/*
 * bdc.h - header for the BRCM BDC USB3.0 device controller
 *
 * Copyright (C) 2014 Broadcom Corporation
 *
 * Author: Ashwini Pahuja
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 */

#ifndef __LINUX_BDC_H__
#define __LINUX_BDC_H__

#include <linux/kernel.h>
#include <linux/usb.h>
#include <linux/device.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/dma-mapping.h>
#include <linux/mm.h>
#include <linux/debugfs.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <asm/unaligned.h>

#define BRCM_BDC_NAME "bdc_usb3"
#define BRCM_BDC_DESC "BDC device controller driver"

#define DMA_ADDR_INVALID        (~(dma_addr_t)0)

/* BDC command operation timeout in usec*/
#define BDC_CMD_TIMEOUT 1000
/* BDC controller operation timeout in usec*/
#define BDC_COP_TIMEOUT 500

/*
 * Maximum size of ep0 response buffer for ch9 requests,
 * the set_sel request uses 6 so far, the max.
*/
#define EP0_RESPONSE_BUFF  6
/* Start with SS as default */
#define EP0_MAX_PKT_SIZE 512

/* 64 entries in a SRR */
#define NUM_SR_ENTRIES  64

/* Num of bds per table */
#define NUM_BDS_PER_TABLE       32

/* Num of tables in bd list for control,bulk and Int ep */
#define NUM_TABLES      2

/* Num of tables in bd list for Isoch ep */
#define NUM_TABLES_ISOCH        6

/* U1 Timeout default: 248usec */
#define U1_TIMEOUT      0xf8

/* Interrupt coalescence in usec */
#define INT_CLS 500

/* Register offsets */
/* Configuration and Capability registers */
#define BDC_BDCCFG0     0x00
#define BDC_BDCCFG1     0x04
#define BDC_BDCCAP0     0x08
#define BDC_BDCCAP1     0x0c
#define BDC_CMDPAR0     0x10
#define BDC_CMDPAR1     0x14
#define BDC_CMDPAR2     0x18
#define BDC_CMDSC       0x1c
#define BDC_USPC        0x20
#define BDC_USPPMS      0x28
#define BDC_USPPM2      0x2c
#define BDC_SPBBAL      0x38
#define BDC_SPBBAH      0x3c
#define BDC_BDCSC       0x40
#define BDC_XSFNTF      0x4c

#define BDC_DVCSA       0x50
#define BDC_DVCSB       0x54
#define BDC_EPSTS0(n)   (0x60 + (n * 0x10))
#define BDC_EPSTS1(n)   (0x64 + (n * 0x10))
#define BDC_EPSTS2(n)   (0x68 + (n * 0x10))
#define BDC_EPSTS3(n)   (0x6c + (n * 0x10))
#define BDC_EPSTS4(n)   (0x70 + (n * 0x10))
#define BDC_EPSTS5(n)   (0x74 + (n * 0x10))
#define BDC_EPSTS6(n)   (0x78 + (n * 0x10))
#define BDC_EPSTS7(n)   (0x7c + (n * 0x10))
#define BDC_SRRBAL(n)   (0x200 + (n * 0x10))
#define BDC_SRRBAH(n)   (0x204 + (n * 0x10))
#define BDC_SRRINT(n)   (0x208 + (n * 0x10))
#define BDC_INTCTLS(n)  (0x20c + (n * 0x10))

/* Extended capability regs */
#define BDC_FSCNOC      0xcd4
#define BDC_FSCNIC      0xce4
#define NUM_NCS(p)      (p >> 28)

/* Register bit fields and Masks */
/* BDC Configuration 0 */
#define BDC_PGS(p)      (((p) & (0x7 << 8)) >> 8)
#define BDC_SPB(p)      (p & 0x7)

/* BDC Capability1 */
#define BDC_P64         (1 << 0)

/* BDC Command register */
#define BDC_CMD_FH      0xe
#define BDC_CMD_DNC     0x6
#define BDC_CMD_EPO     0x4
#define BDC_CMD_BLA     0x3
#define BDC_CMD_EPC     0x2
#define BDC_CMD_DVC     0x1
#define BDC_CMD_CWS             (0x1 << 5)
#define BDC_CMD_CST(p)          (((p) & (0xf << 6))>>6)
#define BDC_CMD_EPN(p)          ((p & 0x1f) << 10)
#define BDC_SUB_CMD_ADD         (0x1 << 17)
#define BDC_SUB_CMD_FWK         (0x4 << 17)
/* Reset sequence number */
#define BDC_CMD_EPO_RST_SN      (0x1 << 16)
#define BDC_CMD_EP0_XSD         (0x1 << 16)
#define BDC_SUB_CMD_ADD_EP      (0x1 << 17)
#define BDC_SUB_CMD_DRP_EP      (0x2 << 17)
#define BDC_SUB_CMD_EP_STP      (0x2 << 17)
#define BDC_SUB_CMD_EP_STL      (0x4 << 17)
#define BDC_SUB_CMD_EP_RST      (0x1 << 17)
#define BDC_CMD_SRD             (1 << 27)

