19c067b84SDoug Ambrisko /* SPDX-License-Identifier: BSD-3-Clause
29c067b84SDoug Ambrisko * Copyright 2008-2017 Cisco Systems, Inc. All rights reserved.
39c067b84SDoug Ambrisko * Copyright 2007 Nuova Systems, Inc. All rights reserved.
49c067b84SDoug Ambrisko */
59c067b84SDoug Ambrisko
69c067b84SDoug Ambrisko #ifndef _CQ_DESC_H_
79c067b84SDoug Ambrisko #define _CQ_DESC_H_
89c067b84SDoug Ambrisko
99c067b84SDoug Ambrisko /*
109c067b84SDoug Ambrisko * Completion queue descriptor types
119c067b84SDoug Ambrisko */
129c067b84SDoug Ambrisko enum cq_desc_types {
139c067b84SDoug Ambrisko CQ_DESC_TYPE_WQ_ENET = 0,
149c067b84SDoug Ambrisko CQ_DESC_TYPE_DESC_COPY = 1,
159c067b84SDoug Ambrisko CQ_DESC_TYPE_WQ_EXCH = 2,
169c067b84SDoug Ambrisko CQ_DESC_TYPE_RQ_ENET = 3,
179c067b84SDoug Ambrisko CQ_DESC_TYPE_RQ_FCP = 4,
189c067b84SDoug Ambrisko CQ_DESC_TYPE_IOMMU_MISS = 5,
199c067b84SDoug Ambrisko CQ_DESC_TYPE_SGL = 6,
209c067b84SDoug Ambrisko CQ_DESC_TYPE_CLASSIFIER = 7,
219c067b84SDoug Ambrisko CQ_DESC_TYPE_TEST = 127,
229c067b84SDoug Ambrisko };
239c067b84SDoug Ambrisko
249c067b84SDoug Ambrisko /* Completion queue descriptor: 16B
259c067b84SDoug Ambrisko *
269c067b84SDoug Ambrisko * All completion queues have this basic layout. The
279c067b84SDoug Ambrisko * type_specfic area is unique for each completion
289c067b84SDoug Ambrisko * queue type.
299c067b84SDoug Ambrisko */
309c067b84SDoug Ambrisko struct cq_desc {
319c067b84SDoug Ambrisko __le16 completed_index;
329c067b84SDoug Ambrisko __le16 q_number;
339c067b84SDoug Ambrisko u8 type_specfic[11];
349c067b84SDoug Ambrisko u8 type_color;
359c067b84SDoug Ambrisko };
369c067b84SDoug Ambrisko
379c067b84SDoug Ambrisko #define CQ_DESC_TYPE_BITS 4
389c067b84SDoug Ambrisko #define CQ_DESC_TYPE_MASK ((1 << CQ_DESC_TYPE_BITS) - 1)
399c067b84SDoug Ambrisko #define CQ_DESC_COLOR_MASK 1
409c067b84SDoug Ambrisko #define CQ_DESC_COLOR_SHIFT 7
419c067b84SDoug Ambrisko #define CQ_DESC_COLOR_MASK_NOSHIFT 0x80
429c067b84SDoug Ambrisko #define CQ_DESC_Q_NUM_BITS 10
439c067b84SDoug Ambrisko #define CQ_DESC_Q_NUM_MASK ((1 << CQ_DESC_Q_NUM_BITS) - 1)
449c067b84SDoug Ambrisko #define CQ_DESC_COMP_NDX_BITS 12
459c067b84SDoug Ambrisko #define CQ_DESC_COMP_NDX_MASK ((1 << CQ_DESC_COMP_NDX_BITS) - 1)
469c067b84SDoug Ambrisko
cq_color_enc(struct cq_desc * desc,const u8 color)479c067b84SDoug Ambrisko static inline void cq_color_enc(struct cq_desc *desc, const u8 color)
489c067b84SDoug Ambrisko {
499c067b84SDoug Ambrisko if (color)
509c067b84SDoug Ambrisko desc->type_color |= (1 << CQ_DESC_COLOR_SHIFT);
519c067b84SDoug Ambrisko else
529c067b84SDoug Ambrisko desc->type_color &= ~(1 << CQ_DESC_COLOR_SHIFT);
539c067b84SDoug Ambrisko }
549c067b84SDoug Ambrisko
