linux/drivers/memory/of_memory.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * OpenFirmware helpers for memory drivers
   4 *
   5 * Copyright (C) 2012 Texas Instruments, Inc.
   6 * Copyright (C) 2019 Samsung Electronics Co., Ltd.
   7 */
   8
   9#include <linux/device.h>
  10#include <linux/platform_device.h>
  11#include <linux/list.h>
  12#include <linux/of.h>
  13#include <linux/gfp.h>
  14#include <linux/export.h>
  15
  16#include "jedec_ddr.h"
  17#include "of_memory.h"
  18
  19/**
  20 * of_get_min_tck() - extract min timing values for ddr
  21 * @np: pointer to ddr device tree node
  22 * @device: device requesting for min timing values
  23 *
  24 * Populates the lpddr2_min_tck structure by extracting data
  25 * from device tree node. Returns a pointer to the populated
  26 * structure. If any error in populating the structure, returns
  27 * default min timings provided by JEDEC.
  28 */
  29const struct lpddr2_min_tck *of_get_min_tck(struct device_node *np,
  30                struct device *dev)
  31{
  32        int                     ret = 0;
  33        struct lpddr2_min_tck   *min;
  34
  35        min = devm_kzalloc(dev, sizeof(*min), GFP_KERNEL);
  36        if (!min)
  37                goto default_min_tck;
  38
  39        ret |= of_property_read_u32(np, "tRPab-min-tck", &min->tRPab);
  40        ret |= of_property_read_u32(np, "tRCD-min-tck", &min->tRCD);
  41        ret |= of_property_read_u32(np, "tWR-min-tck", &min->tWR);
  42        ret |= of_property_read_u32(np, "tRASmin-min-tck", &min->tRASmin);
  43        ret |= of_property_read_u32(np, "tRRD-min-tck", &min->tRRD);
  44        ret |= of_property_read_u32(np, "tWTR-min-tck", &min->tWTR);
  45        ret |= of_property_read_u32(np, "tXP-min-tck", &min->tXP);
  46        ret |= of_property_read_u32(np, "tRTP-min-tck", &min->tRTP);
  47        ret |= of_property_read_u32(np, "tCKE-min-tck", &min->tCKE);
  48        ret |= of_property_read_u32(np, "tCKESR-min-tck", &min->tCKESR);
  49        ret |= of_property_read_u32(np, "tFAW-min-tck", &min->tFAW);
  50
  51        if (ret) {
  52                devm_kfree(dev, min);
  53                goto default_min_tck;
  54        }
  55
  56        return min;
  57
  58default_min_tck:
  59        dev_warn(dev, "%s: using default min-tck values\n", __func__);
  60        return &lpddr2_jedec_min_tck;
  61}
  62EXPORT_SYMBOL(of_get_min_tck);
  63
  64static int of_do_get_timings(struct device_node *np,
  65                struct lpddr2_timings *tim)
  66{
  67        int ret;
  68
  69        ret = of_property_read_u32(np, "max-freq", &tim->max_freq);
  70        ret |= of_property_read_u32(np, "min-freq", &tim->min_freq);
  71        ret |= of_property_read_u32(np, "tRPab", &tim->tRPab);
  72        ret |= of_property_read_u32(np, "tRCD", &tim->tRCD);
  73        ret |= of_property_read_u32(np, "tWR", &tim->tWR);
  74        ret |= of_property_read_u32(np, "tRAS-min", &tim->tRAS_min);
  75        ret |= of_property_read_u32(np, "tRRD", &tim->tRRD);
  76        ret |= of_property_read_u32(np, "tWTR", &tim->tWTR);
  77        ret |= of_property_read_u32(np, "tXP", &tim->tXP);
  78        ret |= of_property_read_u32(np, "tRTP", &tim->tRTP);
  79        ret |= of_property_read_u32(np, "tCKESR", &tim->tCKESR);
  80        ret |= of_property_read_u32(np, "tDQSCK-max", &tim->tDQSCK_max);
  81        ret |= of_property_read_u32(np, "tFAW", &tim->tFAW);
  82        ret |= of_property_read_u32(np, "tZQCS", &tim->tZQCS);
  83        ret |= of_property_read_u32(np, "tZQCL", &tim->tZQCL);
  84        ret |= of_property_read_u32(np, "tZQinit", &tim->tZQinit);
  85        ret |= of_property_read_u32(np, "tRAS-max-ns", &tim->tRAS_max_ns);
  86        ret |= of_property_read_u32(np, "tDQSCK-max-derated",
  87                &tim->tDQSCK_max_derated);
  88
  89        return ret;
  90}
  91
  92/**
  93 * of_get_ddr_timings() - extracts the ddr timings and updates no of
  94 * frequencies available.
