/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
/* Copyright (c) 2021, Microsoft Corporation. */

#ifndef _GDMA_H
#define _GDMA_H

#include <linux/dma-mapping.h>
#include <linux/netdevice.h>

#include "shm_channel.h"

/* Structures labeled with "HW DATA" are exchanged with the hardware. All of
 * them are naturally aligned and hence don't need __packed.
 */

enum gdma_request_type {
        GDMA_VERIFY_VF_DRIVER_VERSION   = 1,
        GDMA_QUERY_MAX_RESOURCES        = 2,
        GDMA_LIST_DEVICES               = 3,
        GDMA_REGISTER_DEVICE            = 4,
        GDMA_DEREGISTER_DEVICE          = 5,
        GDMA_GENERATE_TEST_EQE          = 10,
        GDMA_CREATE_QUEUE               = 12,
        GDMA_DISABLE_QUEUE              = 13,
        GDMA_CREATE_DMA_REGION          = 25,
        GDMA_DMA_REGION_ADD_PAGES       = 26,
        GDMA_DESTROY_DMA_REGION         = 27,
};

enum gdma_queue_type {
        GDMA_INVALID_QUEUE,
        GDMA_SQ,
        GDMA_RQ,
        GDMA_CQ,
        GDMA_EQ,
};

enum gdma_work_request_flags {
        GDMA_WR_NONE                    = 0,
        GDMA_WR_OOB_IN_SGL              = BIT(0),
        GDMA_WR_PAD_BY_SGE0             = BIT(1),
};

enum gdma_eqe_type {
        GDMA_EQE_COMPLETION             = 3,
        GDMA_EQE_TEST_EVENT             = 64,
        GDMA_EQE_HWC_INIT_EQ_ID_DB      = 129,
        GDMA_EQE_HWC_INIT_DATA          = 130,
        GDMA_EQE_HWC_INIT_DONE          = 131,
};

enum {
        GDMA_DEVICE_NONE        = 0,
        GDMA_DEVICE_HWC         = 1,
        GDMA_DEVICE_MANA        = 2,
};

struct gdma_resource {
        /* Protect the bitmap */
        spinlock_t lock;

        /* The bitmap size in bits. */
        u32 size;

        /* The bitmap tracks the resources. */
        unsigned long *map;
};

union gdma_doorbell_entry {
        u64     as_uint64;

        struct {
                u64 id          : 24;
                u64 reserved    : 8;
                u64 tail_ptr    : 31;
                u64 arm         : 1;
        } cq;

        struct {
                u64 id          : 24;
                u64 wqe_cnt     : 8;
                u64 tail_ptr    : 32;
        } rq;

        struct {
                u64 id          : 24;
                u64 reserved    : 8;
                u64 tail_ptr    : 32;
        } sq;

        struct {
                u64 id          : 16;
                u64 reserved    : 16;
                u64 tail_ptr    : 31;
                u64 arm         : 1;
        } eq;
}; /* HW DATA */

struct gdma_msg_hdr {
        u32 hdr_type;
        u32 msg_type;
        u16 msg_version;
        u16 hwc_msg_id;
        u32 msg_size;
}; /* HW DATA */

struct gdma_dev_id {
        union {
                struct {
                        u16 type;
                        u16 instance;
                };

                u32 as_uint32;
        };
}; /* HW DATA */

struct gdma_req_hdr {
        struct gdma_msg_hdr req;
        struct gdma_msg_hdr resp; /* The expected response */
        struct gdma_dev_id dev_id;
        u32 activity_id;
}; /* HW DATA */

struct gdma_resp_hdr {
        struct gdma_msg_hdr response;
        struct gdma_dev_id dev_id;
        u32 activity_id;
        u32 status;
        u32 reserved;
}; /* HW DATA */

