1436 строки
38 KiB
C
1436 строки
38 KiB
C
/*
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* S3C24XX DMA handling
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*
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* Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de>
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*
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* based on amba-pl08x.c
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*
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* Copyright (c) 2006 ARM Ltd.
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* Copyright (c) 2010 ST-Ericsson SA
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*
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* Author: Peter Pearse <peter.pearse@arm.com>
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* Author: Linus Walleij <linus.walleij@stericsson.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the Free
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* Software Foundation; either version 2 of the License, or (at your option)
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* any later version.
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*
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* The DMA controllers in S3C24XX SoCs have a varying number of DMA signals
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* that can be routed to any of the 4 to 8 hardware-channels.
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*
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* Therefore on these DMA controllers the number of channels
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* and the number of incoming DMA signals are two totally different things.
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* It is usually not possible to theoretically handle all physical signals,
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* so a multiplexing scheme with possible denial of use is necessary.
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*
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* Open items:
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* - bursts
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*/
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#include <linux/platform_device.h>
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#include <linux/types.h>
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#include <linux/dmaengine.h>
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#include <linux/dma-mapping.h>
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#include <linux/interrupt.h>
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#include <linux/clk.h>
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#include <linux/module.h>
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#include <linux/mod_devicetable.h>
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#include <linux/slab.h>
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#include <linux/platform_data/dma-s3c24xx.h>
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#include "dmaengine.h"
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#include "virt-dma.h"
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#define MAX_DMA_CHANNELS 8
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#define S3C24XX_DISRC 0x00
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#define S3C24XX_DISRCC 0x04
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#define S3C24XX_DISRCC_INC_INCREMENT 0
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#define S3C24XX_DISRCC_INC_FIXED BIT(0)
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#define S3C24XX_DISRCC_LOC_AHB 0
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#define S3C24XX_DISRCC_LOC_APB BIT(1)
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#define S3C24XX_DIDST 0x08
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#define S3C24XX_DIDSTC 0x0c
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#define S3C24XX_DIDSTC_INC_INCREMENT 0
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#define S3C24XX_DIDSTC_INC_FIXED BIT(0)
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#define S3C24XX_DIDSTC_LOC_AHB 0
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#define S3C24XX_DIDSTC_LOC_APB BIT(1)
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#define S3C24XX_DIDSTC_INT_TC0 0
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#define S3C24XX_DIDSTC_INT_RELOAD BIT(2)
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#define S3C24XX_DCON 0x10
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#define S3C24XX_DCON_TC_MASK 0xfffff
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#define S3C24XX_DCON_DSZ_BYTE (0 << 20)
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#define S3C24XX_DCON_DSZ_HALFWORD (1 << 20)
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#define S3C24XX_DCON_DSZ_WORD (2 << 20)
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#define S3C24XX_DCON_DSZ_MASK (3 << 20)
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#define S3C24XX_DCON_DSZ_SHIFT 20
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#define S3C24XX_DCON_AUTORELOAD 0
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#define S3C24XX_DCON_NORELOAD BIT(22)
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#define S3C24XX_DCON_HWTRIG BIT(23)
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#define S3C24XX_DCON_HWSRC_SHIFT 24
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#define S3C24XX_DCON_SERV_SINGLE 0
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#define S3C24XX_DCON_SERV_WHOLE BIT(27)
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#define S3C24XX_DCON_TSZ_UNIT 0
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#define S3C24XX_DCON_TSZ_BURST4 BIT(28)
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#define S3C24XX_DCON_INT BIT(29)
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#define S3C24XX_DCON_SYNC_PCLK 0
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#define S3C24XX_DCON_SYNC_HCLK BIT(30)
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#define S3C24XX_DCON_DEMAND 0
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#define S3C24XX_DCON_HANDSHAKE BIT(31)
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#define S3C24XX_DSTAT 0x14
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#define S3C24XX_DSTAT_STAT_BUSY BIT(20)
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#define S3C24XX_DSTAT_CURRTC_MASK 0xfffff
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#define S3C24XX_DMASKTRIG 0x20
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#define S3C24XX_DMASKTRIG_SWTRIG BIT(0)
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#define S3C24XX_DMASKTRIG_ON BIT(1)
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#define S3C24XX_DMASKTRIG_STOP BIT(2)
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#define S3C24XX_DMAREQSEL 0x24
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#define S3C24XX_DMAREQSEL_HW BIT(0)
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/*
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* S3C2410, S3C2440 and S3C2442 SoCs cannot select any physical channel
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* for a DMA source. Instead only specific channels are valid.
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* All of these SoCs have 4 physical channels and the number of request
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* source bits is 3. Additionally we also need 1 bit to mark the channel
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* as valid.
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* Therefore we separate the chansel element of the channel data into 4
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* parts of 4 bits each, to hold the information if the channel is valid
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* and the hw request source to use.
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*
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* Example:
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* SDI is valid on channels 0, 2 and 3 - with varying hw request sources.
