target/linux/brcm2708/patches-4.4/0265-ARM-bcm2835-add-rpi-power-domain-driver.patch

   1 From a537e763c6c8d5516b6a66d053b10ce782db53df Mon Sep 17 00:00:00 2001
   2 From: Alexander Aring <alex.aring@gmail.com>
   3 Date: Wed, 16 Dec 2015 16:26:47 -0800
   4 Subject: [PATCH] ARM: bcm2835: add rpi power domain driver
   5
   6 This patch adds support for several power domains on Raspberry Pi,
   7 including USB (so it can be enabled even if the bootloader didn't do
   8 it), and graphics.
   9
  10 This patch is the combined work of Eric Anholt (who wrote USB support
  11 inside of the Raspberry Pi firmware driver, and wrote the non-USB
  12 domain support) and Alexander Aring (who separated the original USB
  13 work out from the firmware driver).
  14
  15 Signed-off-by: Alexander Aring <alex.aring@gmail.com>
  16 Signed-off-by: Eric Anholt <eric@anholt.net>
  17 Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
  18 Reviewed-by: Kevin Hilman <khilman@linaro.org>
  19 (cherry picked from commit a09cd356586d33f64cbe64ee4f5c1a7c4a6abee5)
  20 ---
  21  drivers/soc/Kconfig                           |   1 +
  22  drivers/soc/Makefile                          |   1 +
  23  drivers/soc/bcm/Kconfig                       |   9 +
  24  drivers/soc/bcm/Makefile                      |   1 +
  25  drivers/soc/bcm/raspberrypi-power.c           | 247 ++++++++++++++++++++++++++
  26  include/dt-bindings/power/raspberrypi-power.h |  41 +++++
  27  6 files changed, 300 insertions(+)
  28  create mode 100644 drivers/soc/bcm/Kconfig
  29  create mode 100644 drivers/soc/bcm/Makefile
  30  create mode 100644 drivers/soc/bcm/raspberrypi-power.c
  31  create mode 100644 include/dt-bindings/power/raspberrypi-power.h
  32
  33 --- a/drivers/soc/Kconfig
  34 +++ b/drivers/soc/Kconfig
  35 @@ -1,5 +1,6 @@
  36  menu "SOC (System On Chip) specific Drivers"
  37
  38 +source "drivers/soc/bcm/Kconfig"
  39  source "drivers/soc/brcmstb/Kconfig"
  40  source "drivers/soc/mediatek/Kconfig"
  41  source "drivers/soc/qcom/Kconfig"
  42 --- a/drivers/soc/Makefile
  43 +++ b/drivers/soc/Makefile
  44 @@ -2,6 +2,7 @@
  45  # Makefile for the Linux Kernel SOC specific device drivers.
  46  #
  47
  48 +obj-y                          += bcm/
  49  obj-$(CONFIG_SOC_BRCMSTB)      += brcmstb/
  50  obj-$(CONFIG_MACH_DOVE)                += dove/
  51  obj-$(CONFIG_ARCH_MEDIATEK)    += mediatek/
  52 --- /dev/null
  53 +++ b/drivers/soc/bcm/Kconfig
  54 @@ -0,0 +1,9 @@
  55 +config RASPBERRYPI_POWER
  56 +       bool "Raspberry Pi power domain driver"
  57 +       depends on ARCH_BCM2835 || COMPILE_TEST
  58 +       depends on RASPBERRYPI_FIRMWARE
  59 +       select PM_GENERIC_DOMAINS if PM
  60 +       select PM_GENERIC_DOMAINS_OF if PM
  61 +       help
  62 +         This enables support for the RPi power domains which can be enabled
  63 +         or disabled via the RPi firmware.
  64 --- /dev/null
  65 +++ b/drivers/soc/bcm/Makefile
  66 @@ -0,0 +1 @@
  67 +obj-$(CONFIG_RASPBERRYPI_POWER)        += raspberrypi-power.o
  68 --- /dev/null
  69 +++ b/drivers/soc/bcm/raspberrypi-power.c
  70 @@ -0,0 +1,247 @@
  71 +/* (C) 2015 Pengutronix, Alexander Aring <aar@pengutronix.de>
  72 + *
  73 + * This program is free software; you can redistribute it and/or modify
  74 + * it under the terms of the GNU General Public License version 2 as
  75 + * published by the Free Software Foundation.
