLK66_MASK (0x7 << S5P_CLKDIV0_PCLK66_SHIFT)
77 #define S5P_CLKDIV2_G3D_SHIFT (0)
78 #define S5P_CLKDIV2_G3D_MASK (0xF << S5P_CLKDIV2_G3D_SHIFT)
79 #define S5P_CLKDIV2_MFC_SHIFT (4)
80 #define S5P_CLKDIV2_MFC_MASK (0xF << S5P_CLKDIV2_MFC_SHIFT)
83 #define S5P_CLKDIV6_ONEDRAM_SHIFT (28)
84 #define S5P_CLKDIV6_ONEDRAM_MASK (0xF << S5P_CLKDIV6_ONEDRAM_SHIFT)
86 static struct clk
*dmc0_clk
;
87 static struct clk
*dmc1_clk
;
88 static DEFINE_MUTEX(set_freq_lock
);
90 /* APLL M,P,S values for 1G/800Mhz */
91 #define APLL_VAL_1000 ((1 << 31) | (125 << 16) | (3 << 8) | 1)
92 #define APLL_VAL_800 ((1 << 31) | (100 << 16) | (3 << 8) | 1)
94 /* Use 800MHz when entering sleep mode */
95 #define SLEEP_FREQ (800 * 1000)
97 /* Tracks if cpu freqency can be updated anymore */
98 static bool no_cpufreq_access
;
101 * DRAM configurations to calculate refresh counter for changing
102 * frequency of memory.
105 unsigned long freq
; /* HZ */
106 unsigned long refresh
; /* DRAM refresh counter * 1000 */
109 /* DRAM configuration (DMC0 and DMC1) */
110 static struct dram_conf s5pv210_dram_conf
[2];
116 enum s5pv210_mem_type
{
122 enum s5pv210_dmc_port
{
127 static struct cpufreq_frequency_table s5pv210_freq_table
[] = {
133 {0, 0, CPUFREQ_TABLE_END
},
136 static struct regulator
*arm_regulator
;
137 static struct regulator
*int_regulator
;
139 struct s5pv210_dvs_conf
{
140 int arm_volt
; /* uV */
141 int int_volt
; /* uV */
144 static const int arm_volt_max
= 1350000;
145 static const int int_volt_max
= 1250000;
147 static struct s5pv210_dvs_conf dvs_conf
[] = {
170 static u32 clkdiv_val
[5][11] = {
172 * Clock divider value for following
173 * { APLL, A2M, HCLK_MSYS, PCLK_MSYS,
174 * HCLK_DSYS, PCLK_DSYS, HCLK_PSYS, PCLK_PSYS,
175 * ONEDRAM, MFC, G3D }
178 /* L0 : [1000/200/100][166/83][133/66][200/200] */
179 {0, 4, 4, 1, 3, 1, 4, 1, 3, 0, 0},
181 /* L1 : [800/200/100][166/83][133/66][200/200] */
182 {0, 3, 3, 1, 3, 1, 4, 1, 3, 0, 0},
184 /* L2 : [400/200/100][166/83][133/66][200/200] */
185 {1, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
187 /* L3 : [200/200/100][166/83][133/66][200/200] */
188 {3, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
190 /* L4 : [100/100/100][83/83][66/66][100/100] */
191 {7, 7, 0, 0, 7, 0, 9, 0, 7, 0, 0},
195 * This function set DRAM refresh counter
196 * accoriding to operating frequency of DRAM
197 * ch: DMC port number 0 or 1
198 * freq: Operating frequency of DRAM(KHz)
200 static void s5pv210_set_refresh(enum s5pv210_dmc_port ch
