706 lines
19 KiB
C
706 lines
19 KiB
C
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// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Driver for the Loongson LS2X APB DMA Controller
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*
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* Copyright (C) 2017-2023 Loongson Corporation
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*/
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#include <linux/clk.h>
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#include <linux/dma-mapping.h>
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#include <linux/dmapool.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/io-64-nonatomic-lo-hi.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/of_dma.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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#include "virt-dma.h"
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/* Global Configuration Register */
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#define LDMA_ORDER_ERG 0x0
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/* Bitfield definitions */
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/* Bitfields in Global Configuration Register */
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#define LDMA_64BIT_EN BIT(0) /* 1: 64 bit support */
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#define LDMA_UNCOHERENT_EN BIT(1) /* 0: cache, 1: uncache */
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#define LDMA_ASK_VALID BIT(2)
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#define LDMA_START BIT(3) /* DMA start operation */
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#define LDMA_STOP BIT(4) /* DMA stop operation */
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#define LDMA_CONFIG_MASK GENMASK(4, 0) /* DMA controller config bits mask */
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/* Bitfields in ndesc_addr field of HW decriptor */
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#define LDMA_DESC_EN BIT(0) /*1: The next descriptor is valid */
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#define LDMA_DESC_ADDR_LOW GENMASK(31, 1)
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/* Bitfields in cmd field of HW decriptor */
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#define LDMA_INT BIT(1) /* Enable DMA interrupts */
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#define LDMA_DATA_DIRECTION BIT(12) /* 1: write to device, 0: read from device */
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#define LDMA_SLAVE_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
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BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
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#define LDMA_MAX_TRANS_LEN U32_MAX
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/*-- descriptors -----------------------------------------------------*/
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/*
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* struct ls2x_dma_hw_desc - DMA HW descriptor
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* @ndesc_addr: the next descriptor low address.
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* @mem_addr: memory low address.
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* @apb_addr: device buffer address.
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* @len: length of a piece of carried content, in words.
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* @step_len: length between two moved memory data blocks.
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* @step_times: number of blocks to be carried in a single DMA operation.
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* @cmd: descriptor command or state.
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* @stats: DMA status.
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* @high_ndesc_addr: the next descriptor high address.
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* @high_mem_addr: memory high address.
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* @reserved: reserved
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*/
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struct ls2x_dma_hw_desc {
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u32 ndesc_addr;
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u32 mem_addr;
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u32 apb_addr;
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u32 len;
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u32 step_len;
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u32 step_times;
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u32 cmd;
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u32 stats;
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u32 high_ndesc_addr;
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u32 high_mem_addr;
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u32 reserved[2];
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} __packed;
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/*
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* struct ls2x_dma_sg - ls2x dma scatter gather entry
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* @hw: the pointer to DMA HW descriptor.
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* @llp: physical address of the DMA HW descriptor.
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* @phys: destination or source address(mem).
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* @len: number of Bytes to read.
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*/
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struct ls2x_dma_sg {
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struct ls2x_dma_hw_desc *hw;
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dma_addr_t llp;
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dma_addr_t phys;
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u32 len;
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};
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/*
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* struct ls2x_dma_desc - software descriptor
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* @vdesc: pointer to the virtual dma descriptor.
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* @cyclic: flag to dma cyclic
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* @burst_size: burst size of transaction, in words.
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* @desc_num: number of sg entries.
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* @direction: transfer direction, to or from device.
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* @status: dma controller status.
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* @sg: array of sgs.
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*/
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struct ls2x_dma_desc {
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struct virt_dma_desc vdesc;
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bool cyclic;
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size_t burst_size;
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u32 desc_num;
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enum dma_transfer_direction direction;
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enum dma_status status;
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struct ls2x_dma_sg sg[] __counted_by(desc_num);
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};
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/*-- Channels --------------------------------------------------------*/
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/*
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* struct ls2x_dma_chan - internal representation of an LS2X APB DMA channel
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* @vchan: virtual dma channel entry.
