--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2017-2020 Xilinx, Inc. All rights reserved.
+ * Copyright (C) 2022, Advanced Micro Devices, Inc.
+ */
+
+#ifndef __DMA_XDMA_REGS_H
+#define __DMA_XDMA_REGS_H
+
+/* The length of register space exposed to host */
+#define XDMA_REG_SPACE_LEN 65536
+
+/*
+ * maximum number of DMA channels for each direction:
+ * Host to Card (H2C) or Card to Host (C2H)
+ */
+#define XDMA_MAX_CHANNELS 4
+
+/*
+ * macros to define the number of descriptor blocks can be used in one
+ * DMA transfer request.
+ * the DMA engine uses a linked list of descriptor blocks that specify the
+ * source, destination, and length of the DMA transfers.
+ */
+#define XDMA_DESC_BLOCK_NUM BIT(7)
+#define XDMA_DESC_BLOCK_MASK (XDMA_DESC_BLOCK_NUM - 1)
+
+/* descriptor definitions */
+#define XDMA_DESC_ADJACENT 32
+#define XDMA_DESC_ADJACENT_MASK (XDMA_DESC_ADJACENT - 1)
+#define XDMA_DESC_ADJACENT_BITS GENMASK(13, 8)
+#define XDMA_DESC_MAGIC 0xad4bUL
+#define XDMA_DESC_MAGIC_BITS GENMASK(31, 16)
+#define XDMA_DESC_FLAGS_BITS GENMASK(7, 0)
+#define XDMA_DESC_STOPPED BIT(0)
+#define XDMA_DESC_COMPLETED BIT(1)
+#define XDMA_DESC_BLEN_BITS 28
+#define XDMA_DESC_BLEN_MAX (BIT(XDMA_DESC_BLEN_BITS) - PAGE_SIZE)
+
+/* macros to construct the descriptor control word */
+#define XDMA_DESC_CONTROL(adjacent, flag) \
+ (FIELD_PREP(XDMA_DESC_MAGIC_BITS, XDMA_DESC_MAGIC) | \
+ FIELD_PREP(XDMA_DESC_ADJACENT_BITS, (adjacent) - 1) | \
+ FIELD_PREP(XDMA_DESC_FLAGS_BITS, (flag)))
+#define XDMA_DESC_CONTROL_LAST \
+ XDMA_DESC_CONTROL(1, XDMA_DESC_STOPPED | XDMA_DESC_COMPLETED)
+
+/*
+ * Descriptor for a single contiguous memory block transfer.
+ *
+ * Multiple descriptors are linked by means of the next pointer. An additional
+ * extra adjacent number gives the amount of extra contiguous descriptors.
+ *
+ * The descriptors are in root complex memory, and the bytes in the 32-bit
+ * words must be in little-endian byte ordering.
+ */
+struct xdma_hw_desc {
+ __le32 control;
+ __le32 bytes;
+ __le64 src_addr;
+ __le64 dst_addr;
+ __le64 next_desc;
+};
+
+#define XDMA_DESC_SIZE sizeof(struct xdma_hw_desc)
+#define XDMA_DESC_BLOCK_SIZE (XDMA_DESC_SIZE * XDMA_DESC_ADJACENT)
+#define XDMA_DESC_BLOCK_ALIGN 4096
+
+/*
+ * Channel registers
+ */
+#define XDMA_CHAN_IDENTIFIER 0x0
+#define XDMA_CHAN_CONTROL 0x4
+#define XDMA_CHAN_CONTROL_W1S 0x8
+#define XDMA_CHAN_CONTROL_W1C 0xc
+#define XDMA_CHAN_STATUS 0x40
+#define XDMA_CHAN_COMPLETED_DESC 0x48
+#define XDMA_CHAN_ALIGNMENTS 0x4c
+#define XDMA_CHAN_INTR_ENABLE 0x90
+#define XDMA_CHAN_INTR_ENABLE_W1S 0x94
+#define XDMA_CHAN_INTR_ENABLE_W1C 0x9c
+
+#define XDMA_CHAN_STRIDE 0x100
+#define XDMA_CHAN_H2C_OFFSET 0x0
+#define XDMA_CHAN_C2H_OFFSET 0x1000
+#define XDMA_CHAN_H2C_TARGET 0x0
+#define XDMA_CHAN_C2H_TARGET 0x1
+
+/* macro to check if channel is available */
+#define XDMA_CHAN_MAGIC 0x1fc0
+#define XDMA_CHAN_CHECK_TARGET(id, target) \
+ (((u32)(id) >> 16) == XDMA_CHAN_MAGIC + (target))
+
+/* bits of the channel control register */
+#define CHAN_CTRL_RUN_STOP BIT(0)
+#define CHAN_CTRL_IE_DESC_STOPPED BIT(1)
+#define CHAN_CTRL_IE_DESC_COMPLETED BIT(2)
+#define CHAN_CTRL_IE_DESC_ALIGN_MISMATCH BIT(3)
+#define CHAN_CTRL_IE_MAGIC_STOPPED BIT(4)
+#define CHAN_CTRL_IE_IDLE_STOPPED BIT(6)