, unsigned long freq
)
202 unsigned long tmp
, tmp1
;
203 void __iomem
*reg
= NULL
;
206 reg
= (dmc_base
[0] + 0x30);
207 } else if (ch
== DMC1
) {
208 reg
= (dmc_base
[1] + 0x30);
210 pr_err("Cannot find DMC port\n");
214 /* Find current DRAM frequency */
215 tmp
= s5pv210_dram_conf
[ch
].freq
;
219 tmp1
= s5pv210_dram_conf
[ch
].refresh
;
223 writel_relaxed(tmp1
, reg
);
226 static int s5pv210_target(struct cpufreq_policy
*policy
, unsigned int index
)
229 unsigned int priv_index
;
230 unsigned int pll_changing
= 0;
231 unsigned int bus_speed_changing
= 0;
232 unsigned int old_freq
, new_freq
;
233 int arm_volt
, int_volt
;
236 mutex_lock(&set_freq_lock
);
238 if (no_cpufreq_access
) {
239 pr_err("Denied access to %s as it is disabled temporarily\n",
245 old_freq
= policy
->cur
;
246 new_freq
= s5pv210_freq_table
[index
].frequency
;
248 /* Finding current running level index */
249 priv_index
= cpufreq_table_find_index_h(policy
, old_freq
);
251 arm_volt
= dvs_conf
[index
].arm_volt
;
252 int_volt
= dvs_conf
[index
].int_volt
;
254 if (new_freq
> old_freq
) {
255 ret
= regulator_set_voltage(arm_regulator
,
256 arm_volt
, arm_volt_max
);
260 ret
= regulator_set_voltage(int_regulator
,
261 int_volt
, int_volt_max
);
266 /* Check if there need to change PLL */
267 if ((index
== L0
) || (priv_index
== L0
))
270 /* Check if there need to change System bus clock */
271 if ((index
== L4
) || (priv_index
== L4
))
272 bus_speed_changing
= 1;
274 if (bus_speed_changing
) {
276 * Reconfigure DRAM refresh counter value for minimum
277 * temporary clock while changing divider.
278 * expected clock is 83Mhz : 7.8usec/(1/83Mhz) = 0x287
281 s5pv210_set_refresh(DMC1
, 83000);
283 s5pv210_set_refresh(DMC1
, 100000);
285 s5pv210_set_refresh(DMC0
, 83000);
289 * APLL should be changed in this level
290 * APLL -> MPLL(for stable transition) -> APLL
291 * Some clock source's clock API are not prepared.
292 * Do not use clock API in below code.
296 * 1. Temporary Change divider for MFC and G3D
297 * SCLKA2M(200/1=200)->(200/4=50)Mhz
299 reg
= readl_relaxed(S5P_CLK_DIV2
);
300 reg
&= ~(S5P_CLKDIV2_G3D_MASK
| S5P_CLKDIV2_MFC_MASK
);
301 reg
|= (3 << S5P_CLKDIV2_G3D_SHIFT
) |
302 (3 << S5P_CLKDIV2_MFC_SHIFT
);
303 writel_relaxed(reg
, S5P_CLK_DIV2
);
305 /* For MFC, G3D dividing */
307 reg
= readl_relaxed(S5P_CLKDIV_STAT0
);
308 } while (reg
& ((1 << 16) | (1 << 17)));
311 * 2. Change SCLKA2M(200Mhz)to SCLKMPLL in MFC_MUX, G3D MUX
312 * (200/4=50)->(667/4=166)Mhz
314 reg
= readl_relaxed(S5P_CLK_SRC2