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* @desc: pointer to the ls2x sw dma descriptor.
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* @pool: hw desc table
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* @irq: irq line
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* @sconfig: configuration for slave transfers, passed via .device_config
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*/
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struct ls2x_dma_chan {
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struct virt_dma_chan vchan;
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struct ls2x_dma_desc *desc;
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void *pool;
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int irq;
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struct dma_slave_config sconfig;
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};
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/*-- Controller ------------------------------------------------------*/
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/*
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* struct ls2x_dma_priv - LS2X APB DMAC specific information
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* @ddev: dmaengine dma_device object members
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* @dma_clk: DMAC clock source
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* @regs: memory mapped register base
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* @lchan: channel to store ls2x_dma_chan structures
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*/
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struct ls2x_dma_priv {
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struct dma_device ddev;
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struct clk *dma_clk;
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void __iomem *regs;
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struct ls2x_dma_chan lchan;
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};
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/*-- Helper functions ------------------------------------------------*/
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static inline struct ls2x_dma_desc *to_ldma_desc(struct virt_dma_desc *vdesc)
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{
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return container_of(vdesc, struct ls2x_dma_desc, vdesc);
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}
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static inline struct ls2x_dma_chan *to_ldma_chan(struct dma_chan *chan)
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{
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return container_of(chan, struct ls2x_dma_chan, vchan.chan);
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}
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static inline struct ls2x_dma_priv *to_ldma_priv(struct dma_device *ddev)
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{
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return container_of(ddev, struct ls2x_dma_priv, ddev);
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}
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static struct device *chan2dev(struct dma_chan *chan)
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{
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return &chan->dev->device;
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}
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static void ls2x_dma_desc_free(struct virt_dma_desc *vdesc)
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{
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struct ls2x_dma_chan *lchan = to_ldma_chan(vdesc->tx.chan);
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struct ls2x_dma_desc *desc = to_ldma_desc(vdesc);
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int i;
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for (i = 0; i < desc->desc_num; i++) {
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if (desc->sg[i].hw)
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dma_pool_free(lchan->pool, desc->sg[i].hw,
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desc->sg[i].llp);
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}
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kfree(desc);
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}
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static void ls2x_dma_write_cmd(struct ls2x_dma_chan *lchan, bool cmd)
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{
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struct ls2x_dma_priv *priv = to_ldma_priv(lchan->vchan.chan.device);
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u64 val;
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val = lo_hi_readq(priv->regs + LDMA_ORDER_ERG) & ~LDMA_CONFIG_MASK;
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val |= LDMA_64BIT_EN | cmd;
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lo_hi_writeq(val, priv->regs + LDMA_ORDER_ERG);
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}
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static void ls2x_dma_start_transfer(struct ls2x_dma_chan *lchan)
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{
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struct ls2x_dma_priv *priv = to_ldma_priv(lchan->vchan.chan.device);
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struct ls2x_dma_sg *ldma_sg;
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struct virt_dma_desc *vdesc;
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u64 val;
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/* Get the next descriptor */
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vdesc = vchan_next_desc(&lchan->vchan);
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if (!vdesc) {
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lchan->desc = NULL;
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return;
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}
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list_del(&vdesc->node);
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lchan->desc = to_ldma_desc(vdesc);
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ldma_sg = &lchan->desc->sg[0];
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/* Start DMA */
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lo_hi_writeq(0, priv->regs + LDMA_ORDER_ERG);
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val = (ldma_sg->llp & ~LDMA_CONFIG_MASK) | LDMA_64BIT_EN | LDMA_START;
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lo_hi_writeq(val, priv->regs + LDMA_ORDER_ERG);
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}
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static size_t ls2x_dmac_detect_burst(struct ls2x_dma_chan *lchan)
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{
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u32 maxburst, buswidth;
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/* Reject definitely invalid configurations */
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if ((lchan->sconfig.src_addr_width & LDMA_SLAVE_BUSWIDTHS) &&