struct gdma_general_req {
        struct gdma_req_hdr hdr;
}; /* HW DATA */

#define GDMA_MESSAGE_V1 1

struct gdma_general_resp {
        struct gdma_resp_hdr hdr;
}; /* HW DATA */

#define GDMA_STANDARD_HEADER_TYPE 0

static inline void mana_gd_init_req_hdr(struct gdma_req_hdr *hdr, u32 code,
                                        u32 req_size, u32 resp_size)
{
        hdr->req.hdr_type = GDMA_STANDARD_HEADER_TYPE;
        hdr->req.msg_type = code;
        hdr->req.msg_version = GDMA_MESSAGE_V1;
        hdr->req.msg_size = req_size;

        hdr->resp.hdr_type = GDMA_STANDARD_HEADER_TYPE;
        hdr->resp.msg_type = code;
        hdr->resp.msg_version = GDMA_MESSAGE_V1;
        hdr->resp.msg_size = resp_size;
}

/* The 16-byte struct is part of the GDMA work queue entry (WQE). */
struct gdma_sge {
        u64 address;
        u32 mem_key;
        u32 size;
}; /* HW DATA */

struct gdma_wqe_request {
        struct gdma_sge *sgl;
        u32 num_sge;

        u32 inline_oob_size;
        const void *inline_oob_data;

        u32 flags;
        u32 client_data_unit;
};

enum gdma_page_type {
        GDMA_PAGE_TYPE_4K,
};

#define GDMA_INVALID_DMA_REGION 0

struct gdma_mem_info {
        struct device *dev;

        dma_addr_t dma_handle;
        void *virt_addr;
        u64 length;

        /* Allocated by the PF driver */
        u64 gdma_region;
};

#define REGISTER_ATB_MST_MKEY_LOWER_SIZE 8

struct gdma_dev {
        struct gdma_context *gdma_context;

        struct gdma_dev_id dev_id;

        u32 pdid;
        u32 doorbell;
        u32 gpa_mkey;

        /* GDMA driver specific pointer */
        void *driver_data;
};

#define MINIMUM_SUPPORTED_PAGE_SIZE PAGE_SIZE

#define GDMA_CQE_SIZE 64
#define GDMA_EQE_SIZE 16
#define GDMA_MAX_SQE_SIZE 512
#define GDMA_MAX_RQE_SIZE 256

#define GDMA_COMP_DATA_SIZE 0x3C

#define GDMA_EVENT_DATA_SIZE 0xC

/* The WQE size must be a multiple of the Basic Unit, which is 32 bytes. */
#define GDMA_WQE_BU_SIZE 32

#define INVALID_PDID            UINT_MAX
#define INVALID_DOORBELL        UINT_MAX
#define INVALID_MEM_KEY         UINT_MAX
#define INVALID_QUEUE_ID        UINT_MAX
#define INVALID_PCI_MSIX_INDEX  UINT_MAX

struct gdma_comp {
        u32 cqe_data[GDMA_COMP_DATA_SIZE / 4];
        u32 wq_num;
        bool is_sq;
};

struct gdma_event {
        u32 details[GDMA_EVENT_DATA_SIZE / 4];
        u8  type;
};

struct gdma_queue;

#define CQE_POLLING_BUFFER 512
struct mana_eq {
        struct gdma_queue *eq;
        struct gdma_comp cqe_poll[CQE_POLLING_BUFFER];
};

typedef void gdma_eq_callback(void *context, struct gdma_queue *q,
                              struct gdma_event *e);

typedef void gdma_cq_callback(void *context, struct gdma_queue *q);

/* The 'head' is the producer index. For SQ/RQ, when the driver posts a WQE
 * (Note: the WQE size must be a multiple of the 32-byte Basic Unit), the
 * driver increases the 'head' in BUs rather than in bytes, and notifies
 * the HW of the updated head. For EQ/CQ, the driver uses the 'head' to track
 * the HW head, and increases the 'head' by 1 for every processed EQE/CQE.
 *
 * The 'tail' is the consumer index for SQ/RQ. After the CQE of the SQ/RQ is
 * processed, the driver increases the 'tail' to indicate that WQEs have
 * been consumed by the HW, so the driver can post new WQEs into the SQ/RQ.
 *
 * The driver doesn't use the 'tail' for EQ/CQ, because the driver ensures
 * that the EQ/CQ is big enough so they can't overflow, and the driver uses
 * the owner bits mechanism to detect if the queue has become empty.
 */
struct gdma_queue {
        struct gdma_dev *gdma_dev;

        enum gdma_queue_type type;
        u32 id;

        struct gdma_mem_info mem_info;

        void *queue_mem_ptr;
        u32 queue_size;

        bool monitor_avl_buf;

        u32 head;
        u32 tail;