);
315 reg
&= ~(S5P_CLKSRC2_G3D_MASK
| S5P_CLKSRC2_MFC_MASK
);
316 reg
|= (1 << S5P_CLKSRC2_G3D_SHIFT
) |
317 (1 << S5P_CLKSRC2_MFC_SHIFT
);
318 writel_relaxed(reg
, S5P_CLK_SRC2
);
321 reg
= readl_relaxed(S5P_CLKMUX_STAT1
);
322 } while (reg
& ((1 << 7) | (1 << 3)));
325 * 3. DMC1 refresh count for 133Mhz if (index == L4) is
326 * true refresh counter is already programed in upper
329 if (!bus_speed_changing
)
330 s5pv210_set_refresh(DMC1
, 133000);
332 /* 4. SCLKAPLL -> SCLKMPLL */
333 reg
= readl_relaxed(S5P_CLK_SRC0
);
334 reg
&= ~(S5P_CLKSRC0_MUX200_MASK
);
335 reg
|= (0x1 << S5P_CLKSRC0_MUX200_SHIFT
);
336 writel_relaxed(reg
, S5P_CLK_SRC0
);
339 reg
= readl_relaxed(S5P_CLKMUX_STAT0
);
340 } while (reg
& (0x1 << 18));
345 reg
= readl_relaxed(S5P_CLK_DIV0
);
347 reg
&= ~(S5P_CLKDIV0_APLL_MASK
| S5P_CLKDIV0_A2M_MASK
|
348 S5P_CLKDIV0_HCLK200_MASK
| S5P_CLKDIV0_PCLK100_MASK
|
349 S5P_CLKDIV0_HCLK166_MASK
| S5P_CLKDIV0_PCLK83_MASK
|
350 S5P_CLKDIV0_HCLK133_MASK
| S5P_CLKDIV0_PCLK66_MASK
);
352 reg
|= ((clkdiv_val
[index
][0] << S5P_CLKDIV0_APLL_SHIFT
) |
353 (clkdiv_val
[index
][1] << S5P_CLKDIV0_A2M_SHIFT
) |
354 (clkdiv_val
[index
][2] << S5P_CLKDIV0_HCLK200_SHIFT
) |
355 (clkdiv_val
[index
][3] << S5P_CLKDIV0_PCLK100_SHIFT
) |
356 (clkdiv_val
[index
][4] << S5P_CLKDIV0_HCLK166_SHIFT
) |
357 (clkdiv_val
[index
][5] << S5P_CLKDIV0_PCLK83_SHIFT
) |
358 (clkdiv_val
[index
][6] << S5P_CLKDIV0_HCLK133_SHIFT
) |
359 (clkdiv_val
[index
][7] << S5P_CLKDIV0_PCLK66_SHIFT
));
361 writel_relaxed(reg
, S5P_CLK_DIV0
);
364 reg
= readl_relaxed(S5P_CLKDIV_STAT0
);
365 } while (reg
& 0xff);
367 /* ARM MCS value changed */
368 reg
= readl_relaxed(S5P_ARM_MCS_CON
);
375 writel_relaxed(reg
, S5P_ARM_MCS_CON
);
378 /* 5. Set Lock time = 30us*24Mhz = 0x2cf */
379 writel_relaxed(0x2cf, S5P_APLL_LOCK
);
383 * 6-1. Set PMS values
384 * 6-2. Wait untile the PLL is locked
387 writel_relaxed(APLL_VAL_1000
, S5P_APLL_CON
);
389 writel_relaxed(APLL_VAL_800
, S5P_APLL_CON
);
392 reg
= readl_relaxed(S5P_APLL_CON
);
393 } while (!(reg
& (0x1 << 29)));
396 * 7. Change souce clock from SCLKMPLL(667Mhz)
397 * to SCLKA2M(200Mhz) in MFC_MUX and G3D MUX
398 * (667/4=166)->(200/4=50)Mhz
400 reg
= readl_relaxed(S5P_CLK_SRC2
);
401 reg
&= ~(S5P_CLKSRC2_G3D_MASK
| S5P_CLKSRC2_MFC_MASK
);
402 reg
|= (0 << S5P_CLKSRC2_G3D_SHIFT
) |
403 (0 << S5P_CLKSRC2_MFC_SHIFT
);
404 writel_relaxed(reg
, S5P_CLK_SRC2
);
407 reg
= readl_relaxed(S5P_CLKMUX_STAT1
);
408 } while (reg
& ((1 << 7) | (1 << 3)));