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(lchan->sconfig.dst_addr_width & LDMA_SLAVE_BUSWIDTHS))
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return 0;
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if (lchan->sconfig.direction == DMA_MEM_TO_DEV) {
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maxburst = lchan->sconfig.dst_maxburst;
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buswidth = lchan->sconfig.dst_addr_width;
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} else {
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maxburst = lchan->sconfig.src_maxburst;
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buswidth = lchan->sconfig.src_addr_width;
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}
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/* If maxburst is zero, fallback to LDMA_MAX_TRANS_LEN */
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return maxburst ? (maxburst * buswidth) >> 2 : LDMA_MAX_TRANS_LEN;
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}
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static void ls2x_dma_fill_desc(struct ls2x_dma_chan *lchan, u32 sg_index,
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struct ls2x_dma_desc *desc)
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{
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struct ls2x_dma_sg *ldma_sg = &desc->sg[sg_index];
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u32 num_segments, segment_size;
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if (desc->direction == DMA_MEM_TO_DEV) {
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ldma_sg->hw->cmd = LDMA_INT | LDMA_DATA_DIRECTION;
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ldma_sg->hw->apb_addr = lchan->sconfig.dst_addr;
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} else {
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ldma_sg->hw->cmd = LDMA_INT;
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ldma_sg->hw->apb_addr = lchan->sconfig.src_addr;
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}
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ldma_sg->hw->mem_addr = lower_32_bits(ldma_sg->phys);
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ldma_sg->hw->high_mem_addr = upper_32_bits(ldma_sg->phys);
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/* Split into multiple equally sized segments if necessary */
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num_segments = DIV_ROUND_UP((ldma_sg->len + 3) >> 2, desc->burst_size);
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segment_size = DIV_ROUND_UP((ldma_sg->len + 3) >> 2, num_segments);
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/* Word count register takes input in words */
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ldma_sg->hw->len = segment_size;
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ldma_sg->hw->step_times = num_segments;
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ldma_sg->hw->step_len = 0;
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/* lets make a link list */
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if (sg_index) {
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desc->sg[sg_index - 1].hw->ndesc_addr = ldma_sg->llp | LDMA_DESC_EN;
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desc->sg[sg_index - 1].hw->high_ndesc_addr = upper_32_bits(ldma_sg->llp);
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}
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}
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/*-- DMA Engine API --------------------------------------------------*/
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/*
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* ls2x_dma_alloc_chan_resources - allocate resources for DMA channel
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* @chan: allocate descriptor resources for this channel
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*
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* return - the number of allocated descriptors
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*/
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static int ls2x_dma_alloc_chan_resources(struct dma_chan *chan)
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{
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struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
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/* Create a pool of consistent memory blocks for hardware descriptors */
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lchan->pool = dma_pool_create(dev_name(chan2dev(chan)),
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chan->device->dev, PAGE_SIZE,
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__alignof__(struct ls2x_dma_hw_desc), 0);
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if (!lchan->pool) {
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dev_err(chan2dev(chan), "No memory for descriptors\n");
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return -ENOMEM;
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}
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return 1;
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}
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/*
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* ls2x_dma_free_chan_resources - free all channel resources
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* @chan: DMA channel
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*/
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static void ls2x_dma_free_chan_resources(struct dma_chan *chan)
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{
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struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
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vchan_free_chan_resources(to_virt_chan(chan));
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dma_pool_destroy(lchan->pool);
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lchan->pool = NULL;
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}
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/*
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* ls2x_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
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* @chan: DMA channel
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* @sgl: scatterlist to transfer to/from
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* @sg_len: number of entries in @scatterlist
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* @direction: DMA direction
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* @flags: tx descriptor status flags
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* @context: transaction context (ignored)
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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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ls2x_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
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u32 sg_len, enum dma_transfer_direction direction,
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unsigned long flags, void *context)