  95 * @np_ddr: Pointer to ddr device tree node
  96 * @dev: Device requesting for ddr timings
  97 * @device_type: Type of ddr(LPDDR2 S2/S4)
  98 * @nr_frequencies: No of frequencies available for ddr
  99 * (updated by this function)
 100 *
 101 * Populates lpddr2_timings structure by extracting data from device
 102 * tree node. Returns pointer to populated structure. If any error
 103 * while populating, returns default timings provided by JEDEC.
 104 */
 105const struct lpddr2_timings *of_get_ddr_timings(struct device_node *np_ddr,
 106                struct device *dev, u32 device_type, u32 *nr_frequencies)
 107{
 108        struct lpddr2_timings   *timings = NULL;
 109        u32                     arr_sz = 0, i = 0;
 110        struct device_node      *np_tim;
 111        char                    *tim_compat = NULL;
 112
 113        switch (device_type) {
 114        case DDR_TYPE_LPDDR2_S2:
 115        case DDR_TYPE_LPDDR2_S4:
 116                tim_compat = "jedec,lpddr2-timings";
 117                break;
 118        default:
 119                dev_warn(dev, "%s: un-supported memory type\n", __func__);
 120        }
 121
 122        for_each_child_of_node(np_ddr, np_tim)
 123                if (of_device_is_compatible(np_tim, tim_compat))
 124                        arr_sz++;
 125
 126        if (arr_sz)
 127                timings = devm_kcalloc(dev, arr_sz, sizeof(*timings),
 128                                       GFP_KERNEL);
 129
 130        if (!timings)
 131                goto default_timings;
 132
 133        for_each_child_of_node(np_ddr, np_tim) {
 134                if (of_device_is_compatible(np_tim, tim_compat)) {
 135                        if (of_do_get_timings(np_tim, &timings[i])) {
 136                                devm_kfree(dev, timings);
 137                                goto default_timings;
 138                        }
 139                        i++;
 140                }
 141        }
 142
 143        *nr_frequencies = arr_sz;
 144
 145        return timings;
 146
 147default_timings:
 148        dev_warn(dev, "%s: using default timings\n", __func__);
 149        *nr_frequencies = ARRAY_SIZE(lpddr2_jedec_timings);
 150        return lpddr2_jedec_timings;
 151}
 152EXPORT_SYMBOL(of_get_ddr_timings);
 153
 154/**
 155 * of_lpddr3_get_min_tck() - extract min timing values for lpddr3
 156 * @np: pointer to ddr device tree node
 157 * @device: device requesting for min timing values
 158 *
 159 * Populates the lpddr3_min_tck structure by extracting data
 160 * from device tree node. Returns a pointer to the populated
 161 * structure. If any error in populating the structure, returns NULL.
 162 */
 163const struct lpddr3_min_tck *of_lpddr3_get_min_tck(struct device_node *np,
 164                                                   struct device *dev)
 165{
 166        int                     ret = 0;
 167        struct lpddr3_min_tck   *min;
 168
 169        min = devm_kzalloc(dev, sizeof(*min), GFP_KERNEL);
 170        if (!min)
 171                goto default_min_tck;
 172
 173        ret |= of_property_read_u32(np, "tRFC-min-tck", &min->tRFC);
 174        ret |= of_property_read_u32(np, "tRRD-min-tck", &min->tRRD);
 175        ret |= of_property_read_u32(np, "tRPab-min-tck", &min->tRPab);
 176        ret |= of_property_read_u32(np, "tRPpb-min-tck", &min->tRPpb);
 177        ret |= of_property_read_u32(np, "tRCD-min-tck", &min->tRCD);
 178        ret |= of_property_read_u32(np, "tRC-min-tck", &min->tRC);
 179        ret |= of_property_read_u32(np, "tRAS-min-tck", &min->tRAS);
 180        ret |= of_property_read_u32(np, "tWTR-min-tck", &min->tWTR);
 181        ret |= of_property_read_u32(np, "tWR-min-tck", &min->tWR);
 182        ret |= of_property_read_u32(np, "tRTP-min-tck", &min->tRTP);
 183        ret |= of_property_read_u32(np, "tW2W-C2C-min-tck", &min->tW2W_C2C);
 184        ret |= of_property_read_u32(np, "tR2R-C2C-min-tck", &min->tR2R_C2C);
 185        ret |= of_property_read_u32(np, "tWL-min-tck", &min->tWL);
 186        ret |= of_property_read_u32(np, "tDQSCK-min-tck", &min->tDQSCK);
 187        ret |= of_property_read_u32(np, "tRL-min-tck", &min->tRL);
 188        ret |= of_property_read_u32(np, "tFAW-min-tck", &min->tFAW);
 189        ret |= of_property_read_u32(np, "tXSR-min-tck", &min->tXSR);
 190        ret |= of_property_read_u32(np, "tXP-min-tck", &min->tXP);
 191        ret |= of_property_read_u32(np, "tCKE-min-tck", &min->tCKE);
