/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Support Intel uncore PerfMon discovery mechanism.
 * Copyright(c) 2021 Intel Corporation.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <asm/msr.h>
#include "uncore.h"
#include "uncore_discovery.h"

static struct rb_root discovery_tables = RB_ROOT;
static int num_discovered_types[UNCORE_ACCESS_MAX];

static int logical_die_id;

static int get_device_die_id(struct pci_dev *dev)
{
        int node = pcibus_to_node(dev->bus);

        /*
         * If the NUMA info is not available, assume that the logical die id is
         * continuous in the order in which the discovery table devices are
         * detected.
         */
        if (node < 0)
                return logical_die_id++;

        return uncore_device_to_die(dev);
}

#define __node_2_type(cur)      \
        rb_entry((cur), struct intel_uncore_discovery_type, node)

static inline int __type_cmp(const void *key, const struct rb_node *b)
{
        const struct intel_uncore_discovery_type *type_b = __node_2_type(b);
        const u16 *type_id = key;

        if (type_b->type > *type_id)
                return -1;
        else if (type_b->type < *type_id)
                return 1;

        return 0;
}

static inline struct intel_uncore_discovery_type *
search_uncore_discovery_type(u16 type_id)
{
        struct rb_node *node = rb_find(&type_id, &discovery_tables, __type_cmp);

        return (node) ? __node_2_type(node) : NULL;
}

static inline bool __type_less(struct rb_node *a, const struct rb_node *b)
{
        return (__node_2_type(a)->type < __node_2_type(b)->type);
}

static struct intel_uncore_discovery_type *
add_uncore_discovery_type(struct uncore_unit_discovery *unit)
{
        struct intel_uncore_discovery_type *type;

        if (unit->access_type >= UNCORE_ACCESS_MAX) {
                pr_warn("Unsupported access type %d\n", unit->access_type);
                return NULL;
        }

        type = kzalloc_obj(struct intel_uncore_discovery_type);
        if (!type)
                return NULL;

        type->units = RB_ROOT;

        type->access_type = unit->access_type;
        num_discovered_types[type->access_type]++;
        type->type = unit->box_type;

        rb_add(&type->node, &discovery_tables, __type_less);

        return type;
}

static struct intel_uncore_discovery_type *
get_uncore_discovery_type(struct uncore_unit_discovery *unit)
{
        struct intel_uncore_discovery_type *type;

        type = search_uncore_discovery_type(unit->box_type);
        if (type)
                return type;

        return add_uncore_discovery_type(unit);
}

static inline int pmu_idx_cmp(const void *key, const struct rb_node *b)
{
        const struct intel_uncore_discovery_unit *unit;
        const unsigned int *id = key;

        unit = rb_entry(b, struct intel_uncore_discovery_unit, node);

        if (unit->pmu_idx > *id)
                return -1;
        else if (unit->pmu_idx < *id)
                return 1;

        return 0;
}

static struct intel_uncore_discovery_unit *
intel_uncore_find_discovery_unit(struct rb_root *units, int die,
                                 unsigned int pmu_idx)
{
        struct intel_uncore_discovery_unit *unit;
        struct rb_node *pos;

        if (!units)
                return NULL;

        pos = rb_find_first(&pmu_idx, units, pmu_idx_cmp);
        if (!pos)
                return NULL;
        unit = rb_entry(pos, struct intel_uncore_discovery_unit, node);

        if (die < 0)
                return unit;

        for (; pos; pos = rb_next(pos)) {
                unit = rb_entry(pos, struct intel_uncore_discovery_unit, node);

                if (unit->pmu_idx != pmu_idx)
                        break;

                if (unit->die == die)
                        return unit;
        }

        return NULL;
}

int intel_uncore_find_discovery_unit_id(struct rb_root *units, int die,
                                        unsigned int pmu_idx)
{
        struct intel_uncore_discovery_unit *unit;

        unit = intel_uncore_find_discovery_unit(units, die, pmu_idx);
        if (unit)
                return unit->id;

        return -1;
}

static inline bool unit_less(struct rb_node *a, const struct rb_node *b)
{
        const struct intel_uncore_discovery_unit *a_node, *b_node;

