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 builtin_platform_driver(s5pv210_cpufreq_platdrv
);