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