drivers/usb/hcd/ehci.h

/*
 * Copyright (c) 2001 by David Brownell
 * 
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef __LINUX_EHCI_HCD_H
#define __LINUX_EHCI_HCD_H

/* definitions used for the EHCI driver */

/* ehci_hcd->lock guards shared data against other CPUs:
 *   ehci_hcd:	async, reclaim, periodic (and shadow), ...
 *   hcd_dev:	ep[]
 *   ehci_qh:	qh_next, qtd_list
 *   ehci_qtd:	qtd_list
 *
 * Also, hold this lock when talking to HC registers or
 * when updating hw_* fields in shared qh/qtd/... structures.
 */

#define	EHCI_MAX_ROOT_PORTS	15		/* see HCS_N_PORTS */

struct ehci_hcd {			/* one per controller */
	spinlock_t		lock;

	/* async schedule support */
	struct ehci_qh		*async;
	struct ehci_qh		*reclaim;
	int			reclaim_ready;

	/* periodic schedule support */
#define	DEFAULT_I_TDPS		1024		/* some HCs can do less */
	unsigned		periodic_size;
	u32			*periodic;	/* hw periodic table */
	dma_addr_t		periodic_dma;
	unsigned		i_thresh;	/* uframes HC might cache */

	union ehci_shadow	*pshadow;	/* mirror hw periodic table */
	int			next_frame;	/* scan periodic, start here */
	unsigned		periodic_urbs;	/* how many urbs scheduled? */

	/* deferred work from IRQ, etc */
	struct tasklet_struct	tasklet;

	/* per root hub port */
	unsigned long		reset_done [EHCI_MAX_ROOT_PORTS];

	/* glue to PCI and HCD framework */
	struct usb_hcd		hcd;
	struct ehci_caps	*caps;
	struct ehci_regs	*regs;

	/* per-HC memory pools (could be per-PCI-bus, but ...) */
	struct pci_pool		*qh_pool;	/* qh per active urb */
	struct pci_pool		*qtd_pool;	/* one or more per qh */
	struct pci_pool		*itd_pool;	/* itd per iso urb */
	struct pci_pool		*sitd_pool;	/* sitd per split iso urb */
};

/* unwrap an HCD pointer to get an EHCI_HCD pointer */ 
#define hcd_to_ehci(hcd_ptr) list_entry(hcd_ptr, struct ehci_hcd, hcd)

/* NOTE:  urb->transfer_flags expected to not use this bit !!! */
#define EHCI_STATE_UNLINK	0x8000		/* urb being unlinked */

/*-------------------------------------------------------------------------*/

/* EHCI register interface, corresponds to EHCI Revision 0.95 specification */

/* Section 2.2 Host Controller Capability Registers */
struct ehci_caps {
	u8		length;		/* CAPLENGTH - size of this struct */
	u8		reserved;       /* offset 0x1 */
	u16		hci_version;    /* HCIVERSION - offset 0x2 */
	u32		hcs_params;     /* HCSPARAMS - offset 0x4 */
#define HCS_DEBUG_PORT(p)	(((p)>>20)&0xf)	/* bits 23:20, debug port? */
#define HCS_INDICATOR(p)	((p)&(1 << 16))	/* true: has port indicators */
#define HCS_N_CC(p)		(((p)>>12)&0xf)	/* bits 15:12, #companion HCs */
#define HCS_N_PCC(p)		(((p)>>8)&0xf)	/* bits 11:8, ports per CC */
#define HCS_PORTROUTED(p)	((p)&(1 << 7))	/* true: port routing */ 
#define HCS_PPC(p)		((p)&(1 << 4))	/* true: port power control */ 
#define HCS_N_PORTS(p)		(((p)>>0)&0xf)	/* bits 3:0, ports on HC */

	u32		hcc_params;      /* HCCPARAMS - offset 0x8 */
#define HCC_EXT_CAPS(p)		(((p)>>8)&0xff)	/* for pci extended caps */
#define HCC_ISOC_CACHE(p)       ((p)&(1 << 7))  /* true: can cache isoc frame */
#define HCC_ISOC_THRES(p)       (((p)>>4)&0x7)  /* bits 6:4, uframes cached */
#define HCC_CANPARK(p)		((p)&(1 << 2))  /* true: can park on async qh */
#define HCC_PGM_FRAMELISTLEN(p) ((p)&(1 << 1))  /* true: periodic_size changes*/
#define HCC_64BIT_ADDR(p)       ((p)&(1))       /* true: can use 64-bit addr */
	u8		portroute [8];	 /* nibbles for routing - offset 0xC */
} __attribute__ ((packed));