cq_desc_enc(struct cq_desc * desc,const u8 type,const u8 color,const u16 q_number,const u16 completed_index)559c067b84SDoug Ambrisko static inline void cq_desc_enc(struct cq_desc *desc,
569c067b84SDoug Ambrisko const u8 type, const u8 color, const u16 q_number,
579c067b84SDoug Ambrisko const u16 completed_index)
589c067b84SDoug Ambrisko {
599c067b84SDoug Ambrisko desc->type_color = (type & CQ_DESC_TYPE_MASK) |
609c067b84SDoug Ambrisko ((color & CQ_DESC_COLOR_MASK) << CQ_DESC_COLOR_SHIFT);
619c067b84SDoug Ambrisko desc->q_number = cpu_to_le16(q_number & CQ_DESC_Q_NUM_MASK);
629c067b84SDoug Ambrisko desc->completed_index = cpu_to_le16(completed_index &
639c067b84SDoug Ambrisko CQ_DESC_COMP_NDX_MASK);
649c067b84SDoug Ambrisko }
659c067b84SDoug Ambrisko
cq_desc_dec(const struct cq_desc * desc_arg,u8 * type,u8 * color,u16 * q_number,u16 * completed_index)669c067b84SDoug Ambrisko static inline void cq_desc_dec(const struct cq_desc *desc_arg,
679c067b84SDoug Ambrisko u8 *type, u8 *color, u16 *q_number, u16 *completed_index)
689c067b84SDoug Ambrisko {
699c067b84SDoug Ambrisko const struct cq_desc *desc = desc_arg;
709c067b84SDoug Ambrisko const u8 type_color = desc->type_color;
719c067b84SDoug Ambrisko
729c067b84SDoug Ambrisko *color = (type_color >> CQ_DESC_COLOR_SHIFT) & CQ_DESC_COLOR_MASK;
739c067b84SDoug Ambrisko
749c067b84SDoug Ambrisko /*
759c067b84SDoug Ambrisko * Make sure color bit is read from desc *before* other fields
769c067b84SDoug Ambrisko * are read from desc. Hardware guarantees color bit is last
779c067b84SDoug Ambrisko * bit (byte) written. Adding the rmb() prevents the compiler
789c067b84SDoug Ambrisko * and/or CPU from reordering the reads which would potentially
799c067b84SDoug Ambrisko * result in reading stale values.
809c067b84SDoug Ambrisko */
819c067b84SDoug Ambrisko
829c067b84SDoug Ambrisko rmb();
839c067b84SDoug Ambrisko
849c067b84SDoug Ambrisko *type = type_color & CQ_DESC_TYPE_MASK;
859c067b84SDoug Ambrisko *q_number = le16_to_cpu(desc->q_number) & CQ_DESC_Q_NUM_MASK;
869c067b84SDoug Ambrisko *completed_index = le16_to_cpu(desc->completed_index) &
879c067b84SDoug Ambrisko CQ_DESC_COMP_NDX_MASK;
889c067b84SDoug Ambrisko }
899c067b84SDoug Ambrisko
cq_color_dec(const struct cq_desc * desc_arg,u8 * color)909c067b84SDoug Ambrisko static inline void cq_color_dec(const struct cq_desc *desc_arg, u8 *color)
919c067b84SDoug Ambrisko {
929c067b84SDoug Ambrisko volatile const struct cq_desc *desc = desc_arg;
939c067b84SDoug Ambrisko
949c067b84SDoug Ambrisko *color = (desc->type_color >> CQ_DESC_COLOR_SHIFT) & CQ_DESC_COLOR_MASK;
959c067b84SDoug Ambrisko }
969c067b84SDoug Ambrisko
979c067b84SDoug Ambrisko #endif /* _CQ_DESC_H_ */
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