+#define CHAN_CTRL_IE_READ_ERROR GENMASK(13, 9)
+#define CHAN_CTRL_IE_DESC_ERROR GENMASK(23, 19)
+#define CHAN_CTRL_NON_INCR_ADDR BIT(25)
+#define CHAN_CTRL_POLL_MODE_WB BIT(26)
+
+#define CHAN_CTRL_START (CHAN_CTRL_RUN_STOP | \
+ CHAN_CTRL_IE_DESC_STOPPED | \
+ CHAN_CTRL_IE_DESC_COMPLETED | \
+ CHAN_CTRL_IE_DESC_ALIGN_MISMATCH | \
+ CHAN_CTRL_IE_MAGIC_STOPPED | \
+ CHAN_CTRL_IE_READ_ERROR | \
+ CHAN_CTRL_IE_DESC_ERROR)
+
+/* bits of the channel interrupt enable mask */
+#define CHAN_IM_DESC_ERROR BIT(19)
+#define CHAN_IM_READ_ERROR BIT(9)
+#define CHAN_IM_IDLE_STOPPED BIT(6)
+#define CHAN_IM_MAGIC_STOPPED BIT(4)
+#define CHAN_IM_DESC_COMPLETED BIT(2)
+#define CHAN_IM_DESC_STOPPED BIT(1)
+
+#define CHAN_IM_ALL (CHAN_IM_DESC_ERROR | CHAN_IM_READ_ERROR | \
+ CHAN_IM_IDLE_STOPPED | CHAN_IM_MAGIC_STOPPED | \
+ CHAN_IM_DESC_COMPLETED | CHAN_IM_DESC_STOPPED)
+
+/*
+ * Channel SGDMA registers
+ */
+#define XDMA_SGDMA_IDENTIFIER 0x4000
+#define XDMA_SGDMA_DESC_LO 0x4080
+#define XDMA_SGDMA_DESC_HI 0x4084
+#define XDMA_SGDMA_DESC_ADJ 0x4088
+#define XDMA_SGDMA_DESC_CREDIT 0x408c
+
+/* bits of the SG DMA control register */
+#define XDMA_CTRL_RUN_STOP BIT(0)
+#define XDMA_CTRL_IE_DESC_STOPPED BIT(1)
+#define XDMA_CTRL_IE_DESC_COMPLETED BIT(2)
+#define XDMA_CTRL_IE_DESC_ALIGN_MISMATCH BIT(3)
+#define XDMA_CTRL_IE_MAGIC_STOPPED BIT(4)
+#define XDMA_CTRL_IE_IDLE_STOPPED BIT(6)
+#define XDMA_CTRL_IE_READ_ERROR GENMASK(13, 9)
+#define XDMA_CTRL_IE_DESC_ERROR GENMASK(23, 19)
+#define XDMA_CTRL_NON_INCR_ADDR BIT(25)
+#define XDMA_CTRL_POLL_MODE_WB BIT(26)
+
+/*
+ * interrupt registers
+ */
+#define XDMA_IRQ_IDENTIFIER 0x2000
+#define XDMA_IRQ_USER_INT_EN 0x2004
+#define XDMA_IRQ_USER_INT_EN_W1S 0x2008
+#define XDMA_IRQ_USER_INT_EN_W1C 0x200c
+#define XDMA_IRQ_CHAN_INT_EN 0x2010
+#define XDMA_IRQ_CHAN_INT_EN_W1S 0x2014
+#define XDMA_IRQ_CHAN_INT_EN_W1C 0x2018
+#define XDMA_IRQ_USER_INT_REQ 0x2040
+#define XDMA_IRQ_CHAN_INT_REQ 0x2044
+#define XDMA_IRQ_USER_INT_PEND 0x2048
+#define XDMA_IRQ_CHAN_INT_PEND 0x204c
+#define XDMA_IRQ_USER_VEC_NUM 0x2080
+#define XDMA_IRQ_CHAN_VEC_NUM 0x20a0
+
+#define XDMA_IRQ_VEC_SHIFT 8
+
+#endif /* __DMA_XDMA_REGS_H */
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * DMA driver for Xilinx DMA/Bridge Subsystem
+ *
+ * Copyright (C) 2017-2020 Xilinx, Inc. All rights reserved.
+ * Copyright (C) 2022, Advanced Micro Devices, Inc.
+ */
+
+/*
+ * The DMA/Bridge Subsystem for PCI Express allows for the movement of data
+ * between Host memory and the DMA subsystem. It does this by operating on
+ * 'descriptors' that contain information about the source, destination and
+ * amount of data to transfer. These direct memory transfers can be both in
+ * the Host to Card (H2C) and Card to Host (C2H) transfers. The DMA can be
+ * configured to have a single AXI4 Master interface shared by all channels
+ * or one AXI4-Stream interface for each channel enabled. Memory transfers are
+ * specified on a per-channel basis in descriptor linked lists, which the DMA
+ * fetches from host memory and processes. Events such as descriptor completion
+ * and errors are signaled using interrupts. The core also provides up to 16
+ * user interrupt wires that generate interrupts to the host.
