root/drivers/firmware/imx/scu-pd.c

DEFINITIONS

1. to_imx_sc_pd
2. imx_sc_pd_power
3. imx_sc_pd_power_on
4. imx_sc_pd_power_off
5. imx_scu_pd_xlate
6. imx_scu_add_pm_domain
7. imx_scu_init_pm_domains
8. imx_sc_pd_probe

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2016 Freescale Semiconductor, Inc.
   4  * Copyright 2017-2018 NXP
   5  *      Dong Aisheng <aisheng.dong@nxp.com>
   6  *
   7  * Implementation of the SCU based Power Domains
   8  *
   9  * NOTE: a better implementation suggested by Ulf Hansson is using a
  10  * single global power domain and implement the ->attach|detach_dev()
  11  * callback for the genpd and use the regular of_genpd_add_provider_simple().
  12  * From within the ->attach_dev(), we could get the OF node for
  13  * the device that is being attached and then parse the power-domain
  14  * cell containing the "resource id" and store that in the per device
  15  * struct generic_pm_domain_data (we have void pointer there for
  16  * storing these kind of things).
  17  *
  18  * Additionally, we need to implement the ->stop() and ->start()
  19  * callbacks of genpd, which is where you "power on/off" devices,
  20  * rather than using the above ->power_on|off() callbacks.
  21  *
  22  * However, there're two known issues:
  23  * 1. The ->attach_dev() of power domain infrastructure still does
  24  *    not support multi domains case as the struct device *dev passed
  25  *    in is a virtual PD device, it does not help for parsing the real
  26  *    device resource id from device tree, so it's unware of which
  27  *    real sub power domain of device should be attached.
  28  *
  29  *    The framework needs some proper extension to support multi power
  30  *    domain cases.
  31  *
  32  * 2. It also breaks most of current drivers as the driver probe sequence
  33  *    behavior changed if removing ->power_on|off() callback and use
  34  *    ->start() and ->stop() instead. genpd_dev_pm_attach will only power
  35  *    up the domain and attach device, but will not call .start() which
  36  *    relies on device runtime pm. That means the device power is still
  37  *    not up before running driver probe function. For SCU enabled
  38  *    platforms, all device drivers accessing registers/clock without power
  39  *    domain enabled will trigger a HW access error. That means we need fix
  40  *    most drivers probe sequence with proper runtime pm.
  41  *
  42  * In summary, we need fix above two issue before being able to switch to
  43  * the "single global power domain" way.
  44  *
  45  */
  46 
  47 #include <dt-bindings/firmware/imx/rsrc.h>
  48 #include <linux/firmware/imx/sci.h>
  49 #include <linux/io.h>
  50 #include <linux/module.h>
  51 #include <linux/of.h>
  52 #include <linux/of_address.h>
  53 #include <linux/of_platform.h>
  54 #include <linux/platform_device.h>
  55 #include <linux/pm.h>
  56 #include <linux/pm_domain.h>
  57 #include <linux/slab.h>
  58 
  59 /* SCU Power Mode Protocol definition */
  60 struct imx_sc_msg_req_set_resource_power_mode {
  61         struct imx_sc_rpc_msg hdr;
  62         u16 resource;
  63         u8 mode;
  64 } __packed __aligned(4);
  65 
  66 #define IMX_SCU_PD_NAME_SIZE 20
  67 struct imx_sc_pm_domain {
  68         struct generic_pm_domain pd;
  69         char name[IMX_SCU_PD_NAME_SIZE];
  70         u32 rsrc;
  71 };
  72 
  73 struct imx_sc_pd_range {
  74         char *name;