/* CMD completion status */
#define BDC_CMDS_SUCC   0x1
#define BDC_CMDS_PARA   0x3
#define BDC_CMDS_STAT   0x4
#define BDC_CMDS_FAIL   0x5
#define BDC_CMDS_INTL   0x6
#define BDC_CMDS_BUSY   0xf

/* CMDSC Param 2 shifts */
#define EPT_SHIFT       22
#define MP_SHIFT        10
#define MB_SHIFT        6
#define EPM_SHIFT       4

/* BDC USPSC */
#define BDC_VBC         (1 << 31)
#define BDC_PRC         (1 << 30)
#define BDC_PCE         (1 << 29)
#define BDC_CFC         (1 << 28)
#define BDC_PCC         (1 << 27)
#define BDC_PSC         (1 << 26)
#define BDC_VBS         (1 << 25)
#define BDC_PRS         (1 << 24)
#define BDC_PCS         (1 << 23)
#define BDC_PSP(p)      (((p) & (0x7 << 20))>>20)
#define BDC_SCN         (1 << 8)
#define BDC_SDC         (1 << 7)
#define BDC_SWS         (1 << 4)

#define BDC_USPSC_RW    (BDC_SCN|BDC_SDC|BDC_SWS|0xf)
#define BDC_PSP(p)      (((p) & (0x7 << 20))>>20)

#define BDC_SPEED_FS    0x1
#define BDC_SPEED_LS    0x2
#define BDC_SPEED_HS    0x3
#define BDC_SPEED_SS    0x4

#define BDC_PST(p)      (p & 0xf)
#define BDC_PST_MASK    0xf

/* USPPMS */
#define BDC_U2E         (0x1 << 31)
#define BDC_U1E         (0x1 << 30)
#define BDC_U2A         (0x1 << 29)
#define BDC_PORT_W1S    (0x1 << 17)
#define BDC_U1T(p)      ((p) & 0xff)
#define BDC_U2T(p)      (((p) & 0xff) << 8)
#define BDC_U1T_MASK    0xff

/* USBPM2 */
/* Hardware LPM Enable */
#define BDC_HLE         (1 << 16)

/* BDC Status and Control */
#define BDC_COP_RST     (1 << 29)
#define BDC_COP_RUN     (2 << 29)
#define BDC_COP_STP     (4 << 29)

#define BDC_COP_MASK (BDC_COP_RST|BDC_COP_RUN|BDC_COP_STP)

#define BDC_COS         (1 << 28)
#define BDC_CSTS(p)     (((p) & (0x7 << 20)) >> 20)
#define BDC_MASK_MCW    (1 << 7)
#define BDC_GIE         (1 << 1)
#define BDC_GIP         (1 << 0)

#define BDC_HLT 1
#define BDC_NOR 2
#define BDC_OIP 7

/* Buffer descriptor and Status report bit fields and masks */
#define BD_TYPE_BITMASK (0xf)
#define BD_CHAIN        0xf

#define BD_TFS_SHIFT    4
#define BD_SOT          (1 << 26)
#define BD_EOT          (1 << 27)
#define BD_ISP          (1 << 29)
#define BD_IOC          (1 << 30)
#define BD_SBF          (1 << 31)

#define BD_INTR_TARGET(p)       (((p) & 0x1f) << 27)

#define BDC_SRR_RWS             (1 << 4)
#define BDC_SRR_RST             (1 << 3)
#define BDC_SRR_ISR             (1 << 2)
#define BDC_SRR_IE              (1 << 1)
#define BDC_SRR_IP              (1 << 0)
#define BDC_SRR_EPI(p)  (((p) & (0xff << 24)) >> 24)
#define BDC_SRR_DPI(p) (((p) & (0xff << 16)) >> 16)
#define BDC_SRR_DPI_MASK        0x00ff0000

#define MARK_CHAIN_BD   (BD_CHAIN|BD_EOT|BD_SOT)

