2 * R-Car SYSC Power management support
4 * Copyright (C) 2014 Magnus Damm
5 * Copyright (C) 2015-2016 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 */
61 static void __iomem
*rcar_sysc_base
;
62 static DEFINE_SPINLOCK(rcar_sysc_lock
); /* SMP CPUs + I/O devices */
64 static int rcar_sysc_pwr_on_off(const struct rcar_sysc_ch
*sysc_ch
, bool on
)
66 unsigned int sr_bit
, reg_offs
;
70 sr_bit
= SYSCSR_PONENB
;
71 reg_offs
= PWRONCR_OFFS
;
73 sr_bit
= SYSCSR_POFFENB
;
74 reg_offs
= PWROFFCR_OFFS
;
77 /* Wait until SYSC is ready to accept a power request */
78 for (k
= 0; k
< SYSCSR_RETRIES
; k
++) {
79 if (ioread32(rcar_sysc_base
+ SYSCSR
) & BIT(sr_bit
))
81 udelay(SYSCSR_DELAY_US
);
84 if (k
== SYSCSR_RETRIES
)
87 /* Submit power shutoff or power resume request */
88 iowrite32(BIT(sysc_ch
->chan_bit
),
89 rcar_sysc_base
+ sysc_ch
->chan_offs
+ reg_offs
);
94 static int rcar_sysc_power(const struct rcar_sysc_ch
*sysc_ch
, bool on
)
96 unsigned int isr_mask
= BIT(sysc_ch
->isr_bit
);
97 unsigned int chan_mask
= BIT(sysc_ch
->chan_bit
);
103 spin_lock_irqsave(&rcar_sysc_lock
, flags
);
105 iowrite32(isr_mask
, rcar_sysc_base
+ SYSCISCR
);
107 /* Submit power shutoff or resume request until it was accepted */
108 for (k
= 0; k
< PWRER_RETRIES
; k
++) {
109 ret
= rcar_sysc_pwr_on_off(sysc_ch
, on
);
113 status
= ioread32(rcar_sysc_base
+
114 sysc_ch
->chan_offs
+ PWRER_OFFS
);
115 if (!(status
& chan_mask
))
118 udelay(PWRER_DELAY_US
);
121 if (k
== PWRER_RETRIES
) {
126 /* Wait until the power shutoff or resume request has completed * */
127 for (k
= 0; k
< SYSCISR_RETRIES
; k
++) {
128 if (ioread32(rcar_sysc_base
+ SYSCISR
) & isr_mask
)
130 udelay(SYSCISR_DELAY_US
);
133 if (k
== SYSCISR_RETRIES
)
136 iowrite32(isr_mask
, rcar_sysc_base
+ SYSCISCR
);
139 spin_unlock_irqrestore(&rcar_sysc_lock
, flags
);
141 pr_debug("sysc power %s domain %d: %08x -> %d\n", on
? "on" : "off",
142 sysc_ch
->isr_bit
, ioread32(rcar_sysc_base
+ SYSCISR
), ret
);
146 int rcar_sysc_power_down(const struct rcar_sysc_ch
*sysc_ch
)
148 return rcar_sysc_power(sysc_ch
, false);
151 int rcar_sysc_power_up(const struct rcar_sysc_ch
*sysc_ch
)
153 return rcar_sysc_power(sysc_ch
, true);
156 static bool rcar_sysc_power_is_off(const struct rcar_sysc_ch
*sysc_ch
)
160 st
= ioread32(rcar_sysc_base
+ sysc_ch
->chan_offs
+ PWRSR_OFFS
);
161 if (st
& BIT(sysc_ch
->chan_bit
))
167 struct rcar_sysc_pd
{
168 struct generic_pm_domain genpd
;
169 struct rcar_sysc_ch ch
;
174 static inline struct rcar_sysc_pd
*to_rcar_pd(struct generic_pm_domain
*d
)
176 return container_of(d
, struct rcar_sysc_pd
, genpd
);
179 static int rcar_sysc_pd_power_off(struct generic_pm_domain
*genpd
)
181 struct rcar_sysc_pd
*pd
= to_rcar_pd(genpd
);
183 pr_debug("%s: %s\n", __func__
, genpd
->name
);
185 if (pd
->flags
& PD_NO_CR
) {
186 pr_debug("%s: Cannot control %s\n", __func__
, genpd
->name
);
190 if (pd
->flags
& PD_BUSY
) {
191 pr_debug("%s: %s busy\n", __func__
, genpd
->name
);
195 return rcar_sysc_power_down(&pd
->ch
);
198 static int rcar_sysc_pd_power_on(struct generic_pm_domain
*genpd
)
200 struct rcar_sysc_pd
*pd
= to_rcar_pd(genpd
);
202 pr_debug("%s: %s\n", __func__
, genpd
->name
);
204 if (pd
->flags
& PD_NO_CR
) {
205 pr_debug("%s: Cannot control %s\n", __func__
, genpd
->name
);
209 return rcar_sysc_power_up(&pd
->ch
);
212 static bool has_cpg_mstp
;
214 static void __init
rcar_sysc_pd_setup(struct rcar_sysc_pd
*pd
)
216 struct generic_pm_domain
*genpd
= &pd
->genpd
;
217 const char *name
= pd
->genpd
.name
;
218 struct dev_power_governor
*gov
= &simple_qos_governor
;
220 if (pd
->flags
& PD_CPU
) {
222 * This domain contains a CPU core and therefore it should
223 * only be turned off if the CPU is not in use.
