/*
 * This file is part of the Chelsio T4 PCI-E SR-IOV Virtual Function Ethernet
 * driver for Linux.
 *
 * Copyright (c) 2009-2010 Chelsio Communications, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * 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 AUTHORS OR COPYRIGHT HOLDERS
 * 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.
 */

/*
 * This file should not be included directly.  Include t4vf_common.h instead.
 */

#ifndef __CXGB4VF_ADAPTER_H__
#define __CXGB4VF_ADAPTER_H__

#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/if_ether.h>
#include <linux/netdevice.h>

#include "../cxgb4/t4_hw.h"

/*
 * Constants of the implementation.
 */
enum {
        MAX_NPORTS      = 1,            /* max # of "ports" */
        MAX_PORT_QSETS  = 8,            /* max # of Queue Sets / "port" */
        MAX_ETH_QSETS   = MAX_NPORTS*MAX_PORT_QSETS,

        /*
         * MSI-X interrupt index usage.
         */
        MSIX_FW         = 0,            /* MSI-X index for firmware Q */
        MSIX_IQFLINT    = 1,            /* MSI-X index base for Ingress Qs */
        MSIX_EXTRAS     = 1,
        MSIX_ENTRIES    = MAX_ETH_QSETS + MSIX_EXTRAS,

        /*
         * The maximum number of Ingress and Egress Queues is determined by
         * the maximum number of "Queue Sets" which we support plus any
         * ancillary queues.  Each "Queue Set" requires one Ingress Queue
         * for RX Packet Ingress Event notifications and two Egress Queues for
         * a Free List and an Ethernet TX list.
         */
        INGQ_EXTRAS     = 2,            /* firmware event queue and */
                                        /*   forwarded interrupts */
        MAX_INGQ        = MAX_ETH_QSETS+INGQ_EXTRAS,
        MAX_EGRQ        = MAX_ETH_QSETS*2,
};

/*
 * Forward structure definition references.
 */
struct adapter;
struct sge_eth_rxq;
struct sge_rspq;

/*
 * Per-"port" information.  This is really per-Virtual Interface information
 * but the use of the "port" nomanclature makes it easier to go back and forth
 * between the PF and VF drivers ...
 */
struct port_info {
        struct adapter *adapter;        /* our adapter */
        u16 viid;                       /* virtual interface ID */
        s16 xact_addr_filt;             /* index of our MAC address filter */
        u16 rss_size;                   /* size of VI's RSS table slice */
        u8 pidx;                        /* index into adapter port[] */
        u8 port_id;                     /* physical port ID */
        u8 nqsets;                      /* # of "Queue Sets" */
        u8 first_qset;                  /* index of first "Queue Set" */
        struct link_config link_cfg;    /* physical port configuration */
};

/*
 * Scatter Gather Engine resources for the "adapter".  Our ingress and egress
 * queues are organized into "Queue Sets" with one ingress and one egress
 * queue per Queue Set.  These Queue Sets are aportionable between the "ports"
 * (Virtual Interfaces).  One extra ingress queue is used to receive
 * asynchronous messages from the firmware.  Note that the "Queue IDs" that we
 * use here are really "Relative Queue IDs" which are returned as part of the
 * firmware command to allocate queues.  These queue IDs are relative to the
 * absolute Queue ID base of the section of the Queue ID space allocated to
 * the PF/VF.
 */

/*
 * SGE free-list queue state.
 */
struct rx_sw_desc;
struct sge_fl {
        unsigned int avail;             /* # of available RX buffers */
        unsigned int pend_cred;         /* new buffers since last FL DB ring */
        unsigned int cidx;              /* consumer index */
        unsigned int pidx;              /* producer index */
        unsigned long alloc_failed;     /* # of buffer allocation failures */
        unsigned long large_alloc_failed;
        unsigned long starving;         /* # of times FL was found starving */

        /*
         * Write-once/infrequently fields.
         * -------------------------------
         */

        unsigned int cntxt_id;          /* SGE relative QID for the free list */
        unsigned int abs_id;            /* SGE absolute QID for the free list */
        unsigned int size;              /* capacity of free list */
        struct rx_sw_desc *sdesc;       /* address of SW RX descriptor ring */
        __be64 *desc;                   /* address of HW RX descriptor ring */
        dma_addr_t addr;                /* PCI bus address of hardware ring */
};