/* Control transfer BD specific fields */
#define BD_DIR_IN               (1 << 25)

#define BDC_PTC_MASK    0xf0000000

/* status report defines */
#define SR_XSF          0
#define SR_USPC         4
#define SR_BD_LEN(p)    (p & 0xffffff)

#define XSF_SUCC        0x1
#define XSF_SHORT       0x3
#define XSF_BABB        0x4
#define XSF_SETUP_RECV  0x6
#define XSF_DATA_START  0x7
#define XSF_STATUS_START 0x8

#define XSF_STS(p) (((p) >> 28) & 0xf)

/* Transfer BD fields */
#define BD_LEN(p) ((p) & 0x1ffff)
#define BD_LTF          (1 << 25)
#define BD_TYPE_DS      0x1
#define BD_TYPE_SS      0x2

#define BDC_EP_ENABLED     (1 << 0)
#define BDC_EP_STALL       (1 << 1)
#define BDC_EP_STOP        (1 << 2)

/* One BD can transfer max 65536 bytes */
#define BD_MAX_BUFF_SIZE        (1 << 16)
/* Maximum bytes in one XFR, Refer to BDC spec */
#define MAX_XFR_LEN             16777215

/* defines for Force Header command */
#define DEV_NOTF_TYPE 6
#define FWK_SUBTYPE  1
#define TRA_PACKET   4

#define to_bdc_ep(e)            container_of(e, struct bdc_ep, usb_ep)
#define to_bdc_req(r)           container_of(r, struct bdc_req, usb_req)
#define gadget_to_bdc(g)        container_of(g, struct bdc, gadget)

/* FUNCTION WAKE DEV NOTIFICATION interval, USB3 spec table 8.13 */
#define BDC_TNOTIFY 2500 /*in ms*/
/* Devstatus bitfields */
#define REMOTE_WAKEUP_ISSUED    (1 << 16)
#define DEVICE_SUSPENDED        (1 << 17)
#define FUNC_WAKE_ISSUED        (1 << 18)
#define REMOTE_WAKE_ENABLE      (1 << USB_DEVICE_REMOTE_WAKEUP)

/* On disconnect, preserve these bits and clear rest */
#define DEVSTATUS_CLEAR         (1 << USB_DEVICE_SELF_POWERED)
/* Hardware and software Data structures */

/* Endpoint bd: buffer descriptor */
struct bdc_bd {
        __le32 offset[4];
};

/* Status report in Status report ring(srr) */
struct bdc_sr {
        __le32 offset[4];
};

/* bd_table: contiguous bd's in a table */
struct bd_table {
        struct bdc_bd *start_bd;
        /* dma address of start bd of table*/
        dma_addr_t dma;
};

/*
 * Each endpoint has a bdl(buffer descriptor list), bdl consists of 1 or more bd
 * table's chained to each other through a chain bd, every table has equal
 * number of bds. the software uses bdi(bd index) to refer to particular bd in
 * the list.
 */
struct bd_list {
        /* Array of bd table pointers*/
        struct bd_table **bd_table_array;
        /* How many tables chained to each other */
        int num_tabs;
        /* Max_bdi = num_tabs * num_bds_table - 1 */
        int max_bdi;
        /* current enq bdi from sw point of view */
        int eqp_bdi;
        /* current deq bdi from sw point of view */
        int hwd_bdi;
        /* numbers of bds per table */
        int num_bds_table;
};

struct bdc_req;

/* Representation of a transfer, one transfer can have multiple bd's */
struct bd_transfer {
        struct bdc_req *req;
        /* start bd index */
        int start_bdi;
        /* this will be the next hw dqp when this transfer completes */
        int next_hwd_bdi;
        /* number of bds in this transfer */
        int num_bds;
};

/*
 * Representation of a gadget request, every gadget request is contained
 * by 1 bd_transfer.
 */
struct bdc_req {
        struct usb_request      usb_req;
        struct list_head        queue;
        struct bdc_ep           *ep;
        /* only one Transfer per request */
        struct bd_transfer bd_xfr;
        int     epnum;
};

/* scratchpad buffer needed by bdc hardware */
struct bdc_scratchpad {
        dma_addr_t sp_dma;
        void *buff;
        u32 size;
};

