/*
 * Copyright 2014 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include <linux/amd-iommu.h>
#include <linux/bsearch.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include "kfd_priv.h"
#include "kfd_device_queue_manager.h"
#include "kfd_pm4_headers.h"

#define MQD_SIZE_ALIGNED 768

static const struct kfd_device_info kaveri_device_info = {
        .asic_family = CHIP_KAVERI,
        .max_pasid_bits = 16,
        /* max num of queues for KV.TODO should be a dynamic value */
        .max_no_of_hqd  = 24,
        .ih_ring_entry_size = 4 * sizeof(uint32_t),
        .event_interrupt_class = &event_interrupt_class_cik,
        .num_of_watch_points = 4,
        .mqd_size_aligned = MQD_SIZE_ALIGNED
};

static const struct kfd_device_info carrizo_device_info = {
        .asic_family = CHIP_CARRIZO,
        .max_pasid_bits = 16,
        /* max num of queues for CZ.TODO should be a dynamic value */
        .max_no_of_hqd  = 24,
        .ih_ring_entry_size = 4 * sizeof(uint32_t),
        .event_interrupt_class = &event_interrupt_class_cik,
        .num_of_watch_points = 4,
        .mqd_size_aligned = MQD_SIZE_ALIGNED
};

struct kfd_deviceid {
        unsigned short did;
        const struct kfd_device_info *device_info;
};

/* Please keep this sorted by increasing device id. */
static const struct kfd_deviceid supported_devices[] = {
        { 0x1304, &kaveri_device_info },        /* Kaveri */
        { 0x1305, &kaveri_device_info },        /* Kaveri */
        { 0x1306, &kaveri_device_info },        /* Kaveri */
        { 0x1307, &kaveri_device_info },        /* Kaveri */
        { 0x1309, &kaveri_device_info },        /* Kaveri */
        { 0x130A, &kaveri_device_info },        /* Kaveri */
        { 0x130B, &kaveri_device_info },        /* Kaveri */
        { 0x130C, &kaveri_device_info },        /* Kaveri */
        { 0x130D, &kaveri_device_info },        /* Kaveri */
        { 0x130E, &kaveri_device_info },        /* Kaveri */
        { 0x130F, &kaveri_device_info },        /* Kaveri */
        { 0x1310, &kaveri_device_info },        /* Kaveri */
        { 0x1311, &kaveri_device_info },        /* Kaveri */
        { 0x1312, &kaveri_device_info },        /* Kaveri */
        { 0x1313, &kaveri_device_info },        /* Kaveri */
        { 0x1315, &kaveri_device_info },        /* Kaveri */
        { 0x1316, &kaveri_device_info },        /* Kaveri */
        { 0x1317, &kaveri_device_info },        /* Kaveri */
        { 0x1318, &kaveri_device_info },        /* Kaveri */
        { 0x131B, &kaveri_device_info },        /* Kaveri */
        { 0x131C, &kaveri_device_info },        /* Kaveri */
        { 0x131D, &kaveri_device_info },        /* Kaveri */
        { 0x9870, &carrizo_device_info },       /* Carrizo */
        { 0x9874, &carrizo_device_info },       /* Carrizo */
        { 0x9875, &carrizo_device_info },       /* Carrizo */
        { 0x9876, &carrizo_device_info },       /* Carrizo */
        { 0x9877, &carrizo_device_info }        /* Carrizo */
};

static int kfd_gtt_sa_init(struct kfd_dev *kfd, unsigned int buf_size,
                                unsigned int chunk_size);
static void kfd_gtt_sa_fini(struct kfd_dev *kfd);

static const struct kfd_device_info *lookup_device_info(unsigned short did)
{
        size_t i;

        for (i = 0; i < ARRAY_SIZE(supported_devices); i++) {
                if (supported_devices[i].did == did) {
                        BUG_ON(supported_devices[i].device_info == NULL);
                        return supported_devices[i].device_info;
                }
        }

        return NULL;
}

struct kfd_dev *kgd2kfd_probe(struct kgd_dev *kgd,
        struct pci_dev *pdev, const struct kfd2kgd_calls *f2g)
{
        struct kfd_dev *kfd;

        const struct kfd_device_info *device_info =
                                        lookup_device_info(pdev->device);

        if (!device_info)
                return NULL;