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{
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struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
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struct ls2x_dma_desc *desc;
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struct scatterlist *sg;
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size_t burst_size;
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int i;
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if (unlikely(!sg_len || !is_slave_direction(direction)))
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return NULL;
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burst_size = ls2x_dmac_detect_burst(lchan);
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if (!burst_size)
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return NULL;
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desc = kzalloc(struct_size(desc, sg, sg_len), GFP_NOWAIT);
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if (!desc)
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return NULL;
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desc->desc_num = sg_len;
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desc->direction = direction;
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desc->burst_size = burst_size;
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for_each_sg(sgl, sg, sg_len, i) {
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struct ls2x_dma_sg *ldma_sg = &desc->sg[i];
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/* Allocate DMA capable memory for hardware descriptor */
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ldma_sg->hw = dma_pool_alloc(lchan->pool, GFP_NOWAIT, &ldma_sg->llp);
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if (!ldma_sg->hw) {
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desc->desc_num = i;
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ls2x_dma_desc_free(&desc->vdesc);
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return NULL;
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}
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ldma_sg->phys = sg_dma_address(sg);
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ldma_sg->len = sg_dma_len(sg);
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ls2x_dma_fill_desc(lchan, i, desc);
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}
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/* Setting the last descriptor enable bit */
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desc->sg[sg_len - 1].hw->ndesc_addr &= ~LDMA_DESC_EN;
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desc->status = DMA_IN_PROGRESS;
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return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags);
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}
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/*
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* ls2x_dma_prep_dma_cyclic - prepare the cyclic DMA transfer
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* @chan: the DMA channel to prepare
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* @buf_addr: physical DMA address where the buffer starts
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* @buf_len: total number of bytes for the entire buffer
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* @period_len: number of bytes for each period
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* @direction: transfer direction, to or from device
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* @flags: tx descriptor status 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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ls2x_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
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size_t period_len, enum dma_transfer_direction direction,
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unsigned long flags)
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{
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struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
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struct ls2x_dma_desc *desc;
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size_t burst_size;
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u32 num_periods;
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int i;
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if (unlikely(!buf_len || !period_len))
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return NULL;
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if (unlikely(!is_slave_direction(direction)))
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return NULL;
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burst_size = ls2x_dmac_detect_burst(lchan);
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if (!burst_size)
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return NULL;
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num_periods = buf_len / period_len;
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desc = kzalloc(struct_size(desc, sg, num_periods), GFP_NOWAIT);
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if (!desc)
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return NULL;
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desc->desc_num = num_periods;
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desc->direction = direction;
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desc->burst_size = burst_size;
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/* Build cyclic linked list */
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||
|
for (i = 0; i < num_periods; i++) {
|
||
|
struct ls2x_dma_sg *ldma_sg = &desc->sg[i];
|
||
|
|
||
|
/* Allocate DMA capable memory for hardware descriptor */
|
||
|
ldma_sg->hw = dma_pool_alloc(lchan->pool, GFP_NOWAIT, &ldma_sg->llp);
|
||
|
if (!ldma_sg->hw) {
|
||
|
desc->desc_num = i;
|
||
|
ls2x_dma_desc_free(&desc->vdesc);
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
ldma_sg->phys = buf_addr + period_len * i;
|
||
|
ldma_sg->len = period_len;
|
||
|
|
||
|
ls2x_dma_fill_desc(lchan, i, desc);
|
||
|
}
|
||
|
|
||
|
/* Lets make a cyclic list */
|
||
|
desc->sg[num_periods - 1].hw->ndesc_addr = desc->sg[0].llp | LDMA_DESC_EN;
|
||
|
desc->sg[num_periods - 1].hw->high_ndesc_addr = upper_32_bits(desc->sg[0].llp);
|
||
|
desc->cyclic = true;
|
||
|
desc->status = DMA_IN_PROGRESS;
|
||
|
|
||
|
return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ls2x_slave_config - set slave configuration for channel
|
||
|
* @chan: dma channel
|
||
|
* @cfg: slave configuration
|
||
|
*
|
||
|
* Sets slave configuration for channel
|
||
|
*/
|
||
|
static int ls2x_dma_slave_config(struct dma_chan *chan,
|
||
|
struct dma_slave_config *config)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
|
||
|
|
||
|
memcpy(&lchan->sconfig, config, sizeof(*config));
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ls2x_dma_issue_pending - push pending transactions to the hardware
|
||
|
* @chan: channel
|
||
|
*
|
||
|
* When this function is called, all pending transactions are pushed to the
|
||
|
* hardware and executed.