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/bitfield.h>
+#include <linux/dmapool.h>
+#include <linux/regmap.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/amd_xdma.h>
+#include <linux/dma-mapping.h>
+#include <linux/pci.h>
+#include "../virt-dma.h"
+#include "xdma-regs.h"
+
+/* mmio regmap config for all XDMA registers */
+static const struct regmap_config xdma_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = XDMA_REG_SPACE_LEN,
+};
+
+/**
+ * struct xdma_desc_block - Descriptor block
+ * @virt_addr: Virtual address of block start
+ * @dma_addr: DMA address of block start
+ */
+struct xdma_desc_block {
+ void *virt_addr;
+ dma_addr_t dma_addr;
+};
+
+/**
+ * struct xdma_chan - Driver specific DMA channel structure
+ * @vchan: Virtual channel
+ * @xdev_hdl: Pointer to DMA device structure
+ * @base: Offset of channel registers
+ * @desc_pool: Descriptor pool
+ * @busy: Busy flag of the channel
+ * @dir: Transferring direction of the channel
+ * @cfg: Transferring config of the channel
+ * @irq: IRQ assigned to the channel
+ */
+struct xdma_chan {
+ struct virt_dma_chan vchan;
+ void *xdev_hdl;
+ u32 base;
+ struct dma_pool *desc_pool;
+ bool busy;
+ enum dma_transfer_direction dir;
+ struct dma_slave_config cfg;
+ u32 irq;
+};
+
+/**
+ * struct xdma_desc - DMA desc structure
+ * @vdesc: Virtual DMA descriptor
+ * @chan: DMA channel pointer
+ * @dir: Transferring direction of the request
+ * @dev_addr: Physical address on DMA device side
+ * @desc_blocks: Hardware descriptor blocks
+ * @dblk_num: Number of hardware descriptor blocks
+ * @desc_num: Number of hardware descriptors
+ * @completed_desc_num: Completed hardware descriptors
+ */
+struct xdma_desc {
+ struct virt_dma_desc vdesc;
+ struct xdma_chan *chan;
+ enum dma_transfer_direction dir;
+ u64 dev_addr;
+ struct xdma_desc_block *desc_blocks;
+ u32 dblk_num;
+ u32 desc_num;
+ u32 completed_desc_num;
+};
+
+#define XDMA_DEV_STATUS_REG_DMA BIT(0)
+#define XDMA_DEV_STATUS_INIT_MSIX BIT(1)
+
+/**
+ * struct xdma_device - DMA device structure
+ * @pdev: Platform device pointer
+ * @dma_dev: DMA device structure
+ * @rmap: MMIO regmap for DMA registers
+ * @h2c_chans: Host to Card channels
+ * @c2h_chans: Card to Host channels
+ * @h2c_chan_num: Number of H2C channels
+ * @c2h_chan_num: Number of C2H channels
+ * @irq_start: Start IRQ assigned to device
+ * @irq_num: Number of IRQ assigned to device
+ * @status: Initialization status
+ */
+struct xdma_device {
+ struct platform_device *pdev;
+ struct dma_device dma_dev;
+ struct regmap *rmap;
+ struct xdma_chan *h2c_chans;
+ struct xdma_chan *c2h_chans;
+ u32 h2c_chan_num;
+ u32 c2h_chan_num;
+ u32 irq_start;
+ u32 irq_num;
+ u32 status;
+};
+
+#define xdma_err(xdev, fmt, args...) \
+ dev_err(&(xdev)->pdev->dev, fmt, ##args)
+#define XDMA_CHAN_NUM(_xd) ({ \
+ typeof(_xd) (xd) = (_xd); \
+ ((xd)->h2c_chan_num + (xd)->c2h_chan_num); })
+
+/* Get the last desc in a desc block */
+static inline void *xdma_blk_last_desc(struct xdma_desc_block *block)
+{
+ return block->virt_addr + (XDMA_DESC_ADJACENT - 1) * XDMA_DESC_SIZE;
+}
+
+/**
+ * xdma_link_desc_blocks - Link descriptor blocks for DMA transfer
+ * @sw_desc: Tx descriptor pointer
+ */
+static void xdma_link_desc_blocks(struct xdma_desc *sw_desc)
+{
+ struct xdma_desc_block *block;
+ u32 last_blk_desc, desc_control;
+ struct xdma_hw_desc *desc;
+ int i;
+
+ desc_control = XDMA_DESC_CONTROL(XDMA_DESC_ADJACENT, 0);
+ for (i = 1; i < sw_desc->dblk_num; i++) {
+ block = &sw_desc->desc_blocks[i - 1];
+ desc = xdma_blk_last_desc(block);
+
+ if (!(i & XDMA_DESC_BLOCK_MASK)) {
