linux/arch/powerpc/platforms/powernv/opal-imc.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * OPAL IMC interface detection driver
   4 * Supported on POWERNV platform
   5 *
   6 * Copyright    (C) 2017 Madhavan Srinivasan, IBM Corporation.
   7 *              (C) 2017 Anju T Sudhakar, IBM Corporation.
   8 *              (C) 2017 Hemant K Shaw, IBM Corporation.
   9 */
  10#include <linux/kernel.h>
  11#include <linux/platform_device.h>
  12#include <linux/of.h>
  13#include <linux/of_address.h>
  14#include <linux/of_platform.h>
  15#include <linux/crash_dump.h>
  16#include <linux/debugfs.h>
  17#include <asm/opal.h>
  18#include <asm/io.h>
  19#include <asm/imc-pmu.h>
  20#include <asm/cputhreads.h>
  21
  22static struct dentry *imc_debugfs_parent;
  23
  24/* Helpers to export imc command and mode via debugfs */
  25static int imc_mem_get(void *data, u64 *val)
  26{
  27        *val = cpu_to_be64(*(u64 *)data);
  28        return 0;
  29}
  30
  31static int imc_mem_set(void *data, u64 val)
  32{
  33        *(u64 *)data = cpu_to_be64(val);
  34        return 0;
  35}
  36DEFINE_DEBUGFS_ATTRIBUTE(fops_imc_x64, imc_mem_get, imc_mem_set, "0x%016llx\n");
  37
  38static void imc_debugfs_create_x64(const char *name, umode_t mode,
  39                                   struct dentry *parent, u64  *value)
  40{
  41        debugfs_create_file_unsafe(name, mode, parent, value, &fops_imc_x64);
  42}
  43
  44/*
  45 * export_imc_mode_and_cmd: Create a debugfs interface
  46 *                     for imc_cmd and imc_mode
  47 *                     for each node in the system.
  48 *  imc_mode and imc_cmd can be changed by echo into
  49 *  this interface.
  50 */
  51static void export_imc_mode_and_cmd(struct device_node *node,
  52                                    struct imc_pmu *pmu_ptr)
  53{
  54        static u64 loc, *imc_mode_addr, *imc_cmd_addr;
  55        char mode[16], cmd[16];
  56        u32 cb_offset;
  57        struct imc_mem_info *ptr = pmu_ptr->mem_info;
  58
  59        imc_debugfs_parent = debugfs_create_dir("imc", arch_debugfs_dir);
  60
  61        if (of_property_read_u32(node, "cb_offset", &cb_offset))
  62                cb_offset = IMC_CNTL_BLK_OFFSET;
  63
  64        while (ptr->vbase != NULL) {
  65                loc = (u64)(ptr->vbase) + cb_offset;
  66                imc_mode_addr = (u64 *)(loc + IMC_CNTL_BLK_MODE_OFFSET);
  67                sprintf(mode, "imc_mode_%d", (u32)(ptr->id));
  68                imc_debugfs_create_x64(mode, 0600, imc_debugfs_parent,
  69                                       imc_mode_addr);
  70
  71                imc_cmd_addr = (u64 *)(loc + IMC_CNTL_BLK_CMD_OFFSET);
  72                sprintf(cmd, "imc_cmd_%d", (u32)(ptr->id));
  73                imc_debugfs_create_x64(cmd, 0600, imc_debugfs_parent,
  74                                       imc_cmd_addr);
  75                ptr++;
  76        }
  77}
  78
  79/*
  80 * imc_get_mem_addr_nest: Function to get nest counter memory region
  81 * for each chip
  82 */
  83static int imc_get_mem_addr_nest(struct device_node *node,
  84                                 struct imc_pmu *pmu_ptr,
  85                                 u32 offset)
  86{
  87        int nr_chips = 0, i;
  88        u64 *base_addr_arr, baddr;
  89        u32 *chipid_arr;
  90
  91        nr_chips = of_property_count_u32_elems(node, "chip-id");
  92        if (nr_chips <= 0)
  93                return -ENODEV;
  94
  95        base_addr_arr = kcalloc(nr_chips, sizeof(*base_addr_arr), GFP_KERNEL);
  96        if (!base_addr_arr)
  97                return -ENOMEM;
  98
  99        chipid_arr = kcalloc(nr_chips, sizeof(*chipid_arr), GFP_KERNEL);
 100        if (!chipid_arr) {
 101                kfree(base_addr_arr);
 102                return -ENOMEM;
 103        }
 104
 105        if (of_property_read_u32_array(node, "chip-id", chipid_arr, nr_chips))