        /* Extra fields specific to EQ/CQ. */
        union {
                struct {
                        bool disable_needed;

                        gdma_eq_callback *callback;
                        void *context;

                        unsigned int msix_index;

                        u32 log2_throttle_limit;

                        /* NAPI data */
                        struct napi_struct napi;
                        int work_done;
                        int budget;
                } eq;

                struct {
                        gdma_cq_callback *callback;
                        void *context;

                        struct gdma_queue *parent; /* For CQ/EQ relationship */
                } cq;
        };
};

struct gdma_queue_spec {
        enum gdma_queue_type type;
        bool monitor_avl_buf;
        unsigned int queue_size;

        /* Extra fields specific to EQ/CQ. */
        union {
                struct {
                        gdma_eq_callback *callback;
                        void *context;

                        unsigned long log2_throttle_limit;

                        /* Only used by the MANA device. */
                        struct net_device *ndev;
                } eq;

                struct {
                        gdma_cq_callback *callback;
                        void *context;

                        struct gdma_queue *parent_eq;

                } cq;
        };
};

struct gdma_irq_context {
        void (*handler)(void *arg);
        void *arg;
};

struct gdma_context {
        struct device           *dev;

        /* Per-vPort max number of queues */
        unsigned int            max_num_queues;
        unsigned int            max_num_msix;
        unsigned int            num_msix_usable;
        struct gdma_resource    msix_resource;
        struct gdma_irq_context *irq_contexts;

        /* This maps a CQ index to the queue structure. */
        unsigned int            max_num_cqs;
        struct gdma_queue       **cq_table;

        /* Protect eq_test_event and test_event_eq_id  */
        struct mutex            eq_test_event_mutex;
        struct completion       eq_test_event;
        u32                     test_event_eq_id;

        void __iomem            *bar0_va;
        void __iomem            *shm_base;
        void __iomem            *db_page_base;
        u32 db_page_size;

        /* Shared memory chanenl (used to bootstrap HWC) */
        struct shm_channel      shm_channel;

        /* Hardware communication channel (HWC) */
        struct gdma_dev         hwc;

        /* Azure network adapter */
        struct gdma_dev         mana;
};

#define MAX_NUM_GDMA_DEVICES    4

static inline bool mana_gd_is_mana(struct gdma_dev *gd)
{
        return gd->dev_id.type == GDMA_DEVICE_MANA;
}

static inline bool mana_gd_is_hwc(struct gdma_dev *gd)
{
        return gd->dev_id.type == GDMA_DEVICE_HWC;
}

u8 *mana_gd_get_wqe_ptr(const struct gdma_queue *wq, u32 wqe_offset);
u32 mana_gd_wq_avail_space(struct gdma_queue *wq);

int mana_gd_test_eq(struct gdma_context *gc, struct gdma_queue *eq);

int mana_gd_create_hwc_queue(struct gdma_dev *gd,
                             const struct gdma_queue_spec *spec,
                             struct gdma_queue **queue_ptr);

int mana_gd_create_mana_eq(struct gdma_dev *gd,
                           const struct gdma_queue_spec *spec,
                           struct gdma_queue **queue_ptr);

int mana_gd_create_mana_wq_cq(struct gdma_dev *gd,
                              const struct gdma_queue_spec *spec,
                              struct gdma_queue **queue_ptr);

void mana_gd_destroy_queue(struct gdma_context *gc, struct gdma_queue *queue);

int mana_gd_poll_cq(struct gdma_queue *cq, struct gdma_comp *comp, int num_cqe);

void mana_gd_arm_cq(struct gdma_queue *cq);

struct gdma_wqe {
        u32 reserved    :24;
        u32 last_vbytes :8;

        union {
                u32 flags;

                struct {
                        u32 num_sge             :8;
                        u32 inline_oob_size_div4:3;
                        u32 client_oob_in_sgl   :1;
                        u32 reserved1           :4;
                        u32 client_data_unit    :14;
                        u32 reserved2           :2;
                };
        };
}; /* HW DATA */

