drivers/cpufreq/tegra186-cpufreq.c

   1 /*
   2  * Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  */
  13
  14 #include <linux/cpufreq.h>
  15 #include <linux/dma-mapping.h>
  16 #include <linux/module.h>
  17 #include <linux/of.h>
  18 #include <linux/platform_device.h>
  19
  20 #include <soc/tegra/bpmp.h>
  21 #include <soc/tegra/bpmp-abi.h>
  22
  23 #define EDVD_CORE_VOLT_FREQ(core)               (0x20 + (core) * 0x4)
  24 #define EDVD_CORE_VOLT_FREQ_F_SHIFT             0
  25 #define EDVD_CORE_VOLT_FREQ_V_SHIFT             16
  26
  27 struct tegra186_cpufreq_cluster_info {
  28         unsigned long offset;
  29         int cpus[4];
  30         unsigned int bpmp_cluster_id;
  31 };
  32
  33 #define NO_CPU -1
  34 static const struct tegra186_cpufreq_cluster_info tegra186_clusters[] = {
  35         /* Denver cluster */
  36         {
  37                 .offset = SZ_64K * 7,
  38                 .cpus = { 1, 2, NO_CPU, NO_CPU },
  39                 .bpmp_cluster_id = 0,
  40         },
  41         /* A57 cluster */
  42         {
  43                 .offset = SZ_64K * 6,
  44                 .cpus = { 0, 3, 4, 5 },
  45                 .bpmp_cluster_id = 1,
  46         },
  47 };
  48
  49 struct tegra186_cpufreq_cluster {
  50         const struct tegra186_cpufreq_cluster_info *info;
  51         struct cpufreq_frequency_table *table;
  52 };
  53
  54 struct tegra186_cpufreq_data {
  55         void __iomem *regs;
  56
  57         size_t num_clusters;
  58         struct tegra186_cpufreq_cluster *clusters;
  59 };
  60
  61 static int tegra186_cpufreq_init(struct cpufreq_policy *policy)
  62 {
  63         struct tegra186_cpufreq_data *data = cpufreq_get_driver_data();
  64         unsigned int i;
  65
  66         for (i = 0; i < data->num_clusters; i++) {
  67                 struct tegra186_cpufreq_cluster *cluster = &data->clusters[i];
  68                 const struct tegra186_cpufreq_cluster_info *info =
  69                         cluster->info;
  70                 int core;
  71
  72                 for (core = 0; core < ARRAY_SIZE(info->cpus); core++) {
  73                         if (info->cpus[core] == policy->cpu)
  74                                 break;
  75                 }
  76                 if (core == ARRAY_SIZE(info->cpus))
  77                         continue;
  78
  79                 policy->driver_data =
  80                         data->regs + info->offset + EDVD_CORE_VOLT_FREQ(core);
  81                 cpufreq_table_validate_and_show(policy, cluster->table);
  82         }
  83
  84         policy->cpuinfo.transition_latency = 300 * 1000;
  85
  86         return 0;
  87 }
  88
  89 static int tegra186_cpufreq_set_target(struct cpufreq_policy *policy,
  90                                        unsigned int index)
  91 {
  92         struct cpufreq_frequency_table *tbl = policy->freq_table + index;
  93         void __iomem *edvd_reg = policy->driver_data;
  94         u32 edvd_val = tbl->driver_data;
  95
  96         writel(edvd_val, edvd_reg);
  97
  98         return 0;
  99 }
 100
 101 static struct cpufreq_driver tegra186_cpufreq_driver = {
 102         .name = "tegra186",
 103         .flags = CPUFREQ_STICKY | CPUFREQ_HAVE_GOVERNOR_PER_POLICY,
 104         .verify = cpufreq_generic_frequency_table_verify,
 105         .target_index = tegra186_cpufreq_set_target,
 106         .init = tegra186_cpufreq_init,
 107         .attr = cpufreq_generic_attr,
 108 };
 109
 110 static struct cpufreq_frequency_table *init_vhint_table(
 111         struct platform_device *pdev, struct tegra_bpmp *bpmp,
 112         unsigned int cluster_id)
 113 {
 114         struct cpufreq_frequency_table *table;
 115         struct mrq_cpu_vhint_request req;
 116         struct tegra_bpmp_message msg;
 117         struct cpu_vhint_data *data;
 118         int err, i, j, num_rates = 0;
 119         dma_addr_t phys;
 120         void *virt;
 121
 122         virt = dma_alloc_coherent(bpmp->dev, sizeof(*data), &phys,
 123                                   GFP_KERNEL | GFP_DMA32);
 124         if (!virt)
 125                 return ERR_PTR(-ENOMEM);
 126
 127         data = (struct cpu_vhint_data *)virt;
 128
 129         memset(&req, 0, sizeof(req));
 130         req.addr = phys;
 131         req.cluster_id = cluster_id;
 132
 133         memset(&msg, 0, sizeof(msg));
 134         msg.mrq = MRQ_CPU_VHINT;
 135         msg.tx.data = &req;
 136         msg.tx.size = sizeof(req);
 137
 138         err = tegra_bpmp_transfer(bpmp, &msg);
 139         if (err) {
 140                 table = ERR_PTR(err);
 141                 goto free;
 142         }
 143