225 pr_debug("PM domain %s contains %s\n", name
, "CPU");
226 pd
->flags
|= PD_BUSY
;
227 gov
= &pm_domain_always_on_gov
;
228 } else if (pd
->flags
& PD_SCU
) {
230 * This domain contains an SCU and cache-controller, and
231 * therefore it should only be turned off if the CPU cores are
234 pr_debug("PM domain %s contains %s\n", name
, "SCU");
235 pd
->flags
|= PD_BUSY
;
236 gov
= &pm_domain_always_on_gov
;
237 } else if (pd
->flags
& PD_NO_CR
) {
239 * This domain cannot be turned off.
241 pd
->flags
|= PD_BUSY
;
242 gov
= &pm_domain_always_on_gov
;
245 if (!(pd
->flags
& (PD_CPU
| PD_SCU
))) {
246 /* Enable Clock Domain for I/O devices */
247 genpd
->flags
= GENPD_FLAG_PM_CLK
;
249 genpd
->attach_dev
= cpg_mstp_attach_dev
;
250 genpd
->detach_dev
= cpg_mstp_detach_dev
;
252 genpd
->attach_dev
= cpg_mssr_attach_dev
;
253 genpd
->detach_dev
= cpg_mssr_detach_dev
;
257 genpd
->power_off
= rcar_sysc_pd_power_off
;
258 genpd
->power_on
= rcar_sysc_pd_power_on
;
260 if (pd
->flags
& (PD_CPU
| PD_NO_CR
)) {
261 /* Skip CPUs (handled by SMP code) and areas without control */
262 pr_debug("%s: Not touching %s\n", __func__
, genpd
->name
);
266 if (!rcar_sysc_power_is_off(&pd
->ch
)) {
267 pr_debug("%s: %s is already powered\n", __func__
, genpd
->name
);
271 rcar_sysc_power_up(&pd
->ch
);
274 pm_genpd_init(genpd
, gov
, false);
277 static const struct of_device_id rcar_sysc_matches
[] = {
278 #ifdef CONFIG_ARCH_R8A7743
279 { .compatible
= "renesas,r8a7743-sysc", .data
= &r8a7743_sysc_info
},
281 #ifdef CONFIG_ARCH_R8A7745
282 { .compatible
= "renesas,r8a7745-sysc", .data
= &r8a7745_sysc_info
},
284 #ifdef CONFIG_ARCH_R8A7779
285 { .compatible
= "renesas,r8a7779-sysc", .data
= &r8a7779_sysc_info
},
287 #ifdef CONFIG_ARCH_R8A7790
288 { .compatible
= "renesas,r8a7790-sysc", .data
= &r8a7790_sysc_info
},
290 #ifdef CONFIG_ARCH_R8A7791
291 { .compatible
= "renesas,r8a7791-sysc", .data
= &r8a7791_sysc_info
},
293 #ifdef CONFIG_ARCH_R8A7792
294 { .compatible
= "renesas,r8a7792-sysc", .data
= &r8a7792_sysc_info
},
296 #ifdef CONFIG_ARCH_R8A7793
297 /* R-Car M2-N is identical to R-Car M2-W w.r.t. power domains. */
298 { .compatible
= "renesas,r8a7793-sysc", .data
= &r8a7791_sysc_info
},
300 #ifdef CONFIG_ARCH_R8A7794
301 { .compatible
= "renesas,r8a7794-sysc", .data
= &r8a7794_sysc_info
},
303 #ifdef CONFIG_ARCH_R8A7795
304 { .compatible
= "renesas,r8a7795-sysc", .data
= &r8a7795_sysc_info
},
306 #ifdef CONFIG_ARCH_R8A7796
307 { .compatible
= "renesas,r8a7796-sysc", .data
= &r8a7796_sysc_info
},
312 struct rcar_pm_domains
{
313 struct genpd_onecell_data onecell_data
;
314 struct generic_pm_domain
*domains
