1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * OMAP4+ Power Management Routines 4 * 5 * Copyright (C) 2010-2013 Texas Instruments, Inc. 6 * Rajendra Nayak <rnayak@ti.com> 7 * Santosh Shilimkar <santosh.shilimkar@ti.com> 8 */ 9 10 #include <linux/pm.h> 11 #include <linux/suspend.h> 12 #include <linux/module.h> 13 #include <linux/list.h> 14 #include <linux/err.h> 15 #include <linux/slab.h> 16 #include <asm/system_misc.h> 17 18 #include "soc.h" 19 #include "common.h" 20 #include "clockdomain.h" 21 #include "powerdomain.h" 22 #include "pm.h" 23 24 u16 pm44xx_errata; 25 26 struct power_state { 27 struct powerdomain *pwrdm; 28 u32 next_state; 29 u32 next_logic_state; 30 #ifdef CONFIG_SUSPEND 31 u32 saved_state; 32 u32 saved_logic_state; 33 #endif 34 struct list_head node; 35 }; 36 37 /** 38 * struct static_dep_map - Static dependency map 39 * @from: from clockdomain 40 * @to: to clockdomain 41 */ 42 struct static_dep_map { 43 const char *from; 44 const char *to; 45 }; 46 47 static u32 cpu_suspend_state = PWRDM_POWER_OFF; 48 49 static LIST_HEAD(pwrst_list); 50 51 #ifdef CONFIG_SUSPEND 52 static int omap4_pm_suspend(void) 53 { 54 struct power_state *pwrst; 55 int state, ret = 0; 56 u32 cpu_id = smp_processor_id(); 57 58 /* Save current powerdomain state */ 59 list_for_each_entry(pwrst, &pwrst_list, node) { 60 pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm); 61 pwrst->saved_logic_state = pwrdm_read_logic_retst(pwrst->pwrdm); 62 } 63 64 /* Set targeted power domain states by suspend */ 65 list_for_each_entry(pwrst, &pwrst_list, node) { 66 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state); 67 pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->next_logic_state); 68 } 69 70 /* 71 * For MPUSS to hit power domain retention(CSWR or OSWR), 72 * CPU0 and CPU1 power domains need to be in OFF or DORMANT state, 73 * since CPU power domain CSWR is not supported by hardware 74 * Only master CPU follows suspend path. All other CPUs follow 75 * CPU hotplug path in system wide suspend. On OMAP4, CPU power 76 * domain CSWR is not supported by hardware. 77 * More details can be found in OMAP4430 TRM section 4.3.4.2. 78 */ 79 omap4_enter_lowpower(cpu_id, cpu_suspend_state, false); 80 81 /* Restore next powerdomain state */ 82 list_for_each_entry(pwrst, &pwrst_list, node) { 83 state = pwrdm_read_prev_pwrst(pwrst->pwrdm); 84 if (state > pwrst->next_state) { 85 pr_info("Powerdomain (%s) didn't enter target state %d\n", 86 pwrst->pwrdm->name, pwrst->next_state); 87 ret = -1; 88 } 89 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state); 90 pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state); 91 } 92 if (ret) { 93 pr_crit("Could not enter target state in pm_suspend\n"); 94 /* 95 * OMAP4 chip PM currently works only with certain (newer) 96 * versions of bootloaders. This is due to missing code in the 97 * kernel to properly reset and initialize some devices. 98 * Warn the user about the bootloader version being one of the 99 * possible causes. 100 * http://www.spinics.net/lists/arm-kernel/msg218641.html 101 */ 102 pr_debug("A possible cause could be an old bootloader - try u-boot >= v2012.07\n"); 103 } else { 104 pr_info("Successfully put all powerdomains to target state\n"); 105 } 106 107 return 0; 108 } 109 #else 110 #define omap4_pm_suspend NULL 111 #endif /* CONFIG_SUSPEND */ 112 113 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused) 114 { 115 struct power_state *pwrst; 116 117 if (!pwrdm->pwrsts) 118 return 0; 119 120 /* 121 * Skip CPU0 and CPU1 power domains. CPU1 is programmed 122 * through hotplug path and CPU0 explicitly programmed 123 * further down in the code path 124 */ 125 if (!strncmp(pwrdm->name, "cpu", 3)) { 126 if (IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE)) 127 cpu_suspend_state = PWRDM_POWER_RET; 128 return 0; 129 } 130 131 if (!strncmp(pwrdm->name, "core", 4) || 132 !strncmp(pwrdm->name, "l4per", 5)) 133 pwrdm_set_logic_retst(pwrdm, PWRDM_POWER_OFF); 134 135 pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC); 136 if (!pwrst) 137 return -ENOMEM; 138 139 pwrst->pwrdm = pwrdm; 140 pwrst->next_state = pwrdm_get_valid_lp_state(pwrdm, false, 141 PWRDM_POWER_RET); 142 pwrst->next_logic_state = pwrdm_get_valid_lp_state(pwrdm, true, 143 PWRDM_POWER_OFF); 144 145 list_add(&pwrst->node, &pwrst_list); 146 147 return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state); 148 } 149 150 /** 151 * omap_default_idle - OMAP4 default ilde routine.' 