* [PATCH v3 3/5] dmaengine: vdma: Add Support for Xilinx AXI Direct Memory Access Engine
2016-04-06 16:15 [PATCH v3 0/5] dmaengine: vdma: AXI DMA's enhancments Kedareswara rao Appana
2016-04-06 16:15 ` [PATCH v3 1/5] Documentation: DT: vdma: Rename vdma-chan prefix to dma-chan Kedareswara rao Appana
[not found] ` <1459959335-24083-1-git-send-email-appanad-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org>
@ 2016-04-06 16:15 ` Kedareswara rao Appana
2016-04-06 16:15 ` [PATCH v3 4/5] Documentation: DT: vdma: update binding doc for AXI CDMA Kedareswara rao Appana
2016-04-06 16:15 ` [PATCH v3 5/5] dmaengine: vdma: Add Support for Xilinx AXI Central Direct Memory Access Engine Kedareswara rao Appana
4 siblings, 0 replies; 13+ messages in thread
From: Kedareswara rao Appana @ 2016-04-06 16:15 UTC (permalink / raw)
To: robh+dt, pawel.moll, mark.rutland, ijc+devicetree, galak,
michal.simek, soren.brinkmann, vinod.koul, dan.j.williams,
appanad, moritz.fischer, laurent.pinchart, luis, svemula, anirudh
Cc: devicetree, linux-arm-kernel, linux-kernel, dmaengine
This patch adds support for the AXI Direct Memory Access (AXI DMA)
core in the existing vdma driver, AXI DMA Core is a
soft Xilinx IP core that provides high-bandwidth
direct memory access between memory and AXI4-Stream
type target peripherals.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
---
Changes for v3:
---> None.
Changes for v2:
---> have differenet structures for h/w desc.
---> Added comments to the relevant sections as suggested by Laurent Pinchart.
---> Fixed trival code clean up/spacing issues as suggested by Laurent Pinchart
drivers/dma/xilinx/xilinx_vdma.c | 474 +++++++++++++++++++++++++++++++++++----
include/linux/dma/xilinx_dma.h | 12 +
2 files changed, 444 insertions(+), 42 deletions(-)
diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c
index 04fd8f5..3268415 100644
--- a/drivers/dma/xilinx/xilinx_vdma.c
+++ b/drivers/dma/xilinx/xilinx_vdma.c
@@ -16,6 +16,11 @@
* video device (S2MM). Initialization, status, interrupt and management
* registers are accessed through an AXI4-Lite slave interface.
*
+ * The AXI Direct Memory Access (AXI DMA) core is a soft Xilinx IP core that
+ * provides high-bandwidth one dimensional direct memory access between memory
+ * and AXI4-Stream target peripherals. It supports one receive and one
+ * transmit channel, both of them optional at synthesis time.
+ *
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
@@ -140,6 +145,19 @@
/* Delay loop counter to prevent hardware failure */
#define XILINX_DMA_LOOP_COUNT 1000000
+/* AXI DMA Specific Registers/Offsets */
+#define XILINX_DMA_REG_SRCDSTADDR 0x18
+#define XILINX_DMA_REG_BTT 0x28
+
+/* AXI DMA Specific Masks/Bit fields */
+#define XILINX_DMA_MAX_TRANS_LEN GENMASK(22, 0)
+#define XILINX_DMA_CR_COALESCE_MAX GENMASK(23, 16)
+#define XILINX_DMA_CR_COALESCE_SHIFT 16
+#define XILINX_DMA_BD_SOP BIT(27)
+#define XILINX_DMA_BD_EOP BIT(26)
+#define XILINX_DMA_COALESCE_MAX 255
+#define XILINX_DMA_NUM_APP_WORDS 5
+
/**
* struct xilinx_vdma_desc_hw - Hardware Descriptor
* @next_desc: Next Descriptor Pointer @0x00
@@ -162,6 +180,30 @@ struct xilinx_vdma_desc_hw {
} __aligned(64);
/**
+ * struct xilinx_axidma_desc_hw - Hardware Descriptor for AXI DMA
+ * @next_desc: Next Descriptor Pointer @0x00
+ * @pad1: Reserved @0x04
+ * @buf_addr: Buffer address @0x08
+ * @pad2: Reserved @0x0C
+ * @pad3: Reserved @0x10
+ * @pad4: Reserved @0x14
+ * @control: Control field @0x18
+ * @status: Status field @0x1C
+ * @app: APP Fields @0x20 - 0x30
+ */
+struct xilinx_axidma_desc_hw {
+ u32 next_desc;
+ u32 pad1;
+ u32 buf_addr;
+ u32 pad2;
+ u32 pad3;
+ u32 pad4;
+ u32 control;
+ u32 status;
+ u32 app[XILINX_DMA_NUM_APP_WORDS];
+} __aligned(64);
+
+/**
* struct xilinx_vdma_tx_segment - Descriptor segment
* @hw: Hardware descriptor
* @node: Node in the descriptor segments list
@@ -174,6 +216,18 @@ struct xilinx_vdma_tx_segment {
} __aligned(64);
/**
+ * struct xilinx_axidma_tx_segment - Descriptor segment
+ * @hw: Hardware descriptor
+ * @node: Node in the descriptor segments list
+ * @phys: Physical address of segment
+ */
+struct xilinx_axidma_tx_segment {
+ struct xilinx_axidma_desc_hw hw;
+ struct list_head node;
+ dma_addr_t phys;
+} __aligned(64);
+
+/**
* struct xilinx_dma_tx_descriptor - Per Transaction structure
* @async_tx: Async transaction descriptor
* @segments: TX segments list
@@ -210,6 +264,9 @@ struct xilinx_dma_tx_descriptor {
* @desc_pendingcount: Descriptor pending count
* @ext_addr: Indicates 64 bit addressing is supported by dma channel
* @desc_submitcount: Descriptor h/w submitted count
+ * @residue: Residue for AXI DMA
+ * @seg_v: Statically allocated segments base
+ * @start_transfer: Differentiate b/w DMA IP's transfer
*/
struct xilinx_dma_chan {
struct xilinx_dma_device *xdev;
@@ -235,6 +292,9 @@ struct xilinx_dma_chan {
u32 desc_pendingcount;
bool ext_addr;
u32 desc_submitcount;
+ u32 residue;
+ struct xilinx_axidma_tx_segment *seg_v;
+ void (*start_transfer)(struct xilinx_dma_chan *chan);
};
/**
@@ -246,6 +306,7 @@ struct xilinx_dma_chan {
* @has_sg: Specifies whether Scatter-Gather is present or not
* @flush_on_fsync: Flush on frame sync
* @ext_addr: Indicates 64 bit addressing is supported by dma device
+ * @dmatype: DMA ip type
*/
struct xilinx_dma_device {
void __iomem *regs;
@@ -255,6 +316,7 @@ struct xilinx_dma_device {
bool has_sg;
u32 flush_on_fsync;
bool ext_addr;
+ enum xdma_ip_type dmatype;
};
/* Macros */
@@ -354,6 +416,39 @@ xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
}
/**
+ * xilinx_axidma_alloc_tx_segment - Allocate transaction segment
+ * @chan: Driver specific DMA channel
+ *
+ * Return: The allocated segment on success and NULL on failure.
+ */
+static struct xilinx_axidma_tx_segment *
+xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
+{
+ struct xilinx_axidma_tx_segment *segment;
+ dma_addr_t phys;
+
+ segment = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &phys);
+ if (!segment)
+ return NULL;
+
+ memset(segment, 0, sizeof(*segment));
+ segment->phys = phys;
+
+ return segment;
+}
+
+/**
+ * xilinx_dma_free_tx_segment - Free transaction segment
+ * @chan: Driver specific DMA channel
+ * @segment: DMA transaction segment
+ */
+static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
+ struct xilinx_axidma_tx_segment *segment)
+{
+ dma_pool_free(chan->desc_pool, segment, segment->phys);
+}
+
+/**
* xilinx_vdma_free_tx_segment - Free transaction segment
* @chan: Driver specific DMA channel
* @segment: DMA transaction segment
@@ -394,13 +489,22 @@ xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
struct xilinx_dma_tx_descriptor *desc)
{
struct xilinx_vdma_tx_segment *segment, *next;
+ struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
if (!desc)
return;
- list_for_each_entry_safe(segment, next, &desc->segments, node) {
- list_del(&segment->node);
- xilinx_vdma_free_tx_segment(chan, segment);
+ if (chan->xdev->dmatype == XDMA_TYPE_VDMA) {
+ list_for_each_entry_safe(segment, next, &desc->segments, node) {
+ list_del(&segment->node);
+ xilinx_vdma_free_tx_segment(chan, segment);
+ }
+ } else {
+ list_for_each_entry_safe(axidma_segment, axidma_next,
+ &desc->segments, node) {
+ list_del(&axidma_segment->node);
+ xilinx_dma_free_tx_segment(chan, axidma_segment);
+ }
}
kfree(desc);
@@ -452,6 +556,8 @@ static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
dev_dbg(chan->dev, "Free all channel resources.\n");
xilinx_dma_free_descriptors(chan);
+ if (chan->xdev->dmatype == XDMA_TYPE_AXIDMA)
+ xilinx_dma_free_tx_segment(chan, chan->seg_v);
dma_pool_destroy(chan->desc_pool);
chan->desc_pool = NULL;
}
@@ -520,10 +626,20 @@ static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
* We need the descriptor to be aligned to 64bytes
* for meeting Xilinx VDMA specification requirement.
*/
- chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
- chan->dev,
- sizeof(struct xilinx_vdma_tx_segment),
- __alignof__(struct xilinx_vdma_tx_segment), 0);
+ if (chan->xdev->dmatype == XDMA_TYPE_AXIDMA) {
+ chan->desc_pool = dma_pool_create("xilinx_dma_desc_pool",
+ chan->dev,
+ sizeof(struct xilinx_axidma_tx_segment),
+ __alignof__(struct xilinx_axidma_tx_segment),
+ 0);
+ } else {
+ chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
+ chan->dev,
+ sizeof(struct xilinx_vdma_tx_segment),
+ __alignof__(struct xilinx_vdma_tx_segment),
+ 0);
+ }
+
if (!chan->desc_pool) {
dev_err(chan->dev,
"unable to allocate channel %d descriptor pool\n",
@@ -531,7 +647,27 @@ static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
return -ENOMEM;
}
+ if (chan->xdev->dmatype == XDMA_TYPE_AXIDMA)
+ /*
+ * For AXI DMA case after submitting a pending_list, keep
+ * an extra segment allocated so that the "next descriptor"
+ * pointer on the tail descriptor always points to a
+ * valid descriptor, even when paused after reaching taildesc.
+ * This way, it is possible to issue additional
+ * transfers without halting and restarting the channel.
+ */
+ chan->seg_v = xilinx_axidma_alloc_tx_segment(chan);
+
dma_cookie_init(dchan);
+
+ if (chan->xdev->dmatype == XDMA_TYPE_AXIDMA) {
+ /* For AXI DMA resetting once channel will reset the
+ * other channel as well so enable the interrupts here.
+ */
+ dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
+ XILINX_DMA_DMAXR_ALL_IRQ_MASK);
+ }
+
return 0;
}
@@ -547,7 +683,37 @@ static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
- return dma_cookie_status(dchan, cookie, txstate);
+ struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
+ struct xilinx_dma_tx_descriptor *desc;
+ struct xilinx_axidma_tx_segment *segment;
+ struct xilinx_axidma_desc_hw *hw;
+ enum dma_status ret;
+ unsigned long flags;
+ u32 residue = 0;
+
+ ret = dma_cookie_status(dchan, cookie, txstate);
+ if (ret == DMA_COMPLETE || !txstate)
+ return ret;
+
+ if (chan->xdev->dmatype == XDMA_TYPE_AXIDMA) {
+ spin_lock_irqsave(&chan->lock, flags);
+
+ desc = list_last_entry(&chan->active_list,
+ struct xilinx_dma_tx_descriptor, node);
+ if (chan->has_sg) {
+ list_for_each_entry(segment, &desc->segments, node) {
+ hw = &segment->hw;
+ residue += (hw->control - hw->status) &
+ XILINX_DMA_MAX_TRANS_LEN;
+ }
+ }
+ spin_unlock_irqrestore(&chan->lock, flags);
+
+ chan->residue = residue;
+ dma_set_residue(txstate, chan->residue);
+ }
+
+ return ret;
}
/**
@@ -755,6 +921,91 @@ static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
}
/**
+ * xilinx_dma_start_transfer - Starts DMA transfer
+ * @chan: Driver specific channel struct pointer
+ */
+static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
+{
+ struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
+ struct xilinx_axidma_tx_segment *tail_segment, *old_head, *new_head;
+ u32 reg;
+
+ if (chan->err)
+ return;
+
+ if (list_empty(&chan->pending_list))
+ return;
+
+ /* If it is SG mode and hardware is busy, cannot submit */
+ if (chan->has_sg && xilinx_dma_is_running(chan) &&
+ !xilinx_dma_is_idle(chan)) {
+ dev_dbg(chan->dev, "DMA controller still busy\n");
+ return;
+ }
+
+ head_desc = list_first_entry(&chan->pending_list,
+ struct xilinx_dma_tx_descriptor, node);
+ tail_desc = list_last_entry(&chan->pending_list,
+ struct xilinx_dma_tx_descriptor, node);
+ tail_segment = list_last_entry(&tail_desc->segments,
+ struct xilinx_axidma_tx_segment, node);
+
+ old_head = list_first_entry(&head_desc->segments,
+ struct xilinx_axidma_tx_segment, node);
+ new_head = chan->seg_v;
+ /* Copy Buffer Descriptor fields. */
+ new_head->hw = old_head->hw;
+
+ /* Swap and save new reserve */
+ list_replace_init(&old_head->node, &new_head->node);
+ chan->seg_v = old_head;
+
+ tail_segment->hw.next_desc = chan->seg_v->phys;
+ head_desc->async_tx.phys = new_head->phys;
+
+ reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
+
+ if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
+ reg &= ~XILINX_DMA_CR_COALESCE_MAX;
+ reg |= chan->desc_pendingcount <<
+ XILINX_DMA_CR_COALESCE_SHIFT;
+ dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
+ }
+
+ if (chan->has_sg)
+ dma_ctrl_write(chan, XILINX_DMA_REG_CURDESC,
+ head_desc->async_tx.phys);
+
+ xilinx_dma_start(chan);
+
+ if (chan->err)
+ return;
+
+ /* Start the transfer */
+ if (chan->has_sg) {
+ dma_ctrl_write(chan, XILINX_DMA_REG_TAILDESC,
+ tail_segment->phys);
+ } else {
+ struct xilinx_axidma_tx_segment *segment;
+ struct xilinx_axidma_desc_hw *hw;
+
+ segment = list_first_entry(&head_desc->segments,
+ struct xilinx_axidma_tx_segment,
+ node);
+ hw = &segment->hw;
+
+ dma_ctrl_write(chan, XILINX_DMA_REG_SRCDSTADDR, hw->buf_addr);
+
+ /* Start the transfer */
+ dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
+ hw->control & XILINX_DMA_MAX_TRANS_LEN);
+ }
+
+ list_splice_tail_init(&chan->pending_list, &chan->active_list);
+ chan->desc_pendingcount = 0;
+}
+
+/**
* xilinx_dma_issue_pending - Issue pending transactions
* @dchan: DMA channel
*/
@@ -764,7 +1015,7 @@ static void xilinx_dma_issue_pending(struct dma_chan *dchan)
unsigned long flags;
spin_lock_irqsave(&chan->lock, flags);
- xilinx_vdma_start_transfer(chan);
+ chan->start_transfer(chan);
spin_unlock_irqrestore(&chan->lock, flags);
}
@@ -896,7 +1147,7 @@ static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) {
spin_lock(&chan->lock);
xilinx_dma_complete_descriptor(chan);
- xilinx_vdma_start_transfer(chan);
+ chan->start_transfer(chan);
spin_unlock(&chan->lock);
}
@@ -914,6 +1165,7 @@ static void append_desc_queue(struct xilinx_dma_chan *chan,
{
struct xilinx_vdma_tx_segment *tail_segment;
struct xilinx_dma_tx_descriptor *tail_desc;
+ struct xilinx_axidma_tx_segment *axidma_tail_segment;
if (list_empty(&chan->pending_list))
goto append;
@@ -924,9 +1176,17 @@ static void append_desc_queue(struct xilinx_dma_chan *chan,
*/
tail_desc = list_last_entry(&chan->pending_list,
struct xilinx_dma_tx_descriptor, node);
- tail_segment = list_last_entry(&tail_desc->segments,
- struct xilinx_vdma_tx_segment, node);
- tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
+ if (chan->xdev->dmatype == XDMA_TYPE_VDMA) {
+ tail_segment = list_last_entry(&tail_desc->segments,
+ struct xilinx_vdma_tx_segment,
+ node);
+ tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
+ } else {
+ axidma_tail_segment = list_last_entry(&tail_desc->segments,
+ struct xilinx_axidma_tx_segment,
+ node);
+ axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
+ }
/*
* Add the software descriptor and all children to the list
@@ -936,7 +1196,7 @@ append:
list_add_tail(&desc->node, &chan->pending_list);
chan->desc_pendingcount++;
- if (chan->has_sg &&
+ if (chan->has_sg && (chan->xdev->dmatype == XDMA_TYPE_VDMA) &&
unlikely(chan->desc_pendingcount > chan->num_frms)) {
dev_dbg(chan->dev, "desc pendingcount is too high\n");
chan->desc_pendingcount = chan->num_frms;
@@ -1064,6 +1324,109 @@ error:
}
/**
+ * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
+ * @dchan: DMA channel
+ * @sgl: scatterlist to transfer to/from
+ * @sg_len: number of entries in @scatterlist
+ * @direction: DMA direction
+ * @flags: transfer ack flags
+ * @context: APP words of the descriptor
+ *
+ * Return: Async transaction descriptor on success and NULL on failure
+ */
+static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
+ struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
+ enum dma_transfer_direction direction, unsigned long flags,
+ void *context)
+{
+ struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
+ struct xilinx_dma_tx_descriptor *desc;
+ struct xilinx_axidma_tx_segment *segment = NULL, *prev = NULL;
+ u32 *app_w = (u32 *)context;
+ struct scatterlist *sg;
+ size_t copy;
+ size_t sg_used;
+ unsigned int i;
+
+ if (!is_slave_direction(direction))
+ return NULL;
+
+ /* Allocate a transaction descriptor. */
+ desc = xilinx_dma_alloc_tx_descriptor(chan);
+ if (!desc)
+ return NULL;
+
+ dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
+ desc->async_tx.tx_submit = xilinx_dma_tx_submit;
+
+ /* Build transactions using information in the scatter gather list */
+ for_each_sg(sgl, sg, sg_len, i) {
+ sg_used = 0;
+
+ /* Loop until the entire scatterlist entry is used */
+ while (sg_used < sg_dma_len(sg)) {
+ struct xilinx_axidma_desc_hw *hw;
+
+ /* Get a free segment */
+ segment = xilinx_axidma_alloc_tx_segment(chan);
+ if (!segment)
+ goto error;
+
+ /*
+ * Calculate the maximum number of bytes to transfer,
+ * making sure it is less than the hw limit
+ */
+ copy = min_t(size_t, sg_dma_len(sg) - sg_used,
+ XILINX_DMA_MAX_TRANS_LEN);
+ hw = &segment->hw;
+
+ /* Fill in the descriptor */
+ hw->buf_addr = sg_dma_address(sg) + sg_used;
+
+ hw->control = copy;
+
+ if (chan->direction == DMA_MEM_TO_DEV) {
+ if (app_w)
+ memcpy(hw->app, app_w, sizeof(u32) *
+ XILINX_DMA_NUM_APP_WORDS);
+ }
+
+ if (prev)
+ prev->hw.next_desc = segment->phys;
+
+ prev = segment;
+ sg_used += copy;
+
+ /*
+ * Insert the segment into the descriptor segments
+ * list.