+ desc->control = cpu_to_le32(XDMA_DESC_CONTROL_LAST);
+ continue;
+ }
+ desc->control = cpu_to_le32(desc_control);
+ desc->next_desc = cpu_to_le64(block[1].dma_addr);
+ }
+
+ /* update the last block */
+ last_blk_desc = (sw_desc->desc_num - 1) & XDMA_DESC_ADJACENT_MASK;
+ if (((sw_desc->dblk_num - 1) & XDMA_DESC_BLOCK_MASK) > 0) {
+ block = &sw_desc->desc_blocks[sw_desc->dblk_num - 2];
+ desc = xdma_blk_last_desc(block);
+ desc_control = XDMA_DESC_CONTROL(last_blk_desc + 1, 0);
+ desc->control = cpu_to_le32(desc_control);
+ }
+
+ block = &sw_desc->desc_blocks[sw_desc->dblk_num - 1];
+ desc = block->virt_addr + last_blk_desc * XDMA_DESC_SIZE;
+ desc->control = cpu_to_le32(XDMA_DESC_CONTROL_LAST);
+}
+
+static inline struct xdma_chan *to_xdma_chan(struct dma_chan *chan)
+{
+ return container_of(chan, struct xdma_chan, vchan.chan);
+}
+
+static inline struct xdma_desc *to_xdma_desc(struct virt_dma_desc *vdesc)
+{
+ return container_of(vdesc, struct xdma_desc, vdesc);
+}
+
+/**
+ * xdma_channel_init - Initialize DMA channel registers
+ * @chan: DMA channel pointer
+ */
+static int xdma_channel_init(struct xdma_chan *chan)
+{
+ struct xdma_device *xdev = chan->xdev_hdl;
+ int ret;
+
+ ret = regmap_write(xdev->rmap, chan->base + XDMA_CHAN_CONTROL_W1C,
+ CHAN_CTRL_NON_INCR_ADDR);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(xdev->rmap, chan->base + XDMA_CHAN_INTR_ENABLE,
+ CHAN_IM_ALL);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+/**
+ * xdma_free_desc - Free descriptor
+ * @vdesc: Virtual DMA descriptor
+ */
+static void xdma_free_desc(struct virt_dma_desc *vdesc)
+{
+ struct xdma_desc *sw_desc;
+ int i;
+
+ sw_desc = to_xdma_desc(vdesc);
+ for (i = 0; i < sw_desc->dblk_num; i++) {
+ if (!sw_desc->desc_blocks[i].virt_addr)
+ break;
+ dma_pool_free(sw_desc->chan->desc_pool,
+ sw_desc->desc_blocks[i].virt_addr,
+ sw_desc->desc_blocks[i].dma_addr);
+ }
+ kfree(sw_desc->desc_blocks);
+ kfree(sw_desc);
+}
+
+/**
+ * xdma_alloc_desc - Allocate descriptor
+ * @chan: DMA channel pointer
+ * @desc_num: Number of hardware descriptors
+ */
+static struct xdma_desc *
+xdma_alloc_desc(struct xdma_chan *chan, u32 desc_num)
+{
+ struct xdma_desc *sw_desc;
+ struct xdma_hw_desc *desc;
+ dma_addr_t dma_addr;
+ u32 dblk_num;
+ void *addr;
+ int i, j;
+
+ sw_desc = kzalloc(sizeof(*sw_desc), GFP_NOWAIT);
+ if (!sw_desc)
+ return NULL;
+
+ sw_desc->chan = chan;
+ sw_desc->desc_num = desc_num;
+ dblk_num = DIV_ROUND_UP(desc_num, XDMA_DESC_ADJACENT);
+ sw_desc->desc_blocks = kcalloc(dblk_num, sizeof(*sw_desc->desc_blocks),
+ GFP_NOWAIT);
+ if (!sw_desc->desc_blocks)
+ goto failed;
+
+ sw_desc->dblk_num = dblk_num;
+ for (i = 0; i < sw_desc->dblk_num; i++) {
+ addr = dma_pool_alloc(chan->desc_pool, GFP_NOWAIT, &dma_addr);
+ if (!addr)
+ goto failed;
+
+ sw_desc->desc_blocks[i].virt_addr = addr;
+ sw_desc->desc_blocks[i].dma_addr = dma_addr;
+ for (j = 0, desc = addr; j < XDMA_DESC_ADJACENT; j++)
+ desc[j].control = cpu_to_le32(XDMA_DESC_CONTROL(1, 0));
+ }
+
+ xdma_link_desc_blocks(sw_desc);
+
+ return sw_desc;
+
+failed:
+ xdma_free_desc(&sw_desc->vdesc);
+ return NULL;
+}
+
+/**
+ * xdma_xfer_start - Start DMA transfer
+ * @xdma_chan: DMA channel pointer
+ */
+static int xdma_xfer_start(struct xdma_chan *xchan)
+{
+ struct virt_dma_desc *vd = vchan_next_desc(&xchan->vchan);
+ struct xdma_device *xdev = xchan->xdev_hdl;
+ struct xdma_desc_block *block;
+ u32 val, completed_blocks;
+ struct xdma_desc *desc;
+ int ret;
+
+ /*
+ * check if there is not any submitted descriptor or channel is busy.
+ * vchan lock should be held where this function is called.
