drivers/phy/phy-stm32-usbphyc.c

   1 // SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
   2 /*
   3  * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
   4  */
   5
   6 #include <common.h>
   7 #include <clk.h>
   8 #include <div64.h>
   9 #include <dm.h>
  10 #include <fdtdec.h>
  11 #include <generic-phy.h>
  12 #include <log.h>
  13 #include <reset.h>
  14 #include <syscon.h>
  15 #include <usb.h>
  16 #include <asm/io.h>
  17 #include <dm/device_compat.h>
  18 #include <linux/bitops.h>
  19 #include <linux/delay.h>
  20 #include <power/regulator.h>
  21
  22 /* USBPHYC registers */
  23 #define STM32_USBPHYC_PLL       0x0
  24 #define STM32_USBPHYC_MISC      0x8
  25
  26 /* STM32_USBPHYC_PLL bit fields */
  27 #define PLLNDIV                 GENMASK(6, 0)
  28 #define PLLNDIV_SHIFT           0
  29 #define PLLFRACIN               GENMASK(25, 10)
  30 #define PLLFRACIN_SHIFT         10
  31 #define PLLEN                   BIT(26)
  32 #define PLLSTRB                 BIT(27)
  33 #define PLLSTRBYP               BIT(28)
  34 #define PLLFRACCTL              BIT(29)
  35 #define PLLDITHEN0              BIT(30)
  36 #define PLLDITHEN1              BIT(31)
  37
  38 /* STM32_USBPHYC_MISC bit fields */
  39 #define SWITHOST                BIT(0)
  40
  41 #define MAX_PHYS                2
  42
  43 /* max 100 us for PLL lock and 100 us for PHY init */
  44 #define PLL_INIT_TIME_US        200
  45 #define PLL_PWR_DOWN_TIME_US    5
  46 #define PLL_FVCO                2880     /* in MHz */
  47 #define PLL_INFF_MIN_RATE       19200000 /* in Hz */
  48 #define PLL_INFF_MAX_RATE       38400000 /* in Hz */
  49
  50 struct pll_params {
  51         u8 ndiv;
  52         u16 frac;
  53 };
  54
  55 struct stm32_usbphyc {
  56         fdt_addr_t base;
  57         struct clk clk;
  58         struct udevice *vdda1v1;
  59         struct udevice *vdda1v8;
  60         struct stm32_usbphyc_phy {
  61                 struct udevice *vdd;
  62                 struct udevice *vbus;
  63                 bool init;
  64                 bool powered;
  65         } phys[MAX_PHYS];
  66 };
  67
  68 static void stm32_usbphyc_get_pll_params(u32 clk_rate,
  69                                          struct pll_params *pll_params)
  70 {
  71         unsigned long long fvco, ndiv, frac;
  72
  73         /*
  74          *    | FVCO = INFF*2*(NDIV + FRACT/2^16 ) when DITHER_DISABLE[1] = 1
  75          *    | FVCO = 2880MHz
  76          *    | NDIV = integer part of input bits to set the LDF
  77          *    | FRACT = fractional part of input bits to set the LDF
  78          *  =>  PLLNDIV = integer part of (FVCO / (INFF*2))
  79          *  =>  PLLFRACIN = fractional part of(FVCO / INFF*2) * 2^16
  80          * <=>  PLLFRACIN = ((FVCO / (INFF*2)) - PLLNDIV) * 2^16
  81          */
  82         fvco = (unsigned long long)PLL_FVCO * 1000000; /* In Hz */
  83
  84         ndiv = fvco;
  85         do_div(ndiv, (clk_rate * 2));
  86         pll_params->ndiv = (u8)ndiv;
  87
  88         frac = fvco * (1 << 16);
  89         do_div(frac, (clk_rate * 2));
  90         frac = frac - (ndiv * (1 << 16));
  91         pll_params->frac = (u16)frac;
  92 }
  93
  94 static int stm32_usbphyc_pll_init(struct stm32_usbphyc *usbphyc)
  95 {
  96         struct pll_params pll_params;
  97         u32 clk_rate = clk_get_rate(&usbphyc->clk);
  98         u32 usbphyc_pll;
  99
 100         if ((clk_rate < PLL_INFF_MIN_RATE) || (clk_rate > PLL_INFF_MAX_RATE)) {
 101                 pr_debug("%s: input clk freq (%dHz) out of range\n",
 102                          __func__, clk_rate);
 103                 return -EINVAL;
 104         }
 105
