[deliverable/linux.git] / drivers / net / enic / vnic_rq.h

/*
 * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
 * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
 *
 * This program is free software; you may redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * 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.
 *
 */

#ifndef _VNIC_RQ_H_
#define _VNIC_RQ_H_

#include <linux/pci.h>

#include "vnic_dev.h"
#include "vnic_cq.h"

/* Receive queue control */
struct vnic_rq_ctrl {
	u64 ring_base;			/* 0x00 */
	u32 ring_size;			/* 0x08 */
	u32 pad0;
	u32 posted_index;		/* 0x10 */
	u32 pad1;
	u32 cq_index;			/* 0x18 */
	u32 pad2;
	u32 enable;			/* 0x20 */
	u32 pad3;
	u32 running;			/* 0x28 */
	u32 pad4;
	u32 fetch_index;		/* 0x30 */
	u32 pad5;
	u32 error_interrupt_enable;	/* 0x38 */
	u32 pad6;
	u32 error_interrupt_offset;	/* 0x40 */
	u32 pad7;
	u32 error_status;		/* 0x48 */
	u32 pad8;
	u32 dropped_packet_count;	/* 0x50 */
	u32 pad9;
	u32 dropped_packet_count_rc;	/* 0x58 */
	u32 pad10;
};

/* Break the vnic_rq_buf allocations into blocks of 64 entries */
#define VNIC_RQ_BUF_BLK_ENTRIES 64
#define VNIC_RQ_BUF_BLK_SZ \
	(VNIC_RQ_BUF_BLK_ENTRIES * sizeof(struct vnic_rq_buf))
#define VNIC_RQ_BUF_BLKS_NEEDED(entries) \
	DIV_ROUND_UP(entries, VNIC_RQ_BUF_BLK_ENTRIES)
#define VNIC_RQ_BUF_BLKS_MAX VNIC_RQ_BUF_BLKS_NEEDED(4096)

struct vnic_rq_buf {
	struct vnic_rq_buf *next;
	dma_addr_t dma_addr;
	void *os_buf;
	unsigned int os_buf_index;
	unsigned int len;
	unsigned int index;
	void *desc;
};

struct vnic_rq {
	unsigned int index;
	struct vnic_dev *vdev;
	struct vnic_rq_ctrl __iomem *ctrl;              /* memory-mapped */
	struct vnic_dev_ring ring;
	struct vnic_rq_buf *bufs[VNIC_RQ_BUF_BLKS_MAX];
	struct vnic_rq_buf *to_use;
	struct vnic_rq_buf *to_clean;
	void *os_buf_head;
	unsigned int buf_index;
	unsigned int pkts_outstanding;
};

static inline unsigned int vnic_rq_desc_avail(struct vnic_rq *rq)
{
	/* how many does SW own? */
	return rq->ring.desc_avail;
}

static inline unsigned int vnic_rq_desc_used(struct vnic_rq *rq)
{
	/* how many does HW own? */
	return rq->ring.desc_count - rq->ring.desc_avail - 1;
}

static inline void *vnic_rq_next_desc(struct vnic_rq *rq)
{
	return rq->to_use->desc;
}

static inline unsigned int vnic_rq_next_index(struct vnic_rq *rq)
{
	return rq->to_use->index;
}

static inline unsigned int vnic_rq_next_buf_index(struct vnic_rq *rq)
{
	return rq->buf_index++;
}

static inline void vnic_rq_post(struct vnic_rq *rq,
	void *os_buf, unsigned int os_buf_index,
	dma_addr_t dma_addr, unsigned int len)
{
	struct vnic_rq_buf *buf = rq->to_use;

	buf->os_buf = os_buf;
	buf->os_buf_index = os_buf_index;
	buf->dma_addr = dma_addr;
	buf->len = len;

	buf = buf->next;
	rq->to_use = buf;
	rq->ring.desc_avail--;

	/* Move the posted_index every nth descriptor
	 */

#ifndef VNIC_RQ_RETURN_RATE
#define VNIC_RQ_RETURN_RATE		0xf	/* keep 2^n - 1 */
#endif

	if ((buf->index & VNIC_RQ_RETURN_RATE) == 0) {
		/* Adding write memory barrier prevents compiler and/or CPU
		 * reordering, thus avoiding descriptor posting before
		 * descriptor is initialized. Otherwise, hardware can read
		 * stale descriptor fields.
		 */
		wmb();
		iowrite32(buf->index, &rq->ctrl->posted_index);
	}
}

static inline int vnic_rq_posting_soon(struct vnic_rq *rq)
{
	return ((rq->to_use->index & VNIC_RQ_RETURN_RATE) == 0);
}

static inline void vnic_rq_return_descs(struct vnic_rq *rq, unsigned int count)
{
	rq->ring.desc_avail += count;
}

enum desc_return_options {
	VNIC_RQ_RETURN_DESC,
	VNIC_RQ_DEFER_RETURN_DESC,
};

static inline void vnic_rq_service(struct vnic_rq *rq,
	struct cq_desc *cq_desc, u16 completed_index,
	int desc_return, void (*buf_service)(struct vnic_rq *rq,
	struct cq_desc *cq_desc, struct vnic_rq_buf *buf,
	int skipped, void *opaque), void *opaque)
{
	struct vnic_rq_buf *buf;
	int skipped;

	buf = rq->to_clean;
	while (1) {

		skipped = (buf->index != completed_index);