        a_node = rb_entry(a, struct intel_uncore_discovery_unit, node);
        b_node = rb_entry(b, struct intel_uncore_discovery_unit, node);

        if (a_node->pmu_idx < b_node->pmu_idx)
                return true;
        if (a_node->pmu_idx > b_node->pmu_idx)
                return false;

        if (a_node->die < b_node->die)
                return true;
        if (a_node->die > b_node->die)
                return false;

        return 0;
}

static inline struct intel_uncore_discovery_unit *
uncore_find_unit(struct rb_root *root, unsigned int id)
{
        struct intel_uncore_discovery_unit *unit;
        struct rb_node *node;

        for (node = rb_first(root); node; node = rb_next(node)) {
                unit = rb_entry(node, struct intel_uncore_discovery_unit, node);
                if (unit->id == id)
                        return unit;
        }

        return NULL;
}

void uncore_find_add_unit(struct intel_uncore_discovery_unit *node,
                          struct rb_root *root, u16 *num_units)
{
        struct intel_uncore_discovery_unit *unit = uncore_find_unit(root, node->id);

        if (unit)
                node->pmu_idx = unit->pmu_idx;
        else if (num_units)
                node->pmu_idx = (*num_units)++;

        rb_add(&node->node, root, unit_less);
}

static void
uncore_insert_box_info(struct uncore_unit_discovery *unit,
                       int die)
{
        struct intel_uncore_discovery_unit *node;
        struct intel_uncore_discovery_type *type;

        if (!unit->ctl || !unit->ctl_offset || !unit->ctr_offset) {
                pr_info("Invalid address is detected for uncore type %d box %d, "
                        "Disable the uncore unit.\n",
                        unit->box_type, unit->box_id);
                return;
        }

        node = kzalloc_obj(*node);
        if (!node)
                return;

        node->die = die;
        node->id = unit->box_id;
        node->addr = unit->ctl;

        type = get_uncore_discovery_type(unit);
        if (!type) {
                kfree(node);
                return;
        }

        uncore_find_add_unit(node, &type->units, &type->num_units);

        /* Store generic information for the first box */
        if (type->num_units == 1) {
                type->num_counters = unit->num_regs;
                type->counter_width = unit->bit_width;
                type->ctl_offset = unit->ctl_offset;
                type->ctr_offset = unit->ctr_offset;
        }
}

static bool
uncore_ignore_unit(struct uncore_unit_discovery *unit,
                   struct uncore_discovery_domain *domain)
{
        int i;

        if (!domain || !domain->units_ignore)
                return false;

        for (i = 0; domain->units_ignore[i] != UNCORE_IGNORE_END ; i++) {
                if (unit->box_type == domain->units_ignore[i])
                        return true;
        }

        return false;
}

static int __parse_discovery_table(struct uncore_discovery_domain *domain,
                                   resource_size_t addr, int die, bool *parsed)
{
        struct uncore_global_discovery global;
        struct uncore_unit_discovery unit;
        void __iomem *io_addr;
        unsigned long size;
        int i;

        size = UNCORE_DISCOVERY_GLOBAL_MAP_SIZE;
        io_addr = ioremap(addr, size);
        if (!io_addr)
                return -ENOMEM;

        /* Read Global Discovery State */
        memcpy_fromio(&global, io_addr, sizeof(struct uncore_global_discovery));
        if (uncore_discovery_invalid_unit(global)) {
                pr_info("Invalid Global Discovery State: 0x%llx 0x%llx 0x%llx\n",
                        global.table1, global.ctl, global.table3);
                iounmap(io_addr);
                return -EINVAL;
        }
        iounmap(io_addr);

        size = (1 + global.max_units) * global.stride * 8;
        io_addr = ioremap(addr, size);
        if (!io_addr)
                return -ENOMEM;

        if (domain->global_init && domain->global_init(global.ctl))
                return -ENODEV;