  75         u32 rsrc;
  76         u8 num;
  77 
  78         /* add domain index */
  79         bool postfix;
  80         u8 start_from;
  81 };
  82 
  83 struct imx_sc_pd_soc {
  84         const struct imx_sc_pd_range *pd_ranges;
  85         u8 num_ranges;
  86 };
  87 
  88 static const struct imx_sc_pd_range imx8qxp_scu_pd_ranges[] = {
  89         /* LSIO SS */
  90         { "pwm", IMX_SC_R_PWM_0, 8, true, 0 },
  91         { "gpio", IMX_SC_R_GPIO_0, 8, true, 0 },
  92         { "gpt", IMX_SC_R_GPT_0, 5, true, 0 },
  93         { "kpp", IMX_SC_R_KPP, 1, false, 0 },
  94         { "fspi", IMX_SC_R_FSPI_0, 2, true, 0 },
  95         { "mu_a", IMX_SC_R_MU_0A, 14, true, 0 },
  96         { "mu_b", IMX_SC_R_MU_13B, 1, true, 13 },
  97 
  98         /* CONN SS */
  99         { "usb", IMX_SC_R_USB_0, 2, true, 0 },
 100         { "usb0phy", IMX_SC_R_USB_0_PHY, 1, false, 0 },
 101         { "usb2", IMX_SC_R_USB_2, 1, false, 0 },
 102         { "usb2phy", IMX_SC_R_USB_2_PHY, 1, false, 0 },
 103         { "sdhc", IMX_SC_R_SDHC_0, 3, true, 0 },
 104         { "enet", IMX_SC_R_ENET_0, 2, true, 0 },
 105         { "nand", IMX_SC_R_NAND, 1, false, 0 },
 106         { "mlb", IMX_SC_R_MLB_0, 1, true, 0 },
 107 
 108         /* AUDIO SS */
 109         { "audio-pll0", IMX_SC_R_AUDIO_PLL_0, 1, false, 0 },
 110         { "audio-pll1", IMX_SC_R_AUDIO_PLL_1, 1, false, 0 },
 111         { "audio-clk-0", IMX_SC_R_AUDIO_CLK_0, 1, false, 0 },
 112         { "dma0-ch", IMX_SC_R_DMA_0_CH0, 16, true, 0 },
 113         { "dma1-ch", IMX_SC_R_DMA_1_CH0, 16, true, 0 },
 114         { "dma2-ch", IMX_SC_R_DMA_2_CH0, 5, true, 0 },
 115         { "asrc0", IMX_SC_R_ASRC_0, 1, false, 0 },
 116         { "asrc1", IMX_SC_R_ASRC_1, 1, false, 0 },
 117         { "esai0", IMX_SC_R_ESAI_0, 1, false, 0 },
 118         { "spdif0", IMX_SC_R_SPDIF_0, 1, false, 0 },
 119         { "sai", IMX_SC_R_SAI_0, 3, true, 0 },
 120         { "amix", IMX_SC_R_AMIX, 1, false, 0 },
 121         { "mqs0", IMX_SC_R_MQS_0, 1, false, 0 },
 122         { "dsp", IMX_SC_R_DSP, 1, false, 0 },
 123         { "dsp-ram", IMX_SC_R_DSP_RAM, 1, false, 0 },
 124 
 125         /* DMA SS */
 126         { "can", IMX_SC_R_CAN_0, 3, true, 0 },
 127         { "ftm", IMX_SC_R_FTM_0, 2, true, 0 },
 128         { "lpi2c", IMX_SC_R_I2C_0, 4, true, 0 },
 129         { "adc", IMX_SC_R_ADC_0, 1, true, 0 },
 130         { "lcd", IMX_SC_R_LCD_0, 1, true, 0 },
 131         { "lcd0-pwm", IMX_SC_R_LCD_0_PWM_0, 1, true, 0 },
 132         { "lpuart", IMX_SC_R_UART_0, 4, true, 0 },
 133         { "lpspi", IMX_SC_R_SPI_0, 4, true, 0 },
 134         { "irqstr_dsp", IMX_SC_R_IRQSTR_DSP, 1, false, 0 },
 135 
 136         /* VPU SS */
 137         { "vpu", IMX_SC_R_VPU, 1, false, 0 },
 138         { "vpu-pid", IMX_SC_R_VPU_PID0, 8, true, 0 },
 139         { "vpu-dec0", IMX_SC_R_VPU_DEC_0, 1, false, 0 },
 140         { "vpu-enc0", IMX_SC_R_VPU_ENC_0, 1, false, 0 },
 141 
 142         /* GPU SS */
 143         { "gpu0-pid", IMX_SC_R_GPU_0_PID0, 4, true, 0 },
 144 
 145         /* HSIO SS */
 146         { "pcie-b", IMX_SC_R_PCIE_B, 1, false, 0 },
 147         { "serdes-1", IMX_SC_R_SERDES_1, 1, false, 0 },
 148         { "hsio-gpio", IMX_SC_R_HSIO_GPIO, 1, false, 0 },
 149 
 150         /* MIPI SS */
 151         { "mipi0", IMX_SC_R_MIPI_0, 1, false, 0 },
 152         { "mipi0-pwm0", IMX_SC_R_MIPI_0_PWM_0, 1, false, 0 },
 153         { "mipi0-i2c", IMX_SC_R_MIPI_0_I2C_0, 2, true, 0 },