|
||
|
*/
|
||
|
static void ls2x_dma_issue_pending(struct dma_chan *chan)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
|
||
|
unsigned long flags;
|
||
|
|
||
|
spin_lock_irqsave(&lchan->vchan.lock, flags);
|
||
|
if (vchan_issue_pending(&lchan->vchan) && !lchan->desc)
|
||
|
ls2x_dma_start_transfer(lchan);
|
||
|
spin_unlock_irqrestore(&lchan->vchan.lock, flags);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ls2x_dma_terminate_all - terminate all transactions
|
||
|
* @chan: channel
|
||
|
*
|
||
|
* Stops all DMA transactions.
|
||
|
*/
|
||
|
static int ls2x_dma_terminate_all(struct dma_chan *chan)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
|
||
|
unsigned long flags;
|
||
|
LIST_HEAD(head);
|
||
|
|
||
|
spin_lock_irqsave(&lchan->vchan.lock, flags);
|
||
|
/* Setting stop cmd */
|
||
|
ls2x_dma_write_cmd(lchan, LDMA_STOP);
|
||
|
if (lchan->desc) {
|
||
|
vchan_terminate_vdesc(&lchan->desc->vdesc);
|
||
|
lchan->desc = NULL;
|
||
|
}
|
||
|
|
||
|
vchan_get_all_descriptors(&lchan->vchan, &head);
|
||
|
spin_unlock_irqrestore(&lchan->vchan.lock, flags);
|
||
|
|
||
|
vchan_dma_desc_free_list(&lchan->vchan, &head);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ls2x_dma_synchronize - Synchronizes the termination of transfers to the
|
||
|
* current context.
|
||
|
* @chan: channel
|
||
|
*/
|
||
|
static void ls2x_dma_synchronize(struct dma_chan *chan)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
|
||
|
|
||
|
vchan_synchronize(&lchan->vchan);
|
||
|
}
|
||
|
|
||
|
static int ls2x_dma_pause(struct dma_chan *chan)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
|
||
|
unsigned long flags;
|
||
|
|
||
|
spin_lock_irqsave(&lchan->vchan.lock, flags);
|
||
|
if (lchan->desc && lchan->desc->status == DMA_IN_PROGRESS) {
|
||
|
ls2x_dma_write_cmd(lchan, LDMA_STOP);
|
||
|
lchan->desc->status = DMA_PAUSED;
|
||
|
}
|
||
|
spin_unlock_irqrestore(&lchan->vchan.lock, flags);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int ls2x_dma_resume(struct dma_chan *chan)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = to_ldma_chan(chan);
|
||
|
unsigned long flags;
|
||
|
|
||
|
spin_lock_irqsave(&lchan->vchan.lock, flags);
|
||
|
if (lchan->desc && lchan->desc->status == DMA_PAUSED) {
|
||
|
lchan->desc->status = DMA_IN_PROGRESS;
|
||
|
ls2x_dma_write_cmd(lchan, LDMA_START);
|
||
|
}
|
||
|
spin_unlock_irqrestore(&lchan->vchan.lock, flags);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ls2x_dma_isr - LS2X DMA Interrupt handler
|
||
|
* @irq: IRQ number
|
||
|
* @dev_id: Pointer to ls2x_dma_chan
|
||
|
*
|
||
|
* Return: IRQ_HANDLED/IRQ_NONE
|
||
|