        kfd = kzalloc(sizeof(*kfd), GFP_KERNEL);
        if (!kfd)
                return NULL;

        kfd->kgd = kgd;
        kfd->device_info = device_info;
        kfd->pdev = pdev;
        kfd->init_complete = false;
        kfd->kfd2kgd = f2g;

        mutex_init(&kfd->doorbell_mutex);
        memset(&kfd->doorbell_available_index, 0,
                sizeof(kfd->doorbell_available_index));

        return kfd;
}

static bool device_iommu_pasid_init(struct kfd_dev *kfd)
{
        const u32 required_iommu_flags = AMD_IOMMU_DEVICE_FLAG_ATS_SUP |
                                        AMD_IOMMU_DEVICE_FLAG_PRI_SUP |
                                        AMD_IOMMU_DEVICE_FLAG_PASID_SUP;

        struct amd_iommu_device_info iommu_info;
        unsigned int pasid_limit;
        int err;

        err = amd_iommu_device_info(kfd->pdev, &iommu_info);
        if (err < 0) {
                dev_err(kfd_device,
                        "error getting iommu info. is the iommu enabled?\n");
                return false;
        }

        if ((iommu_info.flags & required_iommu_flags) != required_iommu_flags) {
                dev_err(kfd_device, "error required iommu flags ats(%i), pri(%i), pasid(%i)\n",
                       (iommu_info.flags & AMD_IOMMU_DEVICE_FLAG_ATS_SUP) != 0,
                       (iommu_info.flags & AMD_IOMMU_DEVICE_FLAG_PRI_SUP) != 0,
                       (iommu_info.flags & AMD_IOMMU_DEVICE_FLAG_PASID_SUP) != 0);
                return false;
        }

        pasid_limit = min_t(unsigned int,
                        (unsigned int)1 << kfd->device_info->max_pasid_bits,
                        iommu_info.max_pasids);
        /*
         * last pasid is used for kernel queues doorbells
         * in the future the last pasid might be used for a kernel thread.
         */
        pasid_limit = min_t(unsigned int,
                                pasid_limit,
                                kfd->doorbell_process_limit - 1);

        err = amd_iommu_init_device(kfd->pdev, pasid_limit);
        if (err < 0) {
                dev_err(kfd_device, "error initializing iommu device\n");
                return false;
        }

        if (!kfd_set_pasid_limit(pasid_limit)) {
                dev_err(kfd_device, "error setting pasid limit\n");
                amd_iommu_free_device(kfd->pdev);
                return false;
        }

        return true;
}

static void iommu_pasid_shutdown_callback(struct pci_dev *pdev, int pasid)
{
        struct kfd_dev *dev = kfd_device_by_pci_dev(pdev);

        if (dev)
                kfd_unbind_process_from_device(dev, pasid);
}

/*
 * This function called by IOMMU driver on PPR failure
 */
static int iommu_invalid_ppr_cb(struct pci_dev *pdev, int pasid,
                unsigned long address, u16 flags)
{
        struct kfd_dev *dev;

        dev_warn(kfd_device,
                        "Invalid PPR device %x:%x.%x pasid %d address 0x%lX flags 0x%X",
                        PCI_BUS_NUM(pdev->devfn),
                        PCI_SLOT(pdev->devfn),
                        PCI_FUNC(pdev->devfn),
                        pasid,
                        address,
                        flags);

        dev = kfd_device_by_pci_dev(pdev);
        BUG_ON(dev == NULL);

        kfd_signal_iommu_event(dev, pasid, address,
                        flags & PPR_FAULT_WRITE, flags & PPR_FAULT_EXEC);

        return AMD_IOMMU_INV_PRI_RSP_INVALID;
}

bool kgd2kfd_device_init(struct kfd_dev *kfd,
                         const struct kgd2kfd_shared_resources *gpu_resources)
{
        unsigned int size;

        kfd->shared_resources = *gpu_resources;

        /* calculate max size of mqds needed for queues */
        size = max_num_of_queues_per_device *
                        kfd->device_info->mqd_size_aligned;

        /*
         * calculate max size of runlist packet.
         * There can be only 2 packets at once
         */
        size += (KFD_MAX_NUM_OF_PROCESSES * sizeof(struct pm4_map_process) +
                max_num_of_queues_per_device *
                sizeof(struct pm4_map_queues) + sizeof(struct pm4_runlist)) * 2;