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* For it the chansel field would look like
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*
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* ((BIT(3) | 1) << 3 * 4) | // channel 3, with request source 1
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* ((BIT(3) | 2) << 2 * 4) | // channel 2, with request source 2
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* ((BIT(3) | 2) << 0 * 4) // channel 0, with request source 2
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*/
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#define S3C24XX_CHANSEL_WIDTH 4
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#define S3C24XX_CHANSEL_VALID BIT(3)
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#define S3C24XX_CHANSEL_REQ_MASK 7
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/*
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* struct soc_data - vendor-specific config parameters for individual SoCs
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* @stride: spacing between the registers of each channel
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* @has_reqsel: does the controller use the newer requestselection mechanism
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* @has_clocks: are controllable dma-clocks present
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*/
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struct soc_data {
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int stride;
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bool has_reqsel;
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bool has_clocks;
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};
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/*
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* enum s3c24xx_dma_chan_state - holds the virtual channel states
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* @S3C24XX_DMA_CHAN_IDLE: the channel is idle
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* @S3C24XX_DMA_CHAN_RUNNING: the channel has allocated a physical transport
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* channel and is running a transfer on it
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* @S3C24XX_DMA_CHAN_WAITING: the channel is waiting for a physical transport
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* channel to become available (only pertains to memcpy channels)
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*/
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enum s3c24xx_dma_chan_state {
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S3C24XX_DMA_CHAN_IDLE,
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S3C24XX_DMA_CHAN_RUNNING,
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S3C24XX_DMA_CHAN_WAITING,
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};
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/*
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* struct s3c24xx_sg - structure containing data per sg
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* @src_addr: src address of sg
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* @dst_addr: dst address of sg
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* @len: transfer len in bytes
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* @node: node for txd's dsg_list
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*/
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struct s3c24xx_sg {
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dma_addr_t src_addr;
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dma_addr_t dst_addr;
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size_t len;
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struct list_head node;
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};
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/*
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* struct s3c24xx_txd - wrapper for struct dma_async_tx_descriptor
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* @vd: virtual DMA descriptor
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* @dsg_list: list of children sg's
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* @at: sg currently being transfered
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* @width: transfer width
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* @disrcc: value for source control register
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* @didstc: value for destination control register
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* @dcon: base value for dcon register
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* @cyclic: indicate cyclic transfer
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*/
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struct s3c24xx_txd {
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struct virt_dma_desc vd;
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struct list_head dsg_list;
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struct list_head *at;
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u8 width;
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u32 disrcc;
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u32 didstc;
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u32 dcon;
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bool cyclic;
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};
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struct s3c24xx_dma_chan;
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/*
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* struct s3c24xx_dma_phy - holder for the physical channels
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* @id: physical index to this channel
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* @valid: does the channel have all required elements
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* @base: virtual memory base (remapped) for the this channel
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* @irq: interrupt for this channel
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* @clk: clock for this channel
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* @lock: a lock to use when altering an instance of this struct
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* @serving: virtual channel currently being served by this physicalchannel
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* @host: a pointer to the host (internal use)
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*/
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struct s3c24xx_dma_phy {
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unsigned int id;
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bool valid;
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void __iomem *base;
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int irq;
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struct clk *clk;
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spinlock_t lock;
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struct s3c24xx_dma_chan *serving;
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struct s3c24xx_dma_engine *host;
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};
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/*
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* struct s3c24xx_dma_chan - this structure wraps a DMA ENGINE channel
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* @id: the id of the channel
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* @name: name of the channel
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* @vc: wrappped virtual channel
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* @phy: the physical channel utilized by this channel, if there is one
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* @runtime_addr: address for RX/TX according to the runtime config
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* @at: active transaction on this channel
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* @lock: a lock for this channel data
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* @host: a pointer to the host (internal use)
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* @state: whether the channel is idle, running etc
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* @slave: whether this channel is a device (slave) or for memcpy
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*/
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struct s3c24xx_dma_chan {
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int id;
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const char *name;
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struct virt_dma_chan vc;
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struct s3c24xx_dma_phy *phy;
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struct dma_slave_config cfg;
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struct s3c24xx_txd *at;
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struct s3c24xx_dma_engine *host;
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enum s3c24xx_dma_chan_state state;
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bool slave;
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};
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/*
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* struct s3c24xx_dma_engine - the local state holder for the S3C24XX
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* @pdev: the corresponding platform device
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* @pdata: platform data passed in from the platform/machine
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* @base: virtual memory base (remapped)
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* @slave: slave engine for this instance
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* @memcpy: memcpy engine for this instance
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* @phy_chans: array of data for the physical channels
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*/
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struct s3c24xx_dma_engine {
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struct platform_device *pdev;
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const struct s3c24xx_dma_platdata *pdata;
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struct soc_data *sdata;
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void __iomem *base;
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struct dma_device slave;
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struct dma_device memcpy;
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struct s3c24xx_dma_phy *phy_chans;
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};
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/*
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* Physical channel handling
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*/
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/*
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* Check whether a certain channel is busy or not.
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*/
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static int s3c24xx_dma_phy_busy(struct s3c24xx_dma_phy *phy)
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{
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unsigned int val = readl(phy->base + S3C24XX_DSTAT);
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return val & S3C24XX_DSTAT_STAT_BUSY;
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}
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static bool s3c24xx_dma_phy_valid(struct s3c24xx_dma_chan *s3cchan,
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struct s3c24xx_dma_phy *phy)
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{
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struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
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const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
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struct s3c24xx_dma_channel *cdata = &pdata->channels[s3cchan->id];
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int phyvalid;
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/* every phy is valid for memcopy channels */
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if (!s3cchan->slave)
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return true;
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/* On newer variants all phys can be used for all virtual channels */
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if (s3cdma->sdata->has_reqsel)
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return true;
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phyvalid = (cdata->chansel >> (phy->id * S3C24XX_CHANSEL_WIDTH));
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return (phyvalid & S3C24XX_CHANSEL_VALID) ? true : false;
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}
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/*
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* Allocate a physical channel for a virtual channel
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*
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* Try to locate a physical channel to be used for this transfer. If all
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* are taken return NULL and the requester will have to cope by using
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* some fallback PIO mode or retrying later.
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*/
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static
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struct s3c24xx_dma_phy *s3c24xx_dma_get_phy(struct s3c24xx_dma_chan *s3cchan)
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{
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struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
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struct s3c24xx_dma_phy *phy = NULL;
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unsigned long flags;
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int i;
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int ret;
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for (i = 0; i < s3cdma->pdata->num_phy_channels; i++) {
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phy = &s3cdma->phy_chans[i];
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if (!phy->valid)
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continue;
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if (!s3c24xx_dma_phy_valid(s3cchan, phy))
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continue;
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spin_lock_irqsave(&phy->lock, flags);
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if (!phy->serving) {
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phy->serving = s3cchan;
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spin_unlock_irqrestore(&phy->lock, flags);
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break;
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}
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spin_unlock_irqrestore(&phy->lock, flags);
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}
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/* No physical channel available, cope with it */
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if (i == s3cdma->pdata->num_phy_channels) {
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dev_warn(&s3cdma->pdev->dev, "no phy channel available\n");
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return NULL;
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}
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/* start the phy clock */
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if (s3cdma->sdata->has_clocks) {
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ret = clk_enable(phy->clk);
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if (ret) {
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dev_err(&s3cdma->pdev->dev, "could not enable clock for channel %d, err %d\n",
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phy->id, ret);
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phy->serving = NULL;
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return NULL;
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}
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}
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return phy;
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}
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/*
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* Mark the physical channel as free.
