[SCSI] fnic: Add new Cisco PCI-Express FCoE HBA

fnic is a driver for the Cisco PCI-Express FCoE HBA

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 235 insertions, 0 deletions

diff --git a/drivers/scsi/fnic/vnic_rq.h b/drivers/scsi/fnic/vnic_rq.h
new file mode 100644
index 00000000000..aebdfbd6ad3
--- /dev/null
+++ b/drivers/scsi/fnic/vnic_rq.h
@@ -0,0 +1,235 @@
+/*
+ * 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"
+
+/*
+ * These defines avoid symbol clash between fnic and enic (Cisco 10G Eth
+ * Driver) when both are built with CONFIG options =y
+ */
+#define vnic_rq_desc_avail fnic_rq_desc_avail
+#define vnic_rq_desc_used fnic_rq_desc_used
+#define vnic_rq_next_desc fnic_rq_next_desc
+#define vnic_rq_next_index fnic_rq_next_index
+#define vnic_rq_next_buf_index fnic_rq_next_buf_index
+#define vnic_rq_post fnic_rq_post
+#define vnic_rq_posting_soon fnic_rq_posting_soon
+#define vnic_rq_return_descs fnic_rq_return_descs
+#define vnic_rq_service fnic_rq_service
+#define vnic_rq_fill fnic_rq_fill
+#define vnic_rq_free fnic_rq_free
+#define vnic_rq_alloc fnic_rq_alloc
+#define vnic_rq_init fnic_rq_init
+#define vnic_rq_error_status fnic_rq_error_status
+#define vnic_rq_enable fnic_rq_enable
+#define vnic_rq_disable fnic_rq_disable
+#define vnic_rq_clean fnic_rq_clean
+
+/* 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) > 1) {
+
+		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_ */