        /* Add size of HIQ & DIQ */
        size += KFD_KERNEL_QUEUE_SIZE * 2;

        /* add another 512KB for all other allocations on gart (HPD, fences) */
        size += 512 * 1024;

        if (kfd->kfd2kgd->init_gtt_mem_allocation(
                        kfd->kgd, size, &kfd->gtt_mem,
                        &kfd->gtt_start_gpu_addr, &kfd->gtt_start_cpu_ptr)){
                dev_err(kfd_device,
                        "Could not allocate %d bytes for device (%x:%x)\n",
                        size, kfd->pdev->vendor, kfd->pdev->device);
                goto out;
        }

        dev_info(kfd_device,
                "Allocated %d bytes on gart for device(%x:%x)\n",
                size, kfd->pdev->vendor, kfd->pdev->device);

        /* Initialize GTT sa with 512 byte chunk size */
        if (kfd_gtt_sa_init(kfd, size, 512) != 0) {
                dev_err(kfd_device,
                        "Error initializing gtt sub-allocator\n");
                goto kfd_gtt_sa_init_error;
        }

        kfd_doorbell_init(kfd);

        if (kfd_topology_add_device(kfd) != 0) {
                dev_err(kfd_device,
                        "Error adding device (%x:%x) to topology\n",
                        kfd->pdev->vendor, kfd->pdev->device);
                goto kfd_topology_add_device_error;
        }

        if (kfd_interrupt_init(kfd)) {
                dev_err(kfd_device,
                        "Error initializing interrupts for device (%x:%x)\n",
                        kfd->pdev->vendor, kfd->pdev->device);
                goto kfd_interrupt_error;
        }

        if (!device_iommu_pasid_init(kfd)) {
                dev_err(kfd_device,
                        "Error initializing iommuv2 for device (%x:%x)\n",
                        kfd->pdev->vendor, kfd->pdev->device);
                goto device_iommu_pasid_error;
        }
        amd_iommu_set_invalidate_ctx_cb(kfd->pdev,
                                                iommu_pasid_shutdown_callback);
        amd_iommu_set_invalid_ppr_cb(kfd->pdev, iommu_invalid_ppr_cb);

        kfd->dqm = device_queue_manager_init(kfd);
        if (!kfd->dqm) {
                dev_err(kfd_device,
                        "Error initializing queue manager for device (%x:%x)\n",
                        kfd->pdev->vendor, kfd->pdev->device);
                goto device_queue_manager_error;
        }

        if (kfd->dqm->ops.start(kfd->dqm) != 0) {
                dev_err(kfd_device,
                        "Error starting queuen manager for device (%x:%x)\n",
                        kfd->pdev->vendor, kfd->pdev->device);
                goto dqm_start_error;
        }

        kfd->dbgmgr = NULL;

        kfd->init_complete = true;
        dev_info(kfd_device, "added device (%x:%x)\n", kfd->pdev->vendor,
                 kfd->pdev->device);

        pr_debug("kfd: Starting kfd with the following scheduling policy %d\n",
                sched_policy);

        goto out;

dqm_start_error:
        device_queue_manager_uninit(kfd->dqm);
device_queue_manager_error:
        amd_iommu_free_device(kfd->pdev);
device_iommu_pasid_error:
        kfd_interrupt_exit(kfd);
kfd_interrupt_error:
        kfd_topology_remove_device(kfd);
kfd_topology_add_device_error:
        kfd_gtt_sa_fini(kfd);
kfd_gtt_sa_init_error:
        kfd->kfd2kgd->free_gtt_mem(kfd->kgd, kfd->gtt_mem);
        dev_err(kfd_device,
                "device (%x:%x) NOT added due to errors\n",
                kfd->pdev->vendor, kfd->pdev->device);
out:
        return kfd->init_complete;
}

void kgd2kfd_device_exit(struct kfd_dev *kfd)
{
        if (kfd->init_complete) {
                device_queue_manager_uninit(kfd->dqm);
                amd_iommu_free_device(kfd->pdev);
                kfd_interrupt_exit(kfd);
                kfd_topology_remove_device(kfd);
                kfd_gtt_sa_fini(kfd);
                kfd->kfd2kgd->free_gtt_mem(kfd->kgd, kfd->gtt_mem);
        }

