/*
 * 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: contigous 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__ */