  76 + *
  77 + * Authors:
  78 + * Alexander Aring <aar@pengutronix.de>
  79 + * Eric Anholt <eric@anholt.net>
  80 + */
  81 +
  82 +#include <linux/module.h>
  83 +#include <linux/of_platform.h>
  84 +#include <linux/platform_device.h>
  85 +#include <linux/pm_domain.h>
  86 +#include <dt-bindings/power/raspberrypi-power.h>
  87 +#include <soc/bcm2835/raspberrypi-firmware.h>
  88 +
  89 +/*
  90 + * Firmware indices for the old power domains interface.  Only a few
  91 + * of them were actually implemented.
  92 + */
  93 +#define RPI_OLD_POWER_DOMAIN_USB               3
  94 +#define RPI_OLD_POWER_DOMAIN_V3D               10
  95 +
  96 +struct rpi_power_domain {
  97 +       u32 domain;
  98 +       bool enabled;
  99 +       bool old_interface;
 100 +       struct generic_pm_domain base;
 101 +       struct rpi_firmware *fw;
 102 +};
 103 +
 104 +struct rpi_power_domains {
 105 +       bool has_new_interface;
 106 +       struct genpd_onecell_data xlate;
 107 +       struct rpi_firmware *fw;
 108 +       struct rpi_power_domain domains[RPI_POWER_DOMAIN_COUNT];
 109 +};
 110 +
 111 +/*
 112 + * Packet definition used by RPI_FIRMWARE_SET_POWER_STATE and
 113 + * RPI_FIRMWARE_SET_DOMAIN_STATE
 114 + */
 115 +struct rpi_power_domain_packet {
 116 +       u32 domain;
 117 +       u32 on;
 118 +} __packet;
 119 +
 120 +/*
 121 + * Asks the firmware to enable or disable power on a specific power
 122 + * domain.
 123 + */
 124 +static int rpi_firmware_set_power(struct rpi_power_domain *rpi_domain, bool on)
 125 +{
 126 +       struct rpi_power_domain_packet packet;
 127 +
 128 +       packet.domain = rpi_domain->domain;
 129 +       packet.on = on;
 130 +       return rpi_firmware_property(rpi_domain->fw,
 131 +                                    rpi_domain->old_interface ?
 132 +                                    RPI_FIRMWARE_SET_POWER_STATE :
 133 +                                    RPI_FIRMWARE_SET_DOMAIN_STATE,
 134 +                                    &packet, sizeof(packet));
 135 +}
 136 +
 137 +static int rpi_domain_off(struct generic_pm_domain *domain)
 138 +{
 139 +       struct rpi_power_domain *rpi_domain =
 140 +               container_of(domain, struct rpi_power_domain, base);
 141 +
 142 +       return rpi_firmware_set_power(rpi_domain, false);
 143 +}
 144 +
 145 +static int rpi_domain_on(struct generic_pm_domain *domain)
 146 +{
 147 +       struct rpi_power_domain *rpi_domain =
 148 +               container_of(domain, struct rpi_power_domain, base);
 149 +
 150 +       return rpi_firmware_set_power(rpi_domain, true);
 151 +}
 152 +
 153 +static void rpi_common_init_power_domain(struct rpi_power_domains *rpi_domains,
 154 +                                        int xlate_index, const char *name)
 155 +{
 156 +       struct rpi_power_domain *dom = &rpi_domains->domains[xlate_index];
 157 +
 158 +       dom->fw = rpi_domains->fw;
 159 +
 160 +       dom->base.name = name;
 161 +       dom->base.power_on = rpi_domain_on;
 162 +       dom->base.power_off = rpi_domain_off;
 163 +
 164 +       /*
 165 +        * Treat all power domains as off at boot.
 166 +        *
 167 +        * The firmware itself may be keeping some domains on, but
 168 +        * from Linux's perspective all we control is the refcounts
 169 +        * that we give to the firmware, and we can't ask the firmware
 170 +        * to turn off something that we haven't ourselves turned on.