		(*buf_service)(rq, cq_desc, buf, skipped, opaque);

		if (desc_return == VNIC_RQ_RETURN_DESC)
			rq->ring.desc_avail++;

		rq->to_clean = buf->next;

		if (!skipped)
			break;

		buf = rq->to_clean;
	}
}

static inline int vnic_rq_fill(struct vnic_rq *rq,
	int (*buf_fill)(struct vnic_rq *rq))
{
	int err;

	while (vnic_rq_desc_avail(rq) > 0) {

		err = (*buf_fill)(rq);
		if (err)
			return err;
	}

	return 0;
}

void vnic_rq_free(struct vnic_rq *rq);
int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
	unsigned int desc_count, unsigned int desc_size);
void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
	unsigned int error_interrupt_enable,
	unsigned int error_interrupt_offset);
unsigned int vnic_rq_error_status(struct vnic_rq *rq);
void vnic_rq_enable(struct vnic_rq *rq);
int vnic_rq_disable(struct vnic_rq *rq);
void vnic_rq_clean(struct vnic_rq *rq,
	void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf));

#endif /* _VNIC_RQ_H_ */
Commit	Line	Data
01f2e4ea SF	1	/*
	2	* Copyright 2008 Cisco Systems, Inc. All rights reserved.
	3	* Copyright 2007 Nuova Systems, Inc. All rights reserved.
	4	*
	5	* This program is free software; you may redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation; version 2 of the License.
	8	*
	9	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	10	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	11	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	12	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	13	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	14	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	15	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	16	* SOFTWARE.
	17	*
	18	*/
	19
	20	#ifndef _VNIC_RQ_H_
	21	#define _VNIC_RQ_H_
	22
	23	#include <linux/pci.h>
	24
	25	#include "vnic_dev.h"
	26	#include "vnic_cq.h"
	27
	28	/* Receive queue control */
	29	struct vnic_rq_ctrl {
	30	u64 ring_base; /* 0x00 */
	31	u32 ring_size; /* 0x08 */
	32	u32 pad0;
	33	u32 posted_index; /* 0x10 */
	34	u32 pad1;
	35	u32 cq_index; /* 0x18 */
	36	u32 pad2;
	37	u32 enable; /* 0x20 */
	38	u32 pad3;
	39	u32 running; /* 0x28 */
	40	u32 pad4;
	41	u32 fetch_index; /* 0x30 */
	42	u32 pad5;
	43	u32 error_interrupt_enable; /* 0x38 */
	44	u32 pad6;
	45	u32 error_interrupt_offset; /* 0x40 */
	46	u32 pad7;
	47	u32 error_status; /* 0x48 */
	48	u32 pad8;
	49	u32 dropped_packet_count; /* 0x50 */
	50	u32 pad9;
	51	u32 dropped_packet_count_rc; /* 0x58 */
	52	u32 pad10;
	53	};
	54
	55	/* Break the vnic_rq_buf allocations into blocks of 64 entries */
	56	#define VNIC_RQ_BUF_BLK_ENTRIES 64
	57	#define VNIC_RQ_BUF_BLK_SZ \
	58	(VNIC_RQ_BUF_BLK_ENTRIES * sizeof(struct vnic_rq_buf))
	59	#define VNIC_RQ_BUF_BLKS_NEEDED(entries) \
	60	DIV_ROUND_UP(entries, VNIC_RQ_BUF_BLK_ENTRIES)
	61	#define VNIC_RQ_BUF_BLKS_MAX VNIC_RQ_BUF_BLKS_NEEDED(4096)
	62
	63	struct vnic_rq_buf {
	64	struct vnic_rq_buf *next;
65	dma_addr_t dma_addr;
66	void *os_buf;
67	unsigned int os_buf_index;
68	unsigned int len;
69	unsigned int index;
70	void *desc;
71	};
72
73	struct vnic_rq {
74	unsigned int index;
75	struct vnic_dev *vdev;
76	struct vnic_rq_ctrl __iomem ctrl; / memory-mapped */
77	struct vnic_dev_ring ring;
78	struct vnic_rq_buf *bufs[VNIC_RQ_BUF_BLKS_MAX];
79	struct vnic_rq_buf *to_use;
80	struct vnic_rq_buf *to_clean;
81	void *os_buf_head;
82	unsigned int buf_index;
83	unsigned int pkts_outstanding;
84	};
85
86	static inline unsigned int vnic_rq_desc_avail(struct vnic_rq *rq)
87	{
88	/* how many does SW own? */
89	return rq->ring.desc_avail;
90	}
91
92	static inline unsigned int vnic_rq_desc_used(struct vnic_rq *rq)
93	{
94	/* how many does HW own? */
95	return rq->ring.desc_count - rq->ring.desc_avail - 1;
96	}
97
98	static inline void vnic_rq_next_desc(struct vnic_rq rq)
99	{
100	return rq->to_use->desc;
101	}
102
103	static inline unsigned int vnic_rq_next_index(struct vnic_rq *rq)
104	{
105	return rq->to_use->index;
106	}
107
108	static inline unsigned int vnic_rq_next_buf_index(struct vnic_rq *rq)
109	{
110	return rq->buf_index++;
111	}
112
113	static inline void vnic_rq_post(struct vnic_rq *rq,
114	void *os_buf, unsigned int os_buf_index,
115	dma_addr_t dma_addr, unsigned int len)
116	{
117	struct vnic_rq_buf *buf = rq->to_use;
118
119	buf->os_buf = os_buf;
120	buf->os_buf_index = os_buf_index;
121	buf->dma_addr = dma_addr;
122	buf->len = len;
123
124	buf = buf->next;
125	rq->to_use = buf;
126	rq->ring.desc_avail--;
127
128	/* Move the posted_index every nth descriptor
129	*/
130
131	#ifndef VNIC_RQ_RETURN_RATE
132	#define VNIC_RQ_RETURN_RATE 0xf /* keep 2^n - 1 */
133	#endif
134
84596451 SF	135	if ((buf->index & VNIC_RQ_RETURN_RATE) == 0) {
	136	/* Adding write memory barrier prevents compiler and/or CPU
	137	* reordering, thus avoiding descriptor posting before
	138	* descriptor is initialized. Otherwise, hardware can read
	139	* stale descriptor fields.
	140	*/
	141	wmb();
01f2e4ea	142	iowrite32(buf->index, &rq->ctrl->posted_index);
84596451	143	}
01f2e4ea SF	144	}
01f2e4ea SF	145
4badc385 SF	146	static inline int vnic_rq_posting_soon(struct vnic_rq *rq)
	147	{
	148	return ((rq->to_use->index & VNIC_RQ_RETURN_RATE) == 0);
	149	}
	150
01f2e4ea SF	151	static inline void vnic_rq_return_descs(struct vnic_rq *rq, unsigned int count)
	152	{
	153	rq->ring.desc_avail += count;
	154	}
	155
	156	enum desc_return_options {
	157	VNIC_RQ_RETURN_DESC,
	158	VNIC_RQ_DEFER_RETURN_DESC,
	159	};
	160
	161	static inline void vnic_rq_service(struct vnic_rq *rq,
	162	struct cq_desc *cq_desc, u16 completed_index,
	163	int desc_return, void (buf_service)(struct vnic_rq rq,
	164	struct cq_desc cq_desc, struct vnic_rq_buf buf,
	165	int skipped, void opaque), void opaque)
	166	{
	167	struct vnic_rq_buf *buf;
	168	int skipped;
	169
	170	buf = rq->to_clean;
	171	while (1) {
	172
	173	skipped = (buf->index != completed_index);
	174
	175	(*buf_service)(rq, cq_desc, buf, skipped, opaque);
	176
	177	if (desc_return == VNIC_RQ_RETURN_DESC)
	178	rq->ring.desc_avail++;
	179
	180	rq->to_clean = buf->next;
	181
	182	if (!skipped)
	183	break;
	184
	185	buf = rq->to_clean;
	186	}
	187	}
	188
	189	static inline int vnic_rq_fill(struct vnic_rq *rq,
	190	int (buf_fill)(struct vnic_rq rq))
	191	{
	192	int err;
	193
4badc385	194	while (vnic_rq_desc_avail(rq) > 0) {
01f2e4ea SF	195
	196	err = (*buf_fill)(rq);
	197	if (err)
	198	return err;
	199	}
	200
	201	return 0;
	202	}
	203
	204	void vnic_rq_free(struct vnic_rq *rq);
	205	int vnic_rq_alloc(struct vnic_dev vdev, struct vnic_rq rq, unsigned int index,
	206	unsigned int desc_count, unsigned int desc_size);
	207	void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
	208	unsigned int error_interrupt_enable,
	209	unsigned int error_interrupt_offset);
	210	unsigned int vnic_rq_error_status(struct vnic_rq *rq);
	211	void vnic_rq_enable(struct vnic_rq *rq);
	212	int vnic_rq_disable(struct vnic_rq *rq);
	213	void vnic_rq_clean(struct vnic_rq *rq,
	214	void (buf_clean)(struct vnic_rq rq, struct vnic_rq_buf *buf));
	215
	216	#endif /* _VNIC_RQ_H_ */