1 // SPDX-License-Identifier: GPL-2.0
3 * rmobile power management support
5 * Copyright (C) 2012 Renesas Solutions Corp.
6 * Copyright (C) 2012 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
7 * Copyright (C) 2014 Glider bvba
10 * Copyright (C) 2011 Magnus Damm
12 #include <linux/clk/renesas.h>
13 #include <linux/console.h>
14 #include <linux/delay.h>
16 #include <linux/of_address.h>
17 #include <linux/of_platform.h>
18 #include <linux/platform_device.h>
20 #include <linux/pm_clock.h>
21 #include <linux/pm_domain.h>
22 #include <linux/slab.h>
27 #define SPDCR 0x08 /* SYS Power Down Control Register */
28 #define SWUCR 0x14 /* SYS Wakeup Control Register */
29 #define PSTR 0x80 /* Power Status Register */
31 #define PSTR_RETRIES 100
32 #define PSTR_DELAY_US 10
34 struct rmobile_pm_domain {
35 struct generic_pm_domain genpd;
36 struct dev_power_governor *gov;
39 unsigned int bit_shift;
43 struct rmobile_pm_domain *to_rmobile_pd(struct generic_pm_domain *d)
45 return container_of(d, struct rmobile_pm_domain, genpd);
48 static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
50 struct rmobile_pm_domain *rmobile_pd = to_rmobile_pd(genpd);
53 if (rmobile_pd->bit_shift == ~0)
56 mask = BIT(rmobile_pd->bit_shift);
57 if (rmobile_pd->suspend) {
58 int ret = rmobile_pd->suspend();
64 if (__raw_readl(rmobile_pd->base + PSTR) & mask) {
65 unsigned int retry_count;
66 __raw_writel(mask, rmobile_pd->base + SPDCR);
68 for (retry_count = PSTR_RETRIES; retry_count; retry_count--) {
69 if (!(__raw_readl(rmobile_pd->base + SPDCR) & mask))
75 pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n", genpd->name, mask,
76 __raw_readl(rmobile_pd->base + PSTR));
81 static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd)
84 unsigned int retry_count;
87 if (rmobile_pd->bit_shift == ~0)
90 mask = BIT(rmobile_pd->bit_shift);
91 if (__raw_readl(rmobile_pd->base + PSTR) & mask)
94 __raw_writel(mask, rmobile_pd->base + SWUCR);
96 for (retry_count = 2 * PSTR_RETRIES; retry_count; retry_count--) {
97 if (!(__raw_readl(rmobile_pd->base + SWUCR) & mask))
99 if (retry_count > PSTR_RETRIES)
100 udelay(PSTR_DELAY_US);
107 pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n",
108 rmobile_pd->genpd.name, mask,
109 __raw_readl(rmobile_pd->base + PSTR));
114 static int rmobile_pd_power_up(struct generic_pm_domain *genpd)
116 return __rmobile_pd_power_up(to_rmobile_pd(genpd));
119 static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
121 struct generic_pm_domain *genpd = &rmobile_pd->genpd;
122 struct dev_power_governor *gov = rmobile_pd->gov;
124 genpd->flags |= GENPD_FLAG_PM_CLK | GENPD_FLAG_ACTIVE_WAKEUP;
125 genpd->power_off = rmobile_pd_power_down;
126 genpd->power_on = rmobile_pd_power_up;
127 genpd->attach_dev = cpg_mstp_attach_dev;
128 genpd->detach_dev = cpg_mstp_detach_dev;
129 __rmobile_pd_power_up(rmobile_pd);
130 pm_genpd_init(genpd, gov ? : &simple_qos_governor, false);
133 static int rmobile_pd_suspend_console(void)
136 * Serial consoles make use of SCIF hardware located in this domain,
137 * hence keep the power domain on if "no_console_suspend" is set.