+ */
+ if (!vd || xchan->busy)
+ return -EINVAL;
+
+ /* clear run stop bit to get ready for transfer */
+ ret = regmap_write(xdev->rmap, xchan->base + XDMA_CHAN_CONTROL_W1C,
+ CHAN_CTRL_RUN_STOP);
+ if (ret)
+ return ret;
+
+ desc = to_xdma_desc(vd);
+ if (desc->dir != xchan->dir) {
+ xdma_err(xdev, "incorrect request direction");
+ return -EINVAL;
+ }
+
+ /* set DMA engine to the first descriptor block */
+ completed_blocks = desc->completed_desc_num / XDMA_DESC_ADJACENT;
+ block = &desc->desc_blocks[completed_blocks];
+ val = lower_32_bits(block->dma_addr);
+ ret = regmap_write(xdev->rmap, xchan->base + XDMA_SGDMA_DESC_LO, val);
+ if (ret)
+ return ret;
+
+ val = upper_32_bits(block->dma_addr);
+ ret = regmap_write(xdev->rmap, xchan->base + XDMA_SGDMA_DESC_HI, val);
+ if (ret)
+ return ret;
+
+ if (completed_blocks + 1 == desc->dblk_num)
+ val = (desc->desc_num - 1) & XDMA_DESC_ADJACENT_MASK;
+ else
+ val = XDMA_DESC_ADJACENT - 1;
+ ret = regmap_write(xdev->rmap, xchan->base + XDMA_SGDMA_DESC_ADJ, val);
+ if (ret)
+ return ret;
+
+ /* kick off DMA transfer */
+ ret = regmap_write(xdev->rmap, xchan->base + XDMA_CHAN_CONTROL,
+ CHAN_CTRL_START);
+ if (ret)
+ return ret;
+
+ xchan->busy = true;
+ return 0;
+}
+
+/**
+ * xdma_alloc_channels - Detect and allocate DMA channels
+ * @xdev: DMA device pointer
+ * @dir: Channel direction
+ */
+static int xdma_alloc_channels(struct xdma_device *xdev,
+ enum dma_transfer_direction dir)
+{
+ struct xdma_platdata *pdata = dev_get_platdata(&xdev->pdev->dev);
+ struct xdma_chan **chans, *xchan;
+ u32 base, identifier, target;
+ u32 *chan_num;
+ int i, j, ret;
+
+ if (dir == DMA_MEM_TO_DEV) {
+ base = XDMA_CHAN_H2C_OFFSET;
+ target = XDMA_CHAN_H2C_TARGET;
+ chans = &xdev->h2c_chans;
+ chan_num = &xdev->h2c_chan_num;
+ } else if (dir == DMA_DEV_TO_MEM) {
+ base = XDMA_CHAN_C2H_OFFSET;
+ target = XDMA_CHAN_C2H_TARGET;
+ chans = &xdev->c2h_chans;
+ chan_num = &xdev->c2h_chan_num;
+ } else {
+ xdma_err(xdev, "invalid direction specified");
+ return -EINVAL;
+ }
+
+ /* detect number of available DMA channels */
+ for (i = 0, *chan_num = 0; i < pdata->max_dma_channels; i++) {
+ ret = regmap_read(xdev->rmap, base + i * XDMA_CHAN_STRIDE,
+ &identifier);
+ if (ret)
+ return ret;
+
+ /* check if it is available DMA channel */
+ if (XDMA_CHAN_CHECK_TARGET(identifier, target))
+ (*chan_num)++;
+ }
+
+ if (!*chan_num) {
+ xdma_err(xdev, "does not probe any channel");
+ return -EINVAL;
+ }
+
+ *chans = devm_kcalloc(&xdev->pdev->dev, *chan_num, sizeof(**chans),
+ GFP_KERNEL);
+ if (!*chans)
+ return -ENOMEM;
+
+ for (i = 0, j = 0; i < pdata->max_dma_channels; i++) {
+ ret = regmap_read(xdev->rmap, base + i * XDMA_CHAN_STRIDE,
+ &identifier);
+ if (ret)
+ return ret;
+
+ if (!XDMA_CHAN_CHECK_TARGET(identifier, target))
+ continue;
+
+ if (j == *chan_num) {
+ xdma_err(xdev, "invalid channel number");
+ return -EIO;
+ }
+
+ /* init channel structure and hardware */
+ xchan = &(*chans)[j];
+ xchan->xdev_hdl = xdev;
+ xchan->base = base + i * XDMA_CHAN_STRIDE;
+ xchan->dir = dir;
+
+ ret = xdma_channel_init(xchan);
+ if (ret)
+ return ret;
+ xchan->vchan.desc_free = xdma_free_desc;
+ vchan_init(&xchan->vchan, &xdev->dma_dev);
+
+ j++;
+ }
+
+ dev_info(&xdev->pdev->dev, "configured %d %s channels", j,
+ (dir == DMA_MEM_TO_DEV) ? "H2C" : "C2H");
+
+ return 0;
+}
+
+/**
+ * xdma_issue_pending - Issue pending transactions
+ * @chan: DMA channel pointer
+ */
+static void xdma_issue_pending(struct dma_chan *chan)
+{
+ struct xdma_chan *xdma_chan = to_xdma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&xdma_chan->vchan.lock, flags);
+ if (vchan_issue_pending(&xdma_chan->vchan))
+ xdma_xfer_start(xdma_chan);