*/
|
||
|
static irqreturn_t ls2x_dma_isr(int irq, void *dev_id)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = dev_id;
|
||
|
struct ls2x_dma_desc *desc;
|
||
|
|
||
|
spin_lock(&lchan->vchan.lock);
|
||
|
desc = lchan->desc;
|
||
|
if (desc) {
|
||
|
if (desc->cyclic) {
|
||
|
vchan_cyclic_callback(&desc->vdesc);
|
||
|
} else {
|
||
|
desc->status = DMA_COMPLETE;
|
||
|
vchan_cookie_complete(&desc->vdesc);
|
||
|
ls2x_dma_start_transfer(lchan);
|
||
|
}
|
||
|
|
||
|
/* ls2x_dma_start_transfer() updates lchan->desc */
|
||
|
if (!lchan->desc)
|
||
|
ls2x_dma_write_cmd(lchan, LDMA_STOP);
|
||
|
}
|
||
|
spin_unlock(&lchan->vchan.lock);
|
||
|
|
||
|
return IRQ_HANDLED;
|
||
|
}
|
||
|
|
||
|
static int ls2x_dma_chan_init(struct platform_device *pdev,
|
||
|
struct ls2x_dma_priv *priv)
|
||
|
{
|
||
|
struct ls2x_dma_chan *lchan = &priv->lchan;
|
||
|
struct device *dev = &pdev->dev;
|
||
|
int ret;
|
||
|
|
||
|
lchan->irq = platform_get_irq(pdev, 0);
|
||
|
if (lchan->irq < 0)
|
||
|
return lchan->irq;
|
||
|
|
||
|
ret = devm_request_irq(dev, lchan->irq, ls2x_dma_isr, IRQF_TRIGGER_RISING,
|
||
|
dev_name(&pdev->dev), lchan);
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
/* Initialize channels related values */
|
||
|
INIT_LIST_HEAD(&priv->ddev.channels);
|
||
|
lchan->vchan.desc_free = ls2x_dma_desc_free;
|
||
|
vchan_init(&lchan->vchan, &priv->ddev);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ls2x_dma_probe - Driver probe function
|
||
|
* @pdev: Pointer to the platform_device structure
|
||
|
*
|
||
|
* Return: '0' on success and failure value on error
|
||
|
*/
|
||
|
static int ls2x_dma_probe(struct platform_device *pdev)
|
||
|
{
|
||
|
struct device *dev = &pdev->dev;
|
||
|
struct ls2x_dma_priv *priv;
|
||
|
struct dma_device *ddev;
|
||
|
int ret;
|
||
|
|
||
|
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
|
||
|
if (!priv)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
priv->regs = devm_platform_ioremap_resource(pdev, 0);
|
||
|
if (IS_ERR(priv->regs))
|
||
|
return dev_err_probe(dev, PTR_ERR(priv->regs),
|
||
|
"devm_platform_ioremap_resource failed.\n");
|
||
|
|
||
|
priv->dma_clk = devm_clk_get(&pdev->dev, NULL);
|
||
|
if (IS_ERR(priv->dma_clk))
|
||
|
return dev_err_probe(dev, PTR_ERR(priv->dma_clk), "devm_clk_get failed.\n");
|
||
|
|
||
|
ret = clk_prepare_enable(priv->dma_clk);
|
||
|
if (ret)
|
||
|
return dev_err_probe(dev, ret, "clk_prepare_enable failed.\n");
|
||
|
|
||
|
ret = ls2x_dma_chan_init(pdev, priv);
|
||
|
if (ret)
|
||
|
goto disable_clk;
|
||
|
|
||
|
ddev = &priv->ddev;
|
||
|
ddev->dev = dev;
|
||
|