/* Section 2.3 Host Controller Operational Registers */
struct ehci_regs {

	/* USBCMD: offset 0x00 */
	u32		command;
/* 23:16 is r/w intr rate, in microframes; default "8" == 1/msec */
#define CMD_PARK	(1<<11)		/* enable "park" on async qh */
#define CMD_PARK_CNT(c)	(((c)>>8)&3)	/* how many transfers to park for */
#define CMD_LRESET	(1<<7)		/* partial reset (no ports, etc) */
#define CMD_IAAD	(1<<6)		/* "doorbell" interrupt async advance */
#define CMD_ASE		(1<<5)		/* async schedule enable */
#define CMD_PSE  	(1<<4)		/* periodic schedule enable */
/* 3:2 is periodic frame list size */
#define CMD_RESET	(1<<1)		/* reset HC not bus */
#define CMD_RUN		(1<<0)		/* start/stop HC */

	/* USBSTS: offset 0x04 */
	u32		status;
#define STS_ASS		(1<<15)		/* Async Schedule Status */
#define STS_PSS		(1<<14)		/* Periodic Schedule Status */
#define STS_RECL	(1<<13)		/* Reclamation */
#define STS_HALT	(1<<12)		/* Not running (any reason) */
/* some bits reserved */
	/* these STS_* flags are also intr_enable bits (USBINTR) */
#define STS_IAA		(1<<5)		/* Interrupted on async advance */
#define STS_FATAL	(1<<4)		/* such as some PCI access errors */
#define STS_FLR		(1<<3)		/* frame list rolled over */
#define STS_PCD		(1<<2)		/* port change detect */
#define STS_ERR		(1<<1)		/* "error" completion (overflow, ...) */
#define STS_INT		(1<<0)		/* "normal" completion (short, ...) */

	/* USBINTR: offset 0x08 */
	u32		intr_enable;

	/* FRINDEX: offset 0x0C */
	u32		frame_index;	/* current microframe number */
	/* CTRLDSSEGMENT: offset 0x10 */
	u32		segment; 	/* address bits 63:32 if needed */
	/* PERIODICLISTBASE: offset 0x14 */
	u32		frame_list; 	/* points to periodic list */
	/* ASYNCICLISTADDR: offset 0x18 */
	u32		async_next;	/* address of next async queue head */

	u32		reserved [9];

	/* CONFIGFLAG: offset 0x40 */
	u32		configured_flag;
#define FLAG_CF		(1<<0)		/* true: we'll support "high speed" */

	/* PORTSC: offset 0x44 */
	u32		port_status [0];	/* up to N_PORTS */
/* 31:23 reserved */
#define PORT_WKOC_E	(1<<22)		/* wake on overcurrent (enable) */
#define PORT_WKDISC_E	(1<<21)		/* wake on disconnect (enable) */
#define PORT_WKCONN_E	(1<<20)		/* wake on connect (enable) */
/* 19:16 for port testing */
/* 15:14 for using port indicator leds (if HCS_INDICATOR allows) */
#define PORT_OWNER	(1<<13)		/* true: companion hc owns this port */
#define PORT_POWER	(1<<12)		/* true: has power (see PPC) */
#define PORT_USB11(x) (((x)&(3<<10))==(1<<10))	/* USB 1.1 device */
/* 11:10 for detecting lowspeed devices (reset vs release ownership) */
/* 9 reserved */
#define PORT_RESET	(1<<8)		/* reset port */
#define PORT_SUSPEND	(1<<7)		/* suspend port */
#define PORT_RESUME	(1<<6)		/* resume it */
#define PORT_OCC	(1<<5)		/* over current change */
#define PORT_OC		(1<<4)		/* over current active */
#define PORT_PEC	(1<<3)		/* port enable change */
#define PORT_PE		(1<<2)		/* port enable */
#define PORT_CSC	(1<<1)		/* connect status change */
#define PORT_CONNECT	(1<<0)		/* device connected */
} __attribute__ ((packed));


/*-------------------------------------------------------------------------*/

#define	QTD_NEXT(dma)	cpu_to_le32((u32)dma)