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*
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* This drops the link between the physical and virtual channel.
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*/
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static inline void s3c24xx_dma_put_phy(struct s3c24xx_dma_phy *phy)
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{
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struct s3c24xx_dma_engine *s3cdma = phy->host;
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if (s3cdma->sdata->has_clocks)
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clk_disable(phy->clk);
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phy->serving = NULL;
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}
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/*
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* Stops the channel by writing the stop bit.
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* This should not be used for an on-going transfer, but as a method of
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* shutting down a channel (eg, when it's no longer used) or terminating a
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* transfer.
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*/
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static void s3c24xx_dma_terminate_phy(struct s3c24xx_dma_phy *phy)
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{
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writel(S3C24XX_DMASKTRIG_STOP, phy->base + S3C24XX_DMASKTRIG);
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}
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/*
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* Virtual channel handling
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*/
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static inline
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struct s3c24xx_dma_chan *to_s3c24xx_dma_chan(struct dma_chan *chan)
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{
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return container_of(chan, struct s3c24xx_dma_chan, vc.chan);
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}
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static u32 s3c24xx_dma_getbytes_chan(struct s3c24xx_dma_chan *s3cchan)
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{
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struct s3c24xx_dma_phy *phy = s3cchan->phy;
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struct s3c24xx_txd *txd = s3cchan->at;
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u32 tc = readl(phy->base + S3C24XX_DSTAT) & S3C24XX_DSTAT_CURRTC_MASK;
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return tc * txd->width;
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}
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static int s3c24xx_dma_set_runtime_config(struct dma_chan *chan,
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struct dma_slave_config *config)
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{
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struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
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unsigned long flags;
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int ret = 0;
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/* Reject definitely invalid configurations */
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if (config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
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config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
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return -EINVAL;
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spin_lock_irqsave(&s3cchan->vc.lock, flags);
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if (!s3cchan->slave) {
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ret = -EINVAL;
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goto out;
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}
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s3cchan->cfg = *config;
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out:
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spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
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return ret;
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}
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/*
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* Transfer handling
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*/
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static inline
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struct s3c24xx_txd *to_s3c24xx_txd(struct dma_async_tx_descriptor *tx)
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{
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return container_of(tx, struct s3c24xx_txd, vd.tx);
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}
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static struct s3c24xx_txd *s3c24xx_dma_get_txd(void)
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{
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struct s3c24xx_txd *txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
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if (txd) {
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INIT_LIST_HEAD(&txd->dsg_list);
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txd->dcon = S3C24XX_DCON_INT | S3C24XX_DCON_NORELOAD;
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}
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return txd;
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}
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static void s3c24xx_dma_free_txd(struct s3c24xx_txd *txd)
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{
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struct s3c24xx_sg *dsg, *_dsg;
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list_for_each_entry_safe(dsg, _dsg, &txd->dsg_list, node) {
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list_del(&dsg->node);
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kfree(dsg);
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}
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kfree(txd);
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}
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static void s3c24xx_dma_start_next_sg(struct s3c24xx_dma_chan *s3cchan,
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struct s3c24xx_txd *txd)
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{
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struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
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struct s3c24xx_dma_phy *phy = s3cchan->phy;
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const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
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struct s3c24xx_sg *dsg = list_entry(txd->at, struct s3c24xx_sg, node);
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u32 dcon = txd->dcon;
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u32 val;
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/* transfer-size and -count from len and width */
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switch (txd->width) {
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case 1:
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dcon |= S3C24XX_DCON_DSZ_BYTE | dsg->len;
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break;
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case 2:
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dcon |= S3C24XX_DCON_DSZ_HALFWORD | (dsg->len / 2);
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break;
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case 4:
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dcon |= S3C24XX_DCON_DSZ_WORD | (dsg->len / 4);
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break;
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}
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if (s3cchan->slave) {
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struct s3c24xx_dma_channel *cdata =
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&pdata->channels[s3cchan->id];
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if (s3cdma->sdata->has_reqsel) {
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writel_relaxed((cdata->chansel << 1) |
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S3C24XX_DMAREQSEL_HW,
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phy->base + S3C24XX_DMAREQSEL);
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} else {
|
|
int csel = cdata->chansel >> (phy->id *
|
|
S3C24XX_CHANSEL_WIDTH);
|
|
|
|
csel &= S3C24XX_CHANSEL_REQ_MASK;
|
|
dcon |= csel << S3C24XX_DCON_HWSRC_SHIFT;
|
|
dcon |= S3C24XX_DCON_HWTRIG;
|
|
}
|
|
} else {
|
|
if (s3cdma->sdata->has_reqsel)
|
|
writel_relaxed(0, phy->base + S3C24XX_DMAREQSEL);
|
|
}
|
|
|
|
writel_relaxed(dsg->src_addr, phy->base + S3C24XX_DISRC);
|
|
writel_relaxed(txd->disrcc, phy->base + S3C24XX_DISRCC);
|
|
writel_relaxed(dsg->dst_addr, phy->base + S3C24XX_DIDST);
|
|
writel_relaxed(txd->didstc, phy->base + S3C24XX_DIDSTC);
|
|
writel_relaxed(dcon, phy->base + S3C24XX_DCON);
|
|
|
|
val = readl_relaxed(phy->base + S3C24XX_DMASKTRIG);
|
|
val &= ~S3C24XX_DMASKTRIG_STOP;
|
|
val |= S3C24XX_DMASKTRIG_ON;
|
|
|
|
/* trigger the dma operation for memcpy transfers */
|
|
if (!s3cchan->slave)
|
|
val |= S3C24XX_DMASKTRIG_SWTRIG;
|
|
|
|
writel(val, phy->base + S3C24XX_DMASKTRIG);
|
|
}
|
|
|
|
/*
|
|
* Set the initial DMA register values and start first sg.