/*
 * An ingress packet gather list.
 */
struct pkt_gl {
        struct page_frag frags[MAX_SKB_FRAGS];
        void *va;                       /* virtual address of first byte */
        unsigned int nfrags;            /* # of fragments */
        unsigned int tot_len;           /* total length of fragments */
};

typedef int (*rspq_handler_t)(struct sge_rspq *, const __be64 *,
                              const struct pkt_gl *);

/*
 * State for an SGE Response Queue.
 */
struct sge_rspq {
        struct napi_struct napi;        /* NAPI scheduling control */
        const __be64 *cur_desc;         /* current descriptor in queue */
        unsigned int cidx;              /* consumer index */
        u8 gen;                         /* current generation bit */
        u8 next_intr_params;            /* holdoff params for next interrupt */
        int offset;                     /* offset into current FL buffer */

        unsigned int unhandled_irqs;    /* bogus interrupts */

        /*
         * Write-once/infrequently fields.
         * -------------------------------
         */

        u8 intr_params;                 /* interrupt holdoff parameters */
        u8 pktcnt_idx;                  /* interrupt packet threshold */
        u8 idx;                         /* queue index within its group */
        u16 cntxt_id;                   /* SGE rel QID for the response Q */
        u16 abs_id;                     /* SGE abs QID for the response Q */
        __be64 *desc;                   /* address of hardware response ring */
        dma_addr_t phys_addr;           /* PCI bus address of ring */
        unsigned int iqe_len;           /* entry size */
        unsigned int size;              /* capcity of response Q */
        struct adapter *adapter;        /* our adapter */
        struct net_device *netdev;      /* associated net device */
        rspq_handler_t handler;         /* the handler for this response Q */
};

/*
 * Ethernet queue statistics
 */
struct sge_eth_stats {
        unsigned long pkts;             /* # of ethernet packets */
        unsigned long lro_pkts;         /* # of LRO super packets */
        unsigned long lro_merged;       /* # of wire packets merged by LRO */
        unsigned long rx_cso;           /* # of Rx checksum offloads */
        unsigned long vlan_ex;          /* # of Rx VLAN extractions */
        unsigned long rx_drops;         /* # of packets dropped due to no mem */
};

/*
 * State for an Ethernet Receive Queue.
 */
struct sge_eth_rxq {
        struct sge_rspq rspq;           /* Response Queue */
        struct sge_fl fl;               /* Free List */
        struct sge_eth_stats stats;     /* receive statistics */
};

/*
 * SGE Transmit Queue state.  This contains all of the resources associated
 * with the hardware status of a TX Queue which is a circular ring of hardware
 * TX Descriptors.  For convenience, it also contains a pointer to a parallel
 * "Software Descriptor" array but we don't know anything about it here other
 * than its type name.
 */
struct tx_desc {
        /*
         * Egress Queues are measured in units of SGE_EQ_IDXSIZE by the
         * hardware: Sizes, Producer and Consumer indices, etc.
         */
        __be64 flit[SGE_EQ_IDXSIZE/sizeof(__be64)];
};
struct tx_sw_desc;
struct sge_txq {
        unsigned int in_use;            /* # of in-use TX descriptors */
        unsigned int size;              /* # of descriptors */
        unsigned int cidx;              /* SW consumer index */
        unsigned int pidx;              /* producer index */
        unsigned long stops;            /* # of times queue has been stopped */
        unsigned long restarts;         /* # of queue restarts */

        /*
         * Write-once/infrequently fields.
         * -------------------------------
         */

        unsigned int cntxt_id;          /* SGE relative QID for the TX Q */
        unsigned int abs_id;            /* SGE absolute QID for the TX Q */
        struct tx_desc *desc;           /* address of HW TX descriptor ring */
        struct tx_sw_desc *sdesc;       /* address of SW TX descriptor ring */
        struct sge_qstat *stat;         /* queue status entry */
        dma_addr_t phys_addr;           /* PCI bus address of hardware ring */
};

/*
 * State for an Ethernet Transmit Queue.
 */
struct sge_eth_txq {
        struct sge_txq q;               /* SGE TX Queue */
        struct netdev_queue *txq;       /* associated netdev TX queue */
        unsigned long tso;              /* # of TSO requests */
        unsigned long tx_cso;           /* # of TX checksum offloads */
        unsigned long vlan_ins;         /* # of TX VLAN insertions */
        unsigned long mapping_err;      /* # of I/O MMU packet mapping errors */
};