        /* Parsing Unit Discovery State */
        for (i = 0; i < global.max_units; i++) {
                memcpy_fromio(&unit, io_addr + (i + 1) * (global.stride * 8),
                              sizeof(struct uncore_unit_discovery));

                if (uncore_discovery_invalid_unit(unit))
                        continue;

                if (unit.access_type >= UNCORE_ACCESS_MAX)
                        continue;

                if (uncore_ignore_unit(&unit, domain))
                        continue;

                uncore_insert_box_info(&unit, die);
        }

        *parsed = true;
        iounmap(io_addr);
        return 0;
}

static int parse_discovery_table(struct uncore_discovery_domain *domain,
                                 struct pci_dev *dev, int die,
                                 u32 bar_offset, bool *parsed)
{
        resource_size_t addr;
        u32 val;

        pci_read_config_dword(dev, bar_offset, &val);

        if (val & ~PCI_BASE_ADDRESS_MEM_MASK & ~PCI_BASE_ADDRESS_MEM_TYPE_64)
                return -EINVAL;

        addr = (resource_size_t)(val & PCI_BASE_ADDRESS_MEM_MASK);
#ifdef CONFIG_PHYS_ADDR_T_64BIT
        if ((val & PCI_BASE_ADDRESS_MEM_TYPE_MASK) == PCI_BASE_ADDRESS_MEM_TYPE_64) {
                u32 val2;

                pci_read_config_dword(dev, bar_offset + 4, &val2);
                addr |= ((resource_size_t)val2) << 32;
        }
#endif

        return __parse_discovery_table(domain, addr, die, parsed);
}

static bool uncore_discovery_pci(struct uncore_discovery_domain *domain)
{
        u32 device, val, entry_id, bar_offset;
        int die, dvsec = 0, ret = true;
        struct pci_dev *dev = NULL;
        bool parsed = false;

        device = domain->discovery_base;

        /*
         * Start a new search and iterates through the list of
         * the discovery table devices.
         */
        while ((dev = pci_get_device(PCI_VENDOR_ID_INTEL, device, dev)) != NULL) {
                while ((dvsec = pci_find_next_ext_capability(dev, dvsec, UNCORE_EXT_CAP_ID_DISCOVERY))) {
                        pci_read_config_dword(dev, dvsec + UNCORE_DISCOVERY_DVSEC_OFFSET, &val);
                        entry_id = val & UNCORE_DISCOVERY_DVSEC_ID_MASK;
                        if (entry_id != UNCORE_DISCOVERY_DVSEC_ID_PMON)
                                continue;

                        pci_read_config_dword(dev, dvsec + UNCORE_DISCOVERY_DVSEC2_OFFSET, &val);

                        if (val & ~UNCORE_DISCOVERY_DVSEC2_BIR_MASK) {
                                ret = false;
                                goto err;
                        }
                        bar_offset = UNCORE_DISCOVERY_BIR_BASE +
                                     (val & UNCORE_DISCOVERY_DVSEC2_BIR_MASK) * UNCORE_DISCOVERY_BIR_STEP;

                        die = get_device_die_id(dev);
                        if (die < 0)
                                continue;

                        parse_discovery_table(domain, dev, die, bar_offset, &parsed);
                }
        }

        /* None of the discovery tables are available */
        if (!parsed)
                ret = false;
err:
        pci_dev_put(dev);

        return ret;
}

static bool uncore_discovery_msr(struct uncore_discovery_domain *domain)
{
        unsigned long *die_mask;
        bool parsed = false;
        int cpu, die;
        u64 base;

        die_mask = kcalloc(BITS_TO_LONGS(uncore_max_dies()),
                           sizeof(unsigned long), GFP_KERNEL);
        if (!die_mask)
                return false;

        cpus_read_lock();
        for_each_online_cpu(cpu) {
                die = topology_logical_die_id(cpu);
                if (__test_and_set_bit(die, die_mask))
                        continue;

                if (rdmsrq_safe_on_cpu(cpu, domain->discovery_base, &base))
                        continue;

                if (!base)
                        continue;

                __parse_discovery_table(domain, base, die, &parsed);
        }

        cpus_read_unlock();

        kfree(die_mask);
        return parsed;
}

bool uncore_discovery(struct uncore_plat_init *init)
{
        struct uncore_discovery_domain *domain;
        bool ret = false;
        int i;

        for (i = 0; i < UNCORE_DISCOVERY_DOMAINS; i++) {
                domain = &init->domain[i];
                if (domain->discovery_base) {
                        if (!domain->base_is_pci)
                                ret |= uncore_discovery_msr(domain);
                        else
                                ret |= uncore_discovery_pci(domain);
                }
        }

        return ret;
}

void intel_uncore_clear_discovery_tables(void)
{
        struct intel_uncore_discovery_type *type, *next;
        struct intel_uncore_discovery_unit *pos;
        struct rb_node *node;

        rbtree_postorder_for_each_entry_safe(type, next, &discovery_tables, node) {
                while (!RB_EMPTY_ROOT(&type->units)) {
                        node = rb_first(&type->units);
                        pos = rb_entry(node, struct intel_uncore_discovery_unit, node);
                        rb_erase(node, &type->units);
                        kfree(pos);
                }
                kfree(type);
        }
}