|
|
*/
|
|
static void s3c24xx_dma_start_next_txd(struct s3c24xx_dma_chan *s3cchan)
|
|
{
|
|
struct s3c24xx_dma_phy *phy = s3cchan->phy;
|
|
struct virt_dma_desc *vd = vchan_next_desc(&s3cchan->vc);
|
|
struct s3c24xx_txd *txd = to_s3c24xx_txd(&vd->tx);
|
|
|
|
list_del(&txd->vd.node);
|
|
|
|
s3cchan->at = txd;
|
|
|
|
/* Wait for channel inactive */
|
|
while (s3c24xx_dma_phy_busy(phy))
|
|
cpu_relax();
|
|
|
|
/* point to the first element of the sg list */
|
|
txd->at = txd->dsg_list.next;
|
|
s3c24xx_dma_start_next_sg(s3cchan, txd);
|
|
}
|
|
|
|
static void s3c24xx_dma_free_txd_list(struct s3c24xx_dma_engine *s3cdma,
|
|
struct s3c24xx_dma_chan *s3cchan)
|
|
{
|
|
LIST_HEAD(head);
|
|
|
|
vchan_get_all_descriptors(&s3cchan->vc, &head);
|
|
vchan_dma_desc_free_list(&s3cchan->vc, &head);
|
|
}
|
|
|
|
/*
|
|
* Try to allocate a physical channel. When successful, assign it to
|
|
* this virtual channel, and initiate the next descriptor. The
|
|
* virtual channel lock must be held at this point.
|
|
*/
|
|
static void s3c24xx_dma_phy_alloc_and_start(struct s3c24xx_dma_chan *s3cchan)
|
|
{
|
|
struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
|
|
struct s3c24xx_dma_phy *phy;
|
|
|
|
phy = s3c24xx_dma_get_phy(s3cchan);
|
|
if (!phy) {
|
|
dev_dbg(&s3cdma->pdev->dev, "no physical channel available for xfer on %s\n",
|
|
s3cchan->name);
|
|
s3cchan->state = S3C24XX_DMA_CHAN_WAITING;
|
|
return;
|
|
}
|
|
|
|
dev_dbg(&s3cdma->pdev->dev, "allocated physical channel %d for xfer on %s\n",
|
|
phy->id, s3cchan->name);
|
|
|
|
s3cchan->phy = phy;
|
|
s3cchan->state = S3C24XX_DMA_CHAN_RUNNING;
|
|
|
|
s3c24xx_dma_start_next_txd(s3cchan);
|
|
}
|
|
|
|
static void s3c24xx_dma_phy_reassign_start(struct s3c24xx_dma_phy *phy,
|
|
struct s3c24xx_dma_chan *s3cchan)
|
|
{
|
|
struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
|
|
|
|
dev_dbg(&s3cdma->pdev->dev, "reassigned physical channel %d for xfer on %s\n",
|
|
phy->id, s3cchan->name);
|
|
|
|
/*
|
|
* We do this without taking the lock; we're really only concerned
|
|
* about whether this pointer is NULL or not, and we're guaranteed
|
|
* that this will only be called when it _already_ is non-NULL.
|
|
*/
|
|
phy->serving = s3cchan;
|
|
s3cchan->phy = phy;
|
|
s3cchan->state = S3C24XX_DMA_CHAN_RUNNING;
|
|
s3c24xx_dma_start_next_txd(s3cchan);
|
|
}
|
|
|
|
/*
|
|
* Free a physical DMA channel, potentially reallocating it to another
|
|
* virtual channel if we have any pending.
|
|
*/
|
|
static void s3c24xx_dma_phy_free(struct s3c24xx_dma_chan *s3cchan)
|
|
{
|
|
struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
|
|
struct s3c24xx_dma_chan *p, *next;
|
|
|
|
retry:
|
|
next = NULL;
|
|
|
|
/* Find a waiting virtual channel for the next transfer. */
|
|
list_for_each_entry(p, &s3cdma->memcpy.channels, vc.chan.device_node)
|
|
if (p->state == S3C24XX_DMA_CHAN_WAITING) {
|
|
next = p;
|
|
break;
|
|
}
|
|
|
|
if (!next) {
|
|
list_for_each_entry(p, &s3cdma->slave.channels,
|
|
vc.chan.device_node)
|
|
if (p->state == S3C24XX_DMA_CHAN_WAITING &&
|
|
s3c24xx_dma_phy_valid(p, s3cchan->phy)) {
|
|
next = p;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Ensure that the physical channel is stopped */
|
|
s3c24xx_dma_terminate_phy(s3cchan->phy);
|
|
|
|
if (next) {
|
|
bool success;
|
|
|
|
/*
|
|
* Eww. We know this isn't going to deadlock
|
|
* but lockdep probably doesn't.
|
|
*/
|
|
spin_lock(&next->vc.lock);
|
|
/* Re-check the state now that we have the lock */
|
|
success = next->state == S3C24XX_DMA_CHAN_WAITING;
|
|
if (success)
|
|
s3c24xx_dma_phy_reassign_start(s3cchan->phy, next);
|
|
spin_unlock(&next->vc.lock);
|
|
|
|
/* If the state changed, try to find another channel */
|
|
if (!success)
|
|
goto retry;
|
|
} else {
|
|
/* No more jobs, so free up the physical channel */
|
|
s3c24xx_dma_put_phy(s3cchan->phy);
|
|
}
|
|
|
|
s3cchan->phy = NULL;
|
|
s3cchan->state = S3C24XX_DMA_CHAN_IDLE;
|
|
}
|
|
|
|
static void s3c24xx_dma_desc_free(struct virt_dma_desc *vd)
|
|
{
|
|
struct s3c24xx_txd *txd = to_s3c24xx_txd(&vd->tx);
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(vd->tx.chan);
|
|
|
|
if (!s3cchan->slave)
|
|
dma_descriptor_unmap(&vd->tx);
|
|
|
|
s3c24xx_dma_free_txd(txd);
|
|
}
|
|
|
|
static irqreturn_t s3c24xx_dma_irq(int irq, void *data)
|
|
{
|
|
struct s3c24xx_dma_phy *phy = data;
|
|
struct s3c24xx_dma_chan *s3cchan = phy->serving;
|
|
struct s3c24xx_txd *txd;
|
|
|
|
dev_dbg(&phy->host->pdev->dev, "interrupt on channel %d\n", phy->id);
|
|
|
|
/*
|
|
* Interrupts happen to notify the completion of a transfer and the
|
|
* channel should have moved into its stop state already on its own.