/*
 * The complete set of Scatter/Gather Engine resources.
 */
struct sge {
        /*
         * Our "Queue Sets" ...
         */
        struct sge_eth_txq ethtxq[MAX_ETH_QSETS];
        struct sge_eth_rxq ethrxq[MAX_ETH_QSETS];

        /*
         * Extra ingress queues for asynchronous firmware events and
         * forwarded interrupts (when in MSI mode).
         */
        struct sge_rspq fw_evtq ____cacheline_aligned_in_smp;

        struct sge_rspq intrq ____cacheline_aligned_in_smp;
        spinlock_t intrq_lock;

        /*
         * State for managing "starving Free Lists" -- Free Lists which have
         * fallen below a certain threshold of buffers available to the
         * hardware and attempts to refill them up to that threshold have
         * failed.  We have a regular "slow tick" timer process which will
         * make periodic attempts to refill these starving Free Lists ...
         */
        DECLARE_BITMAP(starving_fl, MAX_EGRQ);
        struct timer_list rx_timer;

        /*
         * State for cleaning up completed TX descriptors.
         */
        struct timer_list tx_timer;

        /*
         * Write-once/infrequently fields.
         * -------------------------------
         */

        u16 max_ethqsets;               /* # of available Ethernet queue sets */
        u16 ethqsets;                   /* # of active Ethernet queue sets */
        u16 ethtxq_rover;               /* Tx queue to clean up next */
        u16 timer_val[SGE_NTIMERS];     /* interrupt holdoff timer array */
        u8 counter_val[SGE_NCOUNTERS];  /* interrupt RX threshold array */

        /*
         * Reverse maps from Absolute Queue IDs to associated queue pointers.
         * The absolute Queue IDs are in a compact range which start at a
         * [potentially large] Base Queue ID.  We perform the reverse map by
         * first converting the Absolute Queue ID into a Relative Queue ID by
         * subtracting off the Base Queue ID and then use a Relative Queue ID
         * indexed table to get the pointer to the corresponding software
         * queue structure.
         */
        unsigned int egr_base;
        unsigned int ingr_base;
        void *egr_map[MAX_EGRQ];
        struct sge_rspq *ingr_map[MAX_INGQ];
};

/*
 * Utility macros to convert Absolute- to Relative-Queue indices and Egress-
 * and Ingress-Queues.  The EQ_MAP() and IQ_MAP() macros which provide
 * pointers to Ingress- and Egress-Queues can be used as both L- and R-values
 */
#define EQ_IDX(s, abs_id) ((unsigned int)((abs_id) - (s)->egr_base))
#define IQ_IDX(s, abs_id) ((unsigned int)((abs_id) - (s)->ingr_base))

#define EQ_MAP(s, abs_id) ((s)->egr_map[EQ_IDX(s, abs_id)])
#define IQ_MAP(s, abs_id) ((s)->ingr_map[IQ_IDX(s, abs_id)])

/*
 * Macro to iterate across Queue Sets ("rxq" is a historic misnomer).
 */
#define for_each_ethrxq(sge, iter) \
        for (iter = 0; iter < (sge)->ethqsets; iter++)

/*
 * Per-"adapter" (Virtual Function) information.
 */
struct adapter {
        /* PCI resources */
        void __iomem *regs;
        struct pci_dev *pdev;
        struct device *pdev_dev;

        /* "adapter" resources */
        unsigned long registered_device_map;
        unsigned long open_device_map;
        unsigned long flags;
        enum chip_type chip;
        struct adapter_params params;

        /* queue and interrupt resources */
        struct {
                unsigned short vec;
                char desc[22];
        } msix_info[MSIX_ENTRIES];
        struct sge sge;

        /* Linux network device resources */
        struct net_device *port[MAX_NPORTS];
        const char *name;
        unsigned int msg_enable;

        /* debugfs resources */
        struct dentry *debugfs_root;

        /* various locks */
        spinlock_t stats_lock;
};

enum { /* adapter flags */
        FULL_INIT_DONE     = (1UL << 0),
        USING_MSI          = (1UL << 1),
        USING_MSIX         = (1UL << 2),
        QUEUES_BOUND       = (1UL << 3),
};

/*
 * The following register read/write routine definitions are required by
 * the common code.
 */

/**
 * t4_read_reg - read a HW register
 * @adapter: the adapter
 * @reg_addr: the register address
 *
 * Returns the 32-bit value of the given HW register.
 */
static inline u32 t4_read_reg(struct adapter *adapter, u32 reg_addr)
{
        return readl(adapter->regs + reg_addr);
}

