Re: [PATCH v3 4/9] bus: fsl-mc: dpio: add frame descriptor and scatter/gather APIs

[Laurentiu Tudor <laurentiu.tudor@nxp.com>]

Some more bits and pieces inside.

---
Best Regards, Laurentiu

On 12/02/2016 12:41 AM, Stuart Yoder wrote:
> From: Roy Pledge <Roy.Pledge@nxp.com>
> 
> Add global definitions for DPAA2 frame descriptors and scatter
> gather entries.
> 
> Signed-off-by: Roy Pledge <Roy.Pledge@nxp.com>
> Signed-off-by: Stuart Yoder <stuart.yoder@nxp.com>
> ---
> 
> Notes:
>     -v3
>        -no changes
>     -v2
>        -added setter/getter for the FD ctrl field
>        -corrected comment for SG format_offset field description
>        -added support for short length field in FD
> 
>  include/linux/fsl/dpaa2-fd.h | 448 +++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 448 insertions(+)
>  create mode 100644 include/linux/fsl/dpaa2-fd.h
> 
> diff --git a/include/linux/fsl/dpaa2-fd.h b/include/linux/fsl/dpaa2-fd.h
> new file mode 100644
> index 0000000..182c8f4
> --- /dev/null
> +++ b/include/linux/fsl/dpaa2-fd.h
> @@ -0,0 +1,448 @@
> +/*
> + * Copyright 2014-2016 Freescale Semiconductor Inc.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions are met:
> + *     * Redistributions of source code must retain the above copyright
> + *       notice, this list of conditions and the following disclaimer.
> + *     * Redistributions in binary form must reproduce the above copyright
> + *       notice, this list of conditions and the following disclaimer in the
> + *       documentation and/or other materials provided with the distribution.
> + *     * Neither the name of Freescale Semiconductor nor the
> + *       names of its contributors may be used to endorse or promote products
> + *       derived from this software without specific prior written permission.
> + *
> + * ALTERNATIVELY, this software may be distributed under the terms of the
> + * GNU General Public License ("GPL") as published by the Free Software
> + * Foundation, either version 2 of that License or (at your option) any
> + * later version.
> + *
> + * THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY
> + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
> + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
> + * DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY
> + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
> + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
> + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
> + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
> + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +#ifndef __FSL_DPAA2_FD_H
> +#define __FSL_DPAA2_FD_H
> +
> +#include <linux/kernel.h>
> +
> +/**
> + * DOC: DPAA2 FD - Frame Descriptor APIs for DPAA2
> + *
> + * Frame Descriptors (FDs) are used to describe frame data in the DPAA2.
> + * Frames can be enqueued and dequeued to Frame Queues (FQs) which are consumed
> + * by the various DPAA accelerators (WRIOP, SEC, PME, DCE)
> + *
> + * There are three types of frames: single, scatter gather, and frame lists.
> + *
> + * The set of APIs in this file must be used to create, manipulate and
> + * query Frame Descriptors.
> + */
> +
> +/**
> + * struct dpaa2_fd - Struct describing FDs
> + * @words:         for easier/faster copying the whole FD structure
> + * @addr:          address in the FD
> + * @len:           length in the FD
> + * @bpid:          buffer pool ID
> + * @format_offset: format, offset, and short-length fields
> + * @frc:           frame context
> + * @ctrl:          control bits...including dd, sc, va, err, etc
> + * @flc:           flow context address
> + *
> + * This structure represents the basic Frame Descriptor used in the system.
> + */
> +struct dpaa2_fd {
> +	union {
> +		u32 words[8];
> +		struct dpaa2_fd_simple {
> +			__le64 addr;
> +			__le32 len;
> +			__le16 bpid;
> +			__le16 format_offset;
> +			__le32 frc;
> +			__le32 ctrl;
> +			__le64 flc;
> +		} simple;
> +	};
> +};
> +
> +#define FD_SHORT_LEN_FLAG_MASK 0x1
> +#define FD_SHORT_LEN_FLAG_SHIFT 14
> +#define FD_SHORT_LEN_MASK 0x1FFFF
> +#define FD_OFFSET_MASK 0x0FFF
> +#define FD_FORMAT_MASK 0x3
> +#define FD_FORMAT_SHIFT 12
> +#define SG_SHORT_LEN_FLAG_MASK 0x1
> +#define SG_SHORT_LEN_FLAG_SHIFT 14
> +#define SG_SHORT_LEN_MASK 0x1FFFF
> +#define SG_OFFSET_MASK 0x0FFF
> +#define SG_FORMAT_MASK 0x3
> +#define SG_FORMAT_SHIFT 12
> +#define SG_BPID_MASK 0x3FFF
> +#define SG_FINAL_FLAG_MASK 0x1
> +#define SG_FINAL_FLAG_SHIFT 15

We should align the values of these macros as we do in other places.