|
|
* Therefore interrupts on channels not bound to a virtual channel
|
|
* should never happen. Nevertheless send a terminate command to the
|
|
* channel if the unlikely case happens.
|
|
*/
|
|
if (unlikely(!s3cchan)) {
|
|
dev_err(&phy->host->pdev->dev, "interrupt on unused channel %d\n",
|
|
phy->id);
|
|
|
|
s3c24xx_dma_terminate_phy(phy);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
spin_lock(&s3cchan->vc.lock);
|
|
txd = s3cchan->at;
|
|
if (txd) {
|
|
/* when more sg's are in this txd, start the next one */
|
|
if (!list_is_last(txd->at, &txd->dsg_list)) {
|
|
txd->at = txd->at->next;
|
|
if (txd->cyclic)
|
|
vchan_cyclic_callback(&txd->vd);
|
|
s3c24xx_dma_start_next_sg(s3cchan, txd);
|
|
} else if (!txd->cyclic) {
|
|
s3cchan->at = NULL;
|
|
vchan_cookie_complete(&txd->vd);
|
|
|
|
/*
|
|
* And start the next descriptor (if any),
|
|
* otherwise free this channel.
|
|
*/
|
|
if (vchan_next_desc(&s3cchan->vc))
|
|
s3c24xx_dma_start_next_txd(s3cchan);
|
|
else
|
|
s3c24xx_dma_phy_free(s3cchan);
|
|
} else {
|
|
vchan_cyclic_callback(&txd->vd);
|
|
|
|
/* Cyclic: reset at beginning */
|
|
txd->at = txd->dsg_list.next;
|
|
s3c24xx_dma_start_next_sg(s3cchan, txd);
|
|
}
|
|
}
|
|
spin_unlock(&s3cchan->vc.lock);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* The DMA ENGINE API
|
|
*/
|
|
|
|
static int s3c24xx_dma_terminate_all(struct dma_chan *chan)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
|
|
struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
|
|
unsigned long flags;
|
|
int ret = 0;
|
|
|
|
spin_lock_irqsave(&s3cchan->vc.lock, flags);
|
|
|
|
if (!s3cchan->phy && !s3cchan->at) {
|
|
dev_err(&s3cdma->pdev->dev, "trying to terminate already stopped channel %d\n",
|
|
s3cchan->id);
|
|
ret = -EINVAL;
|
|
goto unlock;
|
|
}
|
|
|
|
s3cchan->state = S3C24XX_DMA_CHAN_IDLE;
|
|
|
|
/* Mark physical channel as free */
|
|
if (s3cchan->phy)
|
|
s3c24xx_dma_phy_free(s3cchan);
|
|
|
|
/* Dequeue current job */
|
|
if (s3cchan->at) {
|
|
vchan_terminate_vdesc(&s3cchan->at->vd);
|
|
s3cchan->at = NULL;
|
|
}
|
|
|
|
/* Dequeue jobs not yet fired as well */
|
|
s3c24xx_dma_free_txd_list(s3cdma, s3cchan);
|
|
unlock:
|
|
spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void s3c24xx_dma_synchronize(struct dma_chan *chan)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
|
|
|
|
vchan_synchronize(&s3cchan->vc);
|
|
}
|
|
|
|
static void s3c24xx_dma_free_chan_resources(struct dma_chan *chan)
|
|
{
|
|
/* Ensure all queued descriptors are freed */
|
|
vchan_free_chan_resources(to_virt_chan(chan));
|
|
}
|
|
|
|
static enum dma_status s3c24xx_dma_tx_status(struct dma_chan *chan,
|
|
dma_cookie_t cookie, struct dma_tx_state *txstate)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
|
|
struct s3c24xx_txd *txd;
|
|
struct s3c24xx_sg *dsg;
|
|
struct virt_dma_desc *vd;
|
|
unsigned long flags;
|
|
enum dma_status ret;
|
|
size_t bytes = 0;
|
|
|
|
spin_lock_irqsave(&s3cchan->vc.lock, flags);
|
|
ret = dma_cookie_status(chan, cookie, txstate);
|
|
|
|
/*
|
|
* There's no point calculating the residue if there's
|
|
* no txstate to store the value.
|
|
*/
|
|
if (ret == DMA_COMPLETE || !txstate) {
|
|
spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
|
|
return ret;
|
|
}
|
|
|
|
vd = vchan_find_desc(&s3cchan->vc, cookie);
|
|
if (vd) {
|
|
/* On the issued list, so hasn't been processed yet */
|
|
txd = to_s3c24xx_txd(&vd->tx);
|
|
|
|
list_for_each_entry(dsg, &txd->dsg_list, node)
|
|
bytes += dsg->len;
|
|
} else {
|
|
/*
|
|
* Currently running, so sum over the pending sg's and
|
|
* the currently active one.
