Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 | // SPDX-License-Identifier: GPL-2.0
//
// Exynos Generic power domain support.
//
// Copyright (c) 2012 Samsung Electronics Co., Ltd.
// http://www.samsung.com
//
// Implementation of Exynos specific power domain control which is used in
// conjunction with runtime-pm. Support for both device-tree and non-device-tree
// based power domain support is included.
#include <linux/io.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/pm_domain.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/sched.h>
#define MAX_CLK_PER_DOMAIN 4
struct exynos_pm_domain_config {
/* Value for LOCAL_PWR_CFG and STATUS fields for each domain */
u32 local_pwr_cfg;
};
/*
* Exynos specific wrapper around the generic power domain
*/
struct exynos_pm_domain {
void __iomem *base;
bool is_off;
struct generic_pm_domain pd;
struct clk *oscclk;
struct clk *clk[MAX_CLK_PER_DOMAIN];
struct clk *pclk[MAX_CLK_PER_DOMAIN];
struct clk *asb_clk[MAX_CLK_PER_DOMAIN];
u32 local_pwr_cfg;
};
static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on)
{
struct exynos_pm_domain *pd;
void __iomem *base;
u32 timeout, pwr;
char *op;
int i;
pd = container_of(domain, struct exynos_pm_domain, pd);
base = pd->base;
for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
if (IS_ERR(pd->asb_clk[i]))
break;
clk_prepare_enable(pd->asb_clk[i]);
}
/* Set oscclk before powering off a domain*/
if (!power_on) {
for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
if (IS_ERR(pd->clk[i]))
break;
pd->pclk[i] = clk_get_parent(pd->clk[i]);
if (clk_set_parent(pd->clk[i], pd->oscclk))
pr_err("%s: error setting oscclk as parent to clock %d\n",
domain->name, i);
}
}
pwr = power_on ? pd->local_pwr_cfg : 0;
writel_relaxed(pwr, base);
/* Wait max 1ms */
timeout = 10;
while ((readl_relaxed(base + 0x4) & pd->local_pwr_cfg) != pwr) {
if (!timeout) {
op = (power_on) ? "enable" : "disable";
pr_err("Power domain %s %s failed\n", domain->name, op);
return -ETIMEDOUT;
}
timeout--;
cpu_relax();
usleep_range(80, 100);
}
/* Restore clocks after powering on a domain*/
if (power_on) {
for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
if (IS_ERR(pd->clk[i]))
break;
if (IS_ERR(pd->pclk[i]))
continue; /* Skip on first power up */
if (clk_set_parent(pd->clk[i], pd->pclk[i]))
pr_err("%s: error setting parent to clock%d\n",
domain->name, i);
}
}
for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
if (IS_ERR(pd->asb_clk[i]))
break;
clk_disable_unprepare(pd->asb_clk[i]);
}
return 0;
}
static int exynos_pd_power_on(struct generic_pm_domain *domain)
{
return exynos_pd_power(domain, true);
}
static int exynos_pd_power_off(struct generic_pm_domain *domain)
{
return exynos_pd_power(domain, false);
}
static const struct exynos_pm_domain_config exynos4210_cfg __initconst = {
.local_pwr_cfg = 0x7,
};
static const struct exynos_pm_domain_config exynos5433_cfg __initconst = {
.local_pwr_cfg = 0xf,
};
static const struct of_device_id exynos_pm_domain_of_match[] __initconst = {
{
.compatible = "samsung,exynos4210-pd",
.data = &exynos4210_cfg,
}, {
.compatible = "samsung,exynos5433-pd",
.data = &exynos5433_cfg,
},
{ },
};
static __init const char *exynos_get_domain_name(struct device_node *node)
{
const char *name;
if (of_property_read_string(node, "label", &name) < 0)
name = kbasename(node->full_name);
return kstrdup_const(name, GFP_KERNEL);
}
static const char *soc_force_no_clk[] = {
"samsung,exynos5250-clock",
"samsung,exynos5420-clock",
"samsung,exynos5800-clock",
};
static __init int exynos4_pm_init_power_domain(void)
{
struct device_node *np;
const struct of_device_id *match;
for_each_matching_node_and_match(np, exynos_pm_domain_of_match, &match) {
const struct exynos_pm_domain_config *pm_domain_cfg;
struct exynos_pm_domain *pd;
int on, i;
pm_domain_cfg = match->data;
pd = kzalloc(sizeof(*pd), GFP_KERNEL);
if (!pd) {
of_node_put(np);
return -ENOMEM;
}
pd->pd.name = exynos_get_domain_name(np);
if (!pd->pd.name) {
kfree(pd);
of_node_put(np);
return -ENOMEM;
}
pd->base = of_iomap(np, 0);
if (!pd->base) {
pr_warn("%s: failed to map memory\n", __func__);
kfree_const(pd->pd.name);
kfree(pd);
continue;
}
pd->pd.power_off = exynos_pd_power_off;
pd->pd.power_on = exynos_pd_power_on;
pd->local_pwr_cfg = pm_domain_cfg->local_pwr_cfg;
for (i = 0; i < ARRAY_SIZE(soc_force_no_clk); i++)
if (of_find_compatible_node(NULL, NULL,
soc_force_no_clk[i]))
goto no_clk;
for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
char clk_name[8];
snprintf(clk_name, sizeof(clk_name), "asb%d", i);
pd->asb_clk[i] = of_clk_get_by_name(np, clk_name);
if (IS_ERR(pd->asb_clk[i]))
break;
}
pd->oscclk = of_clk_get_by_name(np, "oscclk");
if (IS_ERR(pd->oscclk))
goto no_clk;
for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) {
char clk_name[8];
snprintf(clk_name, sizeof(clk_name), "clk%d", i);
pd->clk[i] = of_clk_get_by_name(np, clk_name);
if (IS_ERR(pd->clk[i]))
break;
/*
* Skip setting parent on first power up.
* The parent at this time may not be useful at all.
*/
pd->pclk[i] = ERR_PTR(-EINVAL);
}
if (IS_ERR(pd->clk[0]))
clk_put(pd->oscclk);
no_clk:
on = readl_relaxed(pd->base + 0x4) & pd->local_pwr_cfg;
pm_genpd_init(&pd->pd, NULL, !on);
of_genpd_add_provider_simple(np, &pd->pd);
}
/* Assign the child power domains to their parents */
for_each_matching_node(np, exynos_pm_domain_of_match) {
struct of_phandle_args child, parent;
child.np = np;
child.args_count = 0;
if (of_parse_phandle_with_args(np, "power-domains",
"#power-domain-cells", 0,
&parent) != 0)
continue;
if (of_genpd_add_subdomain(&parent, &child))
pr_warn("%pOF failed to add subdomain: %pOF\n",
parent.np, child.np);
else
pr_info("%pOF has as child subdomain: %pOF.\n",
parent.np, child.np);
}
return 0;
}
core_initcall(exynos4_pm_init_power_domain);
|