/*
 * EHCI Specification 0.95 Section 3.5
 * QTD: describe data transfer components (buffer, direction, ...) 
 * See Fig 3-6 "Queue Element Transfer Descriptor Block Diagram".
 *
 * These are associated only with "QH" (Queue Head) structures,
 * used with control, bulk, and interrupt transfers.
 */
struct ehci_qtd {
	/* first part defined by EHCI spec */
	u32			hw_next;	  /* see EHCI 3.5.1 */
	u32			hw_alt_next;      /* see EHCI 3.5.2 */
	u32			hw_token;         /* see EHCI 3.5.3 */       
#define	QTD_TOGGLE	(1 << 31)	/* data toggle */
#define	QTD_LENGTH(tok)	(((tok)>>16) & 0x7fff)
#define	QTD_IOC		(1 << 15)	/* interrupt on complete */
#define	QTD_CERR(tok)	(((tok)>>10) & 0x3)
#define	QTD_PID(tok)	(((tok)>>8) & 0x3)
#define	QTD_STS_ACTIVE	(1 << 7)	/* HC may execute this */
#define	QTD_STS_HALT	(1 << 6)	/* halted on error */
#define	QTD_STS_DBE	(1 << 5)	/* data buffer error (in HC) */
#define	QTD_STS_BABBLE	(1 << 4)	/* device was babbling (qtd halted) */
#define	QTD_STS_XACT	(1 << 3)	/* device gave illegal response */
#define	QTD_STS_MMF	(1 << 2)	/* incomplete split transaction */
#define	QTD_STS_STS	(1 << 1)	/* split transaction state */
#define	QTD_STS_PING	(1 << 0)	/* issue PING? */
	u32			hw_buf [5];        /* see EHCI 3.5.4 */
	u32			hw_buf_hi [5];        /* Appendix B */

	/* the rest is HCD-private */
	dma_addr_t		qtd_dma;		/* qtd address */
	struct list_head	qtd_list;		/* sw qtd list */

	/* dma same in urb's qtds, except 1st control qtd (setup buffer) */
	struct urb		*urb;			/* qtd's urb */
	dma_addr_t		buf_dma;		/* buffer address */
	size_t			length;			/* length of buffer */
} __attribute__ ((aligned (32)));

/*-------------------------------------------------------------------------*/

/* type tag from {qh,itd,sitd,fstn}->hw_next */
#define Q_NEXT_TYPE(dma) ((dma) & __constant_cpu_to_le32 (3 << 1))

/* values for that type tag */
#define Q_TYPE_ITD	__constant_cpu_to_le32 (0 << 1)
#define Q_TYPE_QH	__constant_cpu_to_le32 (1 << 1)
#define Q_TYPE_SITD 	__constant_cpu_to_le32 (2 << 1)
#define Q_TYPE_FSTN 	__constant_cpu_to_le32 (3 << 1)

/* next async queue entry, or pointer to interrupt/periodic QH */
#define	QH_NEXT(dma)	(cpu_to_le32(((u32)dma)&~0x01f)|Q_TYPE_QH)

/* for periodic/async schedules and qtd lists, mark end of list */
#define	EHCI_LIST_END	__constant_cpu_to_le32(1) /* "null pointer" to hw */

/*
 * Entries in periodic shadow table are pointers to one of four kinds
 * of data structure.  That's dictated by the hardware; a type tag is
 * encoded in the low bits of the hardware's periodic schedule.  Use
 * Q_NEXT_TYPE to get the tag.
 *
 * For entries in the async schedule, the type tag always says "qh".
 */
union ehci_shadow {
	struct ehci_qh 		*qh;		/* Q_TYPE_QH */
	struct ehci_itd		*itd;		/* Q_TYPE_ITD */
	struct ehci_sitd	*sitd;		/* Q_TYPE_SITD */
	struct ehci_fstn	*fstn;		/* Q_TYPE_FSTN */
	void			*ptr;
};

/*-------------------------------------------------------------------------*/

/*
 * EHCI Specification 0.95 Section 3.6
 * QH: describes control/bulk/interrupt endpoints
 * See Fig 3-7 "Queue Head Structure Layout".
 *
 * These appear in both the async and (for interrupt) periodic schedules.
 */

struct ehci_qh {
	/* first part defined by EHCI spec */
	u32			hw_next;	 /* see EHCI 3.6.1 */
	u32			hw_info1;        /* see EHCI 3.6.2 */
#define	QH_HEAD		0x00008000
	u32			hw_info2;        /* see EHCI 3.6.2 */
	u32			hw_current;	 /* qtd list - see EHCI 3.6.4 */
	
	/* qtd overlay (hardware parts of a struct ehci_qtd) */
	u32			hw_qtd_next;
	u32			hw_alt_next;
	u32			hw_token;
	u32			hw_buf [5];
	u32			hw_buf_hi [5];