|
|
*/
|
|
txd = s3cchan->at;
|
|
|
|
dsg = list_entry(txd->at, struct s3c24xx_sg, node);
|
|
list_for_each_entry_from(dsg, &txd->dsg_list, node)
|
|
bytes += dsg->len;
|
|
|
|
bytes += s3c24xx_dma_getbytes_chan(s3cchan);
|
|
}
|
|
spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
|
|
|
|
/*
|
|
* This cookie not complete yet
|
|
* Get number of bytes left in the active transactions and queue
|
|
*/
|
|
dma_set_residue(txstate, bytes);
|
|
|
|
/* Whether waiting or running, we're in progress */
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Initialize a descriptor to be used by memcpy submit
|
|
*/
|
|
static struct dma_async_tx_descriptor *s3c24xx_dma_prep_memcpy(
|
|
struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
|
|
size_t len, unsigned long flags)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
|
|
struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
|
|
struct s3c24xx_txd *txd;
|
|
struct s3c24xx_sg *dsg;
|
|
int src_mod, dest_mod;
|
|
|
|
dev_dbg(&s3cdma->pdev->dev, "prepare memcpy of %zu bytes from %s\n",
|
|
len, s3cchan->name);
|
|
|
|
if ((len & S3C24XX_DCON_TC_MASK) != len) {
|
|
dev_err(&s3cdma->pdev->dev, "memcpy size %zu to large\n", len);
|
|
return NULL;
|
|
}
|
|
|
|
txd = s3c24xx_dma_get_txd();
|
|
if (!txd)
|
|
return NULL;
|
|
|
|
dsg = kzalloc(sizeof(*dsg), GFP_NOWAIT);
|
|
if (!dsg) {
|
|
s3c24xx_dma_free_txd(txd);
|
|
return NULL;
|
|
}
|
|
list_add_tail(&dsg->node, &txd->dsg_list);
|
|
|
|
dsg->src_addr = src;
|
|
dsg->dst_addr = dest;
|
|
dsg->len = len;
|
|
|
|
/*
|
|
* Determine a suitable transfer width.
|
|
* The DMA controller cannot fetch/store information which is not
|
|
* naturally aligned on the bus, i.e., a 4 byte fetch must start at
|
|
* an address divisible by 4 - more generally addr % width must be 0.
|
|
*/
|
|
src_mod = src % 4;
|
|
dest_mod = dest % 4;
|
|
switch (len % 4) {
|
|
case 0:
|
|
txd->width = (src_mod == 0 && dest_mod == 0) ? 4 : 1;
|
|
break;
|
|
case 2:
|
|
txd->width = ((src_mod == 2 || src_mod == 0) &&
|
|
(dest_mod == 2 || dest_mod == 0)) ? 2 : 1;
|
|
break;
|
|
default:
|
|
txd->width = 1;
|
|
break;
|
|
}
|
|
|
|
txd->disrcc = S3C24XX_DISRCC_LOC_AHB | S3C24XX_DISRCC_INC_INCREMENT;
|
|
txd->didstc = S3C24XX_DIDSTC_LOC_AHB | S3C24XX_DIDSTC_INC_INCREMENT;
|
|
txd->dcon |= S3C24XX_DCON_DEMAND | S3C24XX_DCON_SYNC_HCLK |
|
|
S3C24XX_DCON_SERV_WHOLE;
|
|
|
|
return vchan_tx_prep(&s3cchan->vc, &txd->vd, flags);
|
|
}
|
|
|
|
static struct dma_async_tx_descriptor *s3c24xx_dma_prep_dma_cyclic(
|
|
struct dma_chan *chan, dma_addr_t addr, size_t size, size_t period,
|
|
enum dma_transfer_direction direction, unsigned long flags)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
|
|
struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
|
|
const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
|
|
struct s3c24xx_dma_channel *cdata = &pdata->channels[s3cchan->id];
|
|
struct s3c24xx_txd *txd;
|
|
struct s3c24xx_sg *dsg;
|
|
unsigned sg_len;
|
|
dma_addr_t slave_addr;
|
|
u32 hwcfg = 0;
|
|
int i;
|
|
|
|
dev_dbg(&s3cdma->pdev->dev,
|
|
"prepare cyclic transaction of %zu bytes with period %zu from %s\n",
|
|
size, period, s3cchan->name);
|
|
|
|
if (!is_slave_direction(direction)) {
|
|
dev_err(&s3cdma->pdev->dev,
|
|
"direction %d unsupported\n", direction);
|
|
return NULL;
|
|
}
|
|
|
|
txd = s3c24xx_dma_get_txd();
|
|
if (!txd)
|
|
return NULL;
|
|
|
|
txd->cyclic = 1;
|
|
|
|
if (cdata->handshake)
|
|
txd->dcon |= S3C24XX_DCON_HANDSHAKE;
|
|
|
|
switch (cdata->bus) {
|
|
case S3C24XX_DMA_APB:
|
|
txd->dcon |= S3C24XX_DCON_SYNC_PCLK;
|
|
hwcfg |= S3C24XX_DISRCC_LOC_APB;
|
|
break;
|
|
case S3C24XX_DMA_AHB:
|
|
txd->dcon |= S3C24XX_DCON_SYNC_HCLK;
|
|
hwcfg |= S3C24XX_DISRCC_LOC_AHB;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Always assume our peripheral desintation is a fixed
|
|
* address in memory.
|
|
*/
|
|
hwcfg |= S3C24XX_DISRCC_INC_FIXED;
|
|
|
|
/*
|
|
* Individual dma operations are requested by the slave,
|
|
* so serve only single atomic operations (S3C24XX_DCON_SERV_SINGLE).
