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1// SPDX-License-Identifier: GPL-2.02/* (C) 2015 Pengutronix, Alexander Aring <aar@pengutronix.de>3 *4 * Authors:5 * Alexander Aring <aar@pengutronix.de>6 * Eric Anholt <eric@anholt.net>7 */8 9#include <linux/module.h>10#include <linux/of.h>11#include <linux/platform_device.h>12#include <linux/pm_domain.h>13#include <dt-bindings/power/raspberrypi-power.h>14#include <soc/bcm2835/raspberrypi-firmware.h>15 16/*17 * Firmware indices for the old power domains interface. Only a few18 * of them were actually implemented.19 */20#define RPI_OLD_POWER_DOMAIN_USB 321#define RPI_OLD_POWER_DOMAIN_V3D 1022 23struct rpi_power_domain {24 u32 domain;25 bool enabled;26 bool old_interface;27 struct generic_pm_domain base;28 struct rpi_firmware *fw;29};30 31struct rpi_power_domains {32 bool has_new_interface;33 struct genpd_onecell_data xlate;34 struct rpi_firmware *fw;35 struct rpi_power_domain domains[RPI_POWER_DOMAIN_COUNT];36};37 38/*39 * Packet definition used by RPI_FIRMWARE_SET_POWER_STATE and40 * RPI_FIRMWARE_SET_DOMAIN_STATE41 */42struct rpi_power_domain_packet {43 u32 domain;44 u32 state;45};46 47/*48 * Asks the firmware to enable or disable power on a specific power49 * domain.50 */51static int rpi_firmware_set_power(struct generic_pm_domain *domain, bool on)52{53 struct rpi_power_domain *rpi_domain =54 container_of(domain, struct rpi_power_domain, base);55 bool old_interface = rpi_domain->old_interface;56 struct rpi_power_domain_packet packet;57 int ret;58 59 packet.domain = rpi_domain->domain;60 packet.state = on;61 62 ret = rpi_firmware_property(rpi_domain->fw, old_interface ?63 RPI_FIRMWARE_SET_POWER_STATE :64 RPI_FIRMWARE_SET_DOMAIN_STATE,65 &packet, sizeof(packet));66 if (ret)67 dev_err(&domain->dev, "Failed to set %s to %u (%d)\n",68 old_interface ? "power" : "domain", on, ret);69 else70 dev_dbg(&domain->dev, "Set %s to %u\n",71 old_interface ? "power" : "domain", on);72 73 return ret;74}75 76static int rpi_domain_off(struct generic_pm_domain *domain)77{78 return rpi_firmware_set_power(domain, false);79}80 81static int rpi_domain_on(struct generic_pm_domain *domain)82{83 return rpi_firmware_set_power(domain, true);84}85 86static void rpi_common_init_power_domain(struct rpi_power_domains *rpi_domains,87 int xlate_index, const char *name)88{89 struct rpi_power_domain *dom = &rpi_domains->domains[xlate_index];90 91 dom->fw = rpi_domains->fw;92 93 dom->base.name = name;94 dom->base.flags = GENPD_FLAG_ACTIVE_WAKEUP;95 dom->base.power_on = rpi_domain_on;96 dom->base.power_off = rpi_domain_off;97 98 /*99 * Treat all power domains as off at boot.100 *101 * The firmware itself may be keeping some domains on, but102 * from Linux's perspective all we control is the refcounts103 * that we give to the firmware, and we can't ask the firmware104 * to turn off something that we haven't ourselves turned on.105 */106 pm_genpd_init(&dom->base, NULL, true);107 108 rpi_domains->xlate.domains[xlate_index] = &dom->base;109}110 111static void rpi_init_power_domain(struct rpi_power_domains *rpi_domains,112 int xlate_index, const char *name)113{114 struct rpi_power_domain *dom = &rpi_domains->domains[xlate_index];115 116 if (!rpi_domains->has_new_interface)117 return;118 119 /* The DT binding index is the firmware's domain index minus one. */120 dom->domain = xlate_index + 1;121 122 rpi_common_init_power_domain(rpi_domains, xlate_index, name);123}124 125static void rpi_init_old_power_domain(struct rpi_power_domains *rpi_domains,126 int xlate_index, int domain,127 const char *name)128{129 struct rpi_power_domain *dom = &rpi_domains->domains[xlate_index];130 131 dom->old_interface = true;132 dom->domain = domain;133 134 rpi_common_init_power_domain(rpi_domains, xlate_index, name);135}136 137/*138 * Detects whether the firmware supports the new power domains interface.139 *140 * The firmware doesn't actually return an error on an unknown tag,141 * and just skips over it, so we do the detection by