[PATCH v6 2/2] dmaengine: Add Xilinx zynqmp dma engine driver support

Kedareswara rao Appana
2016-04-15T08:52:54Z

Added the driver for zynqmp dma engine used in Zynq
UltraScale+ MPSoC. This dma controller supports memory to memory and
memory to I/O buffer transfers.

Signed-off-by: Punnaiah Choudary Kalluri <punnaia@xilinx.com>
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
---
Changes in v6:
- Removed unnecessary axcache properties from the driver
- Fixed compilation issues
Changes in v5:
- Removed in_interrupt check from the tasklet cleanup as
suggested by the vinod/lars.
Changes in v4:
- Modified the defines to start with ZYNQMP_DMA perfix
- Changed the zynqmp_dma_alloc_chan_resources to return number of
allocated descriptors
- Changed the zynqmp_dma_device variable name
- Released the locks before calling user callback
- freeup irq in zynqmp_dma_chan_remove function.
Changes in v3:
- Modified the zynqmp_dma_chan_is_idle function return type to bool
Changes in v2:
- Corrected the function header documentation
- Framework expects bus-width value in bytes. so, fixed it
- Removed magic numbers for bus-width

drivers/dma/Kconfig | 5 +
drivers/dma/xilinx/Makefile | 1 +
drivers/dma/xilinx/zynqmp_dma.c | 1231 +++++++++++++++++++++++++++++++++++++++
3 files changed, 1237 insertions(+)
create mode 100644 drivers/dma/xilinx/zynqmp_dma.c

diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index d96d87c..dd6a38c 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -527,6 +527,11 @@ config ZX_DMA
help
Support the DMA engine for ZTE ZX296702 platform devices.

+config XILINX_ZYNQMP_DMA
+ tristate "Xilinx ZynqMP DMA Engine"
+ select DMA_ENGINE
+ help
+ Enable support for Xilinx ZynqMP DMA controller.

# driver files
source "drivers/dma/bestcomm/Kconfig"
diff --git a/drivers/dma/xilinx/Makefile b/drivers/dma/xilinx/Makefile
index 3c4e9f2..95469dc 100644
--- a/drivers/dma/xilinx/Makefile
+++ b/drivers/dma/xilinx/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_XILINX_VDMA) += xilinx_vdma.o
+obj-$(CONFIG_XILINX_ZYNQMP_DMA) += zynqmp_dma.o
diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
new file mode 100644
index 0000000..0bbc1f0
--- /dev/null
+++ b/drivers/dma/xilinx/zynqmp_dma.c
@@ -0,0 +1,1231 @@
+/*
+ * DMA driver for Xilinx ZynqMP DMA Engine
+ *
+ * Copyright (C) 2016 Xilinx, Inc. All rights reserved.
+ *
+ * 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
+ * (at your option) any later version.
+ */
+
+#include <linux/bitops.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/dmapool.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_dma.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+
+#include "../dmaengine.h"
+
+/* Register Offsets */
+#define ZYNQMP_DMA_ISR 0x100
+#define ZYNQMP_DMA_IMR 0x104
+#define ZYNQMP_DMA_IER 0x108
+#define ZYNQMP_DMA_IDS 0x10C
+#define ZYNQMP_DMA_CTRL0 0x110
+#define ZYNQMP_DMA_CTRL1 0x114
+#define ZYNQMP_DMA_DATA_ATTR 0x120
+#define ZYNQMP_DMA_DSCR_ATTR 0x124
+#define ZYNQMP_DMA_SRC_DSCR_WRD0 0x128
+#define ZYNQMP_DMA_SRC_DSCR_WRD1 0x12C
+#define ZYNQMP_DMA_SRC_DSCR_WRD2 0x130
+#define ZYNQMP_DMA_SRC_DSCR_WRD3 0x134
+#define ZYNQMP_DMA_DST_DSCR_WRD0 0x138
+#define ZYNQMP_DMA_DST_DSCR_WRD1 0x13C
+#define ZYNQMP_DMA_DST_DSCR_WRD2 0x140
+#define ZYNQMP_DMA_DST_DSCR_WRD3 0x144
+#define ZYNQMP_DMA_SRC_START_LSB 0x158
+#define ZYNQMP_DMA_SRC_START_MSB 0x15C
+#define ZYNQMP_DMA_DST_START_LSB 0x160
+#define ZYNQMP_DMA_DST_START_MSB 0x164
+#define ZYNQMP_DMA_RATE_CTRL 0x18C
+#define ZYNQMP_DMA_IRQ_SRC_ACCT 0x190
+#define ZYNQMP_DMA_IRQ_DST_ACCT 0x194
+#define ZYNQMP_DMA_CTRL2 0x200
+
+/* Interrupt registers bit field definitions */
+#define ZYNQMP_DMA_DONE BIT(10)
+#define ZYNQMP_DMA_AXI_WR_DATA BIT(9)
+#define ZYNQMP_DMA_AXI_RD_DATA BIT(8)
+#define ZYNQMP_DMA_AXI_RD_DST_DSCR BIT(7)
+#define ZYNQMP_DMA_AXI_RD_SRC_DSCR BIT(6)
+#define ZYNQMP_DMA_IRQ_DST_ACCT_ERR BIT(5)
+#define ZYNQMP_DMA_IRQ_SRC_ACCT_ERR BIT(4)
+#define ZYNQMP_DMA_BYTE_CNT_OVRFL BIT(3)
+#define ZYNQMP_DMA_DST_DSCR_DONE BIT(2)
+#define ZYNQMP_DMA_INV_APB BIT(0)
+
+/* Control 0 register bit field definitions */
+#define ZYNQMP_DMA_OVR_FETCH BIT(7)
+#define ZYNQMP_DMA_POINT_TYPE_SG BIT(6)
+#define ZYNQMP_DMA_RATE_CTRL_EN BIT(3)
+
+/* Control 1 register bit field definitions */
+#define ZYNQMP_DMA_SRC_ISSUE GENMASK(4, 0)
+
+/* Data Attribute register bit field definitions */
+#define ZYNQMP_DMA_ARBURST GENMASK(27, 26)
+#define ZYNQMP_DMA_ARCACHE GENMASK(25, 22)
+#define ZYNQMP_DMA_ARCACHE_OFST 22
+#define ZYNQMP_DMA_ARQOS GENMASK(21, 18)
+#define ZYNQMP_DMA_ARQOS_OFST 18
+#define ZYNQMP_DMA_ARLEN GENMASK(17, 14)