        kfree(kfd);
}

void kgd2kfd_suspend(struct kfd_dev *kfd)
{
        BUG_ON(kfd == NULL);

        if (kfd->init_complete) {
                kfd->dqm->ops.stop(kfd->dqm);
                amd_iommu_set_invalidate_ctx_cb(kfd->pdev, NULL);
                amd_iommu_set_invalid_ppr_cb(kfd->pdev, NULL);
                amd_iommu_free_device(kfd->pdev);
        }
}

int kgd2kfd_resume(struct kfd_dev *kfd)
{
        unsigned int pasid_limit;
        int err;

        BUG_ON(kfd == NULL);

        pasid_limit = kfd_get_pasid_limit();

        if (kfd->init_complete) {
                err = amd_iommu_init_device(kfd->pdev, pasid_limit);
                if (err < 0)
                        return -ENXIO;
                amd_iommu_set_invalidate_ctx_cb(kfd->pdev,
                                                iommu_pasid_shutdown_callback);
                amd_iommu_set_invalid_ppr_cb(kfd->pdev, iommu_invalid_ppr_cb);
                kfd->dqm->ops.start(kfd->dqm);
        }

        return 0;
}

/* This is called directly from KGD at ISR. */
void kgd2kfd_interrupt(struct kfd_dev *kfd, const void *ih_ring_entry)
{
        if (!kfd->init_complete)
                return;

        spin_lock(&kfd->interrupt_lock);

        if (kfd->interrupts_active
            && interrupt_is_wanted(kfd, ih_ring_entry)
            && enqueue_ih_ring_entry(kfd, ih_ring_entry))
                schedule_work(&kfd->interrupt_work);

        spin_unlock(&kfd->interrupt_lock);
}

static int kfd_gtt_sa_init(struct kfd_dev *kfd, unsigned int buf_size,
                                unsigned int chunk_size)
{
        unsigned int num_of_bits;

        BUG_ON(!kfd);
        BUG_ON(!kfd->gtt_mem);
        BUG_ON(buf_size < chunk_size);
        BUG_ON(buf_size == 0);
        BUG_ON(chunk_size == 0);

        kfd->gtt_sa_chunk_size = chunk_size;
        kfd->gtt_sa_num_of_chunks = buf_size / chunk_size;

        num_of_bits = kfd->gtt_sa_num_of_chunks / BITS_PER_BYTE;
        BUG_ON(num_of_bits == 0);

        kfd->gtt_sa_bitmap = kzalloc(num_of_bits, GFP_KERNEL);

        if (!kfd->gtt_sa_bitmap)
                return -ENOMEM;

        pr_debug("kfd: gtt_sa_num_of_chunks = %d, gtt_sa_bitmap = %p\n",
                        kfd->gtt_sa_num_of_chunks, kfd->gtt_sa_bitmap);

        mutex_init(&kfd->gtt_sa_lock);

        return 0;

}

static void kfd_gtt_sa_fini(struct kfd_dev *kfd)
{
        mutex_destroy(&kfd->gtt_sa_lock);
        kfree(kfd->gtt_sa_bitmap);
}

static inline uint64_t kfd_gtt_sa_calc_gpu_addr(uint64_t start_addr,
                                                unsigned int bit_num,
                                                unsigned int chunk_size)
{
        return start_addr + bit_num * chunk_size;
}

static inline uint32_t *kfd_gtt_sa_calc_cpu_addr(void *start_addr,
                                                unsigned int bit_num,
                                                unsigned int chunk_size)
{
        return (uint32_t *) ((uint64_t) start_addr + bit_num * chunk_size);
}

int kfd_gtt_sa_allocate(struct kfd_dev *kfd, unsigned int size,
                        struct kfd_mem_obj **mem_obj)
{
        unsigned int found, start_search, cur_size;

        BUG_ON(!kfd);

        if (size == 0)
                return -EINVAL;

        if (size > kfd->gtt_sa_num_of_chunks * kfd->gtt_sa_chunk_size)
                return -ENOMEM;