 106                goto error;
 107
 108        if (of_property_read_u64_array(node, "base-addr", base_addr_arr,
 109                                                                nr_chips))
 110                goto error;
 111
 112        pmu_ptr->mem_info = kcalloc(nr_chips + 1, sizeof(*pmu_ptr->mem_info),
 113                                    GFP_KERNEL);
 114        if (!pmu_ptr->mem_info)
 115                goto error;
 116
 117        for (i = 0; i < nr_chips; i++) {
 118                pmu_ptr->mem_info[i].id = chipid_arr[i];
 119                baddr = base_addr_arr[i] + offset;
 120                pmu_ptr->mem_info[i].vbase = phys_to_virt(baddr);
 121        }
 122
 123        pmu_ptr->imc_counter_mmaped = true;
 124        kfree(base_addr_arr);
 125        kfree(chipid_arr);
 126        return 0;
 127
 128error:
 129        kfree(base_addr_arr);
 130        kfree(chipid_arr);
 131        return -1;
 132}
 133
 134/*
 135 * imc_pmu_create : Takes the parent device which is the pmu unit, pmu_index
 136 *                  and domain as the inputs.
 137 * Allocates memory for the struct imc_pmu, sets up its domain, size and offsets
 138 */
 139static struct imc_pmu *imc_pmu_create(struct device_node *parent, int pmu_index, int domain)
 140{
 141        int ret = 0;
 142        struct imc_pmu *pmu_ptr;
 143        u32 offset;
 144
 145        /* Return for unknown domain */
 146        if (domain < 0)
 147                return NULL;
 148
 149        /* memory for pmu */
 150        pmu_ptr = kzalloc(sizeof(*pmu_ptr), GFP_KERNEL);
 151        if (!pmu_ptr)
 152                return NULL;
 153
 154        /* Set the domain */
 155        pmu_ptr->domain = domain;
 156
 157        ret = of_property_read_u32(parent, "size", &pmu_ptr->counter_mem_size);
 158        if (ret)
 159                goto free_pmu;
 160
 161        if (!of_property_read_u32(parent, "offset", &offset)) {
 162                if (imc_get_mem_addr_nest(parent, pmu_ptr, offset))
 163                        goto free_pmu;
 164        }
 165
 166        /* Function to register IMC pmu */
 167        ret = init_imc_pmu(parent, pmu_ptr, pmu_index);
 168        if (ret) {
 169                pr_err("IMC PMU %s Register failed\n", pmu_ptr->pmu.name);
 170                kfree(pmu_ptr->pmu.name);
 171                if (pmu_ptr->domain == IMC_DOMAIN_NEST)
 172                        kfree(pmu_ptr->mem_info);
 173                kfree(pmu_ptr);
 174                return NULL;
 175        }
 176
 177        return pmu_ptr;
 178
 179free_pmu:
 180        kfree(pmu_ptr);
 181        return NULL;
 182}
 183
 184static void disable_nest_pmu_counters(void)
 185{
 186        int nid, cpu;
 187        const struct cpumask *l_cpumask;
 188
 189        cpus_read_lock();
 190        for_each_node_with_cpus(nid) {
 191                l_cpumask = cpumask_of_node(nid);
 192                cpu = cpumask_first_and(l_cpumask, cpu_online_mask);
 193                if (cpu >= nr_cpu_ids)
 194                        continue;
 195                opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST,
 196                                       get_hard_smp_processor_id(cpu));
 197        }
 198        cpus_read_unlock();
 199}
 200
 201static void disable_core_pmu_counters(void)
 202{
 203        cpumask_t cores_map;
 204        int cpu, rc;
 205
 206        cpus_read_lock();
 207        /* Disable the IMC Core functions */
 208        cores_map = cpu_online_cores_map();
 209        for_each_cpu(cpu, &cores_map) {
 210                rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE,
 211                                            get_hard_smp_processor_id(cpu));
 212                if (rc)
 213                        pr_err("%s: Failed to stop Core (cpu = %d)\n",
 214                                __FUNCTION__, cpu);
 215        }
 216        cpus_read_unlock();