+#define ZYNQMP_DMA_ARLEN_OFST 14
+#define ZYNQMP_DMA_AWBURST GENMASK(13, 12)
+#define ZYNQMP_DMA_AWCACHE GENMASK(11, 8)
+#define ZYNQMP_DMA_AWCACHE_OFST 8
+#define ZYNQMP_DMA_AWQOS GENMASK(7, 4)
+#define ZYNQMP_DMA_AWQOS_OFST 4
+#define ZYNQMP_DMA_AWLEN GENMASK(3, 0)
+#define ZYNQMP_DMA_AWLEN_OFST 0
+
+/* Descriptor Attribute register bit field definitions */
+#define ZYNQMP_DMA_AXCOHRNT BIT(8)
+#define ZYNQMP_DMA_AXCACHE GENMASK(7, 4)
+#define ZYNQMP_DMA_AXCACHE_OFST 4
+#define ZYNQMP_DMA_AXQOS GENMASK(3, 0)
+#define ZYNQMP_DMA_AXQOS_OFST 0
+
+/* Control register 2 bit field definitions */
+#define ZYNQMP_DMA_ENABLE BIT(0)
+
+/* Buffer Descriptor definitions */
+#define ZYNQMP_DMA_DESC_CTRL_STOP 0x10
+#define ZYNQMP_DMA_DESC_CTRL_COMP_INT 0x4
+#define ZYNQMP_DMA_DESC_CTRL_SIZE_256 0x2
+#define ZYNQMP_DMA_DESC_CTRL_COHRNT 0x1
+
+/* Interrupt Mask specific definitions */
+#define ZYNQMP_DMA_INT_ERR (ZYNQMP_DMA_AXI_RD_DATA | \
+ ZYNQMP_DMA_AXI_WR_DATA | \
+ ZYNQMP_DMA_AXI_RD_DST_DSCR | \
+ ZYNQMP_DMA_AXI_RD_SRC_DSCR | \
+ ZYNQMP_DMA_INV_APB)
+#define ZYNQMP_DMA_INT_OVRFL (ZYNQMP_DMA_BYTE_CNT_OVRFL | \
+ ZYNQMP_DMA_IRQ_SRC_ACCT_ERR | \
+ ZYNQMP_DMA_IRQ_DST_ACCT_ERR)
+#define ZYNQMP_DMA_INT_DONE (ZYNQMP_DMA_DONE | ZYNQMP_DMA_DST_DSCR_DONE)
+#define ZYNQMP_DMA_INT_EN_DEFAULT_MASK (ZYNQMP_DMA_INT_DONE | \
+ ZYNQMP_DMA_INT_ERR | \
+ ZYNQMP_DMA_INT_OVRFL | \
+ ZYNQMP_DMA_DST_DSCR_DONE)
+
+/* Max number of descriptors per channel */
+#define ZYNQMP_DMA_NUM_DESCS 32
+
+/* Max transfer size per descriptor */
+#define ZYNQMP_DMA_MAX_TRANS_LEN 0x40000000
+
+/* Reset values for data attributes */
+#define ZYNQMP_DMA_AXCACHE_VAL 0xF
+#define ZYNQMP_DMA_ARLEN_RST_VAL 0xF
+#define ZYNQMP_DMA_AWLEN_RST_VAL 0xF
+
+#define ZYNQMP_DMA_SRC_ISSUE_RST_VAL 0x1F
+
+#define ZYNQMP_DMA_IDS_DEFAULT_MASK 0xFFF
+
+/* Bus width in bits */
+#define ZYNQMP_DMA_BUS_WIDTH_64 64
+#define ZYNQMP_DMA_BUS_WIDTH_128 128
+
+#define ZYNQMP_DMA_DESC_SIZE(chan) (chan->desc_size)
+
+#define to_chan(chan) container_of(chan, struct zynqmp_dma_chan, \
+ common)
+#define tx_to_desc(tx) container_of(tx, struct zynqmp_dma_desc_sw, \
+ async_tx)
+
+/**
+ * struct zynqmp_dma_desc_ll - Hw linked list descriptor
+ * @addr: Buffer address
+ * @size: Size of the buffer
+ * @ctrl: Control word
+ * @nxtdscraddr: Next descriptor base address
+ * @rsvd: Reserved field and for Hw internal use.
+ */
+struct zynqmp_dma_desc_ll {
+ u64 addr;
+ u32 size;
+ u32 ctrl;
+ u64 nxtdscraddr;
+ u64 rsvd;
+}; __aligned(64)
+
+/**
+ * struct zynqmp_dma_desc_sw - Per Transaction structure
+ * @src: Source address for simple mode dma
+ * @dst: Destination address for simple mode dma
+ * @len: Transfer length for simple mode dma
+ * @node: Node in the channel descriptor list
+ * @tx_list: List head for the current transfer
+ * @async_tx: Async transaction descriptor
+ * @src_v: Virtual address of the src descriptor
+ * @src_p: Physical address of the src descriptor
+ * @dst_v: Virtual address of the dst descriptor
+ * @dst_p: Physical address of the dst descriptor
+ */
+struct zynqmp_dma_desc_sw {
+ u64 src;
+ u64 dst;
+ u32 len;
+ struct list_head node;
+ struct list_head tx_list;
+ struct dma_async_tx_descriptor async_tx;
+ struct zynqmp_dma_desc_ll *src_v;
+ dma_addr_t src_p;
+ struct zynqmp_dma_desc_ll *dst_v;
+ dma_addr_t dst_p;
+};
+
+/**
+ * struct zynqmp_dma_chan - Driver specific DMA channel structure
+ * @zdev: Driver specific device structure
+ * @regs: Control registers offset
+ * @lock: Descriptor operation lock
+ * @pending_list: Descriptors waiting
+ * @free_list: Descriptors free
+ * @active_list: Descriptors active
+ * @sw_desc_pool: SW descriptor pool
+ * @done_list: Complete descriptors
+ * @common: DMA common channel
+ * @desc_pool_v: Statically allocated descriptor base
+ * @desc_pool_p: Physical allocated descriptor base
+ * @desc_free_cnt: Descriptor available count
+ * @dev: The dma device
+ * @irq: Channel IRQ
+ * @has_sg: Support scatter gather transfers
+ * @ovrfetch: Overfetch status
+ * @is_dmacoherent: Tells whether dma operations are coherent or not
+ * @ratectrl: Rate control value
+ * @tasklet: Cleanup work after irq
+ * @src_issue: Out standing transactions on source
+ * @idle : Channel status;
+ * @desc_size: Size of the low level descriptor
+ * @err: Channel has errors
+ * @bus_width: Bus width
+ * @src_burst_len: Source burst length
+ * @dst_burst_len: Dest burst length
+ * @clk_main: Pointer to main clock
+ * @clk_apb: Pointer to apb clock
+ */
+struct zynqmp_dma_chan {
+ struct zynqmp_dma_device *zdev;
+ void __iomem *regs;
+ spinlock_t lock;
+ struct list_head pending_list;
+ struct list_head free_list;
+ struct list_head active_list;
+ struct zynqmp_dma_desc_sw *sw_desc_pool;
+ struct list_head done_list;
+ struct dma_chan common;
+ void *desc_pool_v;
+ dma_addr_t desc_pool_p;
+ u32 desc_free_cnt;
+ struct device *dev;
+ int irq;
+ bool has_sg;
+ bool ovrfetch;
+ bool is_dmacoherent;
+ u32 ratectrl;
+ struct tasklet_struct tasklet;
+ u32 src_issue;
+ bool idle;
+ u32 desc_size;
+ bool err;
+ u32 bus_width;
+ u32 src_burst_len;
+ u32 dst_burst_len;
+ struct clk *clk_main;
+ struct clk *clk_apb;
+};
+
+/**
+ * struct zynqmp_dma_device - DMA device structure
+ * @dev: Device Structure
+ * @common: DMA device structure
+ * @chan: Driver specific DMA channel
+ */
+struct zynqmp_dma_device {
+ struct device *dev;
+ struct dma_device common;
+ struct zynqmp_dma_chan *chan;
+};
+
+/**
+ * zynqmp_dma_chan_is_idle - Provides the channel idle status
+ * @chan: ZynqMP DMA DMA channel pointer
+ *
+ * Return: 'true' if the channel is idle otherwise 'false'
+ */
+static inline bool zynqmp_dma_chan_is_idle(struct zynqmp_dma_chan *chan)
+{
+ return chan->idle;
+
+}
+
+/**
+ * zynqmp_dma_update_desc_to_ctrlr - Updates descriptor to the controller
+ * @chan: ZynqMP DMA DMA channel pointer
+ * @desc: Transaction descriptor pointer
+ */
+static void zynqmp_dma_update_desc_to_ctrlr(struct zynqmp_dma_chan *chan,
+ struct zynqmp_dma_desc_sw *desc)
+{
+ dma_addr_t addr;
+
+ addr = desc->src_p;
+ writel(addr, chan->regs + ZYNQMP_DMA_SRC_START_LSB);
+ writel(upper_32_bits(addr), chan->regs + ZYNQMP_DMA_SRC_START_MSB);
+ addr = desc->dst_p;
+ writel(addr, chan->regs + ZYNQMP_DMA_DST_START_LSB);
+ writel(upper_32_bits(addr), chan->regs + ZYNQMP_DMA_DST_START_MSB);
+}
+
+/**
+ * zynqmp_dma_desc_config_eod - Mark the descriptor as end descriptor
+ * @chan: ZynqMP DMA channel pointer
+ * @desc: Hw descriptor pointer
+ */
+static void zynqmp_dma_desc_config_eod(struct zynqmp_dma_chan *chan, void *desc)
+{
+ struct zynqmp_dma_desc_ll *hw = (struct zynqmp_dma_desc_ll *)desc;
+
+ hw->ctrl |= ZYNQMP_DMA_DESC_CTRL_STOP;
+ hw++;
+ hw->ctrl |= ZYNQMP_DMA_DESC_CTRL_COMP_INT | ZYNQMP_DMA_DESC_CTRL_STOP;
+}
+
+/**
+ * zynqmp_dma_config_simple_desc - Configure the transfer parameters
+ * @chan: ZynqMP DMA channel pointer
+ * @src: Source buffer address
+ * @dst: Destination buffer address
+ * @len: Transfer length
+ */
+static void zynqmp_dma_config_simple_desc(struct zynqmp_dma_chan *chan,
+ dma_addr_t src, dma_addr_t dst,
+ size_t len)
+{
+ u32 val;
+
+ writel(src, chan->regs + ZYNQMP_DMA_SRC_DSCR_WRD0);
+ writel(upper_32_bits(src), chan->regs + ZYNQMP_DMA_SRC_DSCR_WRD1);
+ writel(len, chan->regs + ZYNQMP_DMA_SRC_DSCR_WRD2);
+
+ if (chan->is_dmacoherent)
+ writel(ZYNQMP_DMA_DESC_CTRL_COHRNT,
+ chan->regs + ZYNQMP_DMA_SRC_DSCR_WRD3);
+ else
+ writel(0, chan->regs + ZYNQMP_DMA_SRC_DSCR_WRD3);
+
+ writel(dst, chan->regs + ZYNQMP_DMA_DST_DSCR_WRD0);
+ writel(upper_32_bits(dst), chan->regs + ZYNQMP_DMA_DST_DSCR_WRD1);
+ writel(len, chan->regs + ZYNQMP_DMA_DST_DSCR_WRD2);
+
+ if (chan->is_dmacoherent)
+ val = ZYNQMP_DMA_DESC_CTRL_COHRNT |
+ ZYNQMP_DMA_DESC_CTRL_COMP_INT;
+ else
+ val = ZYNQMP_DMA_DESC_CTRL_COMP_INT;
+ writel(val, chan->regs + ZYNQMP_DMA_DST_DSCR_WRD3);
+}
+
+/**
+ * zynqmp_dma_config_sg_ll_desc - Configure the linked list descriptor
+ * @chan: ZynqMP DMA channel pointer
+ * @sdesc: Hw descriptor pointer
+ * @src: Source buffer address
+ * @dst: Destination buffer address
+ * @len: Transfer length
+ * @prev: Previous hw descriptor pointer
+ */
+static void zynqmp_dma_config_sg_ll_desc(struct zynqmp_dma_chan *chan,
+ struct zynqmp_dma_desc_ll *sdesc,
+ dma_addr_t src, dma_addr_t dst, size_t len,
+ struct zynqmp_dma_desc_ll *prev)
+{
+ struct zynqmp_dma_desc_ll *ddesc = sdesc + 1;
+
+ sdesc->size = ddesc->size = len;
+ sdesc->addr = src;
+ ddesc->addr = dst;
+
+ sdesc->ctrl = ddesc->ctrl = ZYNQMP_DMA_DESC_CTRL_SIZE_256;
+ if (chan->is_dmacoherent) {
+ sdesc->ctrl |= ZYNQMP_DMA_DESC_CTRL_COHRNT;
+ ddesc->ctrl |= ZYNQMP_DMA_DESC_CTRL_COHRNT;
+ }
+
+ if (prev) {
+ dma_addr_t addr = chan->desc_pool_p +
+ ((dma_addr_t)sdesc - (dma_addr_t)chan->desc_pool_v);
+ ddesc = prev + 1;
+ prev->nxtdscraddr = addr;
+ ddesc->nxtdscraddr = addr + ZYNQMP_DMA_DESC_SIZE(chan);
+ }
+}
+
+/**
+ * zynqmp_dma_init - Initialize the channel
+ * @chan: ZynqMP DMA channel pointer
+ */
+static void zynqmp_dma_init(struct zynqmp_dma_chan *chan)
+{
+ u32 val;
+
+ writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
+ val = readl(chan->regs + ZYNQMP_DMA_ISR);
+ writel(val, chan->regs + ZYNQMP_DMA_ISR);
+
+ val = readl(chan->regs + ZYNQMP_DMA_CTRL1);
+ if (chan->src_issue)
+ val = (val & ~ZYNQMP_DMA_SRC_ISSUE) | chan->src_issue;
+ writel(val, chan->regs + ZYNQMP_DMA_CTRL1);
+
+ val = 0;
+ if (chan->ovrfetch)
+ val |= ZYNQMP_DMA_OVR_FETCH;
+ if (chan->has_sg)
+ val |= ZYNQMP_DMA_POINT_TYPE_SG;
+ if (chan->ratectrl) {
+ val |= ZYNQMP_DMA_RATE_CTRL_EN;
+ writel(chan->ratectrl, chan->regs + ZYNQMP_DMA_RATE_CTRL);
+ }
+ writel(val, chan->regs + ZYNQMP_DMA_CTRL0);
+
+ val = 0;
+ if (chan->is_dmacoherent) {
+ val |= ZYNQMP_DMA_AXCOHRNT;
+ val = (val & ~ZYNQMP_DMA_AXCACHE) |
+ (ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_AXCACHE_OFST);
+ }
+ writel(val, chan->regs + ZYNQMP_DMA_DSCR_ATTR);
+
+ val = readl(chan->regs + ZYNQMP_DMA_DATA_ATTR);
+ if (chan->is_dmacoherent) {
+ val = (val & ~ZYNQMP_DMA_ARCACHE) |
+ (ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_ARCACHE_OFST);
+ val = (val & ~ZYNQMP_DMA_AWCACHE) |
+ (ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_AWCACHE_OFST);
+ }
+ val = (val & ~ZYNQMP_DMA_ARLEN) |
+ (chan->src_burst_len << ZYNQMP_DMA_ARLEN_OFST);
+ val = (val & ~ZYNQMP_DMA_AWLEN) |
+ (chan->dst_burst_len << ZYNQMP_DMA_AWLEN_OFST);
+ writel(val, chan->regs + ZYNQMP_DMA_DATA_ATTR);
+
+ /* Clearing the interrupt account rgisters */
+ val = readl(chan->regs + ZYNQMP_DMA_IRQ_SRC_ACCT);
+ val = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
+
+ chan->idle = true;
+}
+
+/**
+ * zynqmp_dma_tx_submit - Submit DMA transaction
+ * @tx: Async transaction descriptor pointer
+ *
+ * Return: cookie value
+ */
+static dma_cookie_t zynqmp_dma_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct zynqmp_dma_chan *chan = to_chan(tx->chan);
+ struct zynqmp_dma_desc_sw *desc, *new;
+ dma_cookie_t cookie;
+
+ new = tx_to_desc(tx);
+ spin_lock_bh(&chan->lock);
+ cookie = dma_cookie_assign(tx);
+
+ if (!list_empty(&chan->pending_list) && chan->has_sg) {
+ desc = list_last_entry(&chan->pending_list,
+ struct zynqmp_dma_desc_sw, node);
+ if (!list_empty(&desc->tx_list))
+ desc = list_last_entry(&desc->tx_list,
+ struct zynqmp_dma_desc_sw, node);
+ desc->src_v->nxtdscraddr = new->src_p;
+ desc->src_v->ctrl &= ~ZYNQMP_DMA_DESC_CTRL_STOP;
+ desc->dst_v->nxtdscraddr = new->dst_p;
+ desc->dst_v->ctrl &= ~ZYNQMP_DMA_DESC_CTRL_STOP;
+ }
+
+ list_add_tail(&new->node, &chan->pending_list);
+ spin_unlock_bh(&chan->lock);
+
+ return cookie;
+}
+
+/**
+ * zynqmp_dma_get_descriptor - Get the sw descriptor from the pool
+ * @chan: ZynqMP DMA channel pointer
+ *
+ * Return: The sw descriptor
+ */
+static struct zynqmp_dma_desc_sw *
+zynqmp_dma_get_descriptor(struct zynqmp_dma_chan *chan)
+{
+ struct zynqmp_dma_desc_sw *desc;
+
+ spin_lock_bh(&chan->lock);
+ desc = list_first_entry(&chan->free_list, struct zynqmp_dma_desc_sw,
+ node);
+ list_del(&desc->node);
+ spin_unlock_bh(&chan->lock);
+
+ INIT_LIST_HEAD(&desc->tx_list);
+ /* Clear the src and dst descriptor memory */
+ if (chan->has_sg) {
+ memset((void *)desc->src_v, 0, ZYNQMP_DMA_DESC_SIZE(chan));
+ memset((void *)desc->dst_v, 0, ZYNQMP_DMA_DESC_SIZE(chan));
+ }
+
+ return desc;
+}
+
+/**
+ * zynqmp_dma_free_descriptor - Issue pending transactions
+ * @chan: ZynqMP DMA channel pointer
+ * @sdesc: Transaction descriptor pointer
+ */
+static void zynqmp_dma_free_descriptor(struct zynqmp_dma_chan *chan,
+ struct zynqmp_dma_desc_sw *sdesc)
+{
+ struct zynqmp_dma_desc_sw *child, *next;
+
+ chan->desc_free_cnt++;
+ list_add_tail(&sdesc->node, &chan->free_list);
+ list_for_each_entry_safe(child, next, &sdesc->tx_list, node) {
+ chan->desc_free_cnt++;
+ INIT_LIST_HEAD(&child->tx_list);
+ list_move_tail(&child->node, &chan->free_list);
+ }
+ INIT_LIST_HEAD(&sdesc->tx_list);
+}
+
+/**
+ * zynqmp_dma_free_desc_list - Free descriptors list
+ * @chan: ZynqMP DMA channel pointer
+ * @list: List to parse and delete the descriptor
+ */
+static void zynqmp_dma_free_desc_list(struct zynqmp_dma_chan *chan,
+ struct list_head *list)
+{
+ struct zynqmp_dma_desc_sw *desc, *next;
+
+ list_for_each_entry_safe(desc, next, list, node)
+ zynqmp_dma_free_descriptor(chan, desc);
+}
+
+/**
+ * zynqmp_dma_alloc_chan_resources - Allocate channel resources
+ * @dchan: DMA channel
+ *
+ * Return: Number of descriptors on success and failure value on error
+ */
+static int zynqmp_dma_alloc_chan_resources(struct dma_chan *dchan)
+{
+ struct zynqmp_dma_chan *chan = to_chan(dchan);
+ struct zynqmp_dma_desc_sw *desc;
+ int i;
+
+ chan->sw_desc_pool = kzalloc(sizeof(*desc) * ZYNQMP_DMA_NUM_DESCS,
+ GFP_KERNEL);
+ if (!chan->sw_desc_pool)
+ return -ENOMEM;
+ chan->idle = true;
+ chan->desc_free_cnt = ZYNQMP_DMA_NUM_DESCS;
+
+ INIT_LIST_HEAD(&chan->free_list);
+
+ for (i = 0; i < ZYNQMP_DMA_NUM_DESCS; i++) {
+ desc = chan->sw_desc_pool + i;
+ dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
+ desc->async_tx.tx_submit = zynqmp_dma_tx_submit;
+ list_add_tail(&desc->node, &chan->free_list);
+ }
+
+ if (!chan->has_sg)
+ return 0;
+
+ chan->desc_pool_v = dma_zalloc_coherent(chan->dev,
+ (2 * chan->desc_size * ZYNQMP_DMA_NUM_DESCS),
+ &chan->desc_pool_p, GFP_KERNEL);
+ if (!chan->desc_pool_v)
+ return -ENOMEM;
+
+ for (i = 0; i < ZYNQMP_DMA_NUM_DESCS; i++) {
+ desc = chan->sw_desc_pool + i;
+ desc->src_v = (struct zynqmp_dma_desc_ll *) (chan->desc_pool_v +
+ (i * ZYNQMP_DMA_DESC_SIZE(chan) * 2));
+ desc->dst_v = (struct zynqmp_dma_desc_ll *) (desc->src_v + 1);
+ desc->src_p = chan->desc_pool_p +
+ (i * ZYNQMP_DMA_DESC_SIZE(chan) * 2);
+ desc->dst_p = desc->src_p + ZYNQMP_DMA_DESC_SIZE(chan);
+ }
+
+ return ZYNQMP_DMA_NUM_DESCS;
+}
+
+/**
+ * zynqmp_dma_start - Start DMA channel
+ * @chan: ZynqMP DMA channel pointer
+ */
+static void zynqmp_dma_start(struct zynqmp_dma_chan *chan)
+{
+ writel(ZYNQMP_DMA_INT_EN_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IER);
+ chan->idle = false;
+ writel(ZYNQMP_DMA_ENABLE, chan->regs + ZYNQMP_DMA_CTRL2);
+}
+
+/**
+ * zynqmp_dma_handle_ovfl_int - Process the overflow interrupt
+ * @chan: ZynqMP DMA channel pointer
+ * @status: Interrupt status value
+ */
+static void zynqmp_dma_handle_ovfl_int(struct zynqmp_dma_chan *chan, u32 status)
+{
+ u32 val;
+
+ if (status & ZYNQMP_DMA_IRQ_DST_ACCT_ERR)
+ val = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
+ if (status & ZYNQMP_DMA_IRQ_SRC_ACCT_ERR)
+ val = readl(chan->regs + ZYNQMP_DMA_IRQ_SRC_ACCT);
+}
+
+/**
+ * zynqmp_dma_start_transfer - Initiate the new transfer
+ * @chan: ZynqMP DMA channel pointer
+ */
+static void zynqmp_dma_start_transfer(struct zynqmp_dma_chan *chan)
+{
+ struct zynqmp_dma_desc_sw *desc;
+
+ if (!zynqmp_dma_chan_is_idle(chan))
+ return;
+
+ desc = list_first_entry_or_null(&chan->pending_list,
+ struct zynqmp_dma_desc_sw, node);
+ if (!desc)
+ return;
+
+ if (chan->has_sg)
+ list_splice_tail_init(&chan->pending_list, &chan->active_list);
+ else
+ list_move_tail(&desc->node, &chan->active_list);
+
+ if (chan->has_sg)
+ zynqmp_dma_update_desc_to_ctrlr(chan, desc);
+ else
+ zynqmp_dma_config_simple_desc(chan, desc->src, desc->dst,
+ desc->len);
+
+ zynqmp_dma_start(chan);
+}
+
+
+/**
+ * zynqmp_dma_chan_desc_cleanup - Cleanup the completed descriptors
+ * @chan: ZynqMP DMA channel
+ */
+static void zynqmp_dma_chan_desc_cleanup(struct zynqmp_dma_chan *chan)
+{
+ struct zynqmp_dma_desc_sw *desc, *next;
+
+ list_for_each_entry_safe(desc, next, &chan->done_list, node) {
+ dma_async_tx_callback callback;
+ void *callback_param;
+
+ list_del(&desc->node);
+
+ callback = desc->async_tx.callback;
+ callback_param = desc->async_tx.callback_param;
+ if (callback) {
+ spin_unlock(&chan->lock);
+ callback(callback_param);
+ spin_lock(&chan->lock);
+ }
+
+ /* Run any dependencies, then free the descriptor */
+ zynqmp_dma_free_descriptor(chan, desc);
+ }
+}
+
+/**
+ * zynqmp_dma_complete_descriptor - Mark the active descriptor as complete
+ * @chan: ZynqMP DMA channel pointer
+ */
+static void zynqmp_dma_complete_descriptor(struct zynqmp_dma_chan *chan)
+{
+ struct zynqmp_dma_desc_sw *desc;
+
+ desc = list_first_entry_or_null(&chan->active_list,
+ struct zynqmp_dma_desc_sw, node);
+ if (!desc)
+ return;
+ list_del(&desc->node);
+ dma_cookie_complete(&desc->async_tx);
+ list_add_tail(&desc->node, &chan->done_list);
+}
+
+/**
+ * zynqmp_dma_issue_pending - Issue pending transactions
+ * @dchan: DMA channel pointer
+ */
+static void zynqmp_dma_issue_pending(struct dma_chan *dchan)
+{
+ struct zynqmp_dma_chan *chan = to_chan(dchan);
+
+ spin_lock_bh(&chan->lock);
+ zynqmp_dma_start_transfer(chan);
+ spin_unlock_bh(&chan->lock);
+}
+
+/**
+ * zynqmp_dma_free_descriptors - Free channel descriptors
+ * @dchan: DMA channel pointer
+ */
+static void zynqmp_dma_free_descriptors(struct zynqmp_dma_chan *chan)
+{
+ zynqmp_dma_free_desc_list(chan, &chan->active_list);
+ zynqmp_dma_free_desc_list(chan, &chan->pending_list);
+ zynqmp_dma_free_desc_list(chan, &chan->done_list);
+}
+
+/**
+ * zynqmp_dma_free_chan_resources - Free channel resources
+ * @dchan: DMA channel pointer
+ */
+static void zynqmp_dma_free_chan_resources(struct dma_chan *dchan)
+{
+ struct zynqmp_dma_chan *chan = to_chan(dchan);
+
+ spin_lock_bh(&chan->lock);
+ zynqmp_dma_free_descriptors(chan);
+ spin_unlock_bh(&chan->lock);
+ dma_free_coherent(chan->dev,
+ (2 * ZYNQMP_DMA_DESC_SIZE(chan) * ZYNQMP_DMA_NUM_DESCS),
+ chan->desc_pool_v, chan->desc_pool_p);
+ kfree(chan->sw_desc_pool);
+}
+
+/**
+ * zynqmp_dma_tx_status - Get dma transaction status
+ * @dchan: DMA channel pointer
+ * @cookie: Transaction identifier
+ * @txstate: Transaction state
+ *
+ * Return: DMA transaction status
+ */
+static enum dma_status zynqmp_dma_tx_status(struct dma_chan *dchan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ return dma_cookie_status(dchan, cookie, txstate);
+}
+
+/**
+ * zynqmp_dma_reset - Reset the channel
+ * @chan: ZynqMP DMA channel pointer
+ */
+static void zynqmp_dma_reset(struct zynqmp_dma_chan *chan)
+{
+ writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
+
+ zynqmp_dma_complete_descriptor(chan);
+ zynqmp_dma_chan_desc_cleanup(chan);
+ zynqmp_dma_free_descriptors(chan);
+ zynqmp_dma_init(chan);
+}
+
+/**
+ * zynqmp_dma_irq_handler - ZynqMP DMA Interrupt handler
+ * @irq: IRQ number
+ * @data: Pointer to the ZynqMP DMA channel structure
+ *
+ * Return: IRQ_HANDLED/IRQ_NONE
+ */
+static irqreturn_t zynqmp_dma_irq_handler(int irq, void *data)
+{
+ struct zynqmp_dma_chan *chan = (struct zynqmp_dma_chan *)data;
+ u32 isr, imr, status;
+ irqreturn_t ret = IRQ_NONE;
+
+ isr = readl(chan->regs + ZYNQMP_DMA_ISR);
+ imr = readl(chan->regs + ZYNQMP_DMA_IMR);
+ status = isr & ~imr;
+
+ writel(isr, chan->regs + ZYNQMP_DMA_ISR);
+ if (status & ZYNQMP_DMA_INT_DONE) {
+ tasklet_schedule(&chan->tasklet);
+ ret = IRQ_HANDLED;
+ }
+
+ if (status & ZYNQMP_DMA_DONE)
+ chan->idle = true;
+
+ if (status & ZYNQMP_DMA_INT_ERR) {
+ chan->err = true;
+ tasklet_schedule(&chan->tasklet);
+ dev_err(chan->dev, "Channel %p has errors\n", chan);
+ ret = IRQ_HANDLED;
+ }
+
+ if (status & ZYNQMP_DMA_INT_OVRFL) {
+ zynqmp_dma_handle_ovfl_int(chan, status);
+ dev_info(chan->dev, "Channel %p overflow interrupt\n", chan);
+ ret = IRQ_HANDLED;
+ }
+
+ return ret;
+}
+
+/**
+ * zynqmp_dma_do_tasklet - Schedule completion tasklet
+ * @data: Pointer to the ZynqMP DMA channel structure
+ */
+static void zynqmp_dma_do_tasklet(unsigned long data)
+{
+ struct zynqmp_dma_chan *chan = (struct zynqmp_dma_chan *)data;
+ u32 count;
+
+ spin_lock(&chan->lock);
+
+ if (chan->err) {
+ zynqmp_dma_reset(chan);
+ chan->err = false;
+ goto unlock;
+ }
+
+ count = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
+
+ while (count) {
+ zynqmp_dma_complete_descriptor(chan);
+ zynqmp_dma_chan_desc_cleanup(chan);
+ count--;
+ }
+
+ if (chan->idle)
+ zynqmp_dma_start_transfer(chan);
+
+unlock:
+ spin_unlock(&chan->lock);
+}
+
+/**
+ * zynqmp_dma_device_terminate_all - Aborts all transfers on a channel
+ * @dchan: DMA channel pointer
+ *
+ * Return: Always '0'
+ */
+static int zynqmp_dma_device_terminate_all(struct dma_chan *dchan)
+{
+ struct zynqmp_dma_chan *chan = to_chan(dchan);
+
+ spin_lock_bh(&chan->lock);
+ writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
+ zynqmp_dma_free_descriptors(chan);
+ spin_unlock_bh(&chan->lock);
+
+ return 0;
+}
+
+/**
+ * zynqmp_dma_prep_memcpy - prepare descriptors for memcpy transaction
+ * @dchan: DMA channel
+ * @dma_dst: Destination buffer address
+ * @dma_src: Source buffer address
+ * @len: Transfer length
+ * @flags: transfer ack flags
+ *
+ * Return: Async transaction descriptor on success and NULL on failure
+ */
+static struct dma_async_tx_descriptor *zynqmp_dma_prep_memcpy(
+ struct dma_chan *dchan, dma_addr_t dma_dst,
+ dma_addr_t dma_src, size_t len, ulong flags)
+{
+ struct zynqmp_dma_chan *chan;
+ struct zynqmp_dma_desc_sw *new, *first = NULL;
+ void *desc = NULL, *prev = NULL;
+ size_t copy;
+ u32 desc_cnt;
+
+ chan = to_chan(dchan);
+
+ if ((len > ZYNQMP_DMA_MAX_TRANS_LEN) && !chan->has_sg)
+ return NULL;
+
+ desc_cnt = DIV_ROUND_UP(len, ZYNQMP_DMA_MAX_TRANS_LEN);
+
+ spin_lock_bh(&chan->lock);
+ if ((desc_cnt > chan->desc_free_cnt) && chan->has_sg) {
+ spin_unlock_bh(&chan->lock);
+ dev_dbg(chan->dev, "chan %p descs are not available\n", chan);
+ return NULL;
+ }
+ chan->desc_free_cnt = chan->desc_free_cnt - desc_cnt;
+ spin_unlock_bh(&chan->lock);
+
+ do {
+ /* Allocate and populate the descriptor */
+ new = zynqmp_dma_get_descriptor(chan);
+
+ copy = min_t(size_t, len, ZYNQMP_DMA_MAX_TRANS_LEN);
+ if (chan->has_sg) {
+ desc = (struct zynqmp_dma_desc_ll *)new->src_v;
+ zynqmp_dma_config_sg_ll_desc(chan, desc, dma_src,
+ dma_dst, copy, prev);
+ } else {
+ new->src = dma_src;
+ new->dst = dma_dst;
+ new->len = len;
+ }
+
+ prev = desc;
+ len -= copy;
+ dma_src += copy;
+ dma_dst += copy;
+ if (!first)
+ first = new;
+ else
+ list_add_tail(&new->node, &first->tx_list);
+ } while (len);
+
+ if (chan->has_sg)
+ zynqmp_dma_desc_config_eod(chan, desc);
+
+ async_tx_ack(&first->async_tx);
+ first->async_tx.flags = flags;
+ return &first->async_tx;
+}
+
+/**
+ * zynqmp_dma_prep_slave_sg - prepare descriptors for a memory sg transaction
+ * @dchan: DMA channel
+ * @dst_sg: Destination scatter list
+ * @dst_sg_len: Number of entries in destination scatter list
+ * @src_sg: Source scatter list
+ * @src_sg_len: Number of entries in source scatter list
+ * @flags: transfer ack flags
+ *
+ * Return: Async transaction descriptor on success and NULL on failure
+ */
+static struct dma_async_tx_descriptor *zynqmp_dma_prep_sg(
+ struct dma_chan *dchan, struct scatterlist *dst_sg,
+ unsigned int dst_sg_len, struct scatterlist *src_sg,
+ unsigned int src_sg_len, unsigned long flags)
+{
+ struct zynqmp_dma_desc_sw *new, *first = NULL;
+ struct zynqmp_dma_chan *chan = to_chan(dchan);
+ void *desc = NULL, *prev = NULL;
+ size_t len, dst_avail, src_avail;
+ dma_addr_t dma_dst, dma_src;
+ u32 desc_cnt = 0, i;
+ struct scatterlist *sg;
+
+ if (!chan->has_sg)
+ return NULL;
+
+ for_each_sg(src_sg, sg, src_sg_len, i)
+ desc_cnt += DIV_ROUND_UP(sg_dma_len(sg),
+ ZYNQMP_DMA_MAX_TRANS_LEN);
+
+ spin_lock_bh(&chan->lock);
+ if (desc_cnt > chan->desc_free_cnt) {
+ spin_unlock_bh(&chan->lock);
+ dev_dbg(chan->dev, "chan %p descs are not available\n", chan);
+ return NULL;
+ }
+ chan->desc_free_cnt = chan->desc_free_cnt - desc_cnt;
+ spin_unlock_bh(&chan->lock);
+
+ dst_avail = sg_dma_len(dst_sg);
+ src_avail = sg_dma_len(src_sg);
+
+ /* Run until we are out of scatterlist entries */
+ while (true) {
+ /* Allocate and populate the descriptor */
+ new = zynqmp_dma_get_descriptor(chan);
+ desc = (struct zynqmp_dma_desc_ll *)new->src_v;
+ len = min_t(size_t, src_avail, dst_avail);
+ len = min_t(size_t, len, ZYNQMP_DMA_MAX_TRANS_LEN);
+ if (len == 0)
+ goto fetch;
+ dma_dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) -
+ dst_avail;
+ dma_src = sg_dma_address(src_sg) + sg_dma_len(src_sg) -
+ src_avail;
+
+ zynqmp_dma_config_sg_ll_desc(chan, desc, dma_src, dma_dst,
+ len, prev);
+ prev = desc;
+ dst_avail -= len;
+ src_avail -= len;
+
+ if (!first)
+ first = new;
+ else
+ list_add_tail(&new->node, &first->tx_list);
+fetch:
+ /* Fetch the next dst scatterlist entry */
+ if (dst_avail == 0) {
+ if (dst_sg_len == 0)
+ break;
+ dst_sg = sg_next(dst_sg);
+ if (dst_sg == NULL)
+ break;
+ dst_sg_len--;
+ dst_avail = sg_dma_len(dst_sg);
+ }
+ /* Fetch the next src scatterlist entry */
+ if (src_avail == 0) {
+ if (src_sg_len == 0)
+ break;
+ src_sg = sg_next(src_sg);
+ if (src_sg == NULL)
+ break;
+ src_sg_len--;
+ src_avail = sg_dma_len(src_sg);
+ }
+ }
+
+ zynqmp_dma_desc_config_eod(chan, desc);
+ first->async_tx.flags = flags;
+ return &first->async_tx;
+}
+
+/**
+ * zynqmp_dma_chan_remove - Channel remove function
+ * @chan: ZynqMP DMA channel pointer
+ */
+static void zynqmp_dma_chan_remove(struct zynqmp_dma_chan *chan)
+{
+ if (!chan)
+ return;
+
+ devm_free_irq(chan->zdev->dev, chan->irq, chan);
+ tasklet_kill(&chan->tasklet);
+ list_del(&chan->common.device_node);
+ clk_disable_unprepare(chan->clk_apb);
+ clk_disable_unprepare(chan->clk_main);
+}
+
+/**
+ * zynqmp_dma_chan_probe - Per Channel Probing
+ * @zdev: Driver specific device structure
+ * @pdev: Pointer to the platform_device structure
+ *
+ * Return: '0' on success and failure value on error
+ */
+static int zynqmp_dma_chan_probe(struct zynqmp_dma_device *zdev,
+ struct platform_device *pdev)
+{
+ struct zynqmp_dma_chan *chan;
+ struct resource *res;
+ struct device_node *node = pdev->dev.of_node;
+ int err;
+
+ chan = devm_kzalloc(zdev->dev, sizeof(*chan), GFP_KERNEL);
+ if (!chan)
+ return -ENOMEM;
+ chan->dev = zdev->dev;
+ chan->zdev = zdev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ chan->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(chan->regs))
+ return PTR_ERR(chan->regs);
+
+ chan->bus_width = ZYNQMP_DMA_BUS_WIDTH_64;
+ chan->src_issue = ZYNQMP_DMA_SRC_ISSUE_RST_VAL;
+ chan->dst_burst_len = ZYNQMP_DMA_AWLEN_RST_VAL;
+ chan->src_burst_len = ZYNQMP_DMA_ARLEN_RST_VAL;
+ err = of_property_read_u32(node, "xlnx,bus-width", &chan->bus_width);
+ if ((err < 0) && ((chan->bus_width != ZYNQMP_DMA_BUS_WIDTH_64) ||
+ (chan->bus_width != ZYNQMP_DMA_BUS_WIDTH_128))) {
+ dev_err(zdev->dev, "invalid bus-width value");
+ return err;
+ }
+
+ chan->has_sg = of_property_read_bool(node, "xlnx,include-sg");
+ chan->ovrfetch = of_property_read_bool(node, "xlnx,overfetch");
+ chan->is_dmacoherent = of_property_read_bool(node, "dma-coherent");
+ of_property_read_u32(node, "xlnx,src-burst-len", &chan->src_burst_len);
+ of_property_read_u32(node, "xlnx,dst-burst-len", &chan->dst_burst_len);
+ of_property_read_u32(node, "xlnx,ratectrl", &chan->ratectrl);
+ of_property_read_u32(node, "xlnx,src-issue", &chan->src_issue);
+
+ zdev->chan = chan;
+ tasklet_init(&chan->tasklet, zynqmp_dma_do_tasklet, (ulong)chan);
+ spin_lock_init(&chan->lock);
+ INIT_LIST_HEAD(&chan->active_list);
+ INIT_LIST_HEAD(&chan->pending_list);
+ INIT_LIST_HEAD(&chan->done_list);
+ INIT_LIST_HEAD(&chan->free_list);
+
+ dma_cookie_init(&chan->common);
+ chan->common.device = &zdev->common;
+ list_add_tail(&chan->common.device_node, &zdev->common.channels);
+
+ zynqmp_dma_init(chan);
+ chan->irq = platform_get_irq(pdev, 0);
+ if (chan->irq < 0)
+ return -ENXIO;
+ err = devm_request_irq(&pdev->dev, chan->irq, zynqmp_dma_irq_handler, 0,
+ "zynqmp-dma", chan);
+ if (err)
+ return err;
+ chan->clk_main = devm_clk_get(&pdev->dev, "clk_main");
+ if (IS_ERR(chan->clk_main)) {
+ dev_err(&pdev->dev, "main clock not found.\n");
+ return PTR_ERR(chan->clk_main);
+ }
+
+ chan->clk_apb = devm_clk_get(&pdev->dev, "clk_apb");
+ if (IS_ERR(chan->clk_apb)) {
+ dev_err(&pdev->dev, "apb clock not found.\n");
+ return PTR_ERR(chan->clk_apb);
+ }
+
+ err = clk_prepare_enable(chan->clk_main);
+ if (err) {
+ dev_err(&pdev->dev, "Unable to enable main clock.\n");
+ return err;
+ }
+
+ err = clk_prepare_enable(chan->clk_apb);
+ if (err) {
+ dev_err(&pdev->dev, "Unable to enable apb clock.\n");
+ return err;
+ }
+
+ chan->desc_size = sizeof(struct zynqmp_dma_desc_ll);
+ chan->idle = true;
+ return 0;
+}
+
+/**
+ * of_zynqmp_dma_xlate - Translation function
+ * @dma_spec: Pointer to DMA specifier as found in the device tree
+ * @ofdma: Pointer to DMA controller data
+ *
+ * Return: DMA channel pointer on success and NULL on error
+ */
+static struct dma_chan *of_zynqmp_dma_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct zynqmp_dma_device *zdev = ofdma->of_dma_data;
+
+ return dma_get_slave_channel(&zdev->chan->common);
+}
+
+/**
+ * zynqmp_dma_probe - Driver probe function
+ * @pdev: Pointer to the platform_device structure
+ *
+ * Return: '0' on success and failure value on error
+ */
+static int zynqmp_dma_probe(struct platform_device *pdev)
+{
+ struct zynqmp_dma_device *zdev;
+ struct dma_device *p;
+ int ret;
+
+ zdev = devm_kzalloc(&pdev->dev, sizeof(*zdev), GFP_KERNEL);
+ if (!zdev)
+ return -ENOMEM;
+
+ zdev->dev = &pdev->dev;
+ INIT_LIST_HEAD(&zdev->common.channels);
+
+ dma_set_mask(&pdev->dev, DMA_BIT_MASK(44));
+ dma_cap_set(DMA_SG, zdev->common.cap_mask);
+ dma_cap_set(DMA_MEMCPY, zdev->common.cap_mask);
+
+ p = &zdev->common;
+ p->device_prep_dma_sg = zynqmp_dma_prep_sg;
+ p->device_prep_dma_memcpy = zynqmp_dma_prep_memcpy;
+ p->device_terminate_all = zynqmp_dma_device_terminate_all;
+ p->device_issue_pending = zynqmp_dma_issue_pending;
+ p->device_alloc_chan_resources = zynqmp_dma_alloc_chan_resources;
+ p->device_free_chan_resources = zynqmp_dma_free_chan_resources;
+ p->device_tx_status = zynqmp_dma_tx_status;
+ p->dev = &pdev->dev;
+
+ platform_set_drvdata(pdev, zdev);
+
+ ret = zynqmp_dma_chan_probe(zdev, pdev);
+ if (ret) {
+ dev_err(&pdev->dev, "Probing channel failed\n");
+ goto free_chan_resources;
+ }
+
+ p->dst_addr_widths = zdev->chan->bus_width / 8;
+ p->src_addr_widths = zdev->chan->bus_width / 8;
+
+ dma_async_device_register(&zdev->common);
+
+ ret = of_dma_controller_register(pdev->dev.of_node,
+ of_zynqmp_dma_xlate, zdev);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to register DMA to DT\n");
+ dma_async_device_unregister(&zdev->common);
+ goto free_chan_resources;
+ }
+
+ dev_info(&pdev->dev, "ZynqMP DMA driver Probe success\n");
+
+ return 0;
+
+free_chan_resources:
+ zynqmp_dma_chan_remove(zdev->chan);
+ return ret;
+}
+
+/**
+ * zynqmp_dma_remove - Driver remove function
+ * @pdev: Pointer to the platform_device structure
+ *
+ * Return: Always '0'
+ */
+static int zynqmp_dma_remove(struct platform_device *pdev)
+{
+ struct zynqmp_dma_device *zdev = platform_get_drvdata(pdev);
+
+ of_dma_controller_free(pdev->dev.of_node);
+ dma_async_device_unregister(&zdev->common);
+
+ zynqmp_dma_chan_remove(zdev->chan);
+
+ return 0;
+}
+
+static const struct of_device_id zynqmp_dma_of_match[] = {
+ { .compatible = "xlnx,zynqmp-dma-1.0", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, zynqmp_dma_of_match);
+
+static struct platform_driver zynqmp_dma_driver = {
+ .driver = {
+ .name = "xilinx-zynqmp-dma",
+ .of_match_table = zynqmp_dma_of_match,
+ },
+ .probe = zynqmp_dma_probe,
+ .remove = zynqmp_dma_remove,
+};
+
+module_platform_driver(zynqmp_dma_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("Xilinx ZynqMP DMA driver");
+MODULE_LICENSE("GPL");
--
2.1.2