/* SPDX-License-Identifier: GPL-2.0 */
/* Marvell Octeon EP (EndPoint) Ethernet Driver
 *
 * Copyright (C) 2020 Marvell.
 *
 */
 #ifndef __OCTEP_CTRL_MBOX_H__
#define __OCTEP_CTRL_MBOX_H__

/*              barmem structure
 * |===========================================|
 * |Info (16 + 120 + 120 = 256 bytes)          |
 * |-------------------------------------------|
 * |magic number (8 bytes)                     |
 * |bar memory size (4 bytes)                  |
 * |reserved (4 bytes)                         |
 * |-------------------------------------------|
 * |host version (8 bytes)                     |
 * |    low 32 bits                            |
 * |host status (8 bytes)                      |
 * |host reserved (104 bytes)                  |
 * |-------------------------------------------|
 * |fw version's (8 bytes)                     |
 * |    min=high 32 bits, max=low 32 bits      |
 * |fw status (8 bytes)                        |
 * |fw reserved (104 bytes)                    |
 * |===========================================|
 * |Host to Fw Queue info (16 bytes)           |
 * |-------------------------------------------|
 * |producer index (4 bytes)                   |
 * |consumer index (4 bytes)                   |
 * |max element size (4 bytes)                 |
 * |reserved (4 bytes)                         |
 * |===========================================|
 * |Fw to Host Queue info (16 bytes)           |
 * |-------------------------------------------|
 * |producer index (4 bytes)                   |
 * |consumer index (4 bytes)                   |
 * |max element size (4 bytes)                 |
 * |reserved (4 bytes)                         |
 * |===========================================|
 * |Host to Fw Queue ((total size-288/2) bytes)|
 * |-------------------------------------------|
 * |                                           |
 * |===========================================|
 * |===========================================|
 * |Fw to Host Queue ((total size-288/2) bytes)|
 * |-------------------------------------------|
 * |                                           |
 * |===========================================|
 */

#define OCTEP_CTRL_MBOX_MAGIC_NUMBER                    0xdeaddeadbeefbeefull

/* Valid request message */
#define OCTEP_CTRL_MBOX_MSG_HDR_FLAG_REQ                BIT(0)
/* Valid response message */
#define OCTEP_CTRL_MBOX_MSG_HDR_FLAG_RESP               BIT(1)
/* Valid notification, no response required */
#define OCTEP_CTRL_MBOX_MSG_HDR_FLAG_NOTIFY             BIT(2)
/* Valid custom message */
#define OCTEP_CTRL_MBOX_MSG_HDR_FLAG_CUSTOM             BIT(3)

#define OCTEP_CTRL_MBOX_MSG_DESC_MAX                    4

enum octep_ctrl_mbox_status {
        OCTEP_CTRL_MBOX_STATUS_INVALID = 0,
        OCTEP_CTRL_MBOX_STATUS_INIT,
        OCTEP_CTRL_MBOX_STATUS_READY,
        OCTEP_CTRL_MBOX_STATUS_UNINIT
};

/* mbox message */
union octep_ctrl_mbox_msg_hdr {
        u64 words[2];
        struct {
                /* must be 0 */
                u16 reserved1:15;
                /* vf_idx is valid if 1 */
                u16 is_vf:1;
                /* sender vf index 0-(n-1), 0 if (is_vf==0) */
                u16 vf_idx;
                /* total size of message excluding header */
                u32 sz;
                /* OCTEP_CTRL_MBOX_MSG_HDR_FLAG_* */
                u32 flags;
                /* identifier to match responses */
                u16 msg_id;
                u16 reserved2;
        } s;
};

/* mbox message buffer */
struct octep_ctrl_mbox_msg_buf {
        u32 reserved1;
        u16 reserved2;
        /* size of buffer */
        u16 sz;
        /* pointer to message buffer */
        void *msg;
};

/* mbox message */
struct octep_ctrl_mbox_msg {
        /* mbox transaction header */
        union octep_ctrl_mbox_msg_hdr hdr;
        /* number of sg buffer's */
        int sg_num;
        /* message buffer's */
        struct octep_ctrl_mbox_msg_buf sg_list[OCTEP_CTRL_MBOX_MSG_DESC_MAX];
};

/* Mbox queue */
struct octep_ctrl_mbox_q {
        /* size of queue buffer */
        u32 sz;
        /* producer address in bar mem */
        u8 __iomem *hw_prod;
        /* consumer address in bar mem */
        u8 __iomem *hw_cons;
        /* q base address in bar mem */
        u8 __iomem *hw_q;
};

struct octep_ctrl_mbox {
        /* control plane version */
        u64 version;
        /* size of bar memory */
        u32 barmem_sz;
        /* pointer to BAR memory */
        u8 __iomem *barmem;
        /* host-to-fw queue */
        struct octep_ctrl_mbox_q h2fq;
        /* fw-to-host queue */
        struct octep_ctrl_mbox_q f2hq;
        /* lock for h2fq */
        struct mutex h2fq_lock;
        /* lock for f2hq */
        struct mutex f2hq_lock;
        /* Min control plane version supported by firmware */
        u32 min_fw_version;
        /* Max control plane version supported by firmware */
        u32 max_fw_version;
};

/* Initialize control mbox.
 *
 * @param mbox: non-null pointer to struct octep_ctrl_mbox.
 *
 * return value: 0 on success, -errno on failure.
 */
int octep_ctrl_mbox_init(struct octep_ctrl_mbox *mbox);

/* Send mbox message.
 *
 * @param mbox: non-null pointer to struct octep_ctrl_mbox.
 * @param msg:  non-null pointer to struct octep_ctrl_mbox_msg.
 *              Caller should fill msg.sz and msg.desc.sz for each message.
 *
 * return value: 0 on success, -errno on failure.
 */
int octep_ctrl_mbox_send(struct octep_ctrl_mbox *mbox, struct octep_ctrl_mbox_msg *msg);

/* Retrieve mbox message.
 *
 * @param mbox: non-null pointer to struct octep_ctrl_mbox.
 * @param msg:  non-null pointer to struct octep_ctrl_mbox_msg.
 *              Caller should fill msg.sz and msg.desc.sz for each message.
 *
 * return value: 0 on success, -errno on failure.
 */
int octep_ctrl_mbox_recv(struct octep_ctrl_mbox *mbox, struct octep_ctrl_mbox_msg *msg);

/* Uninitialize control mbox.
 *
 * @param mbox: non-null pointer to struct octep_ctrl_mbox.
 *
 * return value: 0 on success, -errno on failure.
 */
int octep_ctrl_mbox_uninit(struct octep_ctrl_mbox *mbox);

#endif /* __OCTEP_CTRL_MBOX_H__ */