 217}
 218
 219int get_max_nest_dev(void)
 220{
 221        struct device_node *node;
 222        u32 pmu_units = 0, type;
 223
 224        for_each_compatible_node(node, NULL, IMC_DTB_UNIT_COMPAT) {
 225                if (of_property_read_u32(node, "type", &type))
 226                        continue;
 227
 228                if (type == IMC_TYPE_CHIP)
 229                        pmu_units++;
 230        }
 231
 232        return pmu_units;
 233}
 234
 235static int opal_imc_counters_probe(struct platform_device *pdev)
 236{
 237        struct device_node *imc_dev = pdev->dev.of_node;
 238        struct imc_pmu *pmu;
 239        int pmu_count = 0, domain;
 240        bool core_imc_reg = false, thread_imc_reg = false;
 241        u32 type;
 242
 243        /*
 244         * Check whether this is kdump kernel. If yes, force the engines to
 245         * stop and return.
 246         */
 247        if (is_kdump_kernel()) {
 248                disable_nest_pmu_counters();
 249                disable_core_pmu_counters();
 250                return -ENODEV;
 251        }
 252
 253        for_each_compatible_node(imc_dev, NULL, IMC_DTB_UNIT_COMPAT) {
 254                pmu = NULL;
 255                if (of_property_read_u32(imc_dev, "type", &type)) {
 256                        pr_warn("IMC Device without type property\n");
 257                        continue;
 258                }
 259
 260                switch (type) {
 261                case IMC_TYPE_CHIP:
 262                        domain = IMC_DOMAIN_NEST;
 263                        break;
 264                case IMC_TYPE_CORE:
 265                        domain =IMC_DOMAIN_CORE;
 266                        break;
 267                case IMC_TYPE_THREAD:
 268                        domain = IMC_DOMAIN_THREAD;
 269                        break;
 270                case IMC_TYPE_TRACE:
 271                        domain = IMC_DOMAIN_TRACE;
 272                        break;
 273                default:
 274                        pr_warn("IMC Unknown Device type \n");
 275                        domain = -1;
 276                        break;
 277                }
 278
 279                pmu = imc_pmu_create(imc_dev, pmu_count, domain);
 280                if (pmu != NULL) {
 281                        if (domain == IMC_DOMAIN_NEST) {
 282                                if (!imc_debugfs_parent)
 283                                        export_imc_mode_and_cmd(imc_dev, pmu);
 284                                pmu_count++;
 285                        }
 286                        if (domain == IMC_DOMAIN_CORE)
 287                                core_imc_reg = true;
 288                        if (domain == IMC_DOMAIN_THREAD)
 289                                thread_imc_reg = true;
 290                }
 291        }
 292
 293        /* If core imc is not registered, unregister thread-imc */
 294        if (!core_imc_reg && thread_imc_reg)
 295                unregister_thread_imc();
 296
 297        return 0;
 298}
 299
 300static void opal_imc_counters_shutdown(struct platform_device *pdev)
 301{
 302        /*
 303         * Function only stops the engines which is bare minimum.
 304         * TODO: Need to handle proper memory cleanup and pmu
 305         * unregister.
 306         */
 307        disable_nest_pmu_counters();
 308        disable_core_pmu_counters();
 309}
 310
 311static const struct of_device_id opal_imc_match[] = {
 312        { .compatible = IMC_DTB_COMPAT },
 313        {},
 314};
 315
 316static struct platform_driver opal_imc_driver = {
 317        .driver = {
 318                .name = "opal-imc-counters",
 319                .of_match_table = opal_imc_match,
 320        },
 321        .probe = opal_imc_counters_probe,
 322        .shutdown = opal_imc_counters_shutdown,
 323};
 324
 325builtin_platform_driver(opal_imc_driver);
 326