2 * R-Car SYSC Power management support
4 * Copyright (C) 2014 Magnus Damm
5 * Copyright (C) 2015-2017 Glider bvba
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License. See the file "COPYING" in the main directory of this archive
12 #include <linux/clk/renesas.h>
13 #include <linux/delay.h>
14 #include <linux/err.h>
16 #include <linux/of_address.h>
17 #include <linux/pm_domain.h>
18 #include <linux/slab.h>
19 #include <linux/spinlock.h>
21 #include <linux/soc/renesas/rcar-sysc.h>
23 #include "rcar-sysc.h"
26 #define SYSCSR 0x00 /* SYSC Status Register */
27 #define SYSCISR 0x04 /* Interrupt Status Register */
28 #define SYSCISCR 0x08 /* Interrupt Status Clear Register */
29 #define SYSCIER 0x0c /* Interrupt Enable Register */
30 #define SYSCIMR 0x10 /* Interrupt Mask Register */
32 /* SYSC Status Register */
33 #define SYSCSR_PONENB 1 /* Ready for power resume requests */
34 #define SYSCSR_POFFENB 0 /* Ready for power shutoff requests */
37 * Power Control Register Offsets inside the register block for each domain
38 * Note: The "CR" registers for ARM cores exist on H1 only
39 * Use WFI to power off, CPG/APMU to resume ARM cores on R-Car Gen2
40 * Use PSCI on R-Car Gen3
42 #define PWRSR_OFFS 0x00 /* Power Status Register */
43 #define PWROFFCR_OFFS 0x04 /* Power Shutoff Control Register */
44 #define PWROFFSR_OFFS 0x08 /* Power Shutoff Status Register */
45 #define PWRONCR_OFFS 0x0c /* Power Resume Control Register */
46 #define PWRONSR_OFFS 0x10 /* Power Resume Status Register */
47 #define PWRER_OFFS 0x14 /* Power Shutoff/Resume Error */
50 #define SYSCSR_RETRIES 100
51 #define SYSCSR_DELAY_US 1
53 #define PWRER_RETRIES 100
54 #define PWRER_DELAY_US 1
56 #define SYSCISR_RETRIES 1000
57 #define SYSCISR_DELAY_US 1
59 #define RCAR_PD_ALWAYS_ON 32 /* Always-on power area */
67 static void __iomem
*rcar_sysc_base
;
68 static DEFINE_SPINLOCK(rcar_sysc_lock
); /* SMP CPUs + I/O devices */
70 static int rcar_sysc_pwr_on_off(const struct rcar_sysc_ch
*sysc_ch
, bool on
)
72 unsigned int sr_bit
, reg_offs
;
76 sr_bit
= SYSCSR_PONENB
;
77 reg_offs
= PWRONCR_OFFS
;
79 sr_bit
= SYSCSR_POFFENB
;
80 reg_offs
= PWROFFCR_OFFS
;
83 /* Wait until SYSC is ready to accept a power request */
84 for (k
= 0; k
< SYSCSR_RETRIES
; k
++) {
85 if (ioread32(rcar_sysc_base
+ SYSCSR
) & BIT(sr_bit
))
87 udelay(SYSCSR_DELAY_US
);
90 if (k
== SYSCSR_RETRIES
)
93 /* Submit power shutoff or power resume request */
94 iowrite32(BIT(sysc_ch
->chan_bit
),
95 rcar_sysc_base
+ sysc_ch
->chan_offs
+ reg_offs
);
100 static int rcar_sysc_power(const struct rcar_sysc_ch
*sysc_ch
, bool on
)
102 unsigned int isr_mask
= BIT(sysc_ch
->isr_bit
);
103 unsigned int chan_mask
= BIT(sysc_ch
->chan_bit
);
109 spin_lock_irqsave(&rcar_sysc_lock
, flags
);
111 iowrite32(isr_mask
, rcar_sysc_base
+ SYSCISCR
);
113 /* Submit power shutoff or resume request until it was accepted */
114 for (k
= 0; k
< PWRER_RETRIES
; k
++) {
115 ret
= rcar_sysc_pwr_on_off(sysc_ch
, on
);
119 status
= ioread32(rcar_sysc_base
+
120 sysc_ch
->chan_offs
+ PWRER_OFFS
);
121 if (!(status
& chan_mask
))
124 udelay(PWRER_DELAY_US
);
127 if (k
== PWRER_RETRIES
) {
132 /* Wait until the power shutoff or resume request has completed * */
133 for (k
= 0; k
< SYSCISR_RETRIES
; k
++) {
134 if (ioread32(rcar_sysc_base
+ SYSCISR
) & isr_mask
)
136 udelay(SYSCISR_DELAY_US
);
139 if (k
== SYSCISR_RETRIES
)
142 iowrite32(isr_mask
, rcar_sysc_base
+ SYSCISCR
);
145 spin_unlock_irqrestore(&rcar_sysc_lock
, flags
);
147 pr_debug("sysc power %s domain %d: %08x -> %d\n", on
? "on" : "off",
148 sysc_ch
->isr_bit
, ioread32(rcar_sysc_base
+ SYSCISR
), ret
);
152 static int rcar_sysc_power_down(const struct rcar_sysc_ch
*sysc_ch
)
154 return rcar_sysc_power(sysc_ch
, false);
157 static int rcar_sysc_power_up(const struct rcar_sysc_ch
*sysc_ch
)
159 return rcar_sysc_power(sysc_ch
, true);
162 static bool rcar_sysc_power_is_off(const struct rcar_sysc_ch
*sysc_ch
)
166 st
= ioread32(rcar_sysc_base
+ sysc_ch
->chan_offs
+ PWRSR_OFFS
);
167 if (st
& BIT(sysc_ch
->chan_bit
))
173 struct rcar_sysc_pd
{
174 struct generic_pm_domain genpd
;
175 struct rcar_sysc_ch ch
;
180 static inline struct rcar_sysc_pd
*to_rcar_pd(struct generic_pm_domain
*d
)
182 return container_of(d
, struct rcar_sysc_pd
, genpd
);
185 static int rcar_sysc_pd_power_off(struct generic_pm_domain
*genpd
)
187 struct rcar_sysc_pd
*pd
= to_rcar_pd(genpd
);
189 pr_debug("%s: %s\n", __func__
, genpd
->name
);
190 return rcar_sysc_power_down(&pd
->ch
);
193 static int rcar_sysc_pd_power_on(struct generic_pm_domain
*genpd
)
195 struct rcar_sysc_pd
*pd
= to_rcar_pd(genpd
);
197 pr_debug("%s: %s\n", __func__
, genpd
->name
);
198 return rcar_sysc_power_up(&pd
->ch
);
201 static bool has_cpg_mstp
;
203 static int __init
rcar_sysc_pd_setup(struct rcar_sysc_pd
*pd
)
205 struct generic_pm_domain
*genpd
= &pd
->genpd
;
206 const char *name
= pd
->genpd
.name
;
207 struct dev_power_governor
*gov
= &simple_qos_governor
;
210 if (pd
->flags
& PD_CPU
) {
212 * This domain contains a CPU core and therefore it should
213 * only be turned off if the CPU is not in use.
215 pr_debug("PM domain %s contains %s\n", name
, "CPU");
216 genpd
->flags
|= GENPD_FLAG_ALWAYS_ON
;
217 } else if (pd
->flags
& PD_SCU
) {
219 * This domain contains an SCU and cache-controller, and
220 * therefore it should only be turned off if the CPU cores are
223 pr_debug("PM domain %s contains %s\n", name
, "SCU");
224 genpd
->flags
|= GENPD_FLAG_ALWAYS_ON
;
225 } else if (pd
->flags
& PD_NO_CR
) {
227 * This domain cannot be turned off.
229 genpd
->flags
|= GENPD_FLAG_ALWAYS_ON
;
232 if (!(pd
->flags
& (PD_CPU
| PD_SCU
))) {
233 /* Enable Clock Domain for I/O devices */
234 genpd
->flags
|= GENPD_FLAG_PM_CLK
| GENPD_FLAG_ACTIVE_WAKEUP
;
236 genpd
->attach_dev
= cpg_mstp_attach_dev
;
237 genpd
->detach_dev
= cpg_mstp_detach_dev
;
239 genpd
->attach_dev
= cpg_mssr_attach_dev
;
240 genpd
->detach_dev
= cpg_mssr_detach_dev
;
244 genpd
->power_off
= rcar_sysc_pd_power_off
;
245 genpd
->power_on
= rcar_sysc_pd_power_on
;
247 if (pd
->flags
& (PD_CPU
| PD_NO_CR
)) {
248 /* Skip CPUs (handled by SMP code) and areas without control */
249 pr_debug("%s: Not touching %s\n", __func__
, genpd
->name
);
253 if (!rcar_sysc_power_is_off(&pd
->ch
)) {
254 pr_debug("%s: %s is already powered\n", __func__
, genpd
->name
);
258 rcar_sysc_power_up(&pd
->ch
);
261 error
= pm_genpd_init(genpd
, gov
, false);
263 pr_err("Failed to init PM domain %s: %d\n", name
, error
);
268 static const struct of_device_id rcar_sysc_matches
[] __initconst
= {
269 #ifdef CONFIG_SYSC_R8A7743
270 { .compatible
= "renesas,r8a7743-sysc", .data
= &r8a7743_sysc_info
},
272 #ifdef CONFIG_SYSC_R8A7745
273 { .compatible
= "renesas,r8a7745-sysc", .data
= &r8a7745_sysc_info
},
275 #ifdef CONFIG_SYSC_R8A77470
276 { .compatible
= "renesas,r8a77470-sysc", .data
= &r8a77470_sysc_info
},
278 #ifdef CONFIG_SYSC_R8A7779
279 { .compatible
= "renesas,r8a7779-sysc", .data
= &r8a7779_sysc_info
},
281 #ifdef CONFIG_SYSC_R8A7790
282 { .compatible
= "renesas,r8a7790-sysc", .data
= &r8a7790_sysc_info
},
284 #ifdef CONFIG_SYSC_R8A7791
285 { .compatible
= "renesas,r8a7791-sysc", .data
= &r8a7791_sysc_info
},
286 /* R-Car M2-N is identical to R-Car M2-W w.r.t. power domains. */
287 { .compatible
= "renesas,r8a7793-sysc", .data
= &r8a7791_sysc_info
},
289 #ifdef CONFIG_SYSC_R8A7792
290 { .compatible
= "renesas,r8a7792-sysc", .data
= &r8a7792_sysc_info
},
292 #ifdef CONFIG_SYSC_R8A7794
293 { .compatible
= "renesas,r8a7794-sysc", .data
= &r8a7794_sysc_info
},
295 #ifdef CONFIG_SYSC_R8A7795
296 { .compatible
= "renesas,r8a7795-sysc", .data
= &r8a7795_sysc_info
},
298 #ifdef CONFIG_SYSC_R8A7796
299 { .compatible
= "renesas,r8a7796-sysc", .data
= &r8a7796_sysc_info
},
301 #ifdef CONFIG_SYSC_R8A77965
302 { .compatible
= "renesas,r8a77965-sysc", .data
= &r8a77965_sysc_info
},
304 #ifdef CONFIG_SYSC_R8A77970
305 { .compatible
= "renesas,r8a77970-sysc", .data
= &r8a77970_sysc_info
},
307 #ifdef CONFIG_SYSC_R8A77980
308 { .compatible
= "renesas,r8a77980-sysc", .data
= &r8a77980_sysc_info
},
310 #ifdef CONFIG_SYSC_R8A77990
311 { .compatible
= "renesas,r8a77990-sysc", .data
= &r8a77990_sysc_info
},
313 #ifdef CONFIG_SYSC_R8A77995
314 { .compatible
= "renesas,r8a77995-sysc", .data
= &r8a77995_sysc_info
},
319 struct rcar_pm_domains
{
320 struct genpd_onecell_data onecell_data
;
321 struct generic_pm_domain
*domains
[RCAR_PD_ALWAYS_ON
+ 1];
324 static struct genpd_onecell_data
*rcar_sysc_onecell_data
;
326 static int __init
rcar_sysc_pd_init(void)
328 const struct rcar_sysc_info
*info
;
329 const struct of_device_id
*match
;
330 struct rcar_pm_domains
*domains
;
331 struct device_node
*np
;
332 u32 syscier
, syscimr
;
337 np
= of_find_matching_node_and_match(NULL
, rcar_sysc_matches
, &match
);
344 error
= info
->init();
349 has_cpg_mstp
= of_find_compatible_node(NULL
, NULL
,
350 "renesas,cpg-mstp-clocks");
352 base
= of_iomap(np
, 0);
354 pr_warn("%pOF: Cannot map regs\n", np
);
359 rcar_sysc_base
= base
;
361 domains
= kzalloc(sizeof(*domains
), GFP_KERNEL
);
367 domains
->onecell_data
.domains
= domains
->domains
;
368 domains
->onecell_data
.num_domains
= ARRAY_SIZE(domains
->domains
);
369 rcar_sysc_onecell_data
= &domains
->onecell_data
;
371 for (i
= 0, syscier
= 0; i
< info
->num_areas
; i
++)
372 syscier
|= BIT(info
->areas
[i
].isr_bit
);
375 * Mask all interrupt sources to prevent the CPU from receiving them.
376 * Make sure not to clear reserved bits that were set before.
378 syscimr
= ioread32(base
+ SYSCIMR
);
380 pr_debug("%pOF: syscimr = 0x%08x\n", np
, syscimr
);
381 iowrite32(syscimr
, base
+ SYSCIMR
);
384 * SYSC needs all interrupt sources enabled to control power.
386 pr_debug("%pOF: syscier = 0x%08x\n", np
, syscier
);
387 iowrite32(syscier
, base
+ SYSCIER
);
390 * First, create all PM domains
392 for (i
= 0; i
< info
->num_areas
; i
++) {
393 const struct rcar_sysc_area
*area
= &info
->areas
[i
];
394 struct rcar_sysc_pd
*pd
;
397 /* Skip NULLified area */
401 pd
= kzalloc(sizeof(*pd
) + strlen(area
->name
) + 1, GFP_KERNEL
);
407 strcpy(pd
->name
, area
->name
);
408 pd
->genpd
.name
= pd
->name
;
409 pd
->ch
.chan_offs
= area
->chan_offs
;
410 pd
->ch
.chan_bit
= area
->chan_bit
;
411 pd
->ch
.isr_bit
= area
->isr_bit
;
412 pd
->flags
= area
->flags
;
414 error
= rcar_sysc_pd_setup(pd
);
418 domains
->domains
[area
->isr_bit
] = &pd
->genpd
;
422 * Second, link all PM domains to their parents
424 for (i
= 0; i
< info
->num_areas
; i
++) {
425 const struct rcar_sysc_area
*area
= &info
->areas
[i
];
427 if (!area
->name
|| area
->parent
< 0)
430 error
= pm_genpd_add_subdomain(domains
->domains
[area
->parent
],
431 domains
->domains
[area
->isr_bit
]);
433 pr_warn("Failed to add PM subdomain %s to parent %u\n",
434 area
->name
, area
->parent
);
437 error
= of_genpd_add_provider_onecell(np
, &domains
->onecell_data
);
443 early_initcall(rcar_sysc_pd_init
);
445 void __init
rcar_sysc_nullify(struct rcar_sysc_area
*areas
,
446 unsigned int num_areas
, u8 id
)
450 for (i
= 0; i
< num_areas
; i
++)
451 if (areas
[i
].isr_bit
== id
) {
452 areas
[i
].name
= NULL
;
457 #ifdef CONFIG_ARCH_R8A7779
458 static int rcar_sysc_power_cpu(unsigned int idx
, bool on
)
460 struct generic_pm_domain
*genpd
;
461 struct rcar_sysc_pd
*pd
;
464 if (!rcar_sysc_onecell_data
)
467 for (i
= 0; i
< rcar_sysc_onecell_data
->num_domains
; i
++) {
468 genpd
= rcar_sysc_onecell_data
->domains
[i
];
472 pd
= to_rcar_pd(genpd
);
473 if (!(pd
->flags
& PD_CPU
) || pd
->ch
.chan_bit
!= idx
)
476 return on
? rcar_sysc_power_up(&pd
->ch
)
477 : rcar_sysc_power_down(&pd
->ch
);
483 int rcar_sysc_power_down_cpu(unsigned int cpu
)
485 return rcar_sysc_power_cpu(cpu
, false);
488 int rcar_sysc_power_up_cpu(unsigned int cpu
)
490 return rcar_sysc_power_cpu(cpu
, true);
492 #endif /* CONFIG_ARCH_R8A7779 */