 144         for (i = data->vfloor; i <= data->vceil; i++) {
 145                 u16 ndiv = data->ndiv[i];
 146
 147                 if (ndiv < data->ndiv_min || ndiv > data->ndiv_max)
 148                         continue;
 149
 150                 /* Only store lowest voltage index for each rate */
 151                 if (i > 0 && ndiv == data->ndiv[i - 1])
 152                         continue;
 153
 154                 num_rates++;
 155         }
 156
 157         table = devm_kcalloc(&pdev->dev, num_rates + 1, sizeof(*table),
 158                              GFP_KERNEL);
 159         if (!table) {
 160                 table = ERR_PTR(-ENOMEM);
 161                 goto free;
 162         }
 163
 164         for (i = data->vfloor, j = 0; i <= data->vceil; i++) {
 165                 struct cpufreq_frequency_table *point;
 166                 u16 ndiv = data->ndiv[i];
 167                 u32 edvd_val = 0;
 168
 169                 if (ndiv < data->ndiv_min || ndiv > data->ndiv_max)
 170                         continue;
 171
 172                 /* Only store lowest voltage index for each rate */
 173                 if (i > 0 && ndiv == data->ndiv[i - 1])
 174                         continue;
 175
 176                 edvd_val |= i << EDVD_CORE_VOLT_FREQ_V_SHIFT;
 177                 edvd_val |= ndiv << EDVD_CORE_VOLT_FREQ_F_SHIFT;
 178
 179                 point = &table[j++];
 180                 point->driver_data = edvd_val;
 181                 point->frequency = data->ref_clk_hz * ndiv / data->pdiv /
 182                         data->mdiv / 1000;
 183         }
 184
 185         table[j].frequency = CPUFREQ_TABLE_END;
 186
 187 free:
 188         dma_free_coherent(bpmp->dev, sizeof(*data), virt, phys);
 189
 190         return table;
 191 }
 192
 193 static int tegra186_cpufreq_probe(struct platform_device *pdev)
 194 {
 195         struct tegra186_cpufreq_data *data;
 196         struct tegra_bpmp *bpmp;
 197         struct resource *res;
 198         unsigned int i = 0, err;
 199
 200         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
 201         if (!data)
 202                 return -ENOMEM;
 203
 204         data->clusters = devm_kcalloc(&pdev->dev, ARRAY_SIZE(tegra186_clusters),
 205                                       sizeof(*data->clusters), GFP_KERNEL);
 206         if (!data->clusters)
 207                 return -ENOMEM;
 208
 209         data->num_clusters = ARRAY_SIZE(tegra186_clusters);
 210
 211         bpmp = tegra_bpmp_get(&pdev->dev);
 212         if (IS_ERR(bpmp))
 213                 return PTR_ERR(bpmp);
 214
 215         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 216         data->regs = devm_ioremap_resource(&pdev->dev, res);
 217         if (IS_ERR(data->regs)) {
 218                 err = PTR_ERR(data->regs);
 219                 goto put_bpmp;
 220         }
 221
 222         for (i = 0; i < data->num_clusters; i++) {
 223                 struct tegra186_cpufreq_cluster *cluster = &data->clusters[i];
 224
 225                 cluster->info = &tegra186_clusters[i];
 226                 cluster->table = init_vhint_table(
 227                         pdev, bpmp, cluster->info->bpmp_cluster_id);
 228                 if (IS_ERR(cluster->table)) {
 229                         err = PTR_ERR(cluster->table);
 230                         goto put_bpmp;
 231                 }
 232         }
 233
 234         tegra_bpmp_put(bpmp);
 235
 236         tegra186_cpufreq_driver.driver_data = data;
 237
 238         err = cpufreq_register_driver(&tegra186_cpufreq_driver);
 239         if (err)
 240                 return err;
 241
 242         return 0;
 243
 244 put_bpmp:
 245         tegra_bpmp_put(bpmp);
 246
 247         return err;
 248 }
 249
 250 static int tegra186_cpufreq_remove(struct platform_device *pdev)
 251 {
 252         cpufreq_unregister_driver(&tegra186_cpufreq_driver);
 253
 254         return 0;
 255 }
 256
 257 static const struct of_device_id tegra186_cpufreq_of_match[] = {
 258         { .compatible = "nvidia,tegra186-ccplex-cluster", },
 259         { }
 260 };
 261 MODULE_DEVICE_TABLE(of, tegra186_cpufreq_of_match);
 262
 263 static struct platform_driver tegra186_cpufreq_platform_driver = {
 264         .driver = {
 265                 .name = "tegra186-cpufreq",
 266                 .of_match_table = tegra186_cpufreq_of_match,
 267         },
 268         .probe = tegra186_cpufreq_probe,
 269         .remove = tegra186_cpufreq_remove,
 270 };
 271 module_platform_driver(tegra186_cpufreq_platform_driver);
 272
 273 MODULE_AUTHOR("Mikko Perttunen <mperttunen@nvidia.com>");
 274 MODULE_DESCRIPTION("NVIDIA Tegra186 cpufreq driver");
 275 MODULE_LICENSE("GPL v2");