DEFINE_UNCORE_FORMAT_ATTR(event, event, "config:0-7");
DEFINE_UNCORE_FORMAT_ATTR(umask, umask, "config:8-15");
DEFINE_UNCORE_FORMAT_ATTR(edge, edge, "config:18");
DEFINE_UNCORE_FORMAT_ATTR(inv, inv, "config:23");
DEFINE_UNCORE_FORMAT_ATTR(thresh, thresh, "config:24-31");

static struct attribute *generic_uncore_formats_attr[] = {
        &format_attr_event.attr,
        &format_attr_umask.attr,
        &format_attr_edge.attr,
        &format_attr_inv.attr,
        &format_attr_thresh.attr,
        NULL,
};

static const struct attribute_group generic_uncore_format_group = {
        .name = "format",
        .attrs = generic_uncore_formats_attr,
};

static u64 intel_generic_uncore_box_ctl(struct intel_uncore_box *box)
{
        struct intel_uncore_discovery_unit *unit;

        unit = intel_uncore_find_discovery_unit(box->pmu->type->boxes,
                                                -1, box->pmu->pmu_idx);
        if (WARN_ON_ONCE(!unit))
                return 0;

        return unit->addr;
}

void intel_generic_uncore_msr_init_box(struct intel_uncore_box *box)
{
        wrmsrq(intel_generic_uncore_box_ctl(box), GENERIC_PMON_BOX_CTL_INT);
}

void intel_generic_uncore_msr_disable_box(struct intel_uncore_box *box)
{
        wrmsrq(intel_generic_uncore_box_ctl(box), GENERIC_PMON_BOX_CTL_FRZ);
}

void intel_generic_uncore_msr_enable_box(struct intel_uncore_box *box)
{
        wrmsrq(intel_generic_uncore_box_ctl(box), 0);
}

static void intel_generic_uncore_msr_enable_event(struct intel_uncore_box *box,
                                            struct perf_event *event)
{
        struct hw_perf_event *hwc = &event->hw;

        wrmsrq(hwc->config_base, hwc->config);
}

static void intel_generic_uncore_msr_disable_event(struct intel_uncore_box *box,
                                             struct perf_event *event)
{
        struct hw_perf_event *hwc = &event->hw;

        wrmsrq(hwc->config_base, 0);
}

static struct intel_uncore_ops generic_uncore_msr_ops = {
        .init_box               = intel_generic_uncore_msr_init_box,
        .disable_box            = intel_generic_uncore_msr_disable_box,
        .enable_box             = intel_generic_uncore_msr_enable_box,
        .disable_event          = intel_generic_uncore_msr_disable_event,
        .enable_event           = intel_generic_uncore_msr_enable_event,
        .read_counter           = uncore_msr_read_counter,
};

bool intel_generic_uncore_assign_hw_event(struct perf_event *event,
                                          struct intel_uncore_box *box)
{
        struct hw_perf_event *hwc = &event->hw;
        u64 box_ctl;

        if (!box->pmu->type->boxes)
                return false;

        if (box->io_addr) {
                hwc->config_base = uncore_pci_event_ctl(box, hwc->idx);
                hwc->event_base  = uncore_pci_perf_ctr(box, hwc->idx);
                return true;
        }

        box_ctl = intel_generic_uncore_box_ctl(box);
        if (!box_ctl)
                return false;

        if (box->pci_dev) {
                box_ctl = UNCORE_DISCOVERY_PCI_BOX_CTRL(box_ctl);
                hwc->config_base = box_ctl + uncore_pci_event_ctl(box, hwc->idx);
                hwc->event_base  = box_ctl + uncore_pci_perf_ctr(box, hwc->idx);
                return true;
        }