	/* the rest is HCD-private */
	dma_addr_t		qh_dma;		/* address of qh */
	union ehci_shadow	qh_next;	/* ptr to qh; or periodic */
	struct list_head	qtd_list;	/* sw qtd list */

	atomic_t		refcount;
	unsigned short		usecs;		/* intr bandwidth */
	short			qh_state;
#define	QH_STATE_LINKED		1		/* HC sees this */
#define	QH_STATE_UNLINK		2		/* HC may still see this */
#define	QH_STATE_IDLE		3		/* HC doesn't see this */

#ifdef EHCI_SOFT_RETRIES
	int			retries;
#endif
} __attribute__ ((aligned (32)));

/*-------------------------------------------------------------------------*/

/*
 * EHCI Specification 0.95 Section 3.3
 * Fig 3-4 "Isochronous Transaction Descriptor (iTD)"
 *
 * Schedule records for high speed iso xfers
 */
struct ehci_itd {
	/* first part defined by EHCI spec */
	u32			hw_next;           /* see EHCI 3.3.1 */
	u32			hw_transaction [8]; /* see EHCI 3.3.2 */
#define EHCI_ISOC_ACTIVE        (1<<31)        /* activate transfer this slot */
#define EHCI_ISOC_BUF_ERR       (1<<30)        /* Data buffer error */
#define EHCI_ISOC_BABBLE        (1<<29)        /* babble detected */
#define EHCI_ISOC_XACTERR       (1<<28)        /* XactErr - transaction error */
#define	EHCI_ITD_LENGTH(tok)	(((tok)>>16) & 0x7fff)
#define	EHCI_ITD_IOC		(1 << 15)	/* interrupt on complete */

	u32			hw_bufp [7];	/* see EHCI 3.3.3 */ 
	u32			hw_bufp_hi [7];	/* Appendix B */

	/* the rest is HCD-private */
	dma_addr_t		itd_dma;	/* for this itd */
	union ehci_shadow	itd_next;	/* ptr to periodic q entry */

	struct urb		*urb;
	unsigned		index;		/* in urb->iso_frame_desc */
	struct list_head	itd_list;	/* list of urb frames' itds */
	dma_addr_t		buf_dma;	/* frame's buffer address */

	unsigned		uframe;		/* in periodic schedule */
	u32			transaction [8]; /* copy of hw_transaction */

} __attribute__ ((aligned (32)));

/*-------------------------------------------------------------------------*/

/*
 * EHCI Specification 0.95 Section 3.4 
 * siTD, aka split-transaction isochronous Transfer Descriptor
 *       ... describe low/full speed iso xfers through TT in hubs
 * see Figure 3-5 "Split-transaction Isochronous Transaction Descriptor (siTD)
 */
struct ehci_sitd {
	/* first part defined by EHCI spec */
	u32			hw_next;
/* uses bit field macros above - see EHCI 0.95 Table 3-8 */
	u32			hw_fullspeed_ep;  /* see EHCI table 3-9 */
	u32                     hw_uframe;        /* see EHCI table 3-10 */
        u32                     hw_tx_results1;   /* see EHCI table 3-11 */
	u32                     hw_tx_results2;   /* see EHCI table 3-12 */
	u32                     hw_tx_results3;   /* see EHCI table 3-12 */
        u32                     hw_backpointer;   /* see EHCI table 3-13 */
	u32			hw_buf_hi [2];	  /* Appendix B */

	/* the rest is HCD-private */
	dma_addr_t		sitd_dma;
	union ehci_shadow	sitd_next;	/* ptr to periodic q entry */
	struct urb		*urb;
	dma_addr_t		buf_dma;	/* buffer address */
} __attribute__ ((aligned (32)));

/*-------------------------------------------------------------------------*/

/*
 * EHCI Specification 0.96 Section 3.7
 * Periodic Frame Span Traversal Node (FSTN)
 *
 * Manages split interrupt transactions (using TT) that span frame boundaries
 * into uframes 0/1; see 4.12.2.2.  In those uframes, a "save place" FSTN
 * makes the HC jump (back) to a QH to scan for fs/ls QH completions until
 * it hits a "restore" FSTN; then it returns to finish other uframe 0/1 work.
 */
struct ehci_fstn {
	u32			hw_next;	/* any periodic q entry */
	u32			hw_prev;	/* qh or EHCI_LIST_END */

	/* the rest is HCD-private */
	dma_addr_t		fstn_dma;
	union ehci_shadow	fstn_next;	/* ptr to periodic q entry */
} __attribute__ ((aligned (32)));

#endif /* __LINUX_EHCI_HCD_H */