+ spin_unlock_irqrestore(&xdma_chan->vchan.lock, flags);
+}
+
+/**
+ * xdma_prep_device_sg - prepare a descriptor for a DMA transaction
+ * @chan: DMA channel pointer
+ * @sgl: Transfer scatter gather list
+ * @sg_len: Length of scatter gather list
+ * @dir: Transfer direction
+ * @flags: transfer ack flags
+ * @context: APP words of the descriptor
+ */
+static struct dma_async_tx_descriptor *
+xdma_prep_device_sg(struct dma_chan *chan, struct scatterlist *sgl,
+ unsigned int sg_len, enum dma_transfer_direction dir,
+ unsigned long flags, void *context)
+{
+ struct xdma_chan *xdma_chan = to_xdma_chan(chan);
+ struct dma_async_tx_descriptor *tx_desc;
+ u32 desc_num = 0, i, len, rest;
+ struct xdma_desc_block *dblk;
+ struct xdma_hw_desc *desc;
+ struct xdma_desc *sw_desc;
+ u64 dev_addr, *src, *dst;
+ struct scatterlist *sg;
+ u64 addr;
+
+ for_each_sg(sgl, sg, sg_len, i)
+ desc_num += DIV_ROUND_UP(sg_dma_len(sg), XDMA_DESC_BLEN_MAX);
+
+ sw_desc = xdma_alloc_desc(xdma_chan, desc_num);
+ if (!sw_desc)
+ return NULL;
+ sw_desc->dir = dir;
+
+ if (dir == DMA_MEM_TO_DEV) {
+ dev_addr = xdma_chan->cfg.dst_addr;
+ src = &addr;
+ dst = &dev_addr;
+ } else {
+ dev_addr = xdma_chan->cfg.src_addr;
+ src = &dev_addr;
+ dst = &addr;
+ }
+
+ dblk = sw_desc->desc_blocks;
+ desc = dblk->virt_addr;
+ desc_num = 1;
+ for_each_sg(sgl, sg, sg_len, i) {
+ addr = sg_dma_address(sg);
+ rest = sg_dma_len(sg);
+
+ do {
+ len = min_t(u32, rest, XDMA_DESC_BLEN_MAX);
+ /* set hardware descriptor */
+ desc->bytes = cpu_to_le32(len);
+ desc->src_addr = cpu_to_le64(*src);
+ desc->dst_addr = cpu_to_le64(*dst);
+
+ if (!(desc_num & XDMA_DESC_ADJACENT_MASK)) {
+ dblk++;
+ desc = dblk->virt_addr;
+ } else {
+ desc++;
+ }
+
+ desc_num++;
+ dev_addr += len;
+ addr += len;
+ rest -= len;
+ } while (rest);
+ }
+
+ tx_desc = vchan_tx_prep(&xdma_chan->vchan, &sw_desc->vdesc, flags);
+ if (!tx_desc)
+ goto failed;
+
+ return tx_desc;
+
+failed:
+ xdma_free_desc(&sw_desc->vdesc);
+
+ return NULL;
+}
+
+/**
+ * xdma_device_config - Configure the DMA channel
+ * @chan: DMA channel
+ * @cfg: channel configuration
+ */
+static int xdma_device_config(struct dma_chan *chan,
+ struct dma_slave_config *cfg)
+{
+ struct xdma_chan *xdma_chan = to_xdma_chan(chan);
+
+ memcpy(&xdma_chan->cfg, cfg, sizeof(*cfg));
+
+ return 0;
+}
+
+/**
+ * xdma_free_chan_resources - Free channel resources
+ * @chan: DMA channel
+ */
+static void xdma_free_chan_resources(struct dma_chan *chan)
+{
+ struct xdma_chan *xdma_chan = to_xdma_chan(chan);
+
+ vchan_free_chan_resources(&xdma_chan->vchan);
+ dma_pool_destroy(xdma_chan->desc_pool);
+ xdma_chan->desc_pool = NULL;
+}
+
+/**
+ * xdma_alloc_chan_resources - Allocate channel resources
+ * @chan: DMA channel
+ */
+static int xdma_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct xdma_chan *xdma_chan = to_xdma_chan(chan);
+ struct xdma_device *xdev = xdma_chan->xdev_hdl;
+ struct device *dev = xdev->dma_dev.dev;
+
+ while (dev && !dev_is_pci(dev))
+ dev = dev->parent;
+ if (!dev) {
+ xdma_err(xdev, "unable to find pci device");
+ return -EINVAL;
+ }
+
+ xdma_chan->desc_pool = dma_pool_create(dma_chan_name(chan),
+ dev, XDMA_DESC_BLOCK_SIZE,
+ XDMA_DESC_BLOCK_ALIGN, 0);
+ if (!xdma_chan->desc_pool) {
+ xdma_err(xdev, "unable to allocate descriptor pool");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/**
+ * xdma_channel_isr - XDMA channel interrupt handler
+ * @irq: IRQ number
+ * @dev_id: Pointer to the DMA channel structure
+ */
+static irqreturn_t xdma_channel_isr(int irq, void *dev_id)
+{
+ struct xdma_chan *xchan = dev_id;
+ u32 complete_desc_num = 0;
+ struct xdma_device *xdev;
+ struct virt_dma_desc *vd;