        hwc->config_base = box_ctl + box->pmu->type->event_ctl + hwc->idx;
        hwc->event_base  = box_ctl + box->pmu->type->perf_ctr + hwc->idx;

        return true;
}

static inline int intel_pci_uncore_box_ctl(struct intel_uncore_box *box)
{
        return UNCORE_DISCOVERY_PCI_BOX_CTRL(intel_generic_uncore_box_ctl(box));
}

void intel_generic_uncore_pci_init_box(struct intel_uncore_box *box)
{
        struct pci_dev *pdev = box->pci_dev;
        int box_ctl = intel_pci_uncore_box_ctl(box);

        __set_bit(UNCORE_BOX_FLAG_CTL_OFFS8, &box->flags);
        pci_write_config_dword(pdev, box_ctl, GENERIC_PMON_BOX_CTL_INT);
}

void intel_generic_uncore_pci_disable_box(struct intel_uncore_box *box)
{
        struct pci_dev *pdev = box->pci_dev;
        int box_ctl = intel_pci_uncore_box_ctl(box);

        pci_write_config_dword(pdev, box_ctl, GENERIC_PMON_BOX_CTL_FRZ);
}

void intel_generic_uncore_pci_enable_box(struct intel_uncore_box *box)
{
        struct pci_dev *pdev = box->pci_dev;
        int box_ctl = intel_pci_uncore_box_ctl(box);

        pci_write_config_dword(pdev, box_ctl, 0);
}

static void intel_generic_uncore_pci_enable_event(struct intel_uncore_box *box,
                                            struct perf_event *event)
{
        struct pci_dev *pdev = box->pci_dev;
        struct hw_perf_event *hwc = &event->hw;

        pci_write_config_dword(pdev, hwc->config_base, hwc->config);
}

void intel_generic_uncore_pci_disable_event(struct intel_uncore_box *box,
                                            struct perf_event *event)
{
        struct pci_dev *pdev = box->pci_dev;
        struct hw_perf_event *hwc = &event->hw;

        pci_write_config_dword(pdev, hwc->config_base, 0);
}

u64 intel_generic_uncore_pci_read_counter(struct intel_uncore_box *box,
                                          struct perf_event *event)
{
        struct pci_dev *pdev = box->pci_dev;
        struct hw_perf_event *hwc = &event->hw;
        u64 count = 0;

        pci_read_config_dword(pdev, hwc->event_base, (u32 *)&count);
        pci_read_config_dword(pdev, hwc->event_base + 4, (u32 *)&count + 1);

        return count;
}

static struct intel_uncore_ops generic_uncore_pci_ops = {
        .init_box       = intel_generic_uncore_pci_init_box,
        .disable_box    = intel_generic_uncore_pci_disable_box,
        .enable_box     = intel_generic_uncore_pci_enable_box,
        .disable_event  = intel_generic_uncore_pci_disable_event,
        .enable_event   = intel_generic_uncore_pci_enable_event,
        .read_counter   = intel_generic_uncore_pci_read_counter,
};

#define UNCORE_GENERIC_MMIO_SIZE                0x4000

void intel_generic_uncore_mmio_init_box(struct intel_uncore_box *box)
{
        static struct intel_uncore_discovery_unit *unit;
        struct intel_uncore_type *type = box->pmu->type;
        resource_size_t addr;

        unit = intel_uncore_find_discovery_unit(type->boxes, box->dieid, box->pmu->pmu_idx);
        if (!unit) {
                pr_warn("Uncore type %d id %d: Cannot find box control address.\n",
                        type->type_id, box->pmu->pmu_idx);
                return;
        }

        if (!unit->addr) {
                pr_warn("Uncore type %d box %d: Invalid box control address.\n",
                        type->type_id, unit->id);
                return;
        }

        addr = unit->addr;
        box->io_addr = ioremap(addr, type->mmio_map_size);
        if (!box->io_addr) {
                pr_warn("Uncore type %d box %d: ioremap error for 0x%llx.\n",
                        type->type_id, unit->id, (unsigned long long)addr);
                return;
        }

        writel(GENERIC_PMON_BOX_CTL_INT, box->io_addr);
}

void intel_generic_uncore_mmio_disable_box(struct intel_uncore_box *box)
{
        if (!box->io_addr)
                return;

