[dpdk-dev] [RFC PATCH] dmadev: introduce DMA device library

[Wang, Haiyue]

> -----Original Message-----
> From: dev <dev-bounces at dpdk.org> On Behalf Of Chengwen Feng
> Sent: Tuesday, June 15, 2021 21:22
> To: thomas at monjalon.net; Yigit, Ferruh <ferruh.yigit at intel.com>
> Cc: dev at dpdk.org; nipun.gupta at nxp.com; hemant.agrawal at nxp.com; maxime.coquelin at redhat.com;
> honnappa.nagarahalli at arm.com; jerinj at marvell.com; david.marchand at redhat.com; Richardson, Bruce
> <bruce.richardson at intel.com>; jerinjacobk at gmail.com
> Subject: [dpdk-dev] [RFC PATCH] dmadev: introduce DMA device library
> 
> This patch introduces 'dmadevice' which is a generic type of DMA
> device.
> 
> The APIs of dmadev library exposes some generic operations which can
> enable configuration and I/O with the DMA devices.
> 
> Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
> ---
>  lib/dmadev/rte_dmadev.h     | 531 ++++++++++++++++++++++++++++++++++++++++++++
>  lib/dmadev/rte_dmadev_pmd.h | 384 ++++++++++++++++++++++++++++++++
>  2 files changed, 915 insertions(+)
>  create mode 100644 lib/dmadev/rte_dmadev.h
>  create mode 100644 lib/dmadev/rte_dmadev_pmd.h
> 
> diff --git a/lib/dmadev/rte_dmadev.h b/lib/dmadev/rte_dmadev.h
> new file mode 100644
> index 0000000..ca7c8a8
> --- /dev/null
> +++ b/lib/dmadev/rte_dmadev.h
> @@ -0,0 +1,531 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2021 HiSilicon Limited.
> + */
> +
> +#ifndef _RTE_DMADEV_H_
> +#define _RTE_DMADEV_H_
> +
> +/**
> + * @file rte_dmadev.h
> + *
> + * DMA (Direct Memory Access) device APIs.
> + *
> + * Defines RTE DMA Device APIs for DMA operations and its provisioning.
> + */
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +#include <rte_common.h>
> +#include <rte_memory.h>
> +#include <rte_errno.h>
> +#include <rte_compat.h>
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Get the total number of DMA devices that have been successfully
> + * initialised.
> + *
> + * @return
> + *   The total number of usable DMA devices.
> + */
> +__rte_experimental
> +uint16_t
> +rte_dmadev_count(void);
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Get the device identifier for the named DMA device.
> + *
> + * @param name
> + *   DMA device name to select the DMA device identifier.
> + *
> + * @return
> + *   Returns DMA device identifier on success.
> + *   - <0: Failure to find named DMA device.
> + */
> +__rte_experimental
> +int
> +rte_dmadev_get_dev_id(const char *name);
> +

Like 'struct rte_pci_device', 'struct rte_vdev_device', and new introduced
'struct rte_auxiliary_device', have the "rte_xxx_device" name style,
How about 'struct rte_dma_device' name ?

The API can be rte_dma_dev_get_dev_id ...

Just a suggestion.  ;-)


> +rte_dmadev_pmd_release(struct rte_dmadev *dev);


> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif /* _RTE_DMADEV_PMD_H_ */
> --
> 2.8.1