/* SPDX-License-Identifier: GPL-2.0 */
/*
 * linux/drivers/char/hpilo.h
 *
 * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
 *      David Altobelli <david.altobelli@hp.com>
 */
#ifndef __HPILO_H
#define __HPILO_H

#define ILO_NAME "hpilo"

/* iLO ASIC PCI revision id */
#define PCI_REV_ID_NECHES       7

/* max number of open channel control blocks per device, hw limited to 32 */
#define MAX_CCB        24
/* min number of open channel control blocks per device, hw limited to 32 */
#define MIN_CCB         8
/* max number of supported devices */
#define MAX_ILO_DEV     1
/* max number of files */
#define MAX_OPEN        (MAX_CCB * MAX_ILO_DEV)
/* total wait time in usec */
#define MAX_WAIT_TIME   10000
/* per spin wait time in usec */
#define WAIT_TIME       10
/* spin counter for open/close delay */
#define MAX_WAIT        (MAX_WAIT_TIME / WAIT_TIME)

/*
 * Per device, used to track global memory allocations.
 */
struct ilo_hwinfo {
        /* mmio registers on device */
        char __iomem *mmio_vaddr;

        /* doorbell registers on device */
        char __iomem *db_vaddr;

        /* shared memory on device used for channel control blocks */
        char __iomem *ram_vaddr;

        /* files corresponding to this device */
        struct ccb_data *ccb_alloc[MAX_CCB];

        struct pci_dev *ilo_dev;

        /*
         * open_lock      serializes ccb_cnt during open and close
         * [ irq disabled ]
         * -> alloc_lock  used when adding/removing/searching ccb_alloc,
         *                which represents all ccbs open on the device
         * --> fifo_lock  controls access to fifo queues shared with hw
         *
         * Locks must be taken in this order, but open_lock and alloc_lock
         * are optional, they do not need to be held in order to take a
         * lower level lock.
         */
        spinlock_t open_lock;
        spinlock_t alloc_lock;
        spinlock_t fifo_lock;

        struct cdev cdev;
};

/* offset from mmio_vaddr for enabling doorbell interrupts */
#define DB_IRQ          0xB2
/* offset from mmio_vaddr for outbound communications */
#define DB_OUT          0xD4
/* DB_OUT reset bit */
#define DB_RESET        26

/*
 * Channel control block. Used to manage hardware queues.
 * The format must match hw's version.  The hw ccb is 128 bytes,
 * but the context area shouldn't be touched by the driver.
 */
#define ILOSW_CCB_SZ    64
#define ILOHW_CCB_SZ    128
struct ccb {
        union {
                char *send_fifobar;
                u64 send_fifobar_pa;
        } ccb_u1;
        union {
                char *send_desc;
                u64 send_desc_pa;
        } ccb_u2;
        u64 send_ctrl;

        union {
                char *recv_fifobar;
                u64 recv_fifobar_pa;
        } ccb_u3;
        union {
                char *recv_desc;
                u64 recv_desc_pa;
        } ccb_u4;
        u64 recv_ctrl;

        union {
                char __iomem *db_base;
                u64 padding5;
        } ccb_u5;

        u64 channel;

        /* unused context area (64 bytes) */
};

/* ccb queue parameters */
#define SENDQ           1
#define RECVQ           2
#define NR_QENTRY       4
#define L2_QENTRY_SZ    12

/* ccb ctrl bitfields */
#define CTRL_BITPOS_L2SZ             0
#define CTRL_BITPOS_FIFOINDEXMASK    4
#define CTRL_BITPOS_DESCLIMIT        18
#define CTRL_BITPOS_A                30
#define CTRL_BITPOS_G                31

/* ccb doorbell macros */
#define L2_DB_SIZE              14
#define ONE_DB_SIZE             (1 << L2_DB_SIZE)

/*
 * Per fd structure used to track the ccb allocated to that dev file.
 */
struct ccb_data {
        /* software version of ccb, using virtual addrs */
        struct ccb  driver_ccb;

        /* hardware version of ccb, using physical addrs */
        struct ccb  ilo_ccb;

        /* hardware ccb is written to this shared mapped device memory */
        struct ccb __iomem *mapped_ccb;

        /* dma'able memory used for send/recv queues */
        void       *dma_va;
        dma_addr_t  dma_pa;
        size_t      dma_size;

        /* pointer to hardware device info */
        struct ilo_hwinfo *ilo_hw;

        /* queue for this ccb to wait for recv data */
        wait_queue_head_t ccb_waitq;

        /* usage count, to allow for shared ccb's */
        int         ccb_cnt;

        /* open wanted exclusive access to this ccb */
        int         ccb_excl;
};

/*
 * FIFO queue structure, shared with hw.
 */
#define ILO_START_ALIGN 4096
#define ILO_CACHE_SZ     128
struct fifo {
        u64 nrents;     /* user requested number of fifo entries */
        u64 imask;  /* mask to extract valid fifo index */
        u64 merge;      /*  O/C bits to merge in during enqueue operation */
        u64 reset;      /* set to non-zero when the target device resets */
        u8  pad_0[ILO_CACHE_SZ - (sizeof(u64) * 4)];

        u64 head;
        u8  pad_1[ILO_CACHE_SZ - (sizeof(u64))];

        u64 tail;
        u8  pad_2[ILO_CACHE_SZ - (sizeof(u64))];

        u64 fifobar[];
};

/* convert between struct fifo, and the fifobar, which is saved in the ccb */
#define FIFOHANDLESIZE (sizeof(struct fifo))
#define FIFOBARTOHANDLE(_fifo) \
        ((struct fifo *)(((char *)(_fifo)) - FIFOHANDLESIZE))

/* the number of qwords to consume from the entry descriptor */
#define ENTRY_BITPOS_QWORDS      0
/* descriptor index number (within a specified queue) */
#define ENTRY_BITPOS_DESCRIPTOR  10
/* state bit, fifo entry consumed by consumer */
#define ENTRY_BITPOS_C           22
/* state bit, fifo entry is occupied */
#define ENTRY_BITPOS_O           23

#define ENTRY_BITS_QWORDS        10
#define ENTRY_BITS_DESCRIPTOR    12
#define ENTRY_BITS_C             1
#define ENTRY_BITS_O             1
#define ENTRY_BITS_TOTAL        \
        (ENTRY_BITS_C + ENTRY_BITS_O + \
         ENTRY_BITS_QWORDS + ENTRY_BITS_DESCRIPTOR)

/* extract various entry fields */
#define ENTRY_MASK ((1 << ENTRY_BITS_TOTAL) - 1)
#define ENTRY_MASK_C (((1 << ENTRY_BITS_C) - 1) << ENTRY_BITPOS_C)
#define ENTRY_MASK_O (((1 << ENTRY_BITS_O) - 1) << ENTRY_BITPOS_O)
#define ENTRY_MASK_QWORDS \
        (((1 << ENTRY_BITS_QWORDS) - 1) << ENTRY_BITPOS_QWORDS)
#define ENTRY_MASK_DESCRIPTOR \
        (((1 << ENTRY_BITS_DESCRIPTOR) - 1) << ENTRY_BITPOS_DESCRIPTOR)

#define ENTRY_MASK_NOSTATE (ENTRY_MASK >> (ENTRY_BITS_C + ENTRY_BITS_O))

#endif /* __HPILO_H */