/* endpoint representation */
struct bdc_ep {
        struct usb_ep   usb_ep;
        struct list_head queue;
        struct bdc *bdc;
        u8  ep_type;
        u8  dir;
        u8  ep_num;
        const struct usb_ss_ep_comp_descriptor  *comp_desc;
        const struct usb_endpoint_descriptor    *desc;
        unsigned int flags;
        char name[20];
        /* endpoint bd list*/
        struct bd_list bd_list;
        /*
         * HW generates extra event for multi bd tranfers, this flag helps in
         * ignoring the extra event
         */
        bool ignore_next_sr;
};

/* bdc cmmand parameter structure */
struct bdc_cmd_params {
        u32     param2;
        u32     param1;
        u32     param0;
};

/* status report ring(srr), currently one srr is supported for entire system */
struct srr {
        struct bdc_sr *sr_bds;
        u16     eqp_index;
        u16     dqp_index;
        dma_addr_t      dma_addr;
};

/* EP0 states */
enum bdc_ep0_state {
        WAIT_FOR_SETUP = 0,
        WAIT_FOR_DATA_START,
        WAIT_FOR_DATA_XMIT,
        WAIT_FOR_STATUS_START,
        WAIT_FOR_STATUS_XMIT,
        STATUS_PENDING
};

/* Link states */
enum bdc_link_state {
        BDC_LINK_STATE_U0       = 0x00,
        BDC_LINK_STATE_U3       = 0x03,
        BDC_LINK_STATE_RX_DET   = 0x05,
        BDC_LINK_STATE_RESUME   = 0x0f
};

/* representation of bdc */
struct bdc {
        struct usb_gadget       gadget;
        struct usb_gadget_driver        *gadget_driver;
        struct device   *dev;
        /* device lock */
        spinlock_t      lock;

        /* num of endpoints for a particular instantiation of IP */
        unsigned int num_eps;
        /*
         * Array of ep's, it uses the same index covention as bdc hw i.e.
         * 1 for ep0, 2 for 1out,3 for 1in ....
         */
        struct bdc_ep           **bdc_ep_array;
        void __iomem            *regs;
        struct bdc_scratchpad   scratchpad;
        u32     sp_buff_size;
        /* current driver supports 1 status ring */
        struct srr      srr;
        /* Last received setup packet */
        struct  usb_ctrlrequest setup_pkt;
        struct  bdc_req ep0_req;
        struct  bdc_req status_req;
        enum    bdc_ep0_state ep0_state;
        bool    delayed_status;
        bool    zlp_needed;
        bool    reinit;
        bool    pullup;
        /* Bits 0-15 are standard and 16-31 for proprietary information */
        u32     devstatus;
        int     irq;
        void    *mem;
        u32     dev_addr;
        /* DMA pools */
        struct dma_pool *bd_table_pool;
        u8              test_mode;
        /* array of callbacks for various status report handlers */
        void (*sr_handler[2])(struct bdc *, struct bdc_sr *);
        /* ep0 callback handlers */
        void (*sr_xsf_ep0[3])(struct bdc *, struct bdc_sr *);
        /* ep0 response buffer for ch9 requests like GET_STATUS and SET_SEL */
        unsigned char           ep0_response_buff[EP0_RESPONSE_BUFF];
        /*
         * Timer to check if host resumed transfer after bdc sent Func wake
         * notification  packet after a remote wakeup. if not, then resend the
         * Func Wake packet every 2.5 secs. Refer to USB3 spec section 8.5.6.4
         */
        struct delayed_work     func_wake_notify;
};

static inline u32 bdc_readl(void __iomem *base, u32 offset)
{
        return readl(base + offset);
}

static inline void bdc_writel(void __iomem *base, u32 offset, u32 value)
{
        writel(value, base + offset);
}

/* Buffer descriptor list operations */
void bdc_notify_xfr(struct bdc *, u32);
void bdc_softconn(struct bdc *);
void bdc_softdisconn(struct bdc *);
int bdc_run(struct bdc *);
int bdc_stop(struct bdc *);
int bdc_reset(struct bdc *);
int bdc_udc_init(struct bdc *);
void bdc_udc_exit(struct bdc *);
int bdc_reinit(struct bdc *);

/* Status report handlers */
/* Upstream port status change sr */
void bdc_sr_uspc(struct bdc *, struct bdc_sr *);
/* transfer sr */
void bdc_sr_xsf(struct bdc *, struct bdc_sr *);
/* EP0 XSF handlers */
void bdc_xsf_ep0_setup_recv(struct bdc *, struct bdc_sr *);
void bdc_xsf_ep0_data_start(struct bdc *, struct bdc_sr *);
void bdc_xsf_ep0_status_start(struct bdc *, struct bdc_sr *);

#endif /* __LINUX_BDC_H__ */