+ struct xdma_desc *desc;
+ int ret;
+
+ spin_lock(&xchan->vchan.lock);
+
+ /* get submitted request */
+ vd = vchan_next_desc(&xchan->vchan);
+ if (!vd)
+ goto out;
+
+ xchan->busy = false;
+ desc = to_xdma_desc(vd);
+ xdev = xchan->xdev_hdl;
+
+ ret = regmap_read(xdev->rmap, xchan->base + XDMA_CHAN_COMPLETED_DESC,
+ &complete_desc_num);
+ if (ret)
+ goto out;
+
+ desc->completed_desc_num += complete_desc_num;
+ /*
+ * if all data blocks are transferred, remove and complete the request
+ */
+ if (desc->completed_desc_num == desc->desc_num) {
+ list_del(&vd->node);
+ vchan_cookie_complete(vd);
+ goto out;
+ }
+
+ if (desc->completed_desc_num > desc->desc_num ||
+ complete_desc_num != XDMA_DESC_BLOCK_NUM * XDMA_DESC_ADJACENT)
+ goto out;
+
+ /* transfer the rest of data */
+ xdma_xfer_start(xchan);
+
+out:
+ spin_unlock(&xchan->vchan.lock);
+ return IRQ_HANDLED;
+}
+
+/**
+ * xdma_irq_fini - Uninitialize IRQ
+ * @xdev: DMA device pointer
+ */
+static void xdma_irq_fini(struct xdma_device *xdev)
+{
+ int i;
+
+ /* disable interrupt */
+ regmap_write(xdev->rmap, XDMA_IRQ_CHAN_INT_EN_W1C, ~0);
+
+ /* free irq handler */
+ for (i = 0; i < xdev->h2c_chan_num; i++)
+ free_irq(xdev->h2c_chans[i].irq, &xdev->h2c_chans[i]);
+
+ for (i = 0; i < xdev->c2h_chan_num; i++)
+ free_irq(xdev->c2h_chans[i].irq, &xdev->c2h_chans[i]);
+}
+
+/**
+ * xdma_set_vector_reg - configure hardware IRQ registers
+ * @xdev: DMA device pointer
+ * @vec_tbl_start: Start of IRQ registers
+ * @irq_start: Start of IRQ
+ * @irq_num: Number of IRQ
+ */
+static int xdma_set_vector_reg(struct xdma_device *xdev, u32 vec_tbl_start,
+ u32 irq_start, u32 irq_num)
+{
+ u32 shift, i, val = 0;
+ int ret;
+
+ /* Each IRQ register is 32 bit and contains 4 IRQs */
+ while (irq_num > 0) {
+ for (i = 0; i < 4; i++) {
+ shift = XDMA_IRQ_VEC_SHIFT * i;
+ val |= irq_start << shift;
+ irq_start++;
+ irq_num--;
+ }
+
+ /* write IRQ register */
+ ret = regmap_write(xdev->rmap, vec_tbl_start, val);
+ if (ret)
+ return ret;
+ vec_tbl_start += sizeof(u32);
+ val = 0;
+ }
+
+ return 0;
+}
+
+/**
+ * xdma_irq_init - initialize IRQs
+ * @xdev: DMA device pointer
+ */
+static int xdma_irq_init(struct xdma_device *xdev)
+{
+ u32 irq = xdev->irq_start;
+ int i, j, ret;
+
+ /* return failure if there are not enough IRQs */
+ if (xdev->irq_num < XDMA_CHAN_NUM(xdev)) {
+ xdma_err(xdev, "not enough irq");
+ return -EINVAL;
+ }
+
+ /* setup H2C interrupt handler */
+ for (i = 0; i < xdev->h2c_chan_num; i++) {
+ ret = request_irq(irq, xdma_channel_isr, 0,
+ "xdma-h2c-channel", &xdev->h2c_chans[i]);
+ if (ret) {
+ xdma_err(xdev, "H2C channel%d request irq%d failed: %d",
+ i, irq, ret);
+ goto failed_init_h2c;
+ }
+ xdev->h2c_chans[i].irq = irq;
+ irq++;
+ }
+
+ /* setup C2H interrupt handler */
+ for (j = 0; j < xdev->c2h_chan_num; j++) {
+ ret = request_irq(irq, xdma_channel_isr, 0,
+ "xdma-c2h-channel", &xdev->c2h_chans[j]);
+ if (ret) {
+ xdma_err(xdev, "H2C channel%d request irq%d failed: %d",
+ j, irq, ret);
+ goto failed_init_c2h;
+ }
+ xdev->c2h_chans[j].irq = irq;
+ irq++;
+ }
+
+ /* config hardware IRQ registers */
+ ret = xdma_set_vector_reg(xdev, XDMA_IRQ_CHAN_VEC_NUM, 0,
+ XDMA_CHAN_NUM(xdev));
+ if (ret) {
+ xdma_err(xdev, "failed to set channel vectors: %d", ret);
+ goto failed_init_c2h;
+ }
+
+ /* enable interrupt */
+ ret = regmap_write(xdev->rmap, XDMA_IRQ_CHAN_INT_EN_W1S, ~0);
+ if (ret)
+ goto failed_init_c2h;
+
+ return 0;
+
+failed_init_c2h:
+ while (j--)
+ free_irq(xdev->c2h_chans[j].irq, &xdev->c2h_chans[j]);
+failed_init_h2c:
+ while (i--)
+ free_irq(xdev->h2c_chans[i].irq, &xdev->h2c_chans[i]);
+
+ return ret;
+}
+
+static bool xdma_filter_fn(struct dma_chan *chan, void *param)