411 * 8. Change divider for MFC and G3D
412 * (200/4=50)->(200/1=200)Mhz
414 reg
= readl_relaxed(S5P_CLK_DIV2
);
415 reg
&= ~(S5P_CLKDIV2_G3D_MASK
| S5P_CLKDIV2_MFC_MASK
);
416 reg
|= (clkdiv_val
[index
][10] << S5P_CLKDIV2_G3D_SHIFT
) |
417 (clkdiv_val
[index
][9] << S5P_CLKDIV2_MFC_SHIFT
);
418 writel_relaxed(reg
, S5P_CLK_DIV2
);
420 /* For MFC, G3D dividing */
422 reg
= readl_relaxed(S5P_CLKDIV_STAT0
);
423 } while (reg
& ((1 << 16) | (1 << 17)));
425 /* 9. Change MPLL to APLL in MSYS_MUX */
426 reg
= readl_relaxed(S5P_CLK_SRC0
);
427 reg
&= ~(S5P_CLKSRC0_MUX200_MASK
);
428 reg
|= (0x0 << S5P_CLKSRC0_MUX200_SHIFT
);
429 writel_relaxed(reg
, S5P_CLK_SRC0
);
432 reg
= readl_relaxed(S5P_CLKMUX_STAT0
);
433 } while (reg
& (0x1 << 18));
436 * 10. DMC1 refresh counter
437 * L4 : DMC1 = 100Mhz 7.8us/(1/100) = 0x30c
438 * Others : DMC1 = 200Mhz 7.8us/(1/200) = 0x618
440 if (!bus_speed_changing
)
441 s5pv210_set_refresh(DMC1
, 200000);
445 * L4 level need to change memory bus speed, hence onedram clock divier
446 * and memory refresh parameter should be changed
448 if (bus_speed_changing
) {
449 reg
= readl_relaxed(S5P_CLK_DIV6
);
450 reg
&= ~S5P_CLKDIV6_ONEDRAM_MASK
;
451 reg
|= (clkdiv_val
[index
][8] << S5P_CLKDIV6_ONEDRAM_SHIFT
);
452 writel_relaxed(reg
, S5P_CLK_DIV6
);
455 reg
= readl_relaxed(S5P_CLKDIV_STAT1
);
456 } while (reg
& (1 << 15));
458 /* Reconfigure DRAM refresh counter value */
464 s5pv210_set_refresh(DMC0
, 166000);
465 s5pv210_set_refresh(DMC1
, 200000);
471 s5pv210_set_refresh(DMC0
, 83000);
472 s5pv210_set_refresh(DMC1
, 100000);
476 if (new_freq
< old_freq
) {
477 regulator_set_voltage(int_regulator
,
478 int_volt
, int_volt_max
);
480 regulator_set_voltage(arm_regulator
,
481 arm_volt
, arm_volt_max
);
484 printk(KERN_DEBUG
"Perf changed[L%d]\n", index
);
487 mutex_unlock(&set_freq_lock
);
491 static int check_mem_type(void __iomem
*dmc_reg
)
495 val
= readl_relaxed(dmc_reg
+ 0x4);
496 val
= (val
& (0xf << 8));
501 static int s5pv210_cpu_init(struct cpufreq_policy
*policy
)
503 unsigned long mem_type
;
506 policy
->clk
= clk_get(NULL
, "armclk");
507 if (IS_ERR(policy
->clk
))
508 return PTR_ERR(policy
->clk
);
510 dmc0_clk
= clk_get(NULL
, "sclk_dmc0");
511 if (IS_ERR(dmc0_clk
)) {
512 ret
= PTR_ERR(dmc0_clk
);
516 dmc1_clk
= clk_get(NULL
, "hclk_msys");
517 if (IS_ERR(dmc1_clk
)) {
518 ret
= PTR_ERR(dmc1_clk
);
522 if (policy
->cpu
!= 0) {
528 * check_mem_type : This driver only support LPDDR & LPDDR2.
529 * other memory type is not supported.