|
|
*/
|
|
txd->dcon |= S3C24XX_DCON_SERV_SINGLE;
|
|
|
|
if (direction == DMA_MEM_TO_DEV) {
|
|
txd->disrcc = S3C24XX_DISRCC_LOC_AHB |
|
|
S3C24XX_DISRCC_INC_INCREMENT;
|
|
txd->didstc = hwcfg;
|
|
slave_addr = s3cchan->cfg.dst_addr;
|
|
txd->width = s3cchan->cfg.dst_addr_width;
|
|
} else {
|
|
txd->disrcc = hwcfg;
|
|
txd->didstc = S3C24XX_DIDSTC_LOC_AHB |
|
|
S3C24XX_DIDSTC_INC_INCREMENT;
|
|
slave_addr = s3cchan->cfg.src_addr;
|
|
txd->width = s3cchan->cfg.src_addr_width;
|
|
}
|
|
|
|
sg_len = size / period;
|
|
|
|
for (i = 0; i < sg_len; i++) {
|
|
dsg = kzalloc(sizeof(*dsg), GFP_NOWAIT);
|
|
if (!dsg) {
|
|
s3c24xx_dma_free_txd(txd);
|
|
return NULL;
|
|
}
|
|
list_add_tail(&dsg->node, &txd->dsg_list);
|
|
|
|
dsg->len = period;
|
|
/* Check last period length */
|
|
if (i == sg_len - 1)
|
|
dsg->len = size - period * i;
|
|
if (direction == DMA_MEM_TO_DEV) {
|
|
dsg->src_addr = addr + period * i;
|
|
dsg->dst_addr = slave_addr;
|
|
} else { /* DMA_DEV_TO_MEM */
|
|
dsg->src_addr = slave_addr;
|
|
dsg->dst_addr = addr + period * i;
|
|
}
|
|
}
|
|
|
|
return vchan_tx_prep(&s3cchan->vc, &txd->vd, flags);
|
|
}
|
|
|
|
static struct dma_async_tx_descriptor *s3c24xx_dma_prep_slave_sg(
|
|
struct dma_chan *chan, struct scatterlist *sgl,
|
|
unsigned int sg_len, enum dma_transfer_direction direction,
|
|
unsigned long flags, void *context)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
|
|
struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
|
|
const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
|
|
struct s3c24xx_dma_channel *cdata = &pdata->channels[s3cchan->id];
|
|
struct s3c24xx_txd *txd;
|
|
struct s3c24xx_sg *dsg;
|
|
struct scatterlist *sg;
|
|
dma_addr_t slave_addr;
|
|
u32 hwcfg = 0;
|
|
int tmp;
|
|
|
|
dev_dbg(&s3cdma->pdev->dev, "prepare transaction of %d bytes from %s\n",
|
|
sg_dma_len(sgl), s3cchan->name);
|
|
|
|
txd = s3c24xx_dma_get_txd();
|
|
if (!txd)
|
|
return NULL;
|
|
|
|
if (cdata->handshake)
|
|
txd->dcon |= S3C24XX_DCON_HANDSHAKE;
|
|
|
|
switch (cdata->bus) {
|
|
case S3C24XX_DMA_APB:
|
|
txd->dcon |= S3C24XX_DCON_SYNC_PCLK;
|
|
hwcfg |= S3C24XX_DISRCC_LOC_APB;
|
|
break;
|
|
case S3C24XX_DMA_AHB:
|
|
txd->dcon |= S3C24XX_DCON_SYNC_HCLK;
|
|
hwcfg |= S3C24XX_DISRCC_LOC_AHB;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Always assume our peripheral desintation is a fixed
|
|
* address in memory.
|
|
*/
|
|
hwcfg |= S3C24XX_DISRCC_INC_FIXED;
|
|
|
|
/*
|
|
* Individual dma operations are requested by the slave,
|
|
* so serve only single atomic operations (S3C24XX_DCON_SERV_SINGLE).
|
|
*/
|
|
txd->dcon |= S3C24XX_DCON_SERV_SINGLE;
|
|
|
|
if (direction == DMA_MEM_TO_DEV) {
|
|
txd->disrcc = S3C24XX_DISRCC_LOC_AHB |
|
|
S3C24XX_DISRCC_INC_INCREMENT;
|
|
txd->didstc = hwcfg;
|
|
slave_addr = s3cchan->cfg.dst_addr;
|
|
txd->width = s3cchan->cfg.dst_addr_width;
|
|
} else if (direction == DMA_DEV_TO_MEM) {
|
|
txd->disrcc = hwcfg;
|
|
txd->didstc = S3C24XX_DIDSTC_LOC_AHB |
|
|
S3C24XX_DIDSTC_INC_INCREMENT;
|
|
slave_addr = s3cchan->cfg.src_addr;
|
|
txd->width = s3cchan->cfg.src_addr_width;
|
|
} else {
|
|
s3c24xx_dma_free_txd(txd);
|
|
dev_err(&s3cdma->pdev->dev,
|
|
"direction %d unsupported\n", direction);
|
|
return NULL;
|
|
}
|
|
|
|
for_each_sg(sgl, sg, sg_len, tmp) {
|
|
dsg = kzalloc(sizeof(*dsg), GFP_NOWAIT);
|
|
if (!dsg) {
|
|
s3c24xx_dma_free_txd(txd);
|
|
return NULL;
|
|
}
|
|
list_add_tail(&dsg->node, &txd->dsg_list);
|
|
|
|
dsg->len = sg_dma_len(sg);
|
|
if (direction == DMA_MEM_TO_DEV) {
|
|
dsg->src_addr = sg_dma_address(sg);
|
|
dsg->dst_addr = slave_addr;
|
|
} else { /* DMA_DEV_TO_MEM */
|
|
dsg->src_addr = slave_addr;
|
|
dsg->dst_addr = sg_dma_address(sg);
|
|
}
|
|
}
|
|
|
|
return vchan_tx_prep(&s3cchan->vc, &txd->vd, flags);
|
|
}
|
|
|
|
/*
|
|
* Slave transactions callback to the slave device to allow
|
|
* synchronization of slave DMA signals with the DMAC enable
|
|
*/
|
|
static void s3c24xx_dma_issue_pending(struct dma_chan *chan)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&s3cchan->vc.lock, flags);
|
|
if (vchan_issue_pending(&s3cchan->vc)) {
|
|
if (!s3cchan->phy && s3cchan->state != S3C24XX_DMA_CHAN_WAITING)
|
|
s3c24xx_dma_phy_alloc_and_start(s3cchan);
|
|
}
|
|
spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
|
|
}
|
|
|
|
/*
|
|
* Bringup and teardown
|
|
*/
|
|
|
|
/*
|
|
* Initialise the DMAC memcpy/slave channels.
|
|
* Make a local wrapper to hold required data
|
|
*/
|
|
static int s3c24xx_dma_init_virtual_channels(struct s3c24xx_dma_engine *s3cdma,
|
|
struct dma_device *dmadev, unsigned int channels, bool slave)
|
|
{
|
|
struct s3c24xx_dma_chan *chan;
|
|
int i;
|
|
|
|
INIT_LIST_HEAD(&dmadev->channels);
|
|
|
|
/*
|
|
* Register as many many memcpy as we have physical channels,
|
|
* we won't always be able to use all but the code will have
|
|
* to cope with that situation.