> +enum dpaa2_fd_format {
> +	dpaa2_fd_single = 0,
> +	dpaa2_fd_list,
> +	dpaa2_fd_sg
> +};
> +
> +/**
> + * dpaa2_fd_get_addr() - get the addr field of frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the address in the frame descriptor.
> + */
> +static inline dma_addr_t dpaa2_fd_get_addr(const struct dpaa2_fd *fd)
> +{
> +

Extra empty line.

> +	return (dma_addr_t)fd->simple.addr;
> +}
> +
> +/**
> + * dpaa2_fd_set_addr() - Set the addr field of frame descriptor
> + * @fd: the given frame descriptor
> + * @addr: the address needs to be set in frame descriptor
> + */
> +static inline void dpaa2_fd_set_addr(struct dpaa2_fd *fd, dma_addr_t addr)
> +{
> +	fd->simple.addr = addr;
> +}
> +
> +/**
> + * dpaa2_fd_get_frc() - Get the frame context in the frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the frame context field in the frame descriptor.
> + */
> +static inline u32 dpaa2_fd_get_frc(const struct dpaa2_fd *fd)
> +{
> +	return fd->simple.frc;
> +}
> +
> +/**
> + * dpaa2_fd_set_frc() - Set the frame context in the frame descriptor
> + * @fd: the given frame descriptor
> + * @frc: the frame context needs to be set in frame descriptor
> + */
> +static inline void dpaa2_fd_set_frc(struct dpaa2_fd *fd, u32 frc)
> +{
> +	fd->simple.frc = frc;
> +}
> +
> +/**
> + * dpaa2_fd_get_ctrl() - Get the control bits in the frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the control bits field in the frame descriptor.
> + */
> +static inline u32 dpaa2_fd_get_ctrl(const struct dpaa2_fd *fd)
> +{
> +	return fd->simple.ctrl;
> +}
> +
> +/**
> + * dpaa2_fd_set_ctrl() - Set the control bits in the frame descriptor
> + * @fd: the given frame descriptor
> + * @ctrl: the control bits to be set in the frame descriptor
> + */
> +static inline void dpaa2_fd_set_ctrl(struct dpaa2_fd *fd, u32 ctrl)
> +{
> +	fd->simple.ctrl = ctrl;
> +}
> +
> +/**
> + * dpaa2_fd_get_flc() - Get the flow context in the frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the flow context in the frame descriptor.
> + */
> +static inline dma_addr_t dpaa2_fd_get_flc(const struct dpaa2_fd *fd)
> +{
> +	return (dma_addr_t)fd->simple.flc;
> +}
> +
> +/**
> + * dpaa2_fd_set_flc() - Set the flow context field of frame descriptor
> + * @fd: the given frame descriptor
> + * @flc_addr: the flow context needs to be set in frame descriptor
> + */
> +static inline void dpaa2_fd_set_flc(struct dpaa2_fd *fd,  dma_addr_t flc_addr)
> +{
> +	fd->simple.flc = flc_addr;
> +}
> +
> +static inline bool dpaa2_fd_short_len(const struct dpaa2_fd *fd)
> +{
> +	return (fd->simple.format_offset >> FD_SHORT_LEN_FLAG_SHIFT)
> +		& FD_SHORT_LEN_FLAG_MASK;
> +}
> +
> +/**
> + * dpaa2_fd_get_len() - Get the length in the frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the length field in the frame descriptor.
> + */
> +static inline u32 dpaa2_fd_get_len(const struct dpaa2_fd *fd)
> +{
> +	if (dpaa2_fd_short_len(fd))
> +		return fd->simple.len & FD_SHORT_LEN_MASK;
> +
> +	return fd->simple.len;
> +}
> +
> +/**
> + * dpaa2_fd_set_len() - Set the length field of frame descriptor
> + * @fd: the given frame descriptor
> + * @len: the length needs to be set in frame descriptor
> + */
> +static inline void dpaa2_fd_set_len(struct dpaa2_fd *fd, u32 len)
> +{
> +	fd->simple.len = len;
> +}
> +
> +/**
> + * dpaa2_fd_get_offset() - Get the offset field in the frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the offset.
> + */
> +static inline uint16_t dpaa2_fd_get_offset(const struct dpaa2_fd *fd)
> +{
> +	return fd->simple.format_offset & FD_OFFSET_MASK;
> +}
> +
> +/**
> + * dpaa2_fd_set_offset() - Set the offset field of frame descriptor
> + * @fd: the given frame descriptor
> + * @offset: the offset needs to be set in frame descriptor
> + */
> +static inline void dpaa2_fd_set_offset(struct dpaa2_fd *fd, uint16_t offset)
> +{
> +	fd->simple.format_offset &= ~(FD_OFFSET_MASK);

Paranthesis not needed.

> +	fd->simple.format_offset |= offset;
> +}
> +
> +/**
> + * dpaa2_fd_get_format() - Get the format field in the frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the format.
> + */
> +static inline enum dpaa2_fd_format dpaa2_fd_get_format(
> +						const struct dpaa2_fd *fd)
> +{
> +	return (enum dpaa2_fd_format)((fd->simple.format_offset
> +				      >> FD_FORMAT_SHIFT) & FD_FORMAT_MASK);
> +}
> +
> +/**
> + * dpaa2_fd_set_format() - Set the format field of frame descriptor
> + * @fd: the given frame descriptor
> + * @format: the format needs to be set in frame descriptor
> + */
> +static inline void dpaa2_fd_set_format(struct dpaa2_fd *fd,
> +				       enum dpaa2_fd_format format)
> +{
> +	fd->simple.format_offset &= ~(FD_FORMAT_MASK << FD_FORMAT_SHIFT);
> +	fd->simple.format_offset |= format << FD_FORMAT_SHIFT;
> +}
> +
> +/**
> + * dpaa2_fd_get_bpid() - Get the bpid field in the frame descriptor
> + * @fd: the given frame descriptor
> + *
> + * Return the buffer pool id.
> + */
> +static inline uint16_t dpaa2_fd_get_bpid(const struct dpaa2_fd *fd)
> +{
> +	return fd->simple.bpid;
> +}
> +
> +/**
> + * dpaa2_fd_set_bpid() - Set the bpid field of frame descriptor
> + * @fd: the given frame descriptor
> + * @bpid: buffer pool id to be set
> + */
> +static inline void dpaa2_fd_set_bpid(struct dpaa2_fd *fd, uint16_t bpid)
> +{
> +	fd->simple.bpid = bpid;
> +}
> +
> +/**
> + * struct dpaa2_sg_entry - the scatter-gathering structure
> + * @addr: address of the sg entry
> + * @len: length in this sg entry
> + * @bpid: buffer pool id
> + * @format_offset: format and offset fields
> + */
> +struct dpaa2_sg_entry {
> +	__le64 addr;
> +	__le32 len;
> +	__le16 bpid;
> +	__le16 format_offset;
> +};
> +
> +enum dpaa2_sg_format {
> +	dpaa2_sg_single = 0,
> +	dpaa2_sg_frame_data,
> +	dpaa2_sg_sgt_ext
> +};
> +
> +/* Accessors for SG entry fields */
> +
> +/**
> + * dpaa2_sg_get_addr() - Get the address from SG entry
> + * @sg: the given scatter-gathering object
> + *
> + * Return the address.
> + */
> +static inline dma_addr_t dpaa2_sg_get_addr(const struct dpaa2_sg_entry *sg)
> +{
> +	return le64_to_cpu((dma_addr_t)sg->addr);
> +}
> +
> +/**
> + * dpaa2_sg_set_addr() - Set the address in SG entry
> + * @sg: the given scatter-gathering object
> + * @addr: the address to be set
> + */
> +static inline void dpaa2_sg_set_addr(struct dpaa2_sg_entry *sg, dma_addr_t addr)
> +{
> +	sg->addr = cpu_to_le64(addr);
> +}
> +
> +static inline bool dpaa2_sg_short_len(const struct dpaa2_sg_entry *sg)
> +{
> +	return (le16_to_cpu(sg->format_offset) >> SG_SHORT_LEN_FLAG_SHIFT)
> +		& SG_SHORT_LEN_FLAG_MASK;
> +}
> +
> +/**
> + * dpaa2_sg_get_len() - Get the length in SG entry
> + * @sg: the given scatter-gathering object
> + *
> + * Return the length.
> + */
> +static inline u32 dpaa2_sg_get_len(const struct dpaa2_sg_entry *sg)
> +{
> +	if (dpaa2_sg_short_len(sg))
> +		return le32_to_cpu(sg->len) & SG_SHORT_LEN_MASK;
> +
> +	return le32_to_cpu(sg->len);
> +}
> +
> +/**
> + * dpaa2_sg_set_len() - Set the length in SG entry
> + * @sg: the given scatter-gathering object
> + * @len: the length to be set
> + */
> +static inline void dpaa2_sg_set_len(struct dpaa2_sg_entry *sg, u32 len)
> +{
> +	sg->len = cpu_to_le32(len);
> +}
> +
> +/**
> + * dpaa2_sg_get_offset() - Get the offset in SG entry
> + * @sg: the given scatter-gathering object
> + *
> + * Return the offset.
> + */
> +static inline u16 dpaa2_sg_get_offset(const struct dpaa2_sg_entry *sg)
> +{
> +	return le16_to_cpu(sg->format_offset) & SG_OFFSET_MASK;
> +}
> +
> +/**
> + * dpaa2_sg_set_offset() - Set the offset in SG entry
> + * @sg: the given scatter-gathering object
> + * @offset: the offset to be set
> + */
> +static inline void dpaa2_sg_set_offset(struct dpaa2_sg_entry *sg,
> +				       u16 offset)
> +{
> +	sg->format_offset &= cpu_to_le16(~(SG_OFFSET_MASK));

Extra-paranthesis around SG_OFFSET_MASK not needed.

> +	sg->format_offset |= cpu_to_le16(offset);
> +}
> +
> +/**
> + * dpaa2_sg_get_format() - Get the SG format in SG entry
> + * @sg: the given scatter-gathering object
> + *
> + * Return the format.
> + */
> +static inline enum dpaa2_sg_format
> +	dpaa2_sg_get_format(const struct dpaa2_sg_entry *sg)
> +{
> +	return (enum dpaa2_sg_format)((le16_to_cpu(sg->format_offset)
> +				       >> SG_FORMAT_SHIFT) & SG_FORMAT_MASK);
> +}
> +
> +/**
> + * dpaa2_sg_set_format() - Set the SG format in SG entry
> + * @sg: the given scatter-gathering object
> + * @format: the format to be set
> + */
> +static inline void dpaa2_sg_set_format(struct dpaa2_sg_entry *sg,
> +				       enum dpaa2_sg_format format)
> +{
> +	sg->format_offset &= cpu_to_le16(~(SG_FORMAT_MASK << SG_FORMAT_SHIFT));
> +	sg->format_offset |= cpu_to_le16(format << SG_FORMAT_SHIFT);
> +}
> +
> +/**
> + * dpaa2_sg_get_bpid() - Get the buffer pool id in SG entry
> + * @sg: the given scatter-gathering object
> + *
> + * Return the bpid.
> + */
> +static inline u16 dpaa2_sg_get_bpid(const struct dpaa2_sg_entry *sg)
> +{
> +	return le16_to_cpu(sg->bpid) & SG_BPID_MASK;
> +}
> +
> +/**
> + * dpaa2_sg_set_bpid() - Set the buffer pool id in SG entry
> + * @sg: the given scatter-gathering object
> + * @bpid: the bpid to be set
> + */
> +static inline void dpaa2_sg_set_bpid(struct dpaa2_sg_entry *sg, u16 bpid)
> +{
> +	sg->bpid &= cpu_to_le16(~(SG_BPID_MASK));
> +	sg->bpid |= cpu_to_le16(bpid);
> +}
> +
> +/**
> + * dpaa2_sg_is_final() - Check final bit in SG entry
> + * @sg: the given scatter-gathering object
> + *
> + * Return bool.
> + */
> +static inline bool dpaa2_sg_is_final(const struct dpaa2_sg_entry *sg)
> +{
> +	return !!(le16_to_cpu(sg->format_offset) >> SG_FINAL_FLAG_SHIFT);

In other places in this file we don't use the '!!' to convert to bool. Maybe we should drop it here too.

> +}
> +
> +/**
> + * dpaa2_sg_set_final() - Set the final bit in SG entry
> + * @sg: the given scatter-gathering object
> + * @final: the final boolean to be set
> + */
> +static inline void dpaa2_sg_set_final(struct dpaa2_sg_entry *sg, bool final)
> +{
> +	sg->format_offset &= cpu_to_le16(~(SG_FINAL_FLAG_MASK
> +					 << SG_FINAL_FLAG_SHIFT));
> +	sg->format_offset |= cpu_to_le16(final << SG_FINAL_FLAG_SHIFT);
> +}
> +
> +#endif /* __FSL_DPAA2_FD_H */
> 

---
Best Regards, Laurentiu