139 return console_suspend_enabled ? 0 : -EBUSY;
150 #define MAX_NUM_SPECIAL_PDS 16
152 static struct special_pd {
153 struct device_node *pd;
155 } special_pds[MAX_NUM_SPECIAL_PDS] __initdata;
157 static unsigned int num_special_pds __initdata;
159 static const struct of_device_id special_ids[] __initconst = {
160 { .compatible = "arm,coresight-etm3x", .data = (void *)PD_DEBUG },
161 { .compatible = "renesas,dbsc-r8a73a4", .data = (void *)PD_MEMCTL, },
162 { .compatible = "renesas,dbsc3-r8a7740", .data = (void *)PD_MEMCTL, },
163 { .compatible = "renesas,sbsc-sh73a0", .data = (void *)PD_MEMCTL, },
167 static void __init add_special_pd(struct device_node *np, enum pd_types type)
170 struct device_node *pd;
172 pd = of_parse_phandle(np, "power-domains", 0);
176 for (i = 0; i < num_special_pds; i++)
177 if (pd == special_pds[i].pd && type == special_pds[i].type) {
182 if (num_special_pds == ARRAY_SIZE(special_pds)) {
183 pr_warn("Too many special PM domains\n");
188 pr_debug("Special PM domain %pOFn type %d for %pOF\n", pd, type, np);
190 special_pds[num_special_pds].pd = pd;
191 special_pds[num_special_pds].type = type;
195 static void __init get_special_pds(void)
197 struct device_node *np;
198 const struct of_device_id *id;
200 /* PM domains containing CPUs */
201 for_each_of_cpu_node(np)
202 add_special_pd(np, PD_CPU);
204 /* PM domain containing console */
206 add_special_pd(of_stdout, PD_CONSOLE);
208 /* PM domains containing other special devices */
209 for_each_matching_node_and_match(np, special_ids, &id)
210 add_special_pd(np, (enum pd_types)id->data);
213 static void __init put_special_pds(void)
217 for (i = 0; i < num_special_pds; i++)
218 of_node_put(special_pds[i].pd);
221 static enum pd_types __init pd_type(const struct device_node *pd)
225 for (i = 0; i < num_special_pds; i++)
226 if (pd == special_pds[i].pd)
227 return special_pds[i].type;
232 static void __init rmobile_setup_pm_domain(struct device_node *np,
233 struct rmobile_pm_domain *pd)
235 const char *name = pd->genpd.name;
237 switch (pd_type(np)) {
240 * This domain contains the CPU core and therefore it should
241 * only be turned off if the CPU is not in use.
243 pr_debug("PM domain %s contains CPU\n", name);
244 pd->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
248 pr_debug("PM domain %s contains serial console\n", name);
249 pd->gov = &pm_domain_always_on_gov;
250 pd->suspend = rmobile_pd_suspend_console;
255 * This domain contains the Coresight-ETM hardware block and
256 * therefore it should only be turned off if the debug module
259 pr_debug("PM domain %s contains Coresight-ETM\n", name);
260 pd->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
265 * This domain contains a memory-controller and therefore it
266 * should only be turned off if memory is not in use.
268 pr_debug("PM domain %s contains MEMCTL\n", name);
269 pd->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
276 rmobile_init_pm_domain(pd);
279 static int __init rmobile_add_pm_domains(void __iomem *base,
280 struct device_node *parent,
281 struct generic_pm_domain *genpd_parent)
283 struct device_node *np;
285 for_each_child_of_node(parent, np) {
286 struct rmobile_pm_domain *pd;
289 if (of_property_read_u32(np, "reg", &idx)) {
290 /* always-on domain */
293 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
299 pd->genpd.name = np->name;
303 rmobile_setup_pm_domain(np, pd);
305 pm_genpd_add_subdomain(genpd_parent, &pd->genpd);
306 of_genpd_add_provider_simple(np, &pd->genpd);
308 rmobile_add_pm_domains(base, np, &pd->genpd);
313 static int __init rmobile_init_pm_domains(void)
315 struct device_node *np, *pmd;
316 bool scanned = false;
320 for_each_compatible_node(np, NULL, "renesas,sysc-rmobile") {
321 base = of_iomap(np, 0);
323 pr_warn("%pOF cannot map reg 0\n", np);
327 pmd = of_get_child_by_name(np, "pm-domains");
329 pr_warn("%pOF lacks pm-domains node\n", np);
334 /* Find PM domains containing special blocks */
339 ret = rmobile_add_pm_domains(base, pmd, NULL);
352 core_initcall(rmobile_init_pm_domains);