        *mem_obj = kmalloc(sizeof(struct kfd_mem_obj), GFP_KERNEL);
        if ((*mem_obj) == NULL)
                return -ENOMEM;

        pr_debug("kfd: allocated mem_obj = %p for size = %d\n", *mem_obj, size);

        start_search = 0;

        mutex_lock(&kfd->gtt_sa_lock);

kfd_gtt_restart_search:
        /* Find the first chunk that is free */
        found = find_next_zero_bit(kfd->gtt_sa_bitmap,
                                        kfd->gtt_sa_num_of_chunks,
                                        start_search);

        pr_debug("kfd: found = %d\n", found);

        /* If there wasn't any free chunk, bail out */
        if (found == kfd->gtt_sa_num_of_chunks)
                goto kfd_gtt_no_free_chunk;

        /* Update fields of mem_obj */
        (*mem_obj)->range_start = found;
        (*mem_obj)->range_end = found;
        (*mem_obj)->gpu_addr = kfd_gtt_sa_calc_gpu_addr(
                                        kfd->gtt_start_gpu_addr,
                                        found,
                                        kfd->gtt_sa_chunk_size);
        (*mem_obj)->cpu_ptr = kfd_gtt_sa_calc_cpu_addr(
                                        kfd->gtt_start_cpu_ptr,
                                        found,
                                        kfd->gtt_sa_chunk_size);

        pr_debug("kfd: gpu_addr = %p, cpu_addr = %p\n",
                        (uint64_t *) (*mem_obj)->gpu_addr, (*mem_obj)->cpu_ptr);

        /* If we need only one chunk, mark it as allocated and get out */
        if (size <= kfd->gtt_sa_chunk_size) {
                pr_debug("kfd: single bit\n");
                set_bit(found, kfd->gtt_sa_bitmap);
                goto kfd_gtt_out;
        }

        /* Otherwise, try to see if we have enough contiguous chunks */
        cur_size = size - kfd->gtt_sa_chunk_size;
        do {
                (*mem_obj)->range_end =
                        find_next_zero_bit(kfd->gtt_sa_bitmap,
                                        kfd->gtt_sa_num_of_chunks, ++found);
                /*
                 * If next free chunk is not contiguous than we need to
                 * restart our search from the last free chunk we found (which
                 * wasn't contiguous to the previous ones
                 */
                if ((*mem_obj)->range_end != found) {
                        start_search = found;
                        goto kfd_gtt_restart_search;
                }

                /*
                 * If we reached end of buffer, bail out with error
                 */
                if (found == kfd->gtt_sa_num_of_chunks)
                        goto kfd_gtt_no_free_chunk;

                /* Check if we don't need another chunk */
                if (cur_size <= kfd->gtt_sa_chunk_size)
                        cur_size = 0;
                else
                        cur_size -= kfd->gtt_sa_chunk_size;

        } while (cur_size > 0);

        pr_debug("kfd: range_start = %d, range_end = %d\n",
                (*mem_obj)->range_start, (*mem_obj)->range_end);

        /* Mark the chunks as allocated */
        for (found = (*mem_obj)->range_start;
                found <= (*mem_obj)->range_end;
                found++)
                set_bit(found, kfd->gtt_sa_bitmap);

kfd_gtt_out:
        mutex_unlock(&kfd->gtt_sa_lock);
        return 0;

kfd_gtt_no_free_chunk:
        pr_debug("kfd: allocation failed with mem_obj = %p\n", mem_obj);
        mutex_unlock(&kfd->gtt_sa_lock);
        kfree(mem_obj);
        return -ENOMEM;
}

int kfd_gtt_sa_free(struct kfd_dev *kfd, struct kfd_mem_obj *mem_obj)
{
        unsigned int bit;

        BUG_ON(!kfd);

        /* Act like kfree when trying to free a NULL object */
        if (!mem_obj)
                return 0;

        pr_debug("kfd: free mem_obj = %p, range_start = %d, range_end = %d\n",
                        mem_obj, mem_obj->range_start, mem_obj->range_end);

        mutex_lock(&kfd->gtt_sa_lock);

        /* Mark the chunks as free */
        for (bit = mem_obj->range_start;
                bit <= mem_obj->range_end;
                bit++)
                clear_bit(bit, kfd->gtt_sa_bitmap);

        mutex_unlock(&kfd->gtt_sa_lock);

        kfree(mem_obj);
        return 0;
}