From 73d5fc92a11cacb73a1aac0b5793c47e48c5b537 Mon Sep 17 00:00:00 2001 From: Nishad Saraf Date: Mon, 19 Aug 2024 14:19:48 -0700 Subject: dmaengine: amd: qdma: Add AMD QDMA driver Adds driver to enable PCIe board which uses AMD QDMA (the Queue-based Direct Memory Access) subsystem. For example, Xilinx Alveo V70 AI Accelerator devices. https://www.xilinx.com/applications/data-center/v70.html The QDMA subsystem is used in conjunction with the PCI Express IP block to provide high performance data transfer between host memory and the card's DMA subsystem. +-------+ +-------+ +-----------+ PCIe | | | | | | Tx/Rx | | | | AXI | | <=======> | PCIE | <===> | QDMA | <====>| User Logic| | | | | | | +-------+ +-------+ +-----------+ The primary mechanism to transfer data using the QDMA is for the QDMA engine to operate on instructions (descriptors) provided by the host operating system. Using the descriptors, the QDMA can move data in both the Host to Card (H2C) direction, or the Card to Host (C2H) direction. The QDMA provides a per-queue basis option whether DMA traffic goes to an AXI4 memory map (MM) interface or to an AXI4-Stream interface. The hardware detail is provided by https://docs.xilinx.com/r/en-US/pg302-qdma Implements dmaengine APIs to support MM DMA transfers. - probe the available DMA channels - use dma_slave_map for channel lookup - use virtual channel to manage dmaengine tx descriptors - implement device_prep_slave_sg callback to handle host scatter gather list Signed-off-by: Nishad Saraf Signed-off-by: Lizhi Hou Link: https://lore.kernel.org/r/20240819211948.688786-2-lizhi.hou@amd.com Signed-off-by: Vinod Koul --- include/linux/platform_data/amd_qdma.h | 36 ++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 include/linux/platform_data/amd_qdma.h (limited to 'include/linux/platform_data') diff --git a/include/linux/platform_data/amd_qdma.h b/include/linux/platform_data/amd_qdma.h new file mode 100644 index 000000000000..576d952f97ed --- /dev/null +++ b/include/linux/platform_data/amd_qdma.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2023-2024, Advanced Micro Devices, Inc. + */ + +#ifndef _PLATDATA_AMD_QDMA_H +#define _PLATDATA_AMD_QDMA_H + +#include + +/** + * struct qdma_queue_info - DMA queue information. This information is used to + * match queue when DMA channel is requested + * @dir: Channel transfer direction + */ +struct qdma_queue_info { + enum dma_transfer_direction dir; +}; + +#define QDMA_FILTER_PARAM(qinfo) ((void *)(qinfo)) + +struct dma_slave_map; + +/** + * struct qdma_platdata - Platform specific data for QDMA engine + * @max_mm_channels: Maximum number of MM DMA channels in each direction + * @device_map: DMA slave map + * @irq_index: The index of first IRQ + */ +struct qdma_platdata { + u32 max_mm_channels; + u32 irq_index; + struct dma_slave_map *device_map; +}; + +#endif /* _PLATDATA_AMD_QDMA_H */ -- cgit v1.2.3