[RCAR_PD_ALWAYS_ON
+ 1];
317 static int __init
rcar_sysc_pd_init(void)
319 const struct rcar_sysc_info
*info
;
320 const struct of_device_id
*match
;
321 struct rcar_pm_domains
*domains
;
322 struct device_node
*np
;
323 u32 syscier
, syscimr
;
331 np
= of_find_matching_node_and_match(NULL
, rcar_sysc_matches
, &match
);
337 has_cpg_mstp
= of_find_compatible_node(NULL
, NULL
,
338 "renesas,cpg-mstp-clocks");
340 base
= of_iomap(np
, 0);
342 pr_warn("%s: Cannot map regs\n", np
->full_name
);
347 rcar_sysc_base
= base
;
349 domains
= kzalloc(sizeof(*domains
), GFP_KERNEL
);
355 domains
->onecell_data
.domains
= domains
->domains
;
356 domains
->onecell_data
.num_domains
= ARRAY_SIZE(domains
->domains
);
358 for (i
= 0, syscier
= 0; i
< info
->num_areas
; i
++)
359 syscier
|= BIT(info
->areas
[i
].isr_bit
);
362 * Mask all interrupt sources to prevent the CPU from receiving them.
363 * Make sure not to clear reserved bits that were set before.
365 syscimr
= ioread32(base
+ SYSCIMR
);
367 pr_debug("%s: syscimr = 0x%08x\n", np
->full_name
, syscimr
);
368 iowrite32(syscimr
, base
+ SYSCIMR
);
371 * SYSC needs all interrupt sources enabled to control power.
373 pr_debug("%s: syscier = 0x%08x\n", np
->full_name
, syscier
);
374 iowrite32(syscier
, base
+ SYSCIER
);
376 for (i
= 0; i
< info
->num_areas
; i
++) {
377 const struct rcar_sysc_area
*area
= &info
->areas
[i
];
378 struct rcar_sysc_pd
*pd
;
380 pd
= kzalloc(sizeof(*pd
) + strlen(area
->name
) + 1, GFP_KERNEL
);
386 strcpy(pd
->name
, area
->name
);
387 pd
->genpd
.name
= pd
->name
;
388 pd
->ch
.chan_offs
= area
->chan_offs
;
389 pd
->ch
.chan_bit
= area
->chan_bit
;
390 pd
->ch
.isr_bit
= area
->isr_bit
;
391 pd
->flags
= area
->flags
;
393 rcar_sysc_pd_setup(pd
);
394 if (area
->parent
>= 0)
395 pm_genpd_add_subdomain(domains
->domains
[area
->parent
],
398 domains
->domains
[area
->isr_bit
] = &pd
->genpd
;
401 error
= of_genpd_add_provider_onecell(np
, &domains
->onecell_data
);
407 early_initcall(rcar_sysc_pd_init
);
409 void __init
rcar_sysc_init(phys_addr_t base
, u32 syscier
)
413 if (!rcar_sysc_pd_init())
416 rcar_sysc_base
= ioremap_nocache(base
, PAGE_SIZE
);
419 * Mask all interrupt sources to prevent the CPU from receiving them.
420 * Make sure not to clear reserved bits that were set before.
422 syscimr
= ioread32(rcar_sysc_base
+ SYSCIMR
);
424 pr_debug("%s: syscimr = 0x%08x\n", __func__
, syscimr
);
425 iowrite32(syscimr
, rcar_sysc_base
+ SYSCIMR
);
428 * SYSC needs all interrupt sources enabled to control power.
430 pr_debug("%s: syscier = 0x%08x\n", __func__
, syscier
);
431 iowrite32(syscier
, rcar_sysc_base
+ SYSCIER
);