+{
+ struct xdma_chan *xdma_chan = to_xdma_chan(chan);
+ struct xdma_chan_info *chan_info = param;
+
+ return chan_info->dir == xdma_chan->dir;
+}
+
+/**
+ * xdma_remove - Driver remove function
+ * @pdev: Pointer to the platform_device structure
+ */
+static int xdma_remove(struct platform_device *pdev)
+{
+ struct xdma_device *xdev = platform_get_drvdata(pdev);
+
+ if (xdev->status & XDMA_DEV_STATUS_INIT_MSIX)
+ xdma_irq_fini(xdev);
+
+ if (xdev->status & XDMA_DEV_STATUS_REG_DMA)
+ dma_async_device_unregister(&xdev->dma_dev);
+
+ return 0;
+}
+
+/**
+ * xdma_probe - Driver probe function
+ * @pdev: Pointer to the platform_device structure
+ */
+static int xdma_probe(struct platform_device *pdev)
+{
+ struct xdma_platdata *pdata = dev_get_platdata(&pdev->dev);
+ struct xdma_device *xdev;
+ void __iomem *reg_base;
+ struct resource *res;
+ int ret = -ENODEV;
+
+ if (pdata->max_dma_channels > XDMA_MAX_CHANNELS) {
+ dev_err(&pdev->dev, "invalid max dma channels %d",
+ pdata->max_dma_channels);
+ return -EINVAL;
+ }
+
+ xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
+ if (!xdev)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, xdev);
+ xdev->pdev = pdev;
+
+ res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!res) {
+ xdma_err(xdev, "failed to get irq resource");
+ goto failed;
+ }
+ xdev->irq_start = res->start;
+ xdev->irq_num = res->end - res->start + 1;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ xdma_err(xdev, "failed to get io resource");
+ goto failed;
+ }
+
+ reg_base = devm_ioremap_resource(&pdev->dev, res);
+ if (!reg_base) {
+ xdma_err(xdev, "ioremap failed");
+ goto failed;
+ }
+
+ xdev->rmap = devm_regmap_init_mmio(&pdev->dev, reg_base,
+ &xdma_regmap_config);
+ if (!xdev->rmap) {
+ xdma_err(xdev, "config regmap failed: %d", ret);
+ goto failed;
+ }
+ INIT_LIST_HEAD(&xdev->dma_dev.channels);
+
+ ret = xdma_alloc_channels(xdev, DMA_MEM_TO_DEV);
+ if (ret) {
+ xdma_err(xdev, "config H2C channels failed: %d", ret);
+ goto failed;
+ }
+
+ ret = xdma_alloc_channels(xdev, DMA_DEV_TO_MEM);
+ if (ret) {
+ xdma_err(xdev, "config C2H channels failed: %d", ret);
+ goto failed;
+ }
+
+ dma_cap_set(DMA_SLAVE, xdev->dma_dev.cap_mask);
+ dma_cap_set(DMA_PRIVATE, xdev->dma_dev.cap_mask);
+
+ xdev->dma_dev.dev = &pdev->dev;
+ xdev->dma_dev.device_free_chan_resources = xdma_free_chan_resources;
+ xdev->dma_dev.device_alloc_chan_resources = xdma_alloc_chan_resources;
+ xdev->dma_dev.device_tx_status = dma_cookie_status;
+ xdev->dma_dev.device_prep_slave_sg = xdma_prep_device_sg;
+ xdev->dma_dev.device_config = xdma_device_config;
+ xdev->dma_dev.device_issue_pending = xdma_issue_pending;
+ xdev->dma_dev.filter.map = pdata->device_map;
+ xdev->dma_dev.filter.mapcnt = pdata->device_map_cnt;
+ xdev->dma_dev.filter.fn = xdma_filter_fn;
+
+ ret = dma_async_device_register(&xdev->dma_dev);
+ if (ret) {
+ xdma_err(xdev, "failed to register Xilinx XDMA: %d", ret);
+ goto failed;
+ }
+ xdev->status |= XDMA_DEV_STATUS_REG_DMA;
+
+ ret = xdma_irq_init(xdev);
+ if (ret) {
+ xdma_err(xdev, "failed to init msix: %d", ret);
+ goto failed;
+ }
+ xdev->status |= XDMA_DEV_STATUS_INIT_MSIX;
+
+ return 0;
+
+failed:
+ xdma_remove(pdev);
+
+ return ret;
+}
+
+static const struct platform_device_id xdma_id_table[] = {
+ { "xdma", 0},
+ { },
+};
+
+static struct platform_driver xdma_driver = {
+ .driver = {
+ .name = "xdma",
+ },
+ .id_table = xdma_id_table,
+ .probe = xdma_probe,
+ .remove = xdma_remove,
+};
+
+module_platform_driver(xdma_driver);
+
+MODULE_DESCRIPTION("AMD XDMA driver");
+MODULE_AUTHOR("XRT Team <runtimeca39d@amd.com>");
+MODULE_LICENSE("GPL");
projects / platform / kernel / linux-rpi.git / commitdiff