dma_cap_zero(ddev->cap_mask);
|
||
|
dma_cap_set(DMA_SLAVE, ddev->cap_mask);
|
||
|
dma_cap_set(DMA_CYCLIC, ddev->cap_mask);
|
||
|
|
||
|
ddev->device_alloc_chan_resources = ls2x_dma_alloc_chan_resources;
|
||
|
ddev->device_free_chan_resources = ls2x_dma_free_chan_resources;
|
||
|
ddev->device_tx_status = dma_cookie_status;
|
||
|
ddev->device_issue_pending = ls2x_dma_issue_pending;
|
||
|
ddev->device_prep_slave_sg = ls2x_dma_prep_slave_sg;
|
||
|
ddev->device_prep_dma_cyclic = ls2x_dma_prep_dma_cyclic;
|
||
|
ddev->device_config = ls2x_dma_slave_config;
|
||
|
ddev->device_terminate_all = ls2x_dma_terminate_all;
|
||
|
ddev->device_synchronize = ls2x_dma_synchronize;
|
||
|
ddev->device_pause = ls2x_dma_pause;
|
||
|
ddev->device_resume = ls2x_dma_resume;
|
||
|
|
||
|
ddev->src_addr_widths = LDMA_SLAVE_BUSWIDTHS;
|
||
|
ddev->dst_addr_widths = LDMA_SLAVE_BUSWIDTHS;
|
||
|
ddev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
|
||
|
|
||
|
ret = dma_async_device_register(&priv->ddev);
|
||
|
if (ret < 0)
|
||
|
goto disable_clk;
|
||
|
|
||
|
ret = of_dma_controller_register(dev->of_node, of_dma_xlate_by_chan_id, priv);
|
||
|
if (ret < 0)
|
||
|
goto unregister_dmac;
|
||
|
|
||
|
platform_set_drvdata(pdev, priv);
|
||
|
|
||
|
dev_info(dev, "Loongson LS2X APB DMA driver registered successfully.\n");
|
||
|
return 0;
|
||
|
|
||
|
unregister_dmac:
|
||
|
dma_async_device_unregister(&priv->ddev);
|
||
|
disable_clk:
|
||
|
clk_disable_unprepare(priv->dma_clk);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ls2x_dma_remove - Driver remove function
|
||
|
* @pdev: Pointer to the platform_device structure
|
||
|
*/
|
||
|
static void ls2x_dma_remove(struct platform_device *pdev)
|
||
|
{
|
||
|
struct ls2x_dma_priv *priv = platform_get_drvdata(pdev);
|
||
|
|
||
|
of_dma_controller_free(pdev->dev.of_node);
|
||
|
dma_async_device_unregister(&priv->ddev);
|
||
|
clk_disable_unprepare(priv->dma_clk);
|
||
|
}
|
||
|
|
||
|
static const struct of_device_id ls2x_dma_of_match_table[] = {
|
||
|
{ .compatible = "loongson,ls2k1000-apbdma" },
|
||
|
{ /* sentinel */ }
|
||
|
};
|
||
|
MODULE_DEVICE_TABLE(of, ls2x_dma_of_match_table);
|
||
|
|
||
|
static struct platform_driver ls2x_dmac_driver = {
|
||
|
.probe = ls2x_dma_probe,
|
||
|
.remove_new = ls2x_dma_remove,
|
||
|
.driver = {
|
||
|
.name = "ls2x-apbdma",
|
||
|
.of_match_table = ls2x_dma_of_match_table,
|
||
|
},
|
||
|
};
|
||
|
module_platform_driver(ls2x_dmac_driver);
|
||
|
|
||
|
MODULE_DESCRIPTION("Loongson LS2X APB DMA Controller driver");
|
||
|
MODULE_AUTHOR("Loongson Technology Corporation Limited");
|
||
|
MODULE_LICENSE("GPL");
|