 154 
 155         /* LVDS SS */
 156         { "lvds0", IMX_SC_R_LVDS_0, 1, false, 0 },
 157 
 158         /* DC SS */
 159         { "dc0", IMX_SC_R_DC_0, 1, false, 0 },
 160         { "dc0-pll", IMX_SC_R_DC_0_PLL_0, 2, true, 0 },
 161 };
 162 
 163 static const struct imx_sc_pd_soc imx8qxp_scu_pd = {
 164         .pd_ranges = imx8qxp_scu_pd_ranges,
 165         .num_ranges = ARRAY_SIZE(imx8qxp_scu_pd_ranges),
 166 };
 167 
 168 static struct imx_sc_ipc *pm_ipc_handle;
 169 
 170 static inline struct imx_sc_pm_domain *
 171 to_imx_sc_pd(struct generic_pm_domain *genpd)
 172 {
 173         return container_of(genpd, struct imx_sc_pm_domain, pd);
 174 }
 175 
 176 static int imx_sc_pd_power(struct generic_pm_domain *domain, bool power_on)
 177 {
 178         struct imx_sc_msg_req_set_resource_power_mode msg;
 179         struct imx_sc_rpc_msg *hdr = &msg.hdr;
 180         struct imx_sc_pm_domain *pd;
 181         int ret;
 182 
 183         pd = to_imx_sc_pd(domain);
 184 
 185         hdr->ver = IMX_SC_RPC_VERSION;
 186         hdr->svc = IMX_SC_RPC_SVC_PM;
 187         hdr->func = IMX_SC_PM_FUNC_SET_RESOURCE_POWER_MODE;
 188         hdr->size = 2;
 189 
 190         msg.resource = pd->rsrc;
 191         msg.mode = power_on ? IMX_SC_PM_PW_MODE_ON : IMX_SC_PM_PW_MODE_LP;
 192 
 193         ret = imx_scu_call_rpc(pm_ipc_handle, &msg, true);
 194         if (ret)
 195                 dev_err(&domain->dev, "failed to power %s resource %d ret %d\n",
 196                         power_on ? "up" : "off", pd->rsrc, ret);
 197 
 198         return ret;
 199 }
 200 
 201 static int imx_sc_pd_power_on(struct generic_pm_domain *domain)
 202 {
 203         return imx_sc_pd_power(domain, true);
 204 }
 205 
 206 static int imx_sc_pd_power_off(struct generic_pm_domain *domain)
 207 {
 208         return imx_sc_pd_power(domain, false);
 209 }
 210 
 211 static struct generic_pm_domain *imx_scu_pd_xlate(struct of_phandle_args *spec,
 212                                                   void *data)
 213 {
 214         struct generic_pm_domain *domain = ERR_PTR(-ENOENT);
 215         struct genpd_onecell_data *pd_data = data;
 216         unsigned int i;
 217 
 218         for (i = 0; i < pd_data->num_domains; i++) {
 219                 struct imx_sc_pm_domain *sc_pd;
 220 
 221                 sc_pd = to_imx_sc_pd(pd_data->domains[i]);
 222                 if (sc_pd->rsrc == spec->args[0]) {
 223                         domain = &sc_pd->pd;
 224                         break;
 225                 }
 226         }
 227 
 228         return domain;
 229 }
 230 
 231 static struct imx_sc_pm_domain *
 232 imx_scu_add_pm_domain(struct device *dev, int idx,
 233                       const struct imx_sc_pd_range *pd_ranges)
 234 {
 235         struct imx_sc_pm_domain *sc_pd;
 236         int ret;
 237 
 238         sc_pd = devm_kzalloc(dev, sizeof(*sc_pd), GFP_KERNEL);
 239         if (!sc_pd)
 240                 return ERR_PTR(-ENOMEM);
 241 
 242         sc_pd->rsrc = pd_ranges->rsrc + idx;
 243         sc_pd->pd.power_off = imx_sc_pd_power_off;
 244         sc_pd->pd.power_on = imx_sc_pd_power_on;
 245 
 246         if (pd_ranges->postfix)
 247                 snprintf(sc_pd->name, sizeof(sc_pd->name),
 248                          "%s%i", pd_ranges->name, pd_ranges->start_from + idx);
 249         else
 250                 snprintf(sc_pd->name, sizeof(sc_pd->name),