|
|
*/
|
|
for (i = 0; i < channels; i++) {
|
|
chan = devm_kzalloc(dmadev->dev, sizeof(*chan), GFP_KERNEL);
|
|
if (!chan)
|
|
return -ENOMEM;
|
|
|
|
chan->id = i;
|
|
chan->host = s3cdma;
|
|
chan->state = S3C24XX_DMA_CHAN_IDLE;
|
|
|
|
if (slave) {
|
|
chan->slave = true;
|
|
chan->name = kasprintf(GFP_KERNEL, "slave%d", i);
|
|
if (!chan->name)
|
|
return -ENOMEM;
|
|
} else {
|
|
chan->name = kasprintf(GFP_KERNEL, "memcpy%d", i);
|
|
if (!chan->name)
|
|
return -ENOMEM;
|
|
}
|
|
dev_dbg(dmadev->dev,
|
|
"initialize virtual channel \"%s\"\n",
|
|
chan->name);
|
|
|
|
chan->vc.desc_free = s3c24xx_dma_desc_free;
|
|
vchan_init(&chan->vc, dmadev);
|
|
}
|
|
dev_info(dmadev->dev, "initialized %d virtual %s channels\n",
|
|
i, slave ? "slave" : "memcpy");
|
|
return i;
|
|
}
|
|
|
|
static void s3c24xx_dma_free_virtual_channels(struct dma_device *dmadev)
|
|
{
|
|
struct s3c24xx_dma_chan *chan = NULL;
|
|
struct s3c24xx_dma_chan *next;
|
|
|
|
list_for_each_entry_safe(chan,
|
|
next, &dmadev->channels, vc.chan.device_node) {
|
|
list_del(&chan->vc.chan.device_node);
|
|
tasklet_kill(&chan->vc.task);
|
|
}
|
|
}
|
|
|
|
/* s3c2410, s3c2440 and s3c2442 have a 0x40 stride without separate clocks */
|
|
static struct soc_data soc_s3c2410 = {
|
|
.stride = 0x40,
|
|
.has_reqsel = false,
|
|
.has_clocks = false,
|
|
};
|
|
|
|
/* s3c2412 and s3c2413 have a 0x40 stride and dmareqsel mechanism */
|
|
static struct soc_data soc_s3c2412 = {
|
|
.stride = 0x40,
|
|
.has_reqsel = true,
|
|
.has_clocks = true,
|
|
};
|
|
|
|
/* s3c2443 and following have a 0x100 stride and dmareqsel mechanism */
|
|
static struct soc_data soc_s3c2443 = {
|
|
.stride = 0x100,
|
|
.has_reqsel = true,
|
|
.has_clocks = true,
|
|
};
|
|
|
|
static const struct platform_device_id s3c24xx_dma_driver_ids[] = {
|
|
{
|
|
.name = "s3c2410-dma",
|
|
.driver_data = (kernel_ulong_t)&soc_s3c2410,
|
|
}, {
|
|
.name = "s3c2412-dma",
|
|
.driver_data = (kernel_ulong_t)&soc_s3c2412,
|
|
}, {
|
|
.name = "s3c2443-dma",
|
|
.driver_data = (kernel_ulong_t)&soc_s3c2443,
|
|
},
|
|
{ },
|
|
};
|
|
|
|
static struct soc_data *s3c24xx_dma_get_soc_data(struct platform_device *pdev)
|
|
{
|
|
return (struct soc_data *)
|
|
platform_get_device_id(pdev)->driver_data;
|
|
}
|
|
|
|
static int s3c24xx_dma_probe(struct platform_device *pdev)
|
|
{
|
|
const struct s3c24xx_dma_platdata *pdata = dev_get_platdata(&pdev->dev);
|
|
struct s3c24xx_dma_engine *s3cdma;
|
|
struct soc_data *sdata;
|
|
struct resource *res;
|
|
int ret;
|
|
int i;
|
|
|
|
if (!pdata) {
|
|
dev_err(&pdev->dev, "platform data missing\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* Basic sanity check */
|
|
if (pdata->num_phy_channels > MAX_DMA_CHANNELS) {
|
|
dev_err(&pdev->dev, "to many dma channels %d, max %d\n",
|
|
pdata->num_phy_channels, MAX_DMA_CHANNELS);
|
|
return -EINVAL;
|
|
}
|
|
|
|
sdata = s3c24xx_dma_get_soc_data(pdev);
|
|
if (!sdata)
|
|
return -EINVAL;
|
|
|
|
s3cdma = devm_kzalloc(&pdev->dev, sizeof(*s3cdma), GFP_KERNEL);
|
|
if (!s3cdma)
|
|
return -ENOMEM;
|
|
|
|
s3cdma->pdev = pdev;
|
|
s3cdma->pdata = pdata;
|
|
s3cdma->sdata = sdata;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
s3cdma->base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(s3cdma->base))
|
|
return PTR_ERR(s3cdma->base);
|
|
|
|
s3cdma->phy_chans = devm_kcalloc(&pdev->dev,
|
|
pdata->num_phy_channels,
|
|
sizeof(struct s3c24xx_dma_phy),
|
|
GFP_KERNEL);
|
|
if (!s3cdma->phy_chans)
|
|
return -ENOMEM;
|
|
|
|
/* acquire irqs and clocks for all physical channels */
|
|
for (i = 0; i < pdata->num_phy_channels; i++) {
|
|
struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
|
|
char clk_name[6];
|
|
|
|
phy->id = i;
|
|
phy->base = s3cdma->base + (i * sdata->stride);
|
|
phy->host = s3cdma;
|
|
|
|
phy->irq = platform_get_irq(pdev, i);
|
|
if (phy->irq < 0) {
|
|
dev_err(&pdev->dev, "failed to get irq %d, err %d\n",
|
|
i, phy->irq);
|
|
continue;
|
|
}
|
|
|
|
ret = devm_request_irq(&pdev->dev, phy->irq, s3c24xx_dma_irq,
|
|
0, