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![Christoph Hellwig](/assets/img/avatar_default.png)
ioremap has provided non-cached semantics by default since the Linux 2.6 days, so remove the additional ioremap_nocache interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Arnd Bergmann <arnd@arndb.de>
930 lines
25 KiB
C
930 lines
25 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* DMA driver for Altera mSGDMA IP core
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*
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* Copyright (C) 2017 Stefan Roese <sr@denx.de>
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*
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* Based on drivers/dma/xilinx/zynqmp_dma.c, which is:
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* Copyright (C) 2016 Xilinx, Inc. All rights reserved.
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*/
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#include <linux/bitops.h>
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#include <linux/delay.h>
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#include <linux/dma-mapping.h>
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#include <linux/dmapool.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/iopoll.h>
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#include <linux/module.h>
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#include <linux/platform_device.h>
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#include <linux/slab.h>
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#include "dmaengine.h"
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#define MSGDMA_MAX_TRANS_LEN U32_MAX
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#define MSGDMA_DESC_NUM 1024
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/**
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* struct msgdma_extended_desc - implements an extended descriptor
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* @read_addr_lo: data buffer source address low bits
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* @write_addr_lo: data buffer destination address low bits
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* @len: the number of bytes to transfer per descriptor
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* @burst_seq_num: bit 31:24 write burst
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* bit 23:16 read burst
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* bit 15:00 sequence number
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* @stride: bit 31:16 write stride
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* bit 15:00 read stride
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* @read_addr_hi: data buffer source address high bits
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* @write_addr_hi: data buffer destination address high bits
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* @control: characteristics of the transfer
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*/
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struct msgdma_extended_desc {
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u32 read_addr_lo;
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u32 write_addr_lo;
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u32 len;
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u32 burst_seq_num;
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u32 stride;
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u32 read_addr_hi;
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u32 write_addr_hi;
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u32 control;
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};
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/* mSGDMA descriptor control field bit definitions */
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#define MSGDMA_DESC_CTL_SET_CH(x) ((x) & 0xff)
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#define MSGDMA_DESC_CTL_GEN_SOP BIT(8)
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#define MSGDMA_DESC_CTL_GEN_EOP BIT(9)
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#define MSGDMA_DESC_CTL_PARK_READS BIT(10)
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#define MSGDMA_DESC_CTL_PARK_WRITES BIT(11)
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#define MSGDMA_DESC_CTL_END_ON_EOP BIT(12)
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#define MSGDMA_DESC_CTL_END_ON_LEN BIT(13)
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#define MSGDMA_DESC_CTL_TR_COMP_IRQ BIT(14)
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#define MSGDMA_DESC_CTL_EARLY_IRQ BIT(15)
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#define MSGDMA_DESC_CTL_TR_ERR_IRQ GENMASK(23, 16)
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#define MSGDMA_DESC_CTL_EARLY_DONE BIT(24)
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/*
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* Writing "1" the "go" bit commits the entire descriptor into the
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* descriptor FIFO(s)
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*/
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#define MSGDMA_DESC_CTL_GO BIT(31)
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/* Tx buffer control flags */
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#define MSGDMA_DESC_CTL_TX_FIRST (MSGDMA_DESC_CTL_GEN_SOP | \
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MSGDMA_DESC_CTL_TR_ERR_IRQ | \
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MSGDMA_DESC_CTL_GO)
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#define MSGDMA_DESC_CTL_TX_MIDDLE (MSGDMA_DESC_CTL_TR_ERR_IRQ | \
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MSGDMA_DESC_CTL_GO)
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#define MSGDMA_DESC_CTL_TX_LAST (MSGDMA_DESC_CTL_GEN_EOP | \
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MSGDMA_DESC_CTL_TR_COMP_IRQ | \
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MSGDMA_DESC_CTL_TR_ERR_IRQ | \
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MSGDMA_DESC_CTL_GO)
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#define MSGDMA_DESC_CTL_TX_SINGLE (MSGDMA_DESC_CTL_GEN_SOP | \
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MSGDMA_DESC_CTL_GEN_EOP | \
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MSGDMA_DESC_CTL_TR_COMP_IRQ | \
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MSGDMA_DESC_CTL_TR_ERR_IRQ | \
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MSGDMA_DESC_CTL_GO)
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#define MSGDMA_DESC_CTL_RX_SINGLE (MSGDMA_DESC_CTL_END_ON_EOP | \
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MSGDMA_DESC_CTL_END_ON_LEN | \
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MSGDMA_DESC_CTL_TR_COMP_IRQ | \
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MSGDMA_DESC_CTL_EARLY_IRQ | \
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MSGDMA_DESC_CTL_TR_ERR_IRQ | \
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MSGDMA_DESC_CTL_GO)
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/* mSGDMA extended descriptor stride definitions */
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#define MSGDMA_DESC_STRIDE_RD 0x00000001
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#define MSGDMA_DESC_STRIDE_WR 0x00010000
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#define MSGDMA_DESC_STRIDE_RW 0x00010001
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/* mSGDMA dispatcher control and status register map */
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#define MSGDMA_CSR_STATUS 0x00 /* Read / Clear */
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#define MSGDMA_CSR_CONTROL 0x04 /* Read / Write */
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#define MSGDMA_CSR_RW_FILL_LEVEL 0x08 /* 31:16 - write fill level */
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/* 15:00 - read fill level */
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#define MSGDMA_CSR_RESP_FILL_LEVEL 0x0c /* response FIFO fill level */
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#define MSGDMA_CSR_RW_SEQ_NUM 0x10 /* 31:16 - write seq number */
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/* 15:00 - read seq number */
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/* mSGDMA CSR status register bit definitions */
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#define MSGDMA_CSR_STAT_BUSY BIT(0)
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#define MSGDMA_CSR_STAT_DESC_BUF_EMPTY BIT(1)
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#define MSGDMA_CSR_STAT_DESC_BUF_FULL BIT(2)
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#define MSGDMA_CSR_STAT_RESP_BUF_EMPTY BIT(3)
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#define MSGDMA_CSR_STAT_RESP_BUF_FULL BIT(4)
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#define MSGDMA_CSR_STAT_STOPPED BIT(5)
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#define MSGDMA_CSR_STAT_RESETTING BIT(6)
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#define MSGDMA_CSR_STAT_STOPPED_ON_ERR BIT(7)
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#define MSGDMA_CSR_STAT_STOPPED_ON_EARLY BIT(8)
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#define MSGDMA_CSR_STAT_IRQ BIT(9)
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#define MSGDMA_CSR_STAT_MASK GENMASK(9, 0)
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#define MSGDMA_CSR_STAT_MASK_WITHOUT_IRQ GENMASK(8, 0)
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#define DESC_EMPTY (MSGDMA_CSR_STAT_DESC_BUF_EMPTY | \
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MSGDMA_CSR_STAT_RESP_BUF_EMPTY)
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/* mSGDMA CSR control register bit definitions */
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#define MSGDMA_CSR_CTL_STOP BIT(0)
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#define MSGDMA_CSR_CTL_RESET BIT(1)
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#define MSGDMA_CSR_CTL_STOP_ON_ERR BIT(2)
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#define MSGDMA_CSR_CTL_STOP_ON_EARLY BIT(3)
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#define MSGDMA_CSR_CTL_GLOBAL_INTR BIT(4)
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#define MSGDMA_CSR_CTL_STOP_DESCS BIT(5)
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/* mSGDMA CSR fill level bits */
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#define MSGDMA_CSR_WR_FILL_LEVEL_GET(v) (((v) & 0xffff0000) >> 16)
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#define MSGDMA_CSR_RD_FILL_LEVEL_GET(v) ((v) & 0x0000ffff)
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#define MSGDMA_CSR_RESP_FILL_LEVEL_GET(v) ((v) & 0x0000ffff)
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#define MSGDMA_CSR_SEQ_NUM_GET(v) (((v) & 0xffff0000) >> 16)
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/* mSGDMA response register map */
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#define MSGDMA_RESP_BYTES_TRANSFERRED 0x00
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#define MSGDMA_RESP_STATUS 0x04
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/* mSGDMA response register bit definitions */
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#define MSGDMA_RESP_EARLY_TERM BIT(8)
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#define MSGDMA_RESP_ERR_MASK 0xff
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/**
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* struct msgdma_sw_desc - implements a sw descriptor
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* @async_tx: support for the async_tx api
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* @hw_desc: assosiated HW descriptor
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* @free_list: node of the free SW descriprots list
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*/
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struct msgdma_sw_desc {
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struct dma_async_tx_descriptor async_tx;
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struct msgdma_extended_desc hw_desc;
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struct list_head node;
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struct list_head tx_list;
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};
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/**
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* struct msgdma_device - DMA device structure
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*/
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struct msgdma_device {
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spinlock_t lock;
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struct device *dev;
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struct tasklet_struct irq_tasklet;
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struct list_head pending_list;
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struct list_head free_list;
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struct list_head active_list;
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struct list_head done_list;
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u32 desc_free_cnt;
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bool idle;
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struct dma_device dmadev;
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struct dma_chan dmachan;
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dma_addr_t hw_desq;
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struct msgdma_sw_desc *sw_desq;
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unsigned int npendings;
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struct dma_slave_config slave_cfg;
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int irq;
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/* mSGDMA controller */
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void __iomem *csr;
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/* mSGDMA descriptors */
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void __iomem *desc;
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/* mSGDMA response */
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void __iomem *resp;
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};
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#define to_mdev(chan) container_of(chan, struct msgdma_device, dmachan)
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#define tx_to_desc(tx) container_of(tx, struct msgdma_sw_desc, async_tx)
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/**
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* msgdma_get_descriptor - Get the sw descriptor from the pool
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* @mdev: Pointer to the Altera mSGDMA device structure
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*
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* Return: The sw descriptor
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*/
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static struct msgdma_sw_desc *msgdma_get_descriptor(struct msgdma_device *mdev)
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{
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struct msgdma_sw_desc *desc;
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unsigned long flags;
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spin_lock_irqsave(&mdev->lock, flags);
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desc = list_first_entry(&mdev->free_list, struct msgdma_sw_desc, node);
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list_del(&desc->node);
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spin_unlock_irqrestore(&mdev->lock, flags);
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INIT_LIST_HEAD(&desc->tx_list);
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return desc;
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}
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/**
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* msgdma_free_descriptor - Issue pending transactions
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* @mdev: Pointer to the Altera mSGDMA device structure
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* @desc: Transaction descriptor pointer
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*/
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static void msgdma_free_descriptor(struct msgdma_device *mdev,
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struct msgdma_sw_desc *desc)
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{
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struct msgdma_sw_desc *child, *next;
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mdev->desc_free_cnt++;
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list_add_tail(&desc->node, &mdev->free_list);
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list_for_each_entry_safe(child, next, &desc->tx_list, node) {
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mdev->desc_free_cnt++;
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list_move_tail(&child->node, &mdev->free_list);
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}
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}
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/**
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* msgdma_free_desc_list - Free descriptors list
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* @mdev: Pointer to the Altera mSGDMA device structure
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* @list: List to parse and delete the descriptor
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*/
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static void msgdma_free_desc_list(struct msgdma_device *mdev,
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struct list_head *list)
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{
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struct msgdma_sw_desc *desc, *next;
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list_for_each_entry_safe(desc, next, list, node)
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msgdma_free_descriptor(mdev, desc);
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}
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/**
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* msgdma_desc_config - Configure the descriptor
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* @desc: Hw descriptor pointer
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* @dst: Destination buffer address
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* @src: Source buffer address
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* @len: Transfer length
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*/
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static void msgdma_desc_config(struct msgdma_extended_desc *desc,
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dma_addr_t dst, dma_addr_t src, size_t len,
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u32 stride)
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{
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/* Set lower 32bits of src & dst addresses in the descriptor */
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desc->read_addr_lo = lower_32_bits(src);
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desc->write_addr_lo = lower_32_bits(dst);
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/* Set upper 32bits of src & dst addresses in the descriptor */
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desc->read_addr_hi = upper_32_bits(src);
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desc->write_addr_hi = upper_32_bits(dst);
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desc->len = len;
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desc->stride = stride;
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desc->burst_seq_num = 0; /* 0 will result in max burst length */
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/*
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* Don't set interrupt on xfer end yet, this will be done later
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* for the "last" descriptor
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*/
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desc->control = MSGDMA_DESC_CTL_TR_ERR_IRQ | MSGDMA_DESC_CTL_GO |
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MSGDMA_DESC_CTL_END_ON_LEN;
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}
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/**
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* msgdma_desc_config_eod - Mark the descriptor as end descriptor
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* @desc: Hw descriptor pointer
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*/
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static void msgdma_desc_config_eod(struct msgdma_extended_desc *desc)
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{
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desc->control |= MSGDMA_DESC_CTL_TR_COMP_IRQ;
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}
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/**
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* msgdma_tx_submit - Submit DMA transaction
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* @tx: Async transaction descriptor pointer
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*
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* Return: cookie value
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*/
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static dma_cookie_t msgdma_tx_submit(struct dma_async_tx_descriptor *tx)
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{
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struct msgdma_device *mdev = to_mdev(tx->chan);
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struct msgdma_sw_desc *new;
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dma_cookie_t cookie;
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unsigned long flags;
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new = tx_to_desc(tx);
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spin_lock_irqsave(&mdev->lock, flags);
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cookie = dma_cookie_assign(tx);
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list_add_tail(&new->node, &mdev->pending_list);
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spin_unlock_irqrestore(&mdev->lock, flags);
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return cookie;
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}
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/**
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* msgdma_prep_memcpy - prepare descriptors for memcpy transaction
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* @dchan: DMA channel
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* @dma_dst: Destination buffer address
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* @dma_src: Source buffer address
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* @len: Transfer length
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* @flags: transfer ack flags
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*
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* Return: Async transaction descriptor on success and NULL on failure
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*/
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static struct dma_async_tx_descriptor *
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msgdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
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dma_addr_t dma_src, size_t len, ulong flags)
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{
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struct msgdma_device *mdev = to_mdev(dchan);
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struct msgdma_sw_desc *new, *first = NULL;
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struct msgdma_extended_desc *desc;
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size_t copy;
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u32 desc_cnt;
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unsigned long irqflags;
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desc_cnt = DIV_ROUND_UP(len, MSGDMA_MAX_TRANS_LEN);
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spin_lock_irqsave(&mdev->lock, irqflags);
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if (desc_cnt > mdev->desc_free_cnt) {
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spin_unlock_irqrestore(&mdev->lock, irqflags);
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dev_dbg(mdev->dev, "mdev %p descs are not available\n", mdev);
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return NULL;
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}
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mdev->desc_free_cnt -= desc_cnt;
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spin_unlock_irqrestore(&mdev->lock, irqflags);
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do {
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/* Allocate and populate the descriptor */
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new = msgdma_get_descriptor(mdev);
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copy = min_t(size_t, len, MSGDMA_MAX_TRANS_LEN);
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desc = &new->hw_desc;
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msgdma_desc_config(desc, dma_dst, dma_src, copy,
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MSGDMA_DESC_STRIDE_RW);
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len -= copy;
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dma_src += copy;
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dma_dst += copy;
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if (!first)
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first = new;
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else
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list_add_tail(&new->node, &first->tx_list);
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} while (len);
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msgdma_desc_config_eod(desc);
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async_tx_ack(&first->async_tx);
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first->async_tx.flags = flags;
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return &first->async_tx;
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}
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/**
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* msgdma_prep_slave_sg - prepare descriptors for a slave sg transaction
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*
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* @dchan: DMA channel
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* @sgl: Destination scatter list
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* @sg_len: Number of entries in destination scatter list
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* @dir: DMA transfer direction
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* @flags: transfer ack flags
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* @context: transfer context (unused)
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*/
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static struct dma_async_tx_descriptor *
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msgdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
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unsigned int sg_len, enum dma_transfer_direction dir,
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unsigned long flags, void *context)
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{
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struct msgdma_device *mdev = to_mdev(dchan);
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struct dma_slave_config *cfg = &mdev->slave_cfg;
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struct msgdma_sw_desc *new, *first = NULL;
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void *desc = NULL;
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size_t len, avail;
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dma_addr_t dma_dst, dma_src;
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u32 desc_cnt = 0, i;
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struct scatterlist *sg;
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u32 stride;
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unsigned long irqflags;
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for_each_sg(sgl, sg, sg_len, i)
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desc_cnt += DIV_ROUND_UP(sg_dma_len(sg), MSGDMA_MAX_TRANS_LEN);
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spin_lock_irqsave(&mdev->lock, irqflags);
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if (desc_cnt > mdev->desc_free_cnt) {
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spin_unlock_irqrestore(&mdev->lock, irqflags);
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dev_dbg(mdev->dev, "mdev %p descs are not available\n", mdev);
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return NULL;
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}
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mdev->desc_free_cnt -= desc_cnt;
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spin_unlock_irqrestore(&mdev->lock, irqflags);
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avail = sg_dma_len(sgl);
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/* Run until we are out of scatterlist entries */
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while (true) {
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/* Allocate and populate the descriptor */
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new = msgdma_get_descriptor(mdev);
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desc = &new->hw_desc;
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len = min_t(size_t, avail, MSGDMA_MAX_TRANS_LEN);
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if (dir == DMA_MEM_TO_DEV) {
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dma_src = sg_dma_address(sgl) + sg_dma_len(sgl) - avail;
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dma_dst = cfg->dst_addr;
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stride = MSGDMA_DESC_STRIDE_RD;
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} else {
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dma_src = cfg->src_addr;
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dma_dst = sg_dma_address(sgl) + sg_dma_len(sgl) - avail;
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stride = MSGDMA_DESC_STRIDE_WR;
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}
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msgdma_desc_config(desc, dma_dst, dma_src, len, stride);
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avail -= len;
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if (!first)
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first = new;
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else
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list_add_tail(&new->node, &first->tx_list);
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/* Fetch the next scatterlist entry */
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if (avail == 0) {
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if (sg_len == 0)
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break;
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sgl = sg_next(sgl);
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if (sgl == NULL)
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break;
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sg_len--;
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avail = sg_dma_len(sgl);
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}
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}
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msgdma_desc_config_eod(desc);
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first->async_tx.flags = flags;
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return &first->async_tx;
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}
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static int msgdma_dma_config(struct dma_chan *dchan,
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struct dma_slave_config *config)
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{
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struct msgdma_device *mdev = to_mdev(dchan);
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memcpy(&mdev->slave_cfg, config, sizeof(*config));
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|
|
|
return 0;
|
|
}
|
|
|
|
static void msgdma_reset(struct msgdma_device *mdev)
|
|
{
|
|
u32 val;
|
|
int ret;
|
|
|
|
/* Reset mSGDMA */
|
|
iowrite32(MSGDMA_CSR_STAT_MASK, mdev->csr + MSGDMA_CSR_STATUS);
|
|
iowrite32(MSGDMA_CSR_CTL_RESET, mdev->csr + MSGDMA_CSR_CONTROL);
|
|
|
|
ret = readl_poll_timeout(mdev->csr + MSGDMA_CSR_STATUS, val,
|
|
(val & MSGDMA_CSR_STAT_RESETTING) == 0,
|
|
1, 10000);
|
|
if (ret)
|
|
dev_err(mdev->dev, "DMA channel did not reset\n");
|
|
|
|
/* Clear all status bits */
|
|
iowrite32(MSGDMA_CSR_STAT_MASK, mdev->csr + MSGDMA_CSR_STATUS);
|
|
|
|
/* Enable the DMA controller including interrupts */
|
|
iowrite32(MSGDMA_CSR_CTL_STOP_ON_ERR | MSGDMA_CSR_CTL_STOP_ON_EARLY |
|
|
MSGDMA_CSR_CTL_GLOBAL_INTR, mdev->csr + MSGDMA_CSR_CONTROL);
|
|
|
|
mdev->idle = true;
|
|
};
|
|
|
|
static void msgdma_copy_one(struct msgdma_device *mdev,
|
|
struct msgdma_sw_desc *desc)
|
|
{
|
|
void __iomem *hw_desc = mdev->desc;
|
|
|
|
/*
|
|
* Check if the DESC FIFO it not full. If its full, we need to wait
|
|
* for at least one entry to become free again
|
|
*/
|
|
while (ioread32(mdev->csr + MSGDMA_CSR_STATUS) &
|
|
MSGDMA_CSR_STAT_DESC_BUF_FULL)
|
|
mdelay(1);
|
|
|
|
/*
|
|
* The descriptor needs to get copied into the descriptor FIFO
|
|
* of the DMA controller. The descriptor will get flushed to the
|
|
* FIFO, once the last word (control word) is written. Since we
|
|
* are not 100% sure that memcpy() writes all word in the "correct"
|
|
* oder (address from low to high) on all architectures, we make
|
|
* sure this control word is written last by single coding it and
|
|
* adding some write-barriers here.
|
|
*/
|
|
memcpy((void __force *)hw_desc, &desc->hw_desc,
|
|
sizeof(desc->hw_desc) - sizeof(u32));
|
|
|
|
/* Write control word last to flush this descriptor into the FIFO */
|
|
mdev->idle = false;
|
|
wmb();
|
|
iowrite32(desc->hw_desc.control, hw_desc +
|
|
offsetof(struct msgdma_extended_desc, control));
|
|
wmb();
|
|
}
|
|
|
|
/**
|
|
* msgdma_copy_desc_to_fifo - copy descriptor(s) into controller FIFO
|
|
* @mdev: Pointer to the Altera mSGDMA device structure
|
|
* @desc: Transaction descriptor pointer
|
|
*/
|
|
static void msgdma_copy_desc_to_fifo(struct msgdma_device *mdev,
|
|
struct msgdma_sw_desc *desc)
|
|
{
|
|
struct msgdma_sw_desc *sdesc, *next;
|
|
|
|
msgdma_copy_one(mdev, desc);
|
|
|
|
list_for_each_entry_safe(sdesc, next, &desc->tx_list, node)
|
|
msgdma_copy_one(mdev, sdesc);
|
|
}
|
|
|
|
/**
|
|
* msgdma_start_transfer - Initiate the new transfer
|
|
* @mdev: Pointer to the Altera mSGDMA device structure
|
|
*/
|
|
static void msgdma_start_transfer(struct msgdma_device *mdev)
|
|
{
|
|
struct msgdma_sw_desc *desc;
|
|
|
|
if (!mdev->idle)
|
|
return;
|
|
|
|
desc = list_first_entry_or_null(&mdev->pending_list,
|
|
struct msgdma_sw_desc, node);
|
|
if (!desc)
|
|
return;
|
|
|
|
list_splice_tail_init(&mdev->pending_list, &mdev->active_list);
|
|
msgdma_copy_desc_to_fifo(mdev, desc);
|
|
}
|
|
|
|
/**
|
|
* msgdma_issue_pending - Issue pending transactions
|
|
* @chan: DMA channel pointer
|
|
*/
|
|
static void msgdma_issue_pending(struct dma_chan *chan)
|
|
{
|
|
struct msgdma_device *mdev = to_mdev(chan);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&mdev->lock, flags);
|
|
msgdma_start_transfer(mdev);
|
|
spin_unlock_irqrestore(&mdev->lock, flags);
|
|
}
|
|
|
|
/**
|
|
* msgdma_chan_desc_cleanup - Cleanup the completed descriptors
|
|
* @mdev: Pointer to the Altera mSGDMA device structure
|
|
*/
|
|
static void msgdma_chan_desc_cleanup(struct msgdma_device *mdev)
|
|
{
|
|
struct msgdma_sw_desc *desc, *next;
|
|
|
|
list_for_each_entry_safe(desc, next, &mdev->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(&mdev->lock);
|
|
callback(callback_param);
|
|
spin_lock(&mdev->lock);
|
|
}
|
|
|
|
/* Run any dependencies, then free the descriptor */
|
|
msgdma_free_descriptor(mdev, desc);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* msgdma_complete_descriptor - Mark the active descriptor as complete
|
|
* @mdev: Pointer to the Altera mSGDMA device structure
|
|
*/
|
|
static void msgdma_complete_descriptor(struct msgdma_device *mdev)
|
|
{
|
|
struct msgdma_sw_desc *desc;
|
|
|
|
desc = list_first_entry_or_null(&mdev->active_list,
|
|
struct msgdma_sw_desc, node);
|
|
if (!desc)
|
|
return;
|
|
list_del(&desc->node);
|
|
dma_cookie_complete(&desc->async_tx);
|
|
list_add_tail(&desc->node, &mdev->done_list);
|
|
}
|
|
|
|
/**
|
|
* msgdma_free_descriptors - Free channel descriptors
|
|
* @mdev: Pointer to the Altera mSGDMA device structure
|
|
*/
|
|
static void msgdma_free_descriptors(struct msgdma_device *mdev)
|
|
{
|
|
msgdma_free_desc_list(mdev, &mdev->active_list);
|
|
msgdma_free_desc_list(mdev, &mdev->pending_list);
|
|
msgdma_free_desc_list(mdev, &mdev->done_list);
|
|
}
|
|
|
|
/**
|
|
* msgdma_free_chan_resources - Free channel resources
|
|
* @dchan: DMA channel pointer
|
|
*/
|
|
static void msgdma_free_chan_resources(struct dma_chan *dchan)
|
|
{
|
|
struct msgdma_device *mdev = to_mdev(dchan);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&mdev->lock, flags);
|
|
msgdma_free_descriptors(mdev);
|
|
spin_unlock_irqrestore(&mdev->lock, flags);
|
|
kfree(mdev->sw_desq);
|
|
}
|
|
|
|
/**
|
|
* msgdma_alloc_chan_resources - Allocate channel resources
|
|
* @dchan: DMA channel
|
|
*
|
|
* Return: Number of descriptors on success and failure value on error
|
|
*/
|
|
static int msgdma_alloc_chan_resources(struct dma_chan *dchan)
|
|
{
|
|
struct msgdma_device *mdev = to_mdev(dchan);
|
|
struct msgdma_sw_desc *desc;
|
|
int i;
|
|
|
|
mdev->sw_desq = kcalloc(MSGDMA_DESC_NUM, sizeof(*desc), GFP_NOWAIT);
|
|
if (!mdev->sw_desq)
|
|
return -ENOMEM;
|
|
|
|
mdev->idle = true;
|
|
mdev->desc_free_cnt = MSGDMA_DESC_NUM;
|
|
|
|
INIT_LIST_HEAD(&mdev->free_list);
|
|
|
|
for (i = 0; i < MSGDMA_DESC_NUM; i++) {
|
|
desc = mdev->sw_desq + i;
|
|
dma_async_tx_descriptor_init(&desc->async_tx, &mdev->dmachan);
|
|
desc->async_tx.tx_submit = msgdma_tx_submit;
|
|
list_add_tail(&desc->node, &mdev->free_list);
|
|
}
|
|
|
|
return MSGDMA_DESC_NUM;
|
|
}
|
|
|
|
/**
|
|
* msgdma_tasklet - Schedule completion tasklet
|
|
* @data: Pointer to the Altera sSGDMA channel structure
|
|
*/
|
|
static void msgdma_tasklet(unsigned long data)
|
|
{
|
|
struct msgdma_device *mdev = (struct msgdma_device *)data;
|
|
u32 count;
|
|
u32 __maybe_unused size;
|
|
u32 __maybe_unused status;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&mdev->lock, flags);
|
|
|
|
/* Read number of responses that are available */
|
|
count = ioread32(mdev->csr + MSGDMA_CSR_RESP_FILL_LEVEL);
|
|
dev_dbg(mdev->dev, "%s (%d): response count=%d\n",
|
|
__func__, __LINE__, count);
|
|
|
|
while (count--) {
|
|
/*
|
|
* Read both longwords to purge this response from the FIFO
|
|
* On Avalon-MM implementations, size and status do not
|
|
* have any real values, like transferred bytes or error
|
|
* bits. So we need to just drop these values.
|
|
*/
|
|
size = ioread32(mdev->resp + MSGDMA_RESP_BYTES_TRANSFERRED);
|
|
status = ioread32(mdev->resp + MSGDMA_RESP_STATUS);
|
|
|
|
msgdma_complete_descriptor(mdev);
|
|
msgdma_chan_desc_cleanup(mdev);
|
|
}
|
|
|
|
spin_unlock_irqrestore(&mdev->lock, flags);
|
|
}
|
|
|
|
/**
|
|
* msgdma_irq_handler - Altera mSGDMA Interrupt handler
|
|
* @irq: IRQ number
|
|
* @data: Pointer to the Altera mSGDMA device structure
|
|
*
|
|
* Return: IRQ_HANDLED/IRQ_NONE
|
|
*/
|
|
static irqreturn_t msgdma_irq_handler(int irq, void *data)
|
|
{
|
|
struct msgdma_device *mdev = data;
|
|
u32 status;
|
|
|
|
status = ioread32(mdev->csr + MSGDMA_CSR_STATUS);
|
|
if ((status & MSGDMA_CSR_STAT_BUSY) == 0) {
|
|
/* Start next transfer if the DMA controller is idle */
|
|
spin_lock(&mdev->lock);
|
|
mdev->idle = true;
|
|
msgdma_start_transfer(mdev);
|
|
spin_unlock(&mdev->lock);
|
|
}
|
|
|
|
tasklet_schedule(&mdev->irq_tasklet);
|
|
|
|
/* Clear interrupt in mSGDMA controller */
|
|
iowrite32(MSGDMA_CSR_STAT_IRQ, mdev->csr + MSGDMA_CSR_STATUS);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/**
|
|
* msgdma_chan_remove - Channel remove function
|
|
* @mdev: Pointer to the Altera mSGDMA device structure
|
|
*/
|
|
static void msgdma_dev_remove(struct msgdma_device *mdev)
|
|
{
|
|
if (!mdev)
|
|
return;
|
|
|
|
devm_free_irq(mdev->dev, mdev->irq, mdev);
|
|
tasklet_kill(&mdev->irq_tasklet);
|
|
list_del(&mdev->dmachan.device_node);
|
|
}
|
|
|
|
static int request_and_map(struct platform_device *pdev, const char *name,
|
|
struct resource **res, void __iomem **ptr)
|
|
{
|
|
struct resource *region;
|
|
struct device *device = &pdev->dev;
|
|
|
|
*res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
|
|
if (*res == NULL) {
|
|
dev_err(device, "resource %s not defined\n", name);
|
|
return -ENODEV;
|
|
}
|
|
|
|
region = devm_request_mem_region(device, (*res)->start,
|
|
resource_size(*res), dev_name(device));
|
|
if (region == NULL) {
|
|
dev_err(device, "unable to request %s\n", name);
|
|
return -EBUSY;
|
|
}
|
|
|
|
*ptr = devm_ioremap(device, region->start,
|
|
resource_size(region));
|
|
if (*ptr == NULL) {
|
|
dev_err(device, "ioremap of %s failed!", name);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* msgdma_probe - Driver probe function
|
|
* @pdev: Pointer to the platform_device structure
|
|
*
|
|
* Return: '0' on success and failure value on error
|
|
*/
|
|
static int msgdma_probe(struct platform_device *pdev)
|
|
{
|
|
struct msgdma_device *mdev;
|
|
struct dma_device *dma_dev;
|
|
struct resource *dma_res;
|
|
int ret;
|
|
|
|
mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_NOWAIT);
|
|
if (!mdev)
|
|
return -ENOMEM;
|
|
|
|
mdev->dev = &pdev->dev;
|
|
|
|
/* Map CSR space */
|
|
ret = request_and_map(pdev, "csr", &dma_res, &mdev->csr);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Map (extended) descriptor space */
|
|
ret = request_and_map(pdev, "desc", &dma_res, &mdev->desc);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Map response space */
|
|
ret = request_and_map(pdev, "resp", &dma_res, &mdev->resp);
|
|
if (ret)
|
|
return ret;
|
|
|
|
platform_set_drvdata(pdev, mdev);
|
|
|
|
/* Get interrupt nr from platform data */
|
|
mdev->irq = platform_get_irq(pdev, 0);
|
|
if (mdev->irq < 0)
|
|
return -ENXIO;
|
|
|
|
ret = devm_request_irq(&pdev->dev, mdev->irq, msgdma_irq_handler,
|
|
0, dev_name(&pdev->dev), mdev);
|
|
if (ret)
|
|
return ret;
|
|
|
|
tasklet_init(&mdev->irq_tasklet, msgdma_tasklet, (unsigned long)mdev);
|
|
|
|
dma_cookie_init(&mdev->dmachan);
|
|
|
|
spin_lock_init(&mdev->lock);
|
|
|
|
INIT_LIST_HEAD(&mdev->active_list);
|
|
INIT_LIST_HEAD(&mdev->pending_list);
|
|
INIT_LIST_HEAD(&mdev->done_list);
|
|
INIT_LIST_HEAD(&mdev->free_list);
|
|
|
|
dma_dev = &mdev->dmadev;
|
|
|
|
/* Set DMA capabilities */
|
|
dma_cap_zero(dma_dev->cap_mask);
|
|
dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
|
|
dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
|
|
|
|
dma_dev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
|
|
dma_dev->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
|
|
dma_dev->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM) |
|
|
BIT(DMA_MEM_TO_MEM);
|
|
dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
|
|
|
|
/* Init DMA link list */
|
|
INIT_LIST_HEAD(&dma_dev->channels);
|
|
|
|
/* Set base routines */
|
|
dma_dev->device_tx_status = dma_cookie_status;
|
|
dma_dev->device_issue_pending = msgdma_issue_pending;
|
|
dma_dev->dev = &pdev->dev;
|
|
|
|
dma_dev->copy_align = DMAENGINE_ALIGN_4_BYTES;
|
|
dma_dev->device_prep_dma_memcpy = msgdma_prep_memcpy;
|
|
dma_dev->device_prep_slave_sg = msgdma_prep_slave_sg;
|
|
dma_dev->device_config = msgdma_dma_config;
|
|
|
|
dma_dev->device_alloc_chan_resources = msgdma_alloc_chan_resources;
|
|
dma_dev->device_free_chan_resources = msgdma_free_chan_resources;
|
|
|
|
mdev->dmachan.device = dma_dev;
|
|
list_add_tail(&mdev->dmachan.device_node, &dma_dev->channels);
|
|
|
|
/* Set DMA mask to 64 bits */
|
|
ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
|
|
if (ret) {
|
|
dev_warn(&pdev->dev, "unable to set coherent mask to 64");
|
|
ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
|
|
if (ret)
|
|
goto fail;
|
|
}
|
|
|
|
msgdma_reset(mdev);
|
|
|
|
ret = dma_async_device_register(dma_dev);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
dev_notice(&pdev->dev, "Altera mSGDMA driver probe success\n");
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
msgdma_dev_remove(mdev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* msgdma_dma_remove - Driver remove function
|
|
* @pdev: Pointer to the platform_device structure
|
|
*
|
|
* Return: Always '0'
|
|
*/
|
|
static int msgdma_remove(struct platform_device *pdev)
|
|
{
|
|
struct msgdma_device *mdev = platform_get_drvdata(pdev);
|
|
|
|
dma_async_device_unregister(&mdev->dmadev);
|
|
msgdma_dev_remove(mdev);
|
|
|
|
dev_notice(&pdev->dev, "Altera mSGDMA driver removed\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver msgdma_driver = {
|
|
.driver = {
|
|
.name = "altera-msgdma",
|
|
},
|
|
.probe = msgdma_probe,
|
|
.remove = msgdma_remove,
|
|
};
|
|
|
|
module_platform_driver(msgdma_driver);
|
|
|
|
MODULE_ALIAS("platform:altera-msgdma");
|
|
MODULE_DESCRIPTION("Altera mSGDMA driver");
|
|
MODULE_AUTHOR("Stefan Roese <sr@denx.de>");
|
|
MODULE_LICENSE("GPL");
|