+ */
+ list_add_tail(&segment->node, &desc->segments);
+ }
+ }
+
+ segment = list_first_entry(&desc->segments,
+ struct xilinx_axidma_tx_segment, node);
+ desc->async_tx.phys = segment->phys;
+ prev->hw.next_desc = segment->phys;
+
+ /* For the last DMA_MEM_TO_DEV transfer, set EOP */
+ if (chan->direction == DMA_MEM_TO_DEV) {
+ segment->hw.control |= XILINX_DMA_BD_SOP;
+ segment = list_last_entry(&desc->segments,
+ struct xilinx_axidma_tx_segment,
+ node);
+ segment->hw.control |= XILINX_DMA_BD_EOP;
+ }
+
+ return &desc->async_tx;
+
+error:
+ xilinx_dma_free_tx_descriptor(chan, desc);
+ return NULL;
+}
+
+/**
* xilinx_dma_terminate_all - Halt the channel and free descriptors
* @chan: Driver specific DMA Channel pointer
*/
@@ -1225,22 +1588,26 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
chan->id = 0;
chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
- chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
+ if (xdev->dmatype == XDMA_TYPE_VDMA) {
+ chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
- if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
- xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
- chan->flush_on_fsync = true;
+ if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
+ xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
+ chan->flush_on_fsync = true;
+ }
} else if (of_device_is_compatible(node,
"xlnx,axi-dma-s2mm-channel")) {
chan->direction = DMA_DEV_TO_MEM;
chan->id = 1;
chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
- chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
+ if (xdev->dmatype == XDMA_TYPE_VDMA) {
+ chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
- if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
- xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
- chan->flush_on_fsync = true;
+ if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
+ xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
+ chan->flush_on_fsync = true;
+ }
} else {
dev_err(xdev->dev, "Invalid channel compatible node\n");
return -EINVAL;
@@ -1255,6 +1622,11 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
return err;
}
+ if (xdev->dmatype == XDMA_TYPE_AXIDMA)
+ chan->start_transfer = xilinx_dma_start_transfer;
+ else
+ chan->start_transfer = xilinx_vdma_start_transfer;
+
/* Initialize the tasklet */
tasklet_init(&chan->tasklet, xilinx_dma_do_tasklet,
(unsigned long)chan);
@@ -1297,6 +1669,15 @@ static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
return dma_get_slave_channel(&xdev->chan[chan_id]->common);
}
+static const struct of_device_id xilinx_dma_of_ids[] = {
+ { .compatible = "xlnx,axi-dma-1.00.a",
+ .data = (void *)XDMA_TYPE_AXIDMA },
+ { .compatible = "xlnx,axi-vdma-1.00.a",
+ .data = (void *)XDMA_TYPE_VDMA },
+ {}
+};
+MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
+
/**
* xilinx_dma_probe - Driver probe function
* @pdev: Pointer to the platform_device structure
@@ -1318,6 +1699,7 @@ static int xilinx_dma_probe(struct platform_device *pdev)
return -ENOMEM;
xdev->dev = &pdev->dev;
+ xdev->dmatype = (enum xdma_ip_type)of_device_get_match_data(&pdev->dev);
/* Request and map I/O memory */
io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1328,16 +1710,21 @@ static int xilinx_dma_probe(struct platform_device *pdev)
/* Retrieve the DMA engine properties from the device tree */
xdev->has_sg = of_property_read_bool(node, "xlnx,include-sg");
- err = of_property_read_u32(node, "xlnx,num-fstores", &num_frames);
- if (err < 0) {
- dev_err(xdev->dev, "missing xlnx,num-fstores property\n");
- return err;
- }
+ if (xdev->dmatype == XDMA_TYPE_VDMA) {
+ err = of_property_read_u32(node, "xlnx,num-fstores",
+ &num_frames);
+ if (err < 0) {
+ dev_err(xdev->dev,
+ "missing xlnx,num-fstores property\n");
+ return err;
+ }
- err = of_property_read_u32(node, "xlnx,flush-fsync",
- &xdev->flush_on_fsync);
- if (err < 0)
- dev_warn(xdev->dev, "missing xlnx,flush-fsync property\n");
+ err = of_property_read_u32(node, "xlnx,flush-fsync",
+ &xdev->flush_on_fsync);
+ if (err < 0)
+ dev_warn(xdev->dev,
+ "missing xlnx,flush-fsync property\n");
+ }
err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
if (err < 0)
@@ -1362,11 +1749,18 @@ static int xilinx_dma_probe(struct platform_device *pdev)
xilinx_dma_alloc_chan_resources;
xdev->common.device_free_chan_resources =
xilinx_dma_free_chan_resources;
- xdev->common.device_prep_interleaved_dma =
- xilinx_vdma_dma_prep_interleaved;
xdev->common.device_terminate_all = xilinx_dma_terminate_all;
xdev->common.device_tx_status = xilinx_dma_tx_status;
xdev->common.device_issue_pending = xilinx_dma_issue_pending;
+ if (xdev->dmatype == XDMA_TYPE_AXIDMA) {
+ xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
+ /* Residue calculation is supported by only AXI DMA */
+ xdev->common.residue_granularity =
+ DMA_RESIDUE_GRANULARITY_SEGMENT;
+ } else {
+ xdev->common.device_prep_interleaved_dma =
+ xilinx_vdma_dma_prep_interleaved;
+ }
platform_set_drvdata(pdev, xdev);
@@ -1377,9 +1771,11 @@ static int xilinx_dma_probe(struct platform_device *pdev)
goto error;
}
- for (i = 0; i < XILINX_DMA_MAX_CHANS_PER_DEVICE; i++)
- if (xdev->chan[i])
- xdev->chan[i]->num_frms = num_frames;
+ if (xdev->dmatype == XDMA_TYPE_VDMA) {
+ for (i = 0; i < XILINX_DMA_MAX_CHANS_PER_DEVICE; i++)
+ if (xdev->chan[i])
+ xdev->chan[i]->num_frms = num_frames;
+ }
/* Register the DMA engine with the core */
dma_async_device_register(&xdev->common);
@@ -1426,12 +1822,6 @@ static int xilinx_dma_remove(struct platform_device *pdev)
return 0;
}
-static const struct of_device_id xilinx_dma_of_ids[] = {
- { .compatible = "xlnx,axi-vdma-1.00.a",},
- {}
-};
-MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
-
static struct platform_driver xilinx_vdma_driver = {
.driver = {
.name = "xilinx-vdma",
diff --git a/include/linux/dma/xilinx_dma.h b/include/linux/dma/xilinx_dma.h
index 34b98f2..e25872b 100644
--- a/include/linux/dma/xilinx_dma.h
+++ b/include/linux/dma/xilinx_dma.h
@@ -41,6 +41,18 @@ struct xilinx_vdma_config {
int ext_fsync;
};
+/**
+ * enum xdma_ip_type: DMA IP type.
+ *
+ * XDMA_TYPE_DMA: Axi dma ip.
+ * XDMA_TYPE_VDMA: Axi vdma ip.
+ *
+ */
+enum xdma_ip_type {
+ XDMA_TYPE_AXIDMA = 0,
+ XDMA_TYPE_VDMA,
+};
+
int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
struct xilinx_vdma_config *cfg);
--
2.1.2
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH v3 5/5] dmaengine: vdma: Add Support for Xilinx AXI Central Direct Memory Access Engine
2016-04-06 16:15 [PATCH v3 0/5] dmaengine: vdma: AXI DMA's enhancments Kedareswara rao Appana
` (3 preceding siblings ...)
2016-04-06 16:15 ` [PATCH v3 4/5] Documentation: DT: vdma: update binding doc for AXI CDMA Kedareswara rao Appana
@ 2016-04-06 16:15 ` Kedareswara rao Appana
4 siblings, 0 replies; 13+ messages in thread
From: Kedareswara rao Appana @ 2016-04-06 16:15 UTC (permalink / raw)
To: robh+dt, pawel.moll, mark.rutland, ijc+devicetree, galak,
michal.simek, soren.brinkmann, vinod.koul, dan.j.williams,
appanad, moritz.fischer, laurent.pinchart, luis, svemula, anirudh
Cc: devicetree, linux-arm-kernel, linux-kernel, dmaengine
This patch adds support for the AXI Central Direct Memory Access
(AXI CDMA) core to the existing vdma driver, AXI CDMA is a
soft Xilinx IP core that provides high-bandwidth
Direct Memory Access(DMA) between a memory-mapped
source address and a memory-mapped destination address.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
---
Changes for v3:
---> None.
Changes for v2:
---> have differenet structures for h/w desc.
---> Added comments to the relevant sections as suggested by Laurent Pinchart.
---> Fixed trival code clean up/spacing issues as suggested by Laurent Pinchart.
drivers/dma/xilinx/xilinx_vdma.c | 236 ++++++++++++++++++++++++++++++++++++++-
include/linux/dma/xilinx_dma.h | 2 +
2 files changed, 236 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c
index 3268415..e5771a0 100644
--- a/drivers/dma/xilinx/xilinx_vdma.c
+++ b/drivers/dma/xilinx/xilinx_vdma.c
@@ -21,6 +21,10 @@
* and AXI4-Stream target peripherals. It supports one receive and one
* transmit channel, both of them optional at synthesis time.
*
+ * The AXI CDMA, is a soft IP, which provides high-bandwidth Direct Memory
+ * Access (DMA) between a memory-mapped source address and a memory-mapped
+ * destination address.
+ *
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
@@ -158,6 +162,13 @@
#define XILINX_DMA_COALESCE_MAX 255
#define XILINX_DMA_NUM_APP_WORDS 5
+/* AXI CDMA Specific Registers/Offsets */
+#define XILINX_CDMA_REG_SRCADDR 0x18
+#define XILINX_CDMA_REG_DSTADDR 0x20
+
+/* AXI CDMA Specific Masks */
+#define XILINX_CDMA_CR_SGMODE BIT(3)
+
/**
* struct xilinx_vdma_desc_hw - Hardware Descriptor
* @next_desc: Next Descriptor Pointer @0x00
@@ -204,6 +215,28 @@ struct xilinx_axidma_desc_hw {
} __aligned(64);
/**
+ * struct xilinx_cdma_desc_hw - Hardware Descriptor
+ * @next_desc: Next Descriptor Pointer @0x00
+ * @pad1: Reserved @0x04
+ * @src_addr: Source address @0x08
+ * @pad2: Reserved @0x0C
+ * @dest_addr: Destination address @0x10
+ * @pad3: Reserved @0x14
+ * @control: Control field @0x18
+ * @status: Status field @0x1C
+ */
+struct xilinx_cdma_desc_hw {
+ u32 next_desc;
+ u32 pad1;
+ u32 src_addr;
+ u32 pad2;
+ u32 dest_addr;
+ u32 pad3;
+ u32 control;
+ u32 status;
+} __aligned(64);
+
+/**
* struct xilinx_vdma_tx_segment - Descriptor segment
* @hw: Hardware descriptor
* @node: Node in the descriptor segments list
@@ -228,6 +261,18 @@ struct xilinx_axidma_tx_segment {
} __aligned(64);
/**
+ * struct xilinx_cdma_tx_segment - Descriptor segment
+ * @hw: Hardware descriptor
+ * @node: Node in the descriptor segments list
+ * @phys: Physical address of segment
+ */
+struct xilinx_cdma_tx_segment {
+ struct xilinx_cdma_desc_hw hw;
+ struct list_head node;
+ dma_addr_t phys;
+} __aligned(64);
+
+/**
* struct xilinx_dma_tx_descriptor - Per Transaction structure
* @async_tx: Async transaction descriptor
* @segments: TX segments list
@@ -416,6 +461,28 @@ xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
}
/**
+ * xilinx_cdma_alloc_tx_segment - Allocate transaction segment
+ * @chan: Driver specific DMA channel
+ *
+ * Return: The allocated segment on success and NULL on failure.
+ */
+static struct xilinx_cdma_tx_segment *
+xilinx_cdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
+{
+ struct xilinx_cdma_tx_segment *segment;
+ dma_addr_t phys;
+
+ segment = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &phys);
+ if (!segment)
+ return NULL;
+
+ memset(segment, 0, sizeof(*segment));
+ segment->phys = phys;
+
+ return segment;
+}
+
+/**
* xilinx_axidma_alloc_tx_segment - Allocate transaction segment
* @chan: Driver specific DMA channel
*
@@ -449,6 +516,17 @@ static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
}
/**
+ * xilinx_cdma_free_tx_segment - Free transaction segment
+ * @chan: Driver specific DMA channel
+ * @segment: DMA transaction segment
+ */
+static void xilinx_cdma_free_tx_segment(struct xilinx_dma_chan *chan,
+ struct xilinx_cdma_tx_segment *segment)
+{
+ dma_pool_free(chan->desc_pool, segment, segment->phys);
+}
+
+/**
* xilinx_vdma_free_tx_segment - Free transaction segment
* @chan: Driver specific DMA channel
* @segment: DMA transaction segment
@@ -489,6 +567,7 @@ xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
struct xilinx_dma_tx_descriptor *desc)
{
struct xilinx_vdma_tx_segment *segment, *next;
+ struct xilinx_cdma_tx_segment *cdma_segment, *cdma_next;
struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
if (!desc)
@@ -499,6 +578,12 @@ xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
list_del(&segment->node);
xilinx_vdma_free_tx_segment(chan, segment);
}
+ } else if (chan->xdev->dmatype == XDMA_TYPE_CDMA) {
+ list_for_each_entry_safe(cdma_segment, cdma_next,
+ &desc->segments, node) {
+ list_del(&cdma_segment->node);
+ xilinx_cdma_free_tx_segment(chan, cdma_segment);
+ }
} else {
list_for_each_entry_safe(axidma_segment, axidma_next,
&desc->segments, node) {
@@ -632,6 +717,12 @@ static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
sizeof(struct xilinx_axidma_tx_segment),
__alignof__(struct xilinx_axidma_tx_segment),
0);
+ } else if (chan->xdev->dmatype == XDMA_TYPE_CDMA) {
+ chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
+ chan->dev,
+ sizeof(struct xilinx_cdma_tx_segment),
+ __alignof__(struct xilinx_cdma_tx_segment),
+ 0);
} else {
chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
chan->dev,
@@ -668,6 +759,10 @@ static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
XILINX_DMA_DMAXR_ALL_IRQ_MASK);
}
+ if ((chan->xdev->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
+ dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
+ XILINX_CDMA_CR_SGMODE);
+
return 0;
}
@@ -921,6 +1016,66 @@ static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
}
/**
+ * xilinx_cdma_start_transfer - Starts cdma transfer
+ * @chan: Driver specific channel struct pointer
+ */
+static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
+{
+ struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
+ struct xilinx_cdma_tx_segment *tail_segment;
+ u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
+
+ if (chan->err)
+ return;
+
+ if (list_empty(&chan->pending_list))
+ return;
+
+ head_desc = list_first_entry(&chan->pending_list,
+ struct xilinx_dma_tx_descriptor, node);
+ tail_desc = list_last_entry(&chan->pending_list,
+ struct xilinx_dma_tx_descriptor, node);
+ tail_segment = list_last_entry(&tail_desc->segments,
+ struct xilinx_cdma_tx_segment, node);
+
+ if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
+ ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
+ ctrl_reg |= chan->desc_pendingcount <<
+ XILINX_DMA_CR_COALESCE_SHIFT;
+ dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
+ }
+
+ if (chan->has_sg) {
+ dma_ctrl_write(chan, XILINX_DMA_REG_CURDESC,
+ head_desc->async_tx.phys);
+
+ /* Update tail ptr register which will start the transfer */
+ dma_ctrl_write(chan, XILINX_DMA_REG_TAILDESC,
+ tail_segment->phys);
+ } else {
+ /* In simple mode */
+ struct xilinx_cdma_tx_segment *segment;
+ struct xilinx_cdma_desc_hw *hw;
+
+ segment = list_first_entry(&head_desc->segments,
+ struct xilinx_cdma_tx_segment,
+ node);
+
+ hw = &segment->hw;
+
+ dma_ctrl_write(chan, XILINX_CDMA_REG_SRCADDR, hw->src_addr);
+ dma_ctrl_write(chan, XILINX_CDMA_REG_DSTADDR, hw->dest_addr);
+
+ /* Start the transfer */
+ dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
+ hw->control & XILINX_DMA_MAX_TRANS_LEN);
+ }
+
+ list_splice_tail_init(&chan->pending_list, &chan->active_list);
+ chan->desc_pendingcount = 0;
+}
+
+/**
* xilinx_dma_start_transfer - Starts DMA transfer
* @chan: Driver specific channel struct pointer
*/
@@ -1166,6 +1321,7 @@ static void append_desc_queue(struct xilinx_dma_chan *chan,
struct xilinx_vdma_tx_segment *tail_segment;
struct xilinx_dma_tx_descriptor *tail_desc;
struct xilinx_axidma_tx_segment *axidma_tail_segment;
+ struct xilinx_cdma_tx_segment *cdma_tail_segment;
if (list_empty(&chan->pending_list))
goto append;
@@ -1181,6 +1337,11 @@ static void append_desc_queue(struct xilinx_dma_chan *chan,
struct xilinx_vdma_tx_segment,
node);
tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
+ } else if (chan->xdev->dmatype == XDMA_TYPE_CDMA) {
+ cdma_tail_segment = list_last_entry(&tail_desc->segments,
+ struct xilinx_cdma_tx_segment,
+ node);
+ cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
} else {
axidma_tail_segment = list_last_entry(&tail_desc->segments,
struct xilinx_axidma_tx_segment,
@@ -1324,6 +1485,68 @@ error:
}
/**
+ * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
+ * @dchan: DMA channel
+ * @dma_dst: destination address
+ * @dma_src: source address
+ * @len: transfer length
+ * @flags: transfer ack flags
+ *
+ * Return: Async transaction descriptor on success and NULL on failure
+ */
+static struct dma_async_tx_descriptor *
+xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
+ dma_addr_t dma_src, size_t len, unsigned long flags)
+{
+ struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
+ struct xilinx_dma_tx_descriptor *desc;
+ struct xilinx_cdma_tx_segment *segment, *prev;
+ struct xilinx_cdma_desc_hw *hw;
+
+ if (!len || len > XILINX_DMA_MAX_TRANS_LEN)
+ return NULL;
+
+ desc = xilinx_dma_alloc_tx_descriptor(chan);
+ if (!desc)
+ return NULL;
+
+ dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
+ desc->async_tx.tx_submit = xilinx_dma_tx_submit;
+
+ /* Allocate the link descriptor from DMA pool */
+ segment = xilinx_cdma_alloc_tx_segment(chan);
+ if (!segment)
+ goto error;
+
+ hw = &segment->hw;
+ hw->control = len;
+ hw->src_addr = dma_src;
+ hw->dest_addr = dma_dst;
+
+ /* Fill the previous next descriptor with current */
+ prev = list_last_entry(&desc->segments,
+ struct xilinx_cdma_tx_segment, node);
+ prev->hw.next_desc = segment->phys;
+
+ /* Insert the segment into the descriptor segments list. */
+ list_add_tail(&segment->node, &desc->segments);
+
+ prev = segment;
+
+ /* Link the last hardware descriptor with the first. */
+ segment = list_first_entry(&desc->segments,
+ struct xilinx_cdma_tx_segment, node);
+ desc->async_tx.phys = segment->phys;
+ prev->hw.next_desc = segment->phys;
+
+ return &desc->async_tx;
+
+error:
+ xilinx_dma_free_tx_descriptor(chan, desc);
+ return NULL;
+}
+
+/**
* xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
* @dchan: DMA channel
* @sgl: scatterlist to transfer to/from
@@ -1624,6 +1847,8 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
if (xdev->dmatype == XDMA_TYPE_AXIDMA)
chan->start_transfer = xilinx_dma_start_transfer;
+ else if (xdev->dmatype == XDMA_TYPE_CDMA)
+ chan->start_transfer = xilinx_cdma_start_transfer;
else
chan->start_transfer = xilinx_vdma_start_transfer;
@@ -1672,6 +1897,8 @@ static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
static const struct of_device_id xilinx_dma_of_ids[] = {
{ .compatible = "xlnx,axi-dma-1.00.a",
.data = (void *)XDMA_TYPE_AXIDMA },
+ { .compatible = "xlnx,axi-cdma-1.00.a",
+ .data = (void *)XDMA_TYPE_CDMA },
{ .compatible = "xlnx,axi-vdma-1.00.a",
.data = (void *)XDMA_TYPE_VDMA },
{}
@@ -1742,8 +1969,10 @@ static int xilinx_dma_probe(struct platform_device *pdev)
xdev->common.dev = &pdev->dev;
INIT_LIST_HEAD(&xdev->common.channels);
- dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
- dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
+ if (!(xdev->dmatype == XDMA_TYPE_CDMA)) {
+ dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
+ dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
+ }
xdev->common.device_alloc_chan_resources =
xilinx_dma_alloc_chan_resources;
@@ -1757,6 +1986,9 @@ static int xilinx_dma_probe(struct platform_device *pdev)
/* Residue calculation is supported by only AXI DMA */
xdev->common.residue_granularity =
DMA_RESIDUE_GRANULARITY_SEGMENT;
+ } else if (xdev->dmatype == XDMA_TYPE_CDMA) {
+ dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
+ xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
} else {
xdev->common.device_prep_interleaved_dma =
xilinx_vdma_dma_prep_interleaved;
diff --git a/include/linux/dma/xilinx_dma.h b/include/linux/dma/xilinx_dma.h
index e25872b..885b753 100644
--- a/include/linux/dma/xilinx_dma.h
+++ b/include/linux/dma/xilinx_dma.h
@@ -45,11 +45,13 @@ struct xilinx_vdma_config {
* enum xdma_ip_type: DMA IP type.
*
* XDMA_TYPE_DMA: Axi dma ip.
+ * XDMA_TYPE_CDMA: Axi cdma ip.
* XDMA_TYPE_VDMA: Axi vdma ip.
*
*/
enum xdma_ip_type {
XDMA_TYPE_AXIDMA = 0,
+ XDMA_TYPE_CDMA,
XDMA_TYPE_VDMA,
};
--
2.1.2
^ permalink raw reply related [flat|nested] 13+ messages in thread