        writel(GENERIC_PMON_BOX_CTL_FRZ, box->io_addr);
}

void intel_generic_uncore_mmio_enable_box(struct intel_uncore_box *box)
{
        if (!box->io_addr)
                return;

        writel(0, box->io_addr);
}

void intel_generic_uncore_mmio_enable_event(struct intel_uncore_box *box,
                                            struct perf_event *event)
{
        struct hw_perf_event *hwc = &event->hw;

        if (!box->io_addr)
                return;

        writel(hwc->config, box->io_addr + hwc->config_base);
}

void intel_generic_uncore_mmio_disable_event(struct intel_uncore_box *box,
                                             struct perf_event *event)
{
        struct hw_perf_event *hwc = &event->hw;

        if (!box->io_addr)
                return;

        writel(0, box->io_addr + hwc->config_base);
}

static struct intel_uncore_ops generic_uncore_mmio_ops = {
        .init_box       = intel_generic_uncore_mmio_init_box,
        .exit_box       = uncore_mmio_exit_box,
        .disable_box    = intel_generic_uncore_mmio_disable_box,
        .enable_box     = intel_generic_uncore_mmio_enable_box,
        .disable_event  = intel_generic_uncore_mmio_disable_event,
        .enable_event   = intel_generic_uncore_mmio_enable_event,
        .read_counter   = uncore_mmio_read_counter,
};

static bool uncore_update_uncore_type(enum uncore_access_type type_id,
                                      struct intel_uncore_type *uncore,
                                      struct intel_uncore_discovery_type *type)
{
        uncore->type_id = type->type;
        uncore->num_counters = type->num_counters;
        uncore->perf_ctr_bits = type->counter_width;
        uncore->perf_ctr = (unsigned int)type->ctr_offset;
        uncore->event_ctl = (unsigned int)type->ctl_offset;
        uncore->boxes = &type->units;
        uncore->num_boxes = type->num_units;

        switch (type_id) {
        case UNCORE_ACCESS_MSR:
                uncore->ops = &generic_uncore_msr_ops;
                break;
        case UNCORE_ACCESS_PCI:
                uncore->ops = &generic_uncore_pci_ops;
                break;
        case UNCORE_ACCESS_MMIO:
                uncore->ops = &generic_uncore_mmio_ops;
                uncore->mmio_map_size = UNCORE_GENERIC_MMIO_SIZE;
                break;
        default:
                return false;
        }

        return true;
}

struct intel_uncore_type **
intel_uncore_generic_init_uncores(enum uncore_access_type type_id, int num_extra)
{
        struct intel_uncore_discovery_type *type;
        struct intel_uncore_type **uncores;
        struct intel_uncore_type *uncore;
        struct rb_node *node;
        int i = 0;

        uncores = kzalloc_objs(struct intel_uncore_type *,
                               num_discovered_types[type_id] + num_extra + 1);
        if (!uncores)
                return empty_uncore;

        for (node = rb_first(&discovery_tables); node; node = rb_next(node)) {
                type = rb_entry(node, struct intel_uncore_discovery_type, node);
                if (type->access_type != type_id)
                        continue;

                uncore = kzalloc_obj(struct intel_uncore_type);
                if (!uncore)
                        break;

                uncore->event_mask = GENERIC_PMON_RAW_EVENT_MASK;
                uncore->format_group = &generic_uncore_format_group;

                if (!uncore_update_uncore_type(type_id, uncore, type)) {
                        kfree(uncore);
                        continue;
                }
                uncores[i++] = uncore;
        }

        return uncores;
}

void intel_uncore_generic_uncore_cpu_init(void)
{
        uncore_msr_uncores = intel_uncore_generic_init_uncores(UNCORE_ACCESS_MSR, 0);
}

int intel_uncore_generic_uncore_pci_init(void)
{
        uncore_pci_uncores = intel_uncore_generic_init_uncores(UNCORE_ACCESS_PCI, 0);

        return 0;
}

void intel_uncore_generic_uncore_mmio_init(void)
{
        uncore_mmio_uncores = intel_uncore_generic_init_uncores(UNCORE_ACCESS_MMIO, 0);
}