 251                          "%s", pd_ranges->name);
 252 
 253         sc_pd->pd.name = sc_pd->name;
 254 
 255         if (sc_pd->rsrc >= IMX_SC_R_LAST) {
 256                 dev_warn(dev, "invalid pd %s rsrc id %d found",
 257                          sc_pd->name, sc_pd->rsrc);
 258 
 259                 devm_kfree(dev, sc_pd);
 260                 return NULL;
 261         }
 262 
 263         ret = pm_genpd_init(&sc_pd->pd, NULL, true);
 264         if (ret) {
 265                 dev_warn(dev, "failed to init pd %s rsrc id %d",
 266                          sc_pd->name, sc_pd->rsrc);
 267                 devm_kfree(dev, sc_pd);
 268                 return NULL;
 269         }
 270 
 271         return sc_pd;
 272 }
 273 
 274 static int imx_scu_init_pm_domains(struct device *dev,
 275                                     const struct imx_sc_pd_soc *pd_soc)
 276 {
 277         const struct imx_sc_pd_range *pd_ranges = pd_soc->pd_ranges;
 278         struct generic_pm_domain **domains;
 279         struct genpd_onecell_data *pd_data;
 280         struct imx_sc_pm_domain *sc_pd;
 281         u32 count = 0;
 282         int i, j;
 283 
 284         for (i = 0; i < pd_soc->num_ranges; i++)
 285                 count += pd_ranges[i].num;
 286 
 287         domains = devm_kcalloc(dev, count, sizeof(*domains), GFP_KERNEL);
 288         if (!domains)
 289                 return -ENOMEM;
 290 
 291         pd_data = devm_kzalloc(dev, sizeof(*pd_data), GFP_KERNEL);
 292         if (!pd_data)
 293                 return -ENOMEM;
 294 
 295         count = 0;
 296         for (i = 0; i < pd_soc->num_ranges; i++) {
 297                 for (j = 0; j < pd_ranges[i].num; j++) {
 298                         sc_pd = imx_scu_add_pm_domain(dev, j, &pd_ranges[i]);
 299                         if (IS_ERR_OR_NULL(sc_pd))
 300                                 continue;
 301 
 302                         domains[count++] = &sc_pd->pd;
 303                         dev_dbg(dev, "added power domain %s\n", sc_pd->pd.name);
 304                 }
 305         }
 306 
 307         pd_data->domains = domains;
 308         pd_data->num_domains = count;
 309         pd_data->xlate = imx_scu_pd_xlate;
 310 
 311         of_genpd_add_provider_onecell(dev->of_node, pd_data);
 312 
 313         return 0;
 314 }
 315 
 316 static int imx_sc_pd_probe(struct platform_device *pdev)
 317 {
 318         const struct imx_sc_pd_soc *pd_soc;
 319         int ret;
 320 
 321         ret = imx_scu_get_handle(&pm_ipc_handle);
 322         if (ret)
 323                 return ret;
 324 
 325         pd_soc = of_device_get_match_data(&pdev->dev);
 326         if (!pd_soc)
 327                 return -ENODEV;
 328 
 329         return imx_scu_init_pm_domains(&pdev->dev, pd_soc);
 330 }
 331 
 332 static const struct of_device_id imx_sc_pd_match[] = {
 333         { .compatible = "fsl,imx8qxp-scu-pd", &imx8qxp_scu_pd},
 334         { .compatible = "fsl,scu-pd", &imx8qxp_scu_pd},
 335         { /* sentinel */ }
 336 };
 337 
 338 static struct platform_driver imx_sc_pd_driver = {
 339         .driver = {
 340                 .name = "imx-scu-pd",
 341                 .of_match_table = imx_sc_pd_match,
 342         },
 343         .probe = imx_sc_pd_probe,
 344 };
 345 builtin_platform_driver(imx_sc_pd_driver);
 346 
 347 MODULE_AUTHOR("Dong Aisheng <aisheng.dong@nxp.com>");
 348 MODULE_DESCRIPTION("IMX SCU Power Domain driver");
 349 MODULE_LICENSE("GPL v2");