152 * 153 * Implements OMAP4 memory, IO ordering requirements which can't be addressed 154 * with default cpu_do_idle() hook. Used by all CPUs with !CONFIG_CPU_IDLE and 155 * by secondary CPU with CONFIG_CPU_IDLE. 156 */ 157 static void omap_default_idle(void) 158 { 159 omap_do_wfi(); 160 } 161 162 /* 163 * The dynamic dependency between MPUSS -> MEMIF and 164 * MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as 165 * expected. The hardware recommendation is to enable static 166 * dependencies for these to avoid system lock ups or random crashes. 167 * The L4 wakeup depedency is added to workaround the OCP sync hardware 168 * BUG with 32K synctimer which lead to incorrect timer value read 169 * from the 32K counter. The BUG applies for GPTIMER1 and WDT2 which 170 * are part of L4 wakeup clockdomain. 171 */ 172 static const struct static_dep_map omap4_static_dep_map[] = { 173 {.from = "mpuss_clkdm", .to = "l3_emif_clkdm"}, 174 {.from = "mpuss_clkdm", .to = "l3_1_clkdm"}, 175 {.from = "mpuss_clkdm", .to = "l3_2_clkdm"}, 176 {.from = "ducati_clkdm", .to = "l3_1_clkdm"}, 177 {.from = "ducati_clkdm", .to = "l3_2_clkdm"}, 178 {.from = NULL} /* TERMINATION */ 179 }; 180 181 static const struct static_dep_map omap5_dra7_static_dep_map[] = { 182 {.from = "mpu_clkdm", .to = "emif_clkdm"}, 183 {.from = NULL} /* TERMINATION */ 184 }; 185 186 /** 187 * omap4plus_init_static_deps() - Initialize a static dependency map 188 * @map: Mapping of clock domains 189 */ 190 static inline int omap4plus_init_static_deps(const struct static_dep_map *map) 191 { 192 int ret; 193 struct clockdomain *from, *to; 194 195 if (!map) 196 return 0; 197 198 while (map->from) { 199 from = clkdm_lookup(map->from); 200 to = clkdm_lookup(map->to); 201 if (!from || !to) { 202 pr_err("Failed lookup %s or %s for wakeup dependency\n", 203 map->from, map->to); 204 return -EINVAL; 205 } 206 ret = clkdm_add_wkdep(from, to); 207 if (ret) { 208 pr_err("Failed to add %s -> %s wakeup dependency(%d)\n", 209 map->from, map->to, ret); 210 return ret; 211 } 212 213 map++; 214 } 215 216 return 0; 217 } 218 219 /** 220 * omap4_pm_init_early - Does early initialization necessary for OMAP4+ devices 221 * 222 * Initializes basic stuff for power management functionality. 223 */ 224 int __init omap4_pm_init_early(void) 225 { 226 if (cpu_is_omap446x()) 227 pm44xx_errata |= PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD; 228 229 if (soc_is_omap54xx() || soc_is_dra7xx()) 230 pm44xx_errata |= PM_OMAP4_CPU_OSWR_DISABLE; 231 232 return 0; 233 } 234 235 /** 236 * omap4_pm_init - Init routine for OMAP4+ devices 237 * 238 * Initializes all powerdomain and clockdomain target states 239 * and all PRCM settings. 240 * Return: Returns the error code returned by called functions. 241 */ 242 int __init omap4_pm_init(void) 243 { 244 int ret = 0; 245 246 if (omap_rev() == OMAP4430_REV_ES1_0) { 247 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n"); 248 return -ENODEV; 249 } 250 251 pr_info("Power Management for TI OMAP4+ devices.\n"); 252 253 /* 254 * OMAP4 chip PM currently works only with certain (newer) 255 * versions of bootloaders. This is due to missing code in the 256 * kernel to properly reset and initialize some devices. 257 * http://www.spinics.net/lists/arm-kernel/msg218641.html 258 */ 259 if (cpu_is_omap44xx()) 260 pr_debug("OMAP4 PM: u-boot >= v2012.07 is required for full PM support\n"); 261 262 ret = pwrdm_for_each(pwrdms_setup, NULL); 263 if (ret) { 264 pr_err("Failed to setup powerdomains.\n"); 265 goto err2; 266 } 267 268 if (cpu_is_omap44xx()) 269 ret = omap4plus_init_static_deps(omap4_static_dep_map); 270 else if (soc_is_omap54xx() || soc_is_dra7xx()) 271 ret = omap4plus_init_static_deps(omap5_dra7_static_dep_map); 272 273 if (ret) { 274 pr_err("Failed to initialise static dependencies.\n"); 275 goto err2; 276 } 277 278 ret = omap4_mpuss_init(); 279 if (ret) { 280 pr_err("Failed to initialise OMAP4 MPUSS\n"); 281 goto err2; 282 } 283 284 (void) clkdm_for_each(omap_pm_clkdms_setup, NULL); 285 286 omap_common_suspend_init(omap4_pm_suspend); 287 288 /* Overwrite the default cpu_do_idle() */ 289 arm_pm_idle = omap_default_idle; 290 291 if (cpu_is_omap44xx() || soc_is_omap54xx()) 292 omap4_idle_init(); 293 294 err2: 295 return ret; 296 } 297