531 mem_type
= check_mem_type(dmc_base
[0]);
533 if ((mem_type
!= LPDDR
) && (mem_type
!= LPDDR2
)) {
534 pr_err("CPUFreq doesn't support this memory type\n");
539 /* Find current refresh counter and frequency each DMC */
540 s5pv210_dram_conf
[0].refresh
= (readl_relaxed(dmc_base
[0] + 0x30) * 1000);
541 s5pv210_dram_conf
[0].freq
= clk_get_rate(dmc0_clk
);
543 s5pv210_dram_conf
[1].refresh
= (readl_relaxed(dmc_base
[1] + 0x30) * 1000);
544 s5pv210_dram_conf
[1].freq
= clk_get_rate(dmc1_clk
);
546 policy
->suspend_freq
= SLEEP_FREQ
;
547 return cpufreq_generic_init(policy
, s5pv210_freq_table
, 40000);
552 clk_put(policy
->clk
);
556 static int s5pv210_cpufreq_reboot_notifier_event(struct notifier_block
*this,
557 unsigned long event
, void *ptr
)
561 ret
= cpufreq_driver_target(cpufreq_cpu_get(0), SLEEP_FREQ
, 0);
565 no_cpufreq_access
= true;
569 static struct cpufreq_driver s5pv210_driver
= {
570 .flags
= CPUFREQ_STICKY
| CPUFREQ_NEED_INITIAL_FREQ_CHECK
,
571 .verify
= cpufreq_generic_frequency_table_verify
,
572 .target_index
= s5pv210_target
,
573 .get
= cpufreq_generic_get
,
574 .init
= s5pv210_cpu_init
,
576 .suspend
= cpufreq_generic_suspend
,
577 .resume
= cpufreq_generic_suspend
, /* We need to set SLEEP FREQ again */
580 static struct notifier_block s5pv210_cpufreq_reboot_notifier
= {
581 .notifier_call
= s5pv210_cpufreq_reboot_notifier_event
,
584 static int s5pv210_cpufreq_probe(struct platform_device
*pdev
)
586 struct device_node
*np
;
590 * HACK: This is a temporary workaround to get access to clock
591 * and DMC controller registers directly and remove static mappings
592 * and dependencies on platform headers. It is necessary to enable
593 * S5PV210 multi-platform support and will be removed together with
594 * this whole driver as soon as S5PV210 gets migrated to use
597 np
= of_find_compatible_node(NULL
, NULL
, "samsung,s5pv210-clock");
599 pr_err("%s: failed to find clock controller DT node\n",
604 clk_base
= of_iomap(np
, 0);
606 pr_err("%s: failed to map clock registers\n", __func__
);
610 for_each_compatible_node(np
, NULL
, "samsung,s5pv210-dmc") {
611 id
= of_alias_get_id(np
, "dmc");
612 if (id
< 0 || id
>= ARRAY_SIZE(dmc_base
)) {
613 pr_err("%s: failed to get alias of dmc node '%s'\n",
618 dmc_base
[id
] = of_iomap(np
, 0);
620 pr_err("%s: failed to map dmc%d registers\n",
626 for (id
= 0; id
< ARRAY_SIZE(dmc_base
); ++id
) {
628 pr_err("%s: failed to find dmc%d node\n", __func__
, id
);
633 arm_regulator
= regulator_get(NULL
, "vddarm");
634 if (IS_ERR(arm_regulator
)) {
635 pr_err("failed to get regulator vddarm\n");
636 return PTR_ERR(arm_regulator
);
639 int_regulator
= regulator_get(NULL
, "vddint");
640 if (IS_ERR(int_regulator
)) {
641 pr_err("failed to get regulator vddint\n");
642 regulator_put(arm_regulator
);
643 return PTR_ERR(int_regulator
);
646 register_reboot_notifier(&s5pv210_cpufreq_reboot_notifier
);
648 return cpufreq_register_driver(&s5pv210_driver
);
651 static struct platform_driver s5pv210_cpufreq_platdrv
= {
653 .name
= "s5pv210-cpufreq",
655 .probe
= s5pv210_cpufreq_probe
,
657 builtin_platform_driver(s5pv210_cpufreq_platdrv
);