#define INLINE_OOB_SMALL_SIZE 8
#define INLINE_OOB_LARGE_SIZE 24

#define MAX_TX_WQE_SIZE 512
#define MAX_RX_WQE_SIZE 256

struct gdma_cqe {
        u32 cqe_data[GDMA_COMP_DATA_SIZE / 4];

        union {
                u32 as_uint32;

                struct {
                        u32 wq_num      : 24;
                        u32 is_sq       : 1;
                        u32 reserved    : 4;
                        u32 owner_bits  : 3;
                };
        } cqe_info;
}; /* HW DATA */

#define GDMA_CQE_OWNER_BITS 3

#define GDMA_CQE_OWNER_MASK ((1 << GDMA_CQE_OWNER_BITS) - 1)

#define SET_ARM_BIT 1

#define GDMA_EQE_OWNER_BITS 3

union gdma_eqe_info {
        u32 as_uint32;

        struct {
                u32 type        : 8;
                u32 reserved1   : 8;
                u32 client_id   : 2;
                u32 reserved2   : 11;
                u32 owner_bits  : 3;
        };
}; /* HW DATA */

#define GDMA_EQE_OWNER_MASK ((1 << GDMA_EQE_OWNER_BITS) - 1)
#define INITIALIZED_OWNER_BIT(log2_num_entries) (1UL << (log2_num_entries))

struct gdma_eqe {
        u32 details[GDMA_EVENT_DATA_SIZE / 4];
        u32 eqe_info;
}; /* HW DATA */

#define GDMA_REG_DB_PAGE_OFFSET 8
#define GDMA_REG_DB_PAGE_SIZE   0x10
#define GDMA_REG_SHM_OFFSET     0x18

struct gdma_posted_wqe_info {
        u32 wqe_size_in_bu;
};

/* GDMA_GENERATE_TEST_EQE */
struct gdma_generate_test_event_req {
        struct gdma_req_hdr hdr;
        u32 queue_index;
}; /* HW DATA */

/* GDMA_VERIFY_VF_DRIVER_VERSION */
enum {
        GDMA_PROTOCOL_V1        = 1,
        GDMA_PROTOCOL_FIRST     = GDMA_PROTOCOL_V1,
        GDMA_PROTOCOL_LAST      = GDMA_PROTOCOL_V1,
};

struct gdma_verify_ver_req {
        struct gdma_req_hdr hdr;

        /* Mandatory fields required for protocol establishment */
        u64 protocol_ver_min;
        u64 protocol_ver_max;
        u64 drv_cap_flags1;
        u64 drv_cap_flags2;
        u64 drv_cap_flags3;
        u64 drv_cap_flags4;

        /* Advisory fields */
        u64 drv_ver;
        u32 os_type; /* Linux = 0x10; Windows = 0x20; Other = 0x30 */
        u32 reserved;
        u32 os_ver_major;
        u32 os_ver_minor;
        u32 os_ver_build;
        u32 os_ver_platform;
        u64 reserved_2;
        u8 os_ver_str1[128];
        u8 os_ver_str2[128];
        u8 os_ver_str3[128];
        u8 os_ver_str4[128];
}; /* HW DATA */

struct gdma_verify_ver_resp {
        struct gdma_resp_hdr hdr;
        u64 gdma_protocol_ver;
        u64 pf_cap_flags1;
        u64 pf_cap_flags2;
        u64 pf_cap_flags3;
        u64 pf_cap_flags4;
}; /* HW DATA */

/* GDMA_QUERY_MAX_RESOURCES */
struct gdma_query_max_resources_resp {
        struct gdma_resp_hdr hdr;
        u32 status;
        u32 max_sq;
        u32 max_rq;
        u32 max_cq;
        u32 max_eq;
        u32 max_db;
        u32 max_mst;
        u32 max_cq_mod_ctx;
        u32 max_mod_cq;
        u32 max_msix;
}; /* HW DATA */

/* GDMA_LIST_DEVICES */
struct gdma_list_devices_resp {
        struct gdma_resp_hdr hdr;
        u32 num_of_devs;
        u32 reserved;
        struct gdma_dev_id devs[64];
}; /* HW DATA */

/* GDMA_REGISTER_DEVICE */
struct gdma_register_device_resp {
        struct gdma_resp_hdr hdr;
        u32 pdid;
        u32 gpa_mkey;
        u32 db_id;
}; /* HW DATA */

/* GDMA_CREATE_QUEUE */
struct gdma_create_queue_req {
        struct gdma_req_hdr hdr;
        u32 type;
        u32 reserved1;
        u32 pdid;
        u32 doolbell_id;
        u64 gdma_region;
        u32 reserved2;
        u32 queue_size;
        u32 log2_throttle_limit;
        u32 eq_pci_msix_index;
        u32 cq_mod_ctx_id;
        u32 cq_parent_eq_id;
        u8  rq_drop_on_overrun;
        u8  rq_err_on_wqe_overflow;
        u8  rq_chain_rec_wqes;
        u8  sq_hw_db;
        u32 reserved3;
}; /* HW DATA */

struct gdma_create_queue_resp {
        struct gdma_resp_hdr hdr;
        u32 queue_index;
}; /* HW DATA */

/* GDMA_DISABLE_QUEUE */
struct gdma_disable_queue_req {
        struct gdma_req_hdr hdr;
        u32 type;
        u32 queue_index;
        u32 alloc_res_id_on_creation;
}; /* HW DATA */

/* GDMA_CREATE_DMA_REGION */
struct gdma_create_dma_region_req {
        struct gdma_req_hdr hdr;

        /* The total size of the DMA region */
        u64 length;

        /* The offset in the first page */
        u32 offset_in_page;

        /* enum gdma_page_type */
        u32 gdma_page_type;

        /* The total number of pages */
        u32 page_count;

        /* If page_addr_list_len is smaller than page_count,
         * the remaining page addresses will be added via the
         * message GDMA_DMA_REGION_ADD_PAGES.
         */
        u32 page_addr_list_len;
        u64 page_addr_list[];
}; /* HW DATA */

struct gdma_create_dma_region_resp {
        struct gdma_resp_hdr hdr;
        u64 gdma_region;
}; /* HW DATA */

/* GDMA_DMA_REGION_ADD_PAGES */
struct gdma_dma_region_add_pages_req {
        struct gdma_req_hdr hdr;

        u64 gdma_region;

        u32 page_addr_list_len;
        u32 reserved3;

        u64 page_addr_list[];
}; /* HW DATA */

/* GDMA_DESTROY_DMA_REGION */
struct gdma_destroy_dma_region_req {
        struct gdma_req_hdr hdr;

        u64 gdma_region;
}; /* HW DATA */

int mana_gd_verify_vf_version(struct pci_dev *pdev);

int mana_gd_register_device(struct gdma_dev *gd);
int mana_gd_deregister_device(struct gdma_dev *gd);

int mana_gd_post_work_request(struct gdma_queue *wq,
                              const struct gdma_wqe_request *wqe_req,
                              struct gdma_posted_wqe_info *wqe_info);

int mana_gd_post_and_ring(struct gdma_queue *queue,
                          const struct gdma_wqe_request *wqe,
                          struct gdma_posted_wqe_info *wqe_info);

int mana_gd_alloc_res_map(u32 res_avail, struct gdma_resource *r);
void mana_gd_free_res_map(struct gdma_resource *r);

void mana_gd_wq_ring_doorbell(struct gdma_context *gc,
                              struct gdma_queue *queue);

int mana_gd_alloc_memory(struct gdma_context *gc, unsigned int length,
                         struct gdma_mem_info *gmi);

void mana_gd_free_memory(struct gdma_mem_info *gmi);

int mana_gd_send_request(struct gdma_context *gc, u32 req_len, const void *req,
                         u32 resp_len, void *resp);
#endif /* _GDMA_H */