 106         stm32_usbphyc_get_pll_params(clk_rate, &pll_params);
 107
 108         usbphyc_pll = PLLDITHEN1 | PLLDITHEN0 | PLLSTRBYP;
 109         usbphyc_pll |= ((pll_params.ndiv << PLLNDIV_SHIFT) & PLLNDIV);
 110
 111         if (pll_params.frac) {
 112                 usbphyc_pll |= PLLFRACCTL;
 113                 usbphyc_pll |= ((pll_params.frac << PLLFRACIN_SHIFT)
 114                                  & PLLFRACIN);
 115         }
 116
 117         writel(usbphyc_pll, usbphyc->base + STM32_USBPHYC_PLL);
 118
 119         pr_debug("%s: input clk freq=%dHz, ndiv=%d, frac=%d\n", __func__,
 120                  clk_rate, pll_params.ndiv, pll_params.frac);
 121
 122         return 0;
 123 }
 124
 125 static bool stm32_usbphyc_is_init(struct stm32_usbphyc *usbphyc)
 126 {
 127         int i;
 128
 129         for (i = 0; i < MAX_PHYS; i++) {
 130                 if (usbphyc->phys[i].init)
 131                         return true;
 132         }
 133
 134         return false;
 135 }
 136
 137 static bool stm32_usbphyc_is_powered(struct stm32_usbphyc *usbphyc)
 138 {
 139         int i;
 140
 141         for (i = 0; i < MAX_PHYS; i++) {
 142                 if (usbphyc->phys[i].powered)
 143                         return true;
 144         }
 145
 146         return false;
 147 }
 148
 149 static int stm32_usbphyc_phy_init(struct phy *phy)
 150 {
 151         struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
 152         struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
 153         bool pllen = readl(usbphyc->base + STM32_USBPHYC_PLL) & PLLEN ?
 154                      true : false;
 155         int ret;
 156
 157         pr_debug("%s phy ID = %lu\n", __func__, phy->id);
 158         /* Check if one phy port has already configured the pll */
 159         if (pllen && stm32_usbphyc_is_init(usbphyc))
 160                 goto initialized;
 161
 162         if (usbphyc->vdda1v1) {
 163                 ret = regulator_set_enable(usbphyc->vdda1v1, true);
 164                 if (ret)
 165                         return ret;
 166         }
 167
 168         if (usbphyc->vdda1v8) {
 169                 ret = regulator_set_enable(usbphyc->vdda1v8, true);
 170                 if (ret)
 171                         return ret;
 172         }
 173
 174         if (pllen) {
 175                 clrbits_le32(usbphyc->base + STM32_USBPHYC_PLL, PLLEN);
 176                 udelay(PLL_PWR_DOWN_TIME_US);
 177         }
 178
 179         ret = stm32_usbphyc_pll_init(usbphyc);
 180         if (ret)
 181                 return ret;
 182
 183         setbits_le32(usbphyc->base + STM32_USBPHYC_PLL, PLLEN);
 184
 185         /* We must wait PLL_INIT_TIME_US before using PHY */
 186         udelay(PLL_INIT_TIME_US);
 187
 188         if (!(readl(usbphyc->base + STM32_USBPHYC_PLL) & PLLEN))
 189                 return -EIO;
 190
 191 initialized:
 192         usbphyc_phy->init = true;
 193
 194         return 0;
 195 }
 196
 197 static int stm32_usbphyc_phy_exit(struct phy *phy)
 198 {
 199         struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
 200         struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
 201         int ret;
 202
 203         pr_debug("%s phy ID = %lu\n", __func__, phy->id);
 204         usbphyc_phy->init = false;
 205
 206         /* Check if other phy port requires pllen */
 207         if (stm32_usbphyc_is_init(usbphyc))
 208                 return 0;
 209
 210         clrbits_le32(usbphyc->base + STM32_USBPHYC_PLL, PLLEN);
 211
 212         /*
 213          * We must wait PLL_PWR_DOWN_TIME_US before checking that PLLEN
 214          * bit is still clear
 215          */
 216         udelay(PLL_PWR_DOWN_TIME_US);
 217
 218         if (readl(usbphyc->base + STM32_USBPHYC_PLL) & PLLEN)
 219                 return -EIO;
 220
 221         if (usbphyc->vdda1v1) {
 222                 ret = regulator_set_enable(usbphyc->vdda1v1, false);
 223                 if (ret)
 224                         return ret;
 225         }
 226
 227         if (usbphyc->vdda1v8) {
 228                 ret = regulator_set_enable(usbphyc->vdda1v8, false);
 229                 if (ret)
 230                         return ret;
 231         }
 232
 233         return 0;
 234 }
 235
 236 static int stm32_usbphyc_phy_power_on(struct phy *phy)
 237 {
 238         struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
 239         struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
 240         int ret;
 241
 242         pr_debug("%s phy ID = %lu\n", __func__, phy->id);
 243         if (usbphyc_phy->vdd) {
 244                 ret = regulator_set_enable(usbphyc_phy->vdd, true);
 245                 if (ret)
 246                         return ret;
 247         }
 248         if (usbphyc_phy->vbus) {
 249                 ret = regulator_set_enable(usbphyc_phy->vbus, true);
 250                 if (ret)
 251                         return ret;
 252         }
 253
 254         usbphyc_phy->powered = true;
 255
 256         return 0;
 257 }
 258
 259 static int stm32_usbphyc_phy_power_off(struct phy *phy)
 260 {
 261         struct stm32_usbphyc *usbphyc = dev_get_priv(phy->dev);
 262         struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + phy->id;
 263         int ret;
 264
 265         pr_debug("%s phy ID = %lu\n", __func__, phy->id);
 266         usbphyc_phy->powered = false;
 267
 268         if (stm32_usbphyc_is_powered(usbphyc))
 269                 return 0;
 270
 271         if (usbphyc_phy->vbus) {
 272                 ret = regulator_set_enable(usbphyc_phy->vbus, false);
 273                 if (ret)
 274                         return ret;
 275         }
 276         if (usbphyc_phy->vdd) {
 277                 ret = regulator_set_enable_if_allowed(usbphyc_phy->vdd, false);
 278                 if (ret)
 279                         return ret;
 280         }
 281
 282         return 0;
 283 }
 284
 285 static int stm32_usbphyc_get_regulator(ofnode node,
 286                                        char *supply_name,
 287                                        struct udevice **regulator)
 288 {
 289         struct ofnode_phandle_args regulator_phandle;
 290         int ret;
 291
 292         ret = ofnode_parse_phandle_with_args(node, supply_name,
 293                                              NULL, 0, 0,
 294                                              &regulator_phandle);
 295         if (ret)
 296                 return ret;
 297
 298         ret = uclass_get_device_by_ofnode(UCLASS_REGULATOR,
 299                                           regulator_phandle.node,
 300                                           regulator);
 301         if (ret)
 302                 return ret;
 303
 304         return 0;
 305 }
 306
 307 static int stm32_usbphyc_of_xlate(struct phy *phy,
 308                                   struct ofnode_phandle_args *args)
 309 {
 310         if (args->args_count < 1)
 311                 return -ENODEV;
 312
 313         if (args->args[0] >= MAX_PHYS)
 314                 return -ENODEV;
 315
 316         phy->id = args->args[0];
 317
 318         if ((phy->id == 0 && args->args_count != 1) ||
 319             (phy->id == 1 && args->args_count != 2)) {
 320                 dev_err(phy->dev, "invalid number of cells for phy port%ld\n",
 321                         phy->id);
 322                 return -EINVAL;
 323         }
 324
 325         return 0;
 326 }
 327
 328 static const struct phy_ops stm32_usbphyc_phy_ops = {
 329         .init = stm32_usbphyc_phy_init,
 330         .exit = stm32_usbphyc_phy_exit,
 331         .power_on = stm32_usbphyc_phy_power_on,
 332         .power_off = stm32_usbphyc_phy_power_off,
 333         .of_xlate = stm32_usbphyc_of_xlate,
 334 };
 335
 336 static int stm32_usbphyc_probe(struct udevice *dev)
 337 {
 338         struct stm32_usbphyc *usbphyc = dev_get_priv(dev);
 339         struct reset_ctl reset;
 340         ofnode node;
 341         int i, ret;
 342
 343         usbphyc->base = dev_read_addr(dev);
 344         if (usbphyc->base == FDT_ADDR_T_NONE)
 345                 return -EINVAL;
 346
 347         /* Enable clock */
 348         ret = clk_get_by_index(dev, 0, &usbphyc->clk);
 349         if (ret)
 350                 return ret;
 351
 352         ret = clk_enable(&usbphyc->clk);
 353         if (ret)
 354                 return ret;
 355
 356         /* Reset */
 357         ret = reset_get_by_index(dev, 0, &reset);
 358         if (!ret) {
 359                 reset_assert(&reset);
 360                 udelay(2);
 361                 reset_deassert(&reset);
 362         }
 363
 364         /* get usbphyc regulator */
 365         ret = device_get_supply_regulator(dev, "vdda1v1-supply",
 366                                           &usbphyc->vdda1v1);
 367         if (ret) {
 368                 dev_err(dev, "Can't get vdda1v1-supply regulator\n");
 369                 return ret;
 370         }
 371
 372         ret = device_get_supply_regulator(dev, "vdda1v8-supply",
 373                                           &usbphyc->vdda1v8);
 374         if (ret) {
 375                 dev_err(dev, "Can't get vdda1v8-supply regulator\n");
 376                 return ret;
 377         }
 378
 379         /*
 380          * parse all PHY subnodes in order to populate regulator associated
 381          * to each PHY port
 382          */
 383         node = dev_read_first_subnode(dev);
 384         for (i = 0; i < MAX_PHYS; i++) {
 385                 struct stm32_usbphyc_phy *usbphyc_phy = usbphyc->phys + i;
 386
 387                 usbphyc_phy->init = false;
 388                 usbphyc_phy->powered = false;
 389                 ret = stm32_usbphyc_get_regulator(node, "phy-supply",
 390                                                   &usbphyc_phy->vdd);
 391                 if (ret) {
 392                         dev_err(dev, "Can't get phy-supply regulator\n");
 393                         return ret;
 394                 }
 395
 396                 ret = stm32_usbphyc_get_regulator(node, "vbus-supply",
 397                                                   &usbphyc_phy->vbus);
 398                 if (ret)
 399                         usbphyc_phy->vbus = NULL;
 400
 401                 node = dev_read_next_subnode(node);
 402         }
 403
 404         /* Check if second port has to be used for host controller */
 405         if (dev_read_bool(dev, "st,port2-switch-to-host"))
 406                 setbits_le32(usbphyc->base + STM32_USBPHYC_MISC, SWITHOST);
 407
 408         return 0;
 409 }
 410
 411 static const struct udevice_id stm32_usbphyc_of_match[] = {
 412         { .compatible = "st,stm32mp1-usbphyc", },
 413         { },
 414 };
 415
 416 U_BOOT_DRIVER(stm32_usb_phyc) = {
 417         .name = "stm32-usbphyc",
 418         .id = UCLASS_PHY,
 419         .of_match = stm32_usbphyc_of_match,
 420         .ops = &stm32_usbphyc_phy_ops,
 421         .probe = stm32_usbphyc_probe,
 422         .priv_auto      = sizeof(struct stm32_usbphyc),
 423 };