 192        ret |= of_property_read_u32(np, "tCKESR-min-tck", &min->tCKESR);
 193        ret |= of_property_read_u32(np, "tMRD-min-tck", &min->tMRD);
 194
 195        if (ret) {
 196                dev_warn(dev, "%s: errors while parsing min-tck values\n",
 197                         __func__);
 198                devm_kfree(dev, min);
 199                goto default_min_tck;
 200        }
 201
 202        return min;
 203
 204default_min_tck:
 205        dev_warn(dev, "%s: using default min-tck values\n", __func__);
 206        return NULL;
 207}
 208EXPORT_SYMBOL(of_lpddr3_get_min_tck);
 209
 210static int of_lpddr3_do_get_timings(struct device_node *np,
 211                                    struct lpddr3_timings *tim)
 212{
 213        int ret;
 214
 215        /* The 'reg' param required since DT has changed, used as 'max-freq' */
 216        ret = of_property_read_u32(np, "reg", &tim->max_freq);
 217        ret |= of_property_read_u32(np, "min-freq", &tim->min_freq);
 218        ret |= of_property_read_u32(np, "tRFC", &tim->tRFC);
 219        ret |= of_property_read_u32(np, "tRRD", &tim->tRRD);
 220        ret |= of_property_read_u32(np, "tRPab", &tim->tRPab);
 221        ret |= of_property_read_u32(np, "tRPpb", &tim->tRPpb);
 222        ret |= of_property_read_u32(np, "tRCD", &tim->tRCD);
 223        ret |= of_property_read_u32(np, "tRC", &tim->tRC);
 224        ret |= of_property_read_u32(np, "tRAS", &tim->tRAS);
 225        ret |= of_property_read_u32(np, "tWTR", &tim->tWTR);
 226        ret |= of_property_read_u32(np, "tWR", &tim->tWR);
 227        ret |= of_property_read_u32(np, "tRTP", &tim->tRTP);
 228        ret |= of_property_read_u32(np, "tW2W-C2C", &tim->tW2W_C2C);
 229        ret |= of_property_read_u32(np, "tR2R-C2C", &tim->tR2R_C2C);
 230        ret |= of_property_read_u32(np, "tFAW", &tim->tFAW);
 231        ret |= of_property_read_u32(np, "tXSR", &tim->tXSR);
 232        ret |= of_property_read_u32(np, "tXP", &tim->tXP);
 233        ret |= of_property_read_u32(np, "tCKE", &tim->tCKE);
 234        ret |= of_property_read_u32(np, "tCKESR", &tim->tCKESR);
 235        ret |= of_property_read_u32(np, "tMRD", &tim->tMRD);
 236
 237        return ret;
 238}
 239
 240/**
 241 * of_lpddr3_get_ddr_timings() - extracts the lpddr3 timings and updates no of
 242 * frequencies available.
 243 * @np_ddr: Pointer to ddr device tree node
 244 * @dev: Device requesting for ddr timings
 245 * @device_type: Type of ddr
 246 * @nr_frequencies: No of frequencies available for ddr
 247 * (updated by this function)
 248 *
 249 * Populates lpddr3_timings structure by extracting data from device
 250 * tree node. Returns pointer to populated structure. If any error
 251 * while populating, returns NULL.
 252 */
 253const struct lpddr3_timings
 254*of_lpddr3_get_ddr_timings(struct device_node *np_ddr, struct device *dev,
 255                           u32 device_type, u32 *nr_frequencies)
 256{
 257        struct lpddr3_timings   *timings = NULL;
 258        u32                     arr_sz = 0, i = 0;
 259        struct device_node      *np_tim;
 260        char                    *tim_compat = NULL;
 261
 262        switch (device_type) {
 263        case DDR_TYPE_LPDDR3:
 264                tim_compat = "jedec,lpddr3-timings";
 265                break;
 266        default:
 267                dev_warn(dev, "%s: un-supported memory type\n", __func__);
 268        }
 269
 270        for_each_child_of_node(np_ddr, np_tim)
 271                if (of_device_is_compatible(np_tim, tim_compat))
 272                        arr_sz++;
 273
 274        if (arr_sz)
 275                timings = devm_kcalloc(dev, arr_sz, sizeof(*timings),
 276                                       GFP_KERNEL);
 277
 278        if (!timings)
 279                goto default_timings;
 280
 281        for_each_child_of_node(np_ddr, np_tim) {
 282                if (of_device_is_compatible(np_tim, tim_compat)) {
 283                        if (of_lpddr3_do_get_timings(np_tim, &timings[i])) {
 284                                devm_kfree(dev, timings);
 285                                goto default_timings;
 286                        }
 287                        i++;
 288                }
 289        }
 290
 291        *nr_frequencies = arr_sz;
 292
 293        return timings;
 294
 295default_timings:
 296        dev_warn(dev, "%s: failed to get timings\n", __func__);
 297        *nr_frequencies = 0;
 298        return NULL;
 299}
 300EXPORT_SYMBOL(of_lpddr3_get_ddr_timings);
 301