putting an142 * unexpected value in the return field and checking if it was143 * unchanged.144 */145static bool146rpi_has_new_domain_support(struct rpi_power_domains *rpi_domains)147{148 struct rpi_power_domain_packet packet;149 int ret;150 151 packet.domain = RPI_POWER_DOMAIN_ARM;152 packet.state = ~0;153 154 ret = rpi_firmware_property(rpi_domains->fw,155 RPI_FIRMWARE_GET_DOMAIN_STATE,156 &packet, sizeof(packet));157 158 return ret == 0 && packet.state != ~0;159}160 161static int rpi_power_probe(struct platform_device *pdev)162{163 struct device_node *fw_np;164 struct device *dev = &pdev->dev;165 struct rpi_power_domains *rpi_domains;166 167 rpi_domains = devm_kzalloc(dev, sizeof(*rpi_domains), GFP_KERNEL);168 if (!rpi_domains)169 return -ENOMEM;170 171 rpi_domains->xlate.domains =172 devm_kcalloc(dev,173 RPI_POWER_DOMAIN_COUNT,174 sizeof(*rpi_domains->xlate.domains),175 GFP_KERNEL);176 if (!rpi_domains->xlate.domains)177 return -ENOMEM;178 179 rpi_domains->xlate.num_domains = RPI_POWER_DOMAIN_COUNT;180 181 fw_np = of_parse_phandle(pdev->dev.of_node, "firmware", 0);182 if (!fw_np) {183 dev_err(&pdev->dev, "no firmware node\n");184 return -ENODEV;185 }186 187 rpi_domains->fw = devm_rpi_firmware_get(&pdev->dev, fw_np);188 of_node_put(fw_np);189 if (!rpi_domains->fw)190 return -EPROBE_DEFER;191 192 rpi_domains->has_new_interface =193 rpi_has_new_domain_support(rpi_domains);194 195 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_I2C0, "I2C0");196 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_I2C1, "I2C1");197 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_I2C2, "I2C2");198 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_VIDEO_SCALER,199 "VIDEO_SCALER");200 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_VPU1, "VPU1");201 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_HDMI, "HDMI");202 203 /*204 * Use the old firmware interface for USB power, so that we205 * can turn it on even if the firmware hasn't been updated.206 */207 rpi_init_old_power_domain(rpi_domains, RPI_POWER_DOMAIN_USB,208 RPI_OLD_POWER_DOMAIN_USB, "USB");209 210 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_VEC, "VEC");211 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_JPEG, "JPEG");212 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_H264, "H264");213 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_V3D, "V3D");214 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_ISP, "ISP");215 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_UNICAM0, "UNICAM0");216 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_UNICAM1, "UNICAM1");217 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CCP2RX, "CCP2RX");218 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CSI2, "CSI2");219 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CPI, "CPI");220 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_DSI0, "DSI0");221 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_DSI1, "DSI1");222 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_TRANSPOSER,223 "TRANSPOSER");224 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CCP2TX, "CCP2TX");225 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CDP, "CDP");226 rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_ARM, "ARM");227 228 of_genpd_add_provider_onecell(dev->of_node, &rpi_domains->xlate);229 230 platform_set_drvdata(pdev, rpi_domains);231 232 return 0;233}234 235static const struct of_device_id rpi_power_of_match[] = {236 { .compatible = "raspberrypi,bcm2835-power", },237 {},238};239MODULE_DEVICE_TABLE(of, rpi_power_of_match);240 241static struct platform_driver rpi_power_driver = {242 .driver = {243 .name = "raspberrypi-power",244 .of_match_table = rpi_power_of_match,245 },246 .probe = rpi_power_probe,247};248builtin_platform_driver(rpi_power_driver);249 250MODULE_AUTHOR("Alexander Aring <aar@pengutronix.de>");251MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");252MODULE_DESCRIPTION("Raspberry Pi power domain driver");253