[PATCH 2/4] dmaengine: Add Oxford Semiconductor OXNAS DMA Controller
Neil Armstrong
narmstrong at baylibre.com
Tue Jan 4 06:52:04 PST 2022
The Oxford Semiconductor OX810SE contains a DMA engine mainly used
for the SATA controller which doesn't have an embedded DMA engine.
This DMA engine support single and scatter-gather memory-to-memory
transfers and device-to-memory/memory-to-device transfers.
Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
---
drivers/dma/Kconfig | 8 +
drivers/dma/Makefile | 1 +
drivers/dma/oxnas_adma.c | 1045 ++++++++++++++++++++++++++++++++++++++
3 files changed, 1054 insertions(+)
create mode 100644 drivers/dma/oxnas_adma.c
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 6bcdb4e6a0d1..8925ffd85ac2 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -505,6 +505,14 @@ config OWL_DMA
help
Enable support for the Actions Semi Owl SoCs DMA controller.
+config OXNAS_DMA
+ bool "Oxford Semiconductor OXNAS SoC Family DMA support"
+ select DMA_ENGINE
+ select DMA_VIRTUAL_CHANNELS
+ depends on ARCH_OXNAS || COMPILE_TEST
+ help
+ Support for Oxford Semiconductor OXNAS SoC Family DMA engine
+
config PCH_DMA
tristate "Intel EG20T PCH / LAPIS Semicon IOH(ML7213/ML7223/ML7831) DMA"
depends on PCI && (X86_32 || COMPILE_TEST)
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 616d926cf2a5..ba1111785bb8 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_MXS_DMA) += mxs-dma.o
obj-$(CONFIG_MX3_IPU) += ipu/
obj-$(CONFIG_NBPFAXI_DMA) += nbpfaxi.o
obj-$(CONFIG_OWL_DMA) += owl-dma.o
+obj-$(CONFIG_OXNAS_DMA) += oxnas_adma.o
obj-$(CONFIG_PCH_DMA) += pch_dma.o
obj-$(CONFIG_PL330_DMA) += pl330.o
obj-$(CONFIG_PLX_DMA) += plx_dma.o
diff --git a/drivers/dma/oxnas_adma.c b/drivers/dma/oxnas_adma.c
new file mode 100644
index 000000000000..586c23187de1
--- /dev/null
+++ b/drivers/dma/oxnas_adma.c
@@ -0,0 +1,1045 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Neil Armstrong <narmstrong at baylibre.com>
+ * Copyright (C) 2008 Oxford Semiconductor Ltd
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/semaphore.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/memory.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_dma.h>
+#include <linux/reset.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/bitfield.h>
+#include <linux/dma-mapping.h>
+
+#include "dmaengine.h"
+#include "virt-dma.h"
+
+/* Normal (non-SG) registers */
+#define DMA_REGS_PER_CHANNEL 8
+
+#define DMA_CTRL_STATUS 0x00
+#define DMA_BASE_SRC_ADR 0x04
+#define DMA_BASE_DST_ADR 0x08
+#define DMA_BYTE_CNT 0x0c
+#define DMA_CURRENT_SRC_ADR 0x10
+#define DMA_CURRENT_DST_ADR 0x14
+#define DMA_CURRENT_BYTE_CNT 0x18
+#define DMA_INTR_ID 0x1c
+#define DMA_INTR_CLEAR_REG (DMA_CURRENT_SRC_ADR)
+
+/* 8 quad-sized registers per channel arranged contiguously */
+#define DMA_CALC_REG_ADR(channel, register) (((channel) << 5) + (register))
+
+#define DMA_CTRL_STATUS_FAIR_SHARE_ARB BIT(0)
+#define DMA_CTRL_STATUS_IN_PROGRESS BIT(1)
+#define DMA_CTRL_STATUS_SRC_DREQ GENMASK(5, 2)
+#define DMA_CTRL_STATUS_DEST_DREQ GENMASK(10, 7)
+#define DMA_CTRL_STATUS_INTR BIT(10)
+#define DMA_CTRL_STATUS_NXT_FREE BIT(11)
+#define DMA_CTRL_STATUS_RESET BIT(12)
+#define DMA_CTRL_STATUS_DIR GENMASK(14, 13)
+#define DMA_CTRL_STATUS_SRC_ADR_MODE BIT(15)
+#define DMA_CTRL_STATUS_DEST_ADR_MODE BIT(16)
+#define DMA_CTRL_STATUS_TRANSFER_MODE_A BIT(17)
+#define DMA_CTRL_STATUS_TRANSFER_MODE_B BIT(18)
+#define DMA_CTRL_STATUS_SRC_WIDTH GENMASK(21, 19)
+#define DMA_CTRL_STATUS_DEST_WIDTH GENMASK(24, 22)
+#define DMA_CTRL_STATUS_PAUSE BIT(25)
+#define DMA_CTRL_STATUS_INTERRUPT_ENABLE BIT(26)
+#define DMA_CTRL_STATUS_SOURCE_ADDRESS_FIXED BIT(27)
+#define DMA_CTRL_STATUS_DESTINATION_ADDRESS_FIXED BIT(28)
+#define DMA_CTRL_STATUS_STARVE_LOW_PRIORITY BIT(29)
+#define DMA_CTRL_STATUS_INTR_CLEAR_ENABLE BIT(30)
+
+#define DMA_BYTE_CNT_MASK GENMASK(20, 0)
+#define DMA_BYTE_CNT_INC4_SET_MASK BIT(28)
+#define DMA_BYTE_CNT_HPROT_MASK BIT(29)
+#define DMA_BYTE_CNT_WR_EOT_MASK BIT(30)
+#define DMA_BYTE_CNT_RD_EOT_MASK BIT(31)
+
+#define DMA_INTR_ID_GET_NUM_CHANNELS(reg_contents) (((reg_contents) >> 16) & 0xFF)
+#define DMA_INTR_ID_GET_VERSION(reg_contents) (((reg_contents) >> 24) & 0xFF)
+#define DMA_INTR_ID_INT_MASK GENMASK(MAX_OXNAS_DMA_CHANNELS, 0)
+
+#define DMA_HAS_V4_INTR_CLEAR(version) ((version) > 3)
+
+/* H/W scatter gather controller registers */
+#define OXNAS_DMA_NUM_SG_REGS 4
+
+#define DMA_SG_CONTROL 0x00
+#define DMA_SG_STATUS 0x04
+#define DMA_SG_REQ_PTR 0x08
+#define DMA_SG_RESETS 0x0c
+
+#define DMA_SG_CALC_REG_ADR(channel, register) (((channel) << 4) + (register))
+
+/* SG DMA controller control register field definitions */
+#define DMA_SG_CONTROL_START BIT(0)
+#define DMA_SG_CONTROL_QUEUING_ENABLE BIT(1)
+#define DMA_SG_CONTROL_HBURST_ENABLE BIT(2)
+
+/* SG DMA controller status register field definitions */
+#define DMA_SG_STATUS_ERROR_CODE GENMASK(5, 0)
+#define DMA_SG_STATUS_BUSY BIT(7)
+
+/* SG DMA controller sub-block resets register field definitions */
+#define DMA_SG_RESETS_CONTROL BIT(0)
+#define DMA_SG_RESETS_ARBITER BIT(1)
+#define DMA_SG_RESETS_AHB BIT(2)
+
+/* SG DMA controller qualifier field definitions */
+#define OXNAS_DMA_SG_QUALIFIER GENMASK(15, 0)
+#define OXNAS_DMA_SG_DST_EOT GENMASK(17, 16)
+#define OXNAS_DMA_SG_SRC_EOT GENMASK(22, 20)
+#define OXNAS_DMA_SG_CHANNEL GENMASK(31, 24)
+
+#define OXNAS_DMA_ADR_MASK GENMASK(29, 0)
+#define OXNAS_DMA_MAX_TRANSFER_LENGTH DMA_BYTE_CNT_MASK
+
+/* The available buses to which the DMA controller is attached */
+enum {
+ OXNAS_DMA_SIDE_A = 0,
+ OXNAS_DMA_SIDE_B
+};
+
+/* Direction of data flow between the DMA controller's pair of interfaces */
+enum {
+ OXNAS_DMA_A_TO_A = 0,
+ OXNAS_DMA_B_TO_A,
+ OXNAS_DMA_A_TO_B,
+ OXNAS_DMA_B_TO_B
+};
+
+/* The available data widths */
+enum {
+ OXNAS_DMA_TRANSFER_WIDTH_8BITS = 0,
+ OXNAS_DMA_TRANSFER_WIDTH_16BITS,
+ OXNAS_DMA_TRANSFER_WIDTH_32BITS
+};
+
+/* The mode of the DMA transfer */
+enum {
+ OXNAS_DMA_TRANSFER_MODE_SINGLE = 0,
+ OXNAS_DMA_TRANSFER_MODE_BURST
+};
+
+/* The available transfer targets */
+enum {
+ OXNAS_DMA_DREQ_PATA = 0,
+ OXNAS_DMA_DREQ_SATA = 0,
+ OXNAS_DMA_DREQ_DPE_RX = 1,
+ OXNAS_DMA_DREQ_DPE_TX = 2,
+ OXNAS_DMA_DREQ_AUDIO_TX = 5,
+ OXNAS_DMA_DREQ_AUDIO_RX = 6,
+ OXNAS_DMA_DREQ_MEMORY = 15
+};
+
+enum {
+ OXNAS_DMA_TYPE_SIMPLE = 0,
+ OXNAS_DMA_TYPE_SG,
+};
+
+#define MAX_OXNAS_DMA_CHANNELS 5
+#define MAX_OXNAS_SG_ENTRIES 512
+
+/* Will be exchanged with SG DMA controller */
+struct oxnas_dma_sg_entry {
+ dma_addr_t data_addr; /* physical address of the buffer */
+ unsigned long data_length; /* length of the buffer */
+ dma_addr_t p_next_entry; /* physical address of next descriptor */
+ struct oxnas_dma_sg_entry *next_entry; /* virtual address of the next descriptor */
+ dma_addr_t this_paddr; /* physical address of this descriptor */
+ struct list_head entry; /* Linked list entry */
+} __attribute((aligned(4), packed));
+
+/* Will be exchanged with SG DMA controller */
+struct oxnas_dma_sg_info {
+ unsigned long qualifier;
+ unsigned long control;
+ dma_addr_t p_src_entries; /* physical address of the first source SG desc */
+ dma_addr_t p_dst_entries; /* physical address of the first dest SG desc */
+ struct oxnas_dma_sg_entry *src_entries; /* virtual address of the first source SG desc */
+ struct oxnas_dma_sg_entry *dst_entries; /* virtual address of the first dest SG desc */
+} __attribute((aligned(4), packed));
+
+struct oxnas_dma_sg_data {
+ struct oxnas_dma_sg_entry entries[MAX_OXNAS_SG_ENTRIES];
+ struct oxnas_dma_sg_info infos[MAX_OXNAS_DMA_CHANNELS];
+} __attribute((aligned(4)));
+
+struct oxnas_dma_device;
+struct oxnas_dma_channel;
+
+struct oxnas_dma_desc {
+ struct virt_dma_desc vd;
+ struct oxnas_dma_channel *channel;
+ unsigned long ctrl;
+ unsigned long len;
+ dma_addr_t src_adr;
+ dma_addr_t dst_adr;
+ unsigned int type;
+ struct oxnas_dma_sg_info sg_info;
+ unsigned int entries;
+ struct list_head sg_entries;
+};
+
+struct oxnas_dma_channel {
+ struct virt_dma_chan vc;
+ struct list_head node;
+ struct oxnas_dma_device *dmadev;
+ unsigned int id;
+ unsigned int irq;
+
+ struct dma_slave_config cfg;
+
+ dma_addr_t p_sg_info; /* physical address of the array of sg_info structs */
+ struct oxnas_dma_sg_info *sg_info; /* virtual address of the array of sg_info structs */
+
+ atomic_t active;
+
+ struct oxnas_dma_desc *cur;
+};
+
+struct oxnas_dma_device {
+ struct platform_device *pdev;
+ struct dma_device common;
+ void __iomem *dma_base;
+ void __iomem *sgdma_base;
+ struct reset_control *dma_rst;
+ struct reset_control *sgdma_rst;
+ struct clk *dma_clk;
+
+ unsigned int channels_count;
+
+ struct oxnas_dma_channel channels[MAX_OXNAS_DMA_CHANNELS];
+
+ unsigned int hwversion;
+
+ /* Protects concurrent access to channels */
+ spinlock_t lock;
+ struct tasklet_struct tasklet;
+
+ struct list_head pending;
+
+ struct {
+ dma_addr_t start;
+ dma_addr_t end;
+ unsigned int type;
+ } *authorized_types;
+ unsigned int authorized_types_count;
+
+ struct list_head free_entries;
+ atomic_t free_entries_count;
+ dma_addr_t p_sg_data;
+ struct oxnas_dma_sg_data *sg_data;
+};
+
+static void oxnas_dma_start_next(struct oxnas_dma_channel *channel);
+
+static irqreturn_t oxnas_dma_interrupt(int irq, void *dev_id)
+{
+ struct oxnas_dma_channel *channel = dev_id;
+ struct oxnas_dma_device *dmadev = channel->dmadev;
+ unsigned long error_code;
+ unsigned long flags;
+
+ dev_vdbg(&dmadev->pdev->dev, "irq for channel %d\n", channel->id);
+
+ while (readl(dmadev->dma_base + DMA_CALC_REG_ADR(0, DMA_INTR_ID)) & BIT(channel->id)) {
+ dev_dbg(&dmadev->pdev->dev, "Acking interrupt for channel %u\n",
+ channel->id);
+
+ /* Write to the interrupt clear register to clear interrupt */
+ writel(0, dmadev->dma_base + DMA_CALC_REG_ADR(channel->id, DMA_INTR_CLEAR_REG));
+ }
+
+ if (channel->cur && channel->cur->type == OXNAS_DMA_TYPE_SG) {
+ error_code = readl(dmadev->sgdma_base +
+ DMA_SG_CALC_REG_ADR(channel->id, DMA_SG_STATUS));
+ error_code &= DMA_SG_STATUS_ERROR_CODE;
+
+ /* TOFIX report it to the core */
+ if (error_code)
+ dev_err(&dmadev->pdev->dev, "ch%d: sgdma err %x\n",
+ channel->id, (unsigned int)error_code);
+
+ writel(1, dmadev->sgdma_base + DMA_SG_CALC_REG_ADR(channel->id, DMA_SG_STATUS));
+ }
+
+ spin_lock_irqsave(&channel->vc.lock, flags);
+
+ if (atomic_read(&channel->active)) {
+ struct oxnas_dma_desc *cur = channel->cur;
+
+ oxnas_dma_start_next(channel);
+ if (cur)
+ vchan_cookie_complete(&cur->vd);
+ } else {
+ dev_warn(&dmadev->pdev->dev, "spurious irq for channel %d\n",
+ channel->id);
+ }
+
+ spin_unlock_irqrestore(&channel->vc.lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static void oxnas_dma_start_next(struct oxnas_dma_channel *channel)
+{
+ struct oxnas_dma_device *dmadev = channel->dmadev;
+ struct virt_dma_desc *vd = vchan_next_desc(&channel->vc);
+ struct oxnas_dma_desc *desc;
+ unsigned long ctrl_status;
+
+ if (!vd) {
+ channel->cur = NULL;
+ return;
+ }
+
+ list_del(&vd->node);
+
+ desc = container_of(&vd->tx, struct oxnas_dma_desc, vd.tx);
+ channel->cur = desc;
+
+ if (desc->type == OXNAS_DMA_TYPE_SIMPLE) {
+ /* Write the control/status value to the DMAC */
+ writel(desc->ctrl,
+ dmadev->dma_base + DMA_CALC_REG_ADR(channel->id, DMA_CTRL_STATUS));
+
+ /* Ensure control/status word makes it to the DMAC before
+ * we write address/length info
+ */
+ wmb();
+
+ /* Write the source addresses to the DMAC */
+ writel(desc->src_adr & OXNAS_DMA_ADR_MASK,
+ dmadev->dma_base + DMA_CALC_REG_ADR(channel->id, DMA_BASE_SRC_ADR));
+
+ /* Write the destination addresses to the DMAC */
+ writel(desc->dst_adr & OXNAS_DMA_ADR_MASK,
+ dmadev->dma_base + DMA_CALC_REG_ADR(channel->id, DMA_BASE_DST_ADR));
+
+ /* Write the length, with EOT configuration
+ * for the single transfer
+ */
+ writel(desc->len,
+ dmadev->dma_base + DMA_CALC_REG_ADR(channel->id, DMA_BYTE_CNT));
+
+ /* Ensure adr/len info makes it to DMAC before later modifications to
+ * control/status register due to starting the transfer, which happens in
+ * oxnas_dma_start()
+ */
+ wmb();
+
+ /* Setup channel data */
+ atomic_set(&channel->active, 1);
+
+ /* Single transfer mode, so unpause the DMA controller channel */
+ ctrl_status = readl(dmadev->dma_base +
+ DMA_CALC_REG_ADR(channel->id, DMA_CTRL_STATUS));
+ writel(ctrl_status & ~DMA_CTRL_STATUS_PAUSE,
+ dmadev->dma_base + DMA_CALC_REG_ADR(channel->id, DMA_CTRL_STATUS));
+
+ dev_dbg(&dmadev->pdev->dev, "ch%d: started req %d from %08x to %08x, %lubytes\n",
+ channel->id, vd->tx.cookie,
+ desc->src_adr, desc->dst_adr,
+ desc->len & OXNAS_DMA_MAX_TRANSFER_LENGTH);
+ } else if (desc->type == OXNAS_DMA_TYPE_SG) {
+ /* Write to the SG-DMA channel's reset register to reset the control
+ * in case the previous SG-DMA transfer failed in some way, thus
+ * leaving the SG-DMA controller hung up part way through processing
+ * its SG list. The reset bits are self-clearing
+ */
+ writel(DMA_SG_RESETS_CONTROL,
+ dmadev->sgdma_base + DMA_SG_CALC_REG_ADR(channel->id, DMA_SG_RESETS));
+
+ /* Copy the sg_info structure */
+ memcpy(channel->sg_info, &desc->sg_info, sizeof(struct oxnas_dma_sg_info));
+
+ /* Ensure adr/len info makes it to DMAC before later modifications to
+ * control/status register due to starting the transfer, which happens in
+ * oxnas_dma_start()
+ */
+ wmb();
+
+ /* Write the pointer to the SG info struct into the Request Pointer reg */
+ writel(channel->p_sg_info,
+ dmadev->sgdma_base + DMA_SG_CALC_REG_ADR(channel->id, DMA_SG_REQ_PTR));
+
+ /* Setup channel data */
+ atomic_set(&channel->active, 1);
+
+ /* Start the transfert */
+ writel(DMA_SG_CONTROL_START |
+ DMA_SG_CONTROL_QUEUING_ENABLE |
+ DMA_SG_CONTROL_HBURST_ENABLE,
+ dmadev->sgdma_base + DMA_SG_CALC_REG_ADR(channel->id, DMA_SG_CONTROL));
+
+ dev_dbg(&dmadev->pdev->dev, "ch%d: started %d sg req with %d entries\n",
+ channel->id, vd->tx.cookie,
+ desc->entries);
+ }
+}
+
+static void oxnas_dma_sched(unsigned long data)
+{
+ struct oxnas_dma_device *dmadev = (struct oxnas_dma_device *)data;
+ LIST_HEAD(head);
+
+ spin_lock_irq(&dmadev->lock);
+ list_splice_tail_init(&dmadev->pending, &head);
+ spin_unlock_irq(&dmadev->lock);
+
+ while (!list_empty(&head)) {
+ struct oxnas_dma_channel *ch = list_first_entry(&head,
+ struct oxnas_dma_channel, node);
+
+ spin_lock_irq(&ch->vc.lock);
+
+ list_del_init(&ch->node);
+ oxnas_dma_start_next(ch);
+
+ spin_unlock_irq(&ch->vc.lock);
+ }
+}
+
+static int oxnas_check_address(struct oxnas_dma_device *dmadev, dma_addr_t address)
+{
+ int i;
+
+ for (i = 0 ; i < dmadev->authorized_types_count ; ++i) {
+ if (address >= dmadev->authorized_types[i].start &&
+ address < dmadev->authorized_types[i].end)
+ return dmadev->authorized_types[i].type;
+ }
+
+ return -1;
+}
+
+static struct dma_async_tx_descriptor *oxnas_dma_prep_slave_sg(struct dma_chan *chan,
+ struct scatterlist *sgl,
+ unsigned int sglen,
+ enum dma_transfer_direction dir,
+ unsigned long flags, void *context)
+{
+ struct oxnas_dma_channel *channel = container_of(chan, struct oxnas_dma_channel, vc.chan);
+ struct oxnas_dma_device *dmadev = channel->dmadev;
+ struct oxnas_dma_desc *desc;
+ struct scatterlist *sgent;
+ struct oxnas_dma_sg_entry *entry_mem = NULL, *prev_entry_mem = NULL;
+ struct oxnas_dma_sg_entry *entry_dev = NULL;
+ unsigned int i;
+ int src_memory = OXNAS_DMA_DREQ_MEMORY;
+ int dst_memory = OXNAS_DMA_DREQ_MEMORY;
+
+ if (dir == DMA_DEV_TO_MEM) {
+ src_memory = oxnas_check_address(dmadev, channel->cfg.src_addr);
+ if (src_memory == -1) {
+ dev_err(&dmadev->pdev->dev, "invalid memory address %08x\n",
+ channel->cfg.src_addr);
+ return NULL;
+ }
+
+ if (src_memory == OXNAS_DMA_DREQ_MEMORY) {
+ dev_err(&dmadev->pdev->dev, "In DEV_TO_MEM, src cannot be memory\n");
+ return NULL;
+ }
+ } else if (dir == DMA_MEM_TO_DEV) {
+ dst_memory = oxnas_check_address(dmadev, channel->cfg.dst_addr);
+ if (dst_memory == -1) {
+ dev_err(&dmadev->pdev->dev, "invalid memory address %08x\n",
+ channel->cfg.dst_addr);
+ return NULL;
+ }
+
+ if (dst_memory == OXNAS_DMA_DREQ_MEMORY) {
+ dev_err(&dmadev->pdev->dev, "In MEM_TO_DEV, dst cannot be memory\n");
+ return NULL;
+ }
+ } else {
+ dev_err(&dmadev->pdev->dev, "invalid direction\n");
+ return NULL;
+ }
+
+ if (atomic_read(&dmadev->free_entries_count) < (sglen + 1)) {
+ dev_err(&dmadev->pdev->dev, "Missing sg entries...\n");
+ return NULL;
+ }
+
+ desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+ if (unlikely(!desc))
+ return NULL;
+ desc->channel = channel;
+
+ INIT_LIST_HEAD(&desc->sg_entries);
+ desc->entries = 0;
+
+ /* Device single entry */
+ entry_dev = list_first_entry_or_null(&dmadev->free_entries,
+ struct oxnas_dma_sg_entry, entry);
+ if (!entry_dev) {
+ dev_err(&dmadev->pdev->dev, "Fatal error: Missing dev sg entry...\n");
+ goto entries_cleanup;
+ }
+
+ atomic_dec(&dmadev->free_entries_count);
+ list_move(&entry_dev->entry, &desc->sg_entries);
+ ++desc->entries;
+ dev_dbg(&dmadev->pdev->dev, "got entry %p (%08x)\n", entry_dev, entry_dev->this_paddr);
+
+ entry_dev->next_entry = NULL;
+ entry_dev->p_next_entry = 0;
+ entry_dev->data_length = 0; /* Completed by mem sg entries */
+
+ if (dir == DMA_DEV_TO_MEM) {
+ entry_dev->data_addr = channel->cfg.src_addr & OXNAS_DMA_ADR_MASK;
+ desc->sg_info.src_entries = entry_dev;
+ desc->sg_info.p_src_entries = entry_dev->this_paddr;
+
+ dev_dbg(&dmadev->pdev->dev, "src set %p\n", entry_dev);
+ } else if (dir == DMA_MEM_TO_DEV) {
+ entry_dev->data_addr = channel->cfg.dst_addr & OXNAS_DMA_ADR_MASK;
+ desc->sg_info.dst_entries = entry_dev;
+ desc->sg_info.p_dst_entries = entry_dev->this_paddr;
+
+ dev_dbg(&dmadev->pdev->dev, "dst set %p\n", entry_dev);
+ }
+
+ dev_dbg(&dmadev->pdev->dev, "src = %p (%08x) dst = %p (%08x)\n",
+ desc->sg_info.src_entries, desc->sg_info.p_src_entries,
+ desc->sg_info.dst_entries, desc->sg_info.p_dst_entries);
+
+ /* Memory entries */
+ for_each_sg(sgl, sgent, sglen, i) {
+ entry_mem = list_first_entry_or_null(&dmadev->free_entries,
+ struct oxnas_dma_sg_entry, entry);
+ if (!entry_mem) {
+ dev_err(&dmadev->pdev->dev, "Fatal error: Missing mem sg entries...\n");
+ goto entries_cleanup;
+ }
+
+ atomic_dec(&dmadev->free_entries_count);
+ list_move(&entry_mem->entry, &desc->sg_entries);
+ ++desc->entries;
+ dev_dbg(&dmadev->pdev->dev, "got entry %p (%08x)\n",
+ entry_mem, entry_mem->this_paddr);
+
+ /* Fill the linked list */
+ if (prev_entry_mem) {
+ prev_entry_mem->next_entry = entry_mem;
+ prev_entry_mem->p_next_entry = entry_mem->this_paddr;
+ } else {
+ if (dir == DMA_DEV_TO_MEM) {
+ desc->sg_info.dst_entries = entry_mem;
+ desc->sg_info.p_dst_entries = entry_mem->this_paddr;
+ dev_dbg(&dmadev->pdev->dev, "src set %p\n", entry_mem);
+ } else if (dir == DMA_MEM_TO_DEV) {
+ desc->sg_info.src_entries = entry_mem;
+ desc->sg_info.p_src_entries = entry_mem->this_paddr;
+ dev_dbg(&dmadev->pdev->dev, "dst set %p\n", entry_mem);
+ }
+
+ dev_dbg(&dmadev->pdev->dev, "src = %p (%08x) dst = %p (%08x)\n",
+ desc->sg_info.src_entries, desc->sg_info.p_src_entries,
+ desc->sg_info.dst_entries, desc->sg_info.p_dst_entries);
+ }
+ prev_entry_mem = entry_mem;
+
+ /* Fill the entry from the SG */
+ entry_mem->next_entry = NULL;
+ entry_mem->p_next_entry = 0;
+
+ entry_mem->data_addr = sg_dma_address(sgent) & OXNAS_DMA_ADR_MASK;
+ entry_mem->data_length = sg_dma_len(sgent);
+ dev_dbg(&dmadev->pdev->dev, "sg = %08x len = %d\n",
+ sg_dma_address(sgent), sg_dma_len(sgent));
+
+ /* Add to dev sg length */
+ entry_dev->data_length += sg_dma_len(sgent);
+ }
+ dev_dbg(&dmadev->pdev->dev, "allocated %d sg entries\n", desc->entries);
+
+ desc->sg_info.qualifier = FIELD_PREP(OXNAS_DMA_SG_CHANNEL, channel->id) |
+ OXNAS_DMA_SG_QUALIFIER;
+
+ if (dir == DMA_DEV_TO_MEM)
+ desc->sg_info.qualifier |= FIELD_PREP(OXNAS_DMA_SG_SRC_EOT, 2);
+ else if (dir == DMA_MEM_TO_DEV)
+ desc->sg_info.qualifier |= FIELD_PREP(OXNAS_DMA_SG_DST_EOT, 2);
+
+ desc->sg_info.control = (DMA_CTRL_STATUS_INTERRUPT_ENABLE |
+ DMA_CTRL_STATUS_FAIR_SHARE_ARB |
+ DMA_CTRL_STATUS_INTR_CLEAR_ENABLE);
+ desc->sg_info.control |= FIELD_PREP(DMA_CTRL_STATUS_SRC_DREQ, src_memory);
+ desc->sg_info.control |= FIELD_PREP(DMA_CTRL_STATUS_DEST_DREQ, dst_memory);
+
+ if (dir == DMA_DEV_TO_MEM) {
+ desc->sg_info.control |= DMA_CTRL_STATUS_SRC_ADR_MODE;
+ desc->sg_info.control &= ~DMA_CTRL_STATUS_SOURCE_ADDRESS_FIXED;
+ desc->sg_info.control |= DMA_CTRL_STATUS_DEST_ADR_MODE;
+ desc->sg_info.control &= ~DMA_CTRL_STATUS_DESTINATION_ADDRESS_FIXED;
+ } else if (dir == DMA_MEM_TO_DEV) {
+ desc->sg_info.control |= DMA_CTRL_STATUS_SRC_ADR_MODE;
+ desc->sg_info.control &= ~DMA_CTRL_STATUS_SOURCE_ADDRESS_FIXED;
+ desc->sg_info.control |= DMA_CTRL_STATUS_DEST_ADR_MODE;
+ desc->sg_info.control &= ~DMA_CTRL_STATUS_DESTINATION_ADDRESS_FIXED;
+ }
+ desc->sg_info.control |= DMA_CTRL_STATUS_TRANSFER_MODE_A;
+ desc->sg_info.control |= DMA_CTRL_STATUS_TRANSFER_MODE_B;
+ desc->sg_info.control |= FIELD_PREP(DMA_CTRL_STATUS_DIR, OXNAS_DMA_A_TO_B);
+
+ desc->sg_info.control |= FIELD_PREP(DMA_CTRL_STATUS_SRC_WIDTH,
+ OXNAS_DMA_TRANSFER_WIDTH_32BITS);
+ desc->sg_info.control |= FIELD_PREP(DMA_CTRL_STATUS_DEST_WIDTH,
+ OXNAS_DMA_TRANSFER_WIDTH_32BITS);
+ desc->sg_info.control &= ~DMA_CTRL_STATUS_STARVE_LOW_PRIORITY;
+
+ desc->type = OXNAS_DMA_TYPE_SG;
+
+ return vchan_tx_prep(&channel->vc, &desc->vd, flags);
+
+entries_cleanup:
+ /* Put back all entries in the free entries... */
+ list_splice_tail_init(&desc->sg_entries, &dmadev->free_entries);
+ atomic_add(desc->entries, &dmadev->free_entries_count);
+ dev_dbg(&dmadev->pdev->dev, "freed %d sg entries\n", desc->entries);
+
+ kfree(desc);
+
+ return NULL;
+}
+
+/** Allocate descriptors capable of mapping the requested length of memory */
+static struct dma_async_tx_descriptor *oxnas_dma_prep_dma_memcpy(struct dma_chan *chan,
+ dma_addr_t dst, dma_addr_t src,
+ size_t len, unsigned long flags)
+{
+ struct oxnas_dma_channel *channel = container_of(chan, struct oxnas_dma_channel, vc.chan);
+ struct oxnas_dma_device *dmadev = channel->dmadev;
+ struct oxnas_dma_desc *desc;
+ int src_memory = OXNAS_DMA_DREQ_MEMORY;
+ int dst_memory = OXNAS_DMA_DREQ_MEMORY;
+
+ if (len > OXNAS_DMA_MAX_TRANSFER_LENGTH)
+ return NULL;
+
+ src_memory = oxnas_check_address(dmadev, src);
+ if (src_memory == -1) {
+ dev_err(&dmadev->pdev->dev, "invalid memory address %08x\n", src);
+ return NULL;
+ }
+
+ dst_memory = oxnas_check_address(dmadev, dst);
+ if (dst_memory == -1) {
+ dev_err(&dmadev->pdev->dev, "invalid memory address %08x\n", src);
+ return NULL;
+ }
+
+ desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+ if (unlikely(!desc))
+ return NULL;
+ desc->channel = channel;
+
+ dev_dbg(&dmadev->pdev->dev, "preparing memcpy from %08x to %08x, %lubytes (flags %x)\n",
+ src, dst, (unsigned long)len, (unsigned int)flags);
+
+ /* CTRL STATUS Preparation */
+
+ /* Pause while start */
+ desc->ctrl = DMA_CTRL_STATUS_PAUSE;
+
+ /* Interrupts enabled
+ * High priority
+ * Use new interrupt clearing register
+ */
+ desc->ctrl |= DMA_CTRL_STATUS_INTERRUPT_ENABLE |
+ DMA_CTRL_STATUS_FAIR_SHARE_ARB |
+ DMA_CTRL_STATUS_INTR_CLEAR_ENABLE;
+
+ /* Type Memory */
+ desc->ctrl |= FIELD_PREP(DMA_CTRL_STATUS_SRC_DREQ, src_memory);
+ desc->ctrl |= FIELD_PREP(DMA_CTRL_STATUS_DEST_DREQ, dst_memory);
+
+ /* Setup the transfer direction and burst/single mode for the two DMA busses */
+ desc->ctrl |= DMA_CTRL_STATUS_TRANSFER_MODE_A;
+ desc->ctrl |= DMA_CTRL_STATUS_TRANSFER_MODE_B;
+ desc->ctrl |= FIELD_PREP(DMA_CTRL_STATUS_DIR, OXNAS_DMA_A_TO_B);
+
+ /* Incrementing addresses */
+ desc->ctrl |= DMA_CTRL_STATUS_SRC_ADR_MODE;
+ desc->ctrl &= ~DMA_CTRL_STATUS_SOURCE_ADDRESS_FIXED;
+ desc->ctrl |= DMA_CTRL_STATUS_DEST_ADR_MODE;
+ desc->ctrl &= ~DMA_CTRL_STATUS_DESTINATION_ADDRESS_FIXED;
+
+ /* Set up the width of the transfers on the DMA buses */
+ desc->ctrl |= FIELD_PREP(DMA_CTRL_STATUS_SRC_WIDTH, OXNAS_DMA_TRANSFER_WIDTH_32BITS);
+ desc->ctrl |= FIELD_PREP(DMA_CTRL_STATUS_DEST_WIDTH, OXNAS_DMA_TRANSFER_WIDTH_32BITS);
+
+ /* Setup the priority arbitration scheme */
+ desc->ctrl &= ~DMA_CTRL_STATUS_STARVE_LOW_PRIORITY;
+
+ /* LENGTH and End Of Transfert Preparation */
+ desc->len = len |
+ DMA_BYTE_CNT_INC4_SET_MASK | /* Always enable INC4 transfers */
+ DMA_BYTE_CNT_HPROT_MASK | /* Always enable HPROT assertion */
+ DMA_BYTE_CNT_RD_EOT_MASK; /* EOT at last Read */
+
+ desc->src_adr = src;
+ desc->dst_adr = dst;
+ desc->type = OXNAS_DMA_TYPE_SIMPLE;
+
+ return vchan_tx_prep(&channel->vc, &desc->vd, flags);
+}
+
+static int oxnas_dma_slave_config(struct dma_chan *chan, struct dma_slave_config *cfg)
+{
+ struct oxnas_dma_channel *channel = container_of(chan, struct oxnas_dma_channel, vc.chan);
+
+ memcpy(&channel->cfg, cfg, sizeof(channel->cfg));
+
+ return 0;
+}
+
+static void oxnas_dma_desc_free(struct virt_dma_desc *vd)
+{
+ struct oxnas_dma_desc *desc = container_of(&vd->tx, struct oxnas_dma_desc, vd.tx);
+ struct oxnas_dma_channel *channel = desc->channel;
+ struct oxnas_dma_device *dmadev = channel->dmadev;
+
+ /* Free SG entries */
+ if (desc->type == OXNAS_DMA_TYPE_SG) {
+ list_splice_tail_init(&desc->sg_entries, &dmadev->free_entries);
+ atomic_add(desc->entries, &dmadev->free_entries_count);
+ dev_dbg(&dmadev->pdev->dev, "freed %d sg entries\n", desc->entries);
+ }
+
+ kfree(container_of(vd, struct oxnas_dma_desc, vd));
+}
+
+/** Poll for the DMA channel's active status. There can be multiple transfers
+ * queued with the DMA channel identified by cookies, so should be checking
+ * lists containing all pending transfers and all completed transfers that have
+ * not yet been polled for completion
+ */
+static enum dma_status oxnas_dma_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct oxnas_dma_channel *channel = container_of(chan, struct oxnas_dma_channel, vc.chan);
+ struct virt_dma_desc *vd;
+ enum dma_status ret;
+ unsigned long flags;
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ if (ret == DMA_COMPLETE || !txstate)
+ return ret;
+
+ spin_lock_irqsave(&channel->vc.lock, flags);
+ vd = vchan_find_desc(&channel->vc, cookie);
+ if (vd) {
+ struct oxnas_dma_desc *desc = container_of(&vd->tx, struct oxnas_dma_desc, vd.tx);
+
+ txstate->residue = desc->len & OXNAS_DMA_MAX_TRANSFER_LENGTH;
+ } else {
+ txstate->residue = 0;
+ }
+ spin_unlock_irqrestore(&channel->vc.lock, flags);
+
+ return ret;
+}
+
+/** To push outstanding transfers to h/w. This should use the list of pending
+ * transfers identified by cookies to select the next transfer and pass this to
+ * the hardware
+ */
+static void oxnas_dma_issue_pending(struct dma_chan *chan)
+{
+ struct oxnas_dma_channel *channel = container_of(chan, struct oxnas_dma_channel, vc.chan);
+ struct oxnas_dma_device *dmadev = channel->dmadev;
+ unsigned long flags;
+
+ spin_lock_irqsave(&channel->vc.lock, flags);
+ if (vchan_issue_pending(&channel->vc) && !channel->cur) {
+ spin_lock(&dmadev->lock);
+
+ if (list_empty(&channel->node))
+ list_add_tail(&channel->node, &dmadev->pending);
+
+ spin_unlock(&dmadev->lock);
+
+ tasklet_schedule(&dmadev->tasklet);
+ }
+
+ spin_unlock_irqrestore(&channel->vc.lock, flags);
+}
+
+static void oxnas_dma_free_chan_resources(struct dma_chan *chan)
+{
+ struct oxnas_dma_channel *channel = container_of(chan, struct oxnas_dma_channel, vc.chan);
+
+ vchan_free_chan_resources(&channel->vc);
+}
+
+static int oxnas_dma_probe(struct platform_device *pdev)
+{
+ struct oxnas_dma_device *dmadev;
+ struct resource *res;
+ int hwid, i, ret;
+
+ dmadev = devm_kzalloc(&pdev->dev, sizeof(struct oxnas_dma_device), GFP_KERNEL);
+ if (!dmadev)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ dmadev->dma_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(dmadev->dma_base))
+ return PTR_ERR(dmadev->dma_base);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ dmadev->sgdma_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(dmadev->sgdma_base))
+ return PTR_ERR(dmadev->sgdma_base);
+
+ dmadev->dma_rst = devm_reset_control_get(&pdev->dev, "dma");
+ if (IS_ERR(dmadev->dma_rst))
+ return PTR_ERR(dmadev->dma_rst);
+
+ dmadev->sgdma_rst = devm_reset_control_get(&pdev->dev, "sgdma");
+ if (IS_ERR(dmadev->sgdma_rst))
+ return PTR_ERR(dmadev->sgdma_rst);
+
+ dmadev->dma_clk = devm_clk_get(&pdev->dev, 0);
+ if (IS_ERR(dmadev->dma_clk))
+ return PTR_ERR(dmadev->dma_clk);
+
+ ret = of_property_count_elems_of_size(pdev->dev.of_node, "oxsemi,targets-types", 4);
+ if (ret <= 0 || (ret % 3) != 0) {
+ dev_err(&pdev->dev, "malformed or missing oxsemi,targets-types\n");
+ return -EINVAL;
+ }
+
+ dmadev->authorized_types_count = ret / 3;
+ dmadev->authorized_types = devm_kzalloc(&pdev->dev,
+ sizeof(*dmadev->authorized_types) * dmadev->authorized_types_count, GFP_KERNEL);
+
+ if (!dmadev->authorized_types)
+ return -ENOMEM;
+
+ for (i = 0 ; i < dmadev->authorized_types_count ; ++i) {
+ u32 value;
+
+ ret = of_property_read_u32_index(pdev->dev.of_node,
+ "oxsemi,targets-types",
+ (i * 3), &value);
+ if (ret < 0)
+ return ret;
+
+ dmadev->authorized_types[i].start = value;
+ ret = of_property_read_u32_index(pdev->dev.of_node,
+ "oxsemi,targets-types",
+ (i * 3) + 1, &value);
+ if (ret < 0)
+ return ret;
+
+ dmadev->authorized_types[i].end = value;
+ ret = of_property_read_u32_index(pdev->dev.of_node,
+ "oxsemi,targets-types",
+ (i * 3) + 2, &value);
+ if (ret < 0)
+ return ret;
+
+ dmadev->authorized_types[i].type = value;
+ }
+
+ dev_dbg(&pdev->dev, "Authorized memory ranges :\n");
+ dev_dbg(&pdev->dev, " Start - End = Type\n");
+ for (i = 0 ; i < dmadev->authorized_types_count ; ++i)
+ dev_dbg(&pdev->dev, "0x%08x-0x%08x = %d\n",
+ dmadev->authorized_types[i].start,
+ dmadev->authorized_types[i].end,
+ dmadev->authorized_types[i].type);
+
+ dmadev->pdev = pdev;
+
+ spin_lock_init(&dmadev->lock);
+
+ tasklet_init(&dmadev->tasklet, oxnas_dma_sched, (unsigned long)dmadev);
+ INIT_LIST_HEAD(&dmadev->common.channels);
+ INIT_LIST_HEAD(&dmadev->pending);
+ INIT_LIST_HEAD(&dmadev->free_entries);
+
+ /* Enable HW & Clocks */
+ reset_control_reset(dmadev->dma_rst);
+ reset_control_reset(dmadev->sgdma_rst);
+ clk_prepare_enable(dmadev->dma_clk);
+
+ /* Discover the number of channels available */
+ hwid = readl(dmadev->dma_base + DMA_CALC_REG_ADR(0, DMA_INTR_ID));
+ dmadev->channels_count = DMA_INTR_ID_GET_NUM_CHANNELS(hwid);
+ dmadev->hwversion = DMA_INTR_ID_GET_VERSION(hwid);
+
+ dev_dbg(&pdev->dev, "OXNAS DMA v%x with %d channels\n",
+ dmadev->hwversion, dmadev->channels_count);
+
+ /* Limit channels count */
+ if (dmadev->channels_count > MAX_OXNAS_DMA_CHANNELS)
+ dmadev->channels_count = MAX_OXNAS_DMA_CHANNELS;
+
+ /* Allocate coherent memory for sg descriptors */
+ dmadev->sg_data = dma_alloc_coherent(&pdev->dev, sizeof(struct oxnas_dma_sg_data),
+ &dmadev->p_sg_data, GFP_KERNEL);
+ if (!dmadev->sg_data) {
+ ret = -ENOMEM;
+ goto disable_clks;
+ }
+
+ /* Reset SG descritors */
+ memset(dmadev->sg_data, 0, sizeof(struct oxnas_dma_sg_data));
+ atomic_set(&dmadev->free_entries_count, 0);
+
+ /* Initialize and add all sg entries to the free list */
+ for (i = 0 ; i < MAX_OXNAS_SG_ENTRIES ; ++i) {
+ dmadev->sg_data->entries[i].this_paddr =
+ (dma_addr_t)&(((struct oxnas_dma_sg_data *)dmadev->p_sg_data)->entries[i]);
+ INIT_LIST_HEAD(&dmadev->sg_data->entries[i].entry);
+ list_add_tail(&dmadev->sg_data->entries[i].entry,
+ &dmadev->free_entries);
+ atomic_inc(&dmadev->free_entries_count);
+ }
+
+ /* Init all channels */
+ for (i = 0 ; i < dmadev->channels_count ; ++i) {
+ struct oxnas_dma_channel *ch = &dmadev->channels[i];
+
+ ch->dmadev = dmadev;
+ ch->id = i;
+
+ ch->irq = irq_of_parse_and_map(pdev->dev.of_node, i);
+ if (ch->irq <= 0) {
+ dev_err(&pdev->dev, "invalid irq%d from platform\n", i);
+ goto free_coherent;
+ }
+
+ ret = devm_request_irq(&pdev->dev, ch->irq,
+ oxnas_dma_interrupt, 0,
+ "DMA", ch);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to request irq%d\n", i);
+ goto free_coherent;
+ }
+
+ ch->p_sg_info =
+ (dma_addr_t)&((struct oxnas_dma_sg_data *)dmadev->p_sg_data)->infos[i];
+ ch->sg_info = &dmadev->sg_data->infos[i];
+ memset(ch->sg_info, 0, sizeof(struct oxnas_dma_sg_info));
+
+ atomic_set(&ch->active, 0);
+
+ ch->vc.desc_free = oxnas_dma_desc_free;
+ vchan_init(&ch->vc, &dmadev->common);
+ INIT_LIST_HEAD(&ch->node);
+ }
+
+ platform_set_drvdata(pdev, dmadev);
+
+ dma_cap_set(DMA_MEMCPY, dmadev->common.cap_mask);
+ dmadev->common.chancnt = dmadev->channels_count;
+ dmadev->common.device_free_chan_resources = oxnas_dma_free_chan_resources;
+ dmadev->common.device_tx_status = oxnas_dma_tx_status;
+ dmadev->common.device_issue_pending = oxnas_dma_issue_pending;
+ dmadev->common.device_prep_dma_memcpy = oxnas_dma_prep_dma_memcpy;
+ dmadev->common.device_prep_slave_sg = oxnas_dma_prep_slave_sg;
+ dmadev->common.device_config = oxnas_dma_slave_config;
+ dmadev->common.copy_align = DMAENGINE_ALIGN_4_BYTES;
+ dmadev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmadev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dmadev->common.directions = BIT(DMA_MEM_TO_MEM);
+ dmadev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+ dmadev->common.dev = &pdev->dev;
+
+ ret = dma_async_device_register(&dmadev->common);
+ if (ret)
+ goto free_coherent;
+
+ ret = of_dma_controller_register(pdev->dev.of_node,
+ of_dma_xlate_by_chan_id,
+ &dmadev->common);
+ if (ret) {
+ dev_warn(&pdev->dev, "Failed to register DMA Controller\n");
+ goto dma_unregister;
+ }
+
+ dev_info(&pdev->dev, "OXNAS DMA Registered\n");
+
+ return 0;
+
+dma_unregister:
+ dma_async_device_unregister(&dmadev->common);
+
+free_coherent:
+ dma_free_coherent(&pdev->dev, sizeof(struct oxnas_dma_sg_data),
+ dmadev->sg_data, dmadev->p_sg_data);
+
+disable_clks:
+ clk_disable_unprepare(dmadev->dma_clk);
+
+ return ret;
+}
+
+static int oxnas_dma_remove(struct platform_device *pdev)
+{
+ struct oxnas_dma_device *dmadev = platform_get_drvdata(pdev);
+
+ dma_async_device_unregister(&dmadev->common);
+
+ dma_free_coherent(&pdev->dev, sizeof(struct oxnas_dma_sg_data),
+ dmadev->sg_data, dmadev->p_sg_data);
+
+ clk_disable_unprepare(dmadev->dma_clk);
+
+ return 0;
+}
+
+static const struct of_device_id oxnas_dma_of_dev_id[] = {
+ { .compatible = "oxsemi,ox810se-dma", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, oxnas_dma_of_dev_id);
+
+static struct platform_driver oxnas_dma_driver = {
+ .probe = oxnas_dma_probe,
+ .remove = oxnas_dma_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "oxnas-dma",
+ .of_match_table = oxnas_dma_of_dev_id,
+ },
+};
+
+static int __init oxnas_dma_init_module(void)
+{
+ return platform_driver_register(&oxnas_dma_driver);
+}
+subsys_initcall(oxnas_dma_init_module);
+
+static void __exit oxnas_dma_exit_module(void)
+{
+ platform_driver_unregister(&oxnas_dma_driver);
+}
+module_exit(oxnas_dma_exit_module);
+
+MODULE_VERSION("1.0");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Neil Armstrong <narmstrong at baylibre.com>");
--
2.25.1
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