 171 +        */
 172 +       pm_genpd_init(&dom->base, NULL, true);
 173 +
 174 +       rpi_domains->xlate.domains[xlate_index] = &dom->base;
 175 +}
 176 +
 177 +static void rpi_init_power_domain(struct rpi_power_domains *rpi_domains,
 178 +                                 int xlate_index, const char *name)
 179 +{
 180 +       struct rpi_power_domain *dom = &rpi_domains->domains[xlate_index];
 181 +
 182 +       if (!rpi_domains->has_new_interface)
 183 +               return;
 184 +
 185 +       /* The DT binding index is the firmware's domain index minus one. */
 186 +       dom->domain = xlate_index + 1;
 187 +
 188 +       rpi_common_init_power_domain(rpi_domains, xlate_index, name);
 189 +}
 190 +
 191 +static void rpi_init_old_power_domain(struct rpi_power_domains *rpi_domains,
 192 +                                     int xlate_index, int domain,
 193 +                                     const char *name)
 194 +{
 195 +       struct rpi_power_domain *dom = &rpi_domains->domains[xlate_index];
 196 +
 197 +       dom->old_interface = true;
 198 +       dom->domain = domain;
 199 +
 200 +       rpi_common_init_power_domain(rpi_domains, xlate_index, name);
 201 +}
 202 +
 203 +/*
 204 + * Detects whether the firmware supports the new power domains interface.
 205 + *
 206 + * The firmware doesn't actually return an error on an unknown tag,
 207 + * and just skips over it, so we do the detection by putting an
 208 + * unexpected value in the return field and checking if it was
 209 + * unchanged.
 210 + */
 211 +static bool
 212 +rpi_has_new_domain_support(struct rpi_power_domains *rpi_domains)
 213 +{
 214 +       struct rpi_power_domain_packet packet;
 215 +       int ret;
 216 +
 217 +       packet.domain = RPI_POWER_DOMAIN_ARM;
 218 +       packet.on = ~0;
 219 +
 220 +       ret = rpi_firmware_property(rpi_domains->fw,
 221 +                                   RPI_FIRMWARE_GET_DOMAIN_STATE,
 222 +                                   &packet, sizeof(packet));
 223 +
 224 +       return ret == 0 && packet.on != ~0;
 225 +}
 226 +
 227 +static int rpi_power_probe(struct platform_device *pdev)
 228 +{
 229 +       struct device_node *fw_np;
 230 +       struct device *dev = &pdev->dev;
 231 +       struct rpi_power_domains *rpi_domains;
 232 +
 233 +       rpi_domains = devm_kzalloc(dev, sizeof(*rpi_domains), GFP_KERNEL);
 234 +       if (!rpi_domains)
 235 +               return -ENOMEM;
 236 +
 237 +       rpi_domains->xlate.domains =
 238 +               devm_kzalloc(dev, sizeof(*rpi_domains->xlate.domains) *
 239 +                            RPI_POWER_DOMAIN_COUNT, GFP_KERNEL);
 240 +       if (!rpi_domains->xlate.domains)
 241 +               return -ENOMEM;
 242 +
 243 +       rpi_domains->xlate.num_domains = RPI_POWER_DOMAIN_COUNT;
 244 +
 245 +       fw_np = of_parse_phandle(pdev->dev.of_node, "firmware", 0);
 246 +       if (!fw_np) {
 247 +               dev_err(&pdev->dev, "no firmware node\n");
 248 +               return -ENODEV;
 249 +       }
 250 +
 251 +       rpi_domains->fw = rpi_firmware_get(fw_np);
 252 +       of_node_put(fw_np);
 253 +       if (!rpi_domains->fw)
 254 +               return -EPROBE_DEFER;
 255 +
 256 +       rpi_domains->has_new_interface =
 257 +               rpi_has_new_domain_support(rpi_domains);
 258 +
 259 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_I2C0, "I2C0");
 260 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_I2C1, "I2C1");
 261 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_I2C2, "I2C2");
 262 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_VIDEO_SCALER,
 263 +                             "VIDEO_SCALER");
 264 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_VPU1, "VPU1");
 265 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_HDMI, "HDMI");
 266 +
 267 +       /*
 268 +        * Use the old firmware interface for USB power, so that we
 269 +        * can turn it on even if the firmware hasn't been updated.
 270 +        */
 271 +       rpi_init_old_power_domain(rpi_domains, RPI_POWER_DOMAIN_USB,
 272 +                                 RPI_OLD_POWER_DOMAIN_USB, "USB");
 273 +
 274 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_VEC, "VEC");
 275 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_JPEG, "JPEG");
 276 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_H264, "H264");
 277 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_V3D, "V3D");
 278 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_ISP, "ISP");
 279 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_UNICAM0, "UNICAM0");
 280 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_UNICAM1, "UNICAM1");
 281 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CCP2RX, "CCP2RX");
 282 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CSI2, "CSI2");
 283 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CPI, "CPI");
 284 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_DSI0, "DSI0");
 285 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_DSI1, "DSI1");
 286 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_TRANSPOSER,
 287 +                             "TRANSPOSER");
 288 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CCP2TX, "CCP2TX");
 289 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_CDP, "CDP");
 290 +       rpi_init_power_domain(rpi_domains, RPI_POWER_DOMAIN_ARM, "ARM");
 291 +
 292 +       of_genpd_add_provider_onecell(dev->of_node, &rpi_domains->xlate);
 293 +
 294 +       platform_set_drvdata(pdev, rpi_domains);
 295 +
 296 +       return 0;
 297 +}
 298 +
 299 +static const struct of_device_id rpi_power_of_match[] = {
 300 +       { .compatible = "raspberrypi,bcm2835-power", },
 301 +       {},
 302 +};
 303 +MODULE_DEVICE_TABLE(of, rpi_power_of_match);
 304 +
 305 +static struct platform_driver rpi_power_driver = {
 306 +       .driver = {
 307 +               .name = "raspberrypi-power",
 308 +               .of_match_table = rpi_power_of_match,
 309 +       },
 310 +       .probe          = rpi_power_probe,
 311 +};
 312 +builtin_platform_driver(rpi_power_driver);
 313 +
 314 +MODULE_AUTHOR("Alexander Aring <aar@pengutronix.de>");
 315 +MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
 316 +MODULE_DESCRIPTION("Raspberry Pi power domain driver");
 317 +MODULE_LICENSE("GPL v2");
 318 --- /dev/null
 319 +++ b/include/dt-bindings/power/raspberrypi-power.h
 320 @@ -0,0 +1,41 @@
 321 +/*
 322 + *  Copyright © 2015 Broadcom
 323 + *
 324 + * This program is free software; you can redistribute it and/or modify
 325 + * it under the terms of the GNU General Public License version 2 as
 326 + * published by the Free Software Foundation.
 327 + */
 328 +
 329 +#ifndef _DT_BINDINGS_ARM_BCM2835_RPI_POWER_H
 330 +#define _DT_BINDINGS_ARM_BCM2835_RPI_POWER_H
 331 +
 332 +/* These power domain indices are the firmware interface's indices
 333 + * minus one.
 334 + */
 335 +#define RPI_POWER_DOMAIN_I2C0          0
 336 +#define RPI_POWER_DOMAIN_I2C1          1
 337 +#define RPI_POWER_DOMAIN_I2C2          2
 338 +#define RPI_POWER_DOMAIN_VIDEO_SCALER  3
 339 +#define RPI_POWER_DOMAIN_VPU1          4
 340 +#define RPI_POWER_DOMAIN_HDMI          5
 341 +#define RPI_POWER_DOMAIN_USB           6
 342 +#define RPI_POWER_DOMAIN_VEC           7
 343 +#define RPI_POWER_DOMAIN_JPEG          8
 344 +#define RPI_POWER_DOMAIN_H264          9
 345 +#define RPI_POWER_DOMAIN_V3D           10
 346 +#define RPI_POWER_DOMAIN_ISP           11
 347 +#define RPI_POWER_DOMAIN_UNICAM0       12
 348 +#define RPI_POWER_DOMAIN_UNICAM1       13
 349 +#define RPI_POWER_DOMAIN_CCP2RX                14
 350 +#define RPI_POWER_DOMAIN_CSI2          15
 351 +#define RPI_POWER_DOMAIN_CPI           16
 352 +#define RPI_POWER_DOMAIN_DSI0          17
 353 +#define RPI_POWER_DOMAIN_DSI1          18
 354 +#define RPI_POWER_DOMAIN_TRANSPOSER    19
 355 +#define RPI_POWER_DOMAIN_CCP2TX                20
 356 +#define RPI_POWER_DOMAIN_CDP           21
 357 +#define RPI_POWER_DOMAIN_ARM           22
 358 +
 359 +#define RPI_POWER_DOMAIN_COUNT         23
 360 +
 361 +#endif /* _DT_BINDINGS_ARM_BCM2835_RPI_POWER_H */