/**
 * t4_write_reg - write a HW register
 * @adapter: the adapter
 * @reg_addr: the register address
 * @val: the value to write
 *
 * Write a 32-bit value into the given HW register.
 */
static inline void t4_write_reg(struct adapter *adapter, u32 reg_addr, u32 val)
{
        writel(val, adapter->regs + reg_addr);
}

#ifndef readq
static inline u64 readq(const volatile void __iomem *addr)
{
        return readl(addr) + ((u64)readl(addr + 4) << 32);
}

static inline void writeq(u64 val, volatile void __iomem *addr)
{
        writel(val, addr);
        writel(val >> 32, addr + 4);
}
#endif

/**
 * t4_read_reg64 - read a 64-bit HW register
 * @adapter: the adapter
 * @reg_addr: the register address
 *
 * Returns the 64-bit value of the given HW register.
 */
static inline u64 t4_read_reg64(struct adapter *adapter, u32 reg_addr)
{
        return readq(adapter->regs + reg_addr);
}

/**
 * t4_write_reg64 - write a 64-bit HW register
 * @adapter: the adapter
 * @reg_addr: the register address
 * @val: the value to write
 *
 * Write a 64-bit value into the given HW register.
 */
static inline void t4_write_reg64(struct adapter *adapter, u32 reg_addr,
                                  u64 val)
{
        writeq(val, adapter->regs + reg_addr);
}

/**
 * port_name - return the string name of a port
 * @adapter: the adapter
 * @pidx: the port index
 *
 * Return the string name of the selected port.
 */
static inline const char *port_name(struct adapter *adapter, int pidx)
{
        return adapter->port[pidx]->name;
}

/**
 * t4_os_set_hw_addr - store a port's MAC address in SW
 * @adapter: the adapter
 * @pidx: the port index
 * @hw_addr: the Ethernet address
 *
 * Store the Ethernet address of the given port in SW.  Called by the common
 * code when it retrieves a port's Ethernet address from EEPROM.
 */
static inline void t4_os_set_hw_addr(struct adapter *adapter, int pidx,
                                     u8 hw_addr[])
{
        memcpy(adapter->port[pidx]->dev_addr, hw_addr, ETH_ALEN);
}

/**
 * netdev2pinfo - return the port_info structure associated with a net_device
 * @dev: the netdev
 *
 * Return the struct port_info associated with a net_device
 */
static inline struct port_info *netdev2pinfo(const struct net_device *dev)
{
        return netdev_priv(dev);
}

/**
 * adap2pinfo - return the port_info of a port
 * @adap: the adapter
 * @pidx: the port index
 *
 * Return the port_info structure for the adapter.
 */
static inline struct port_info *adap2pinfo(struct adapter *adapter, int pidx)
{
        return netdev_priv(adapter->port[pidx]);
}

/**
 * netdev2adap - return the adapter structure associated with a net_device
 * @dev: the netdev
 *
 * Return the struct adapter associated with a net_device
 */
static inline struct adapter *netdev2adap(const struct net_device *dev)
{
        return netdev2pinfo(dev)->adapter;
}

/*
 * OS "Callback" function declarations.  These are functions that the OS code
 * is "contracted" to provide for the common code.
 */
void t4vf_os_link_changed(struct adapter *, int, int);

/*
 * SGE function prototype declarations.
 */
int t4vf_sge_alloc_rxq(struct adapter *, struct sge_rspq *, bool,
                       struct net_device *, int,
                       struct sge_fl *, rspq_handler_t);
int t4vf_sge_alloc_eth_txq(struct adapter *, struct sge_eth_txq *,
                           struct net_device *, struct netdev_queue *,
                           unsigned int);
void t4vf_free_sge_resources(struct adapter *);

int t4vf_eth_xmit(struct sk_buff *, struct net_device *);
int t4vf_ethrx_handler(struct sge_rspq *, const __be64 *,
                       const struct pkt_gl *);

irq_handler_t t4vf_intr_handler(struct adapter *);
irqreturn_t t4vf_sge_intr_msix(int, void *);

int t4vf_sge_init(struct adapter *);
void t4vf_sge_start(struct adapter *);
void t4vf_sge_stop(struct adapter *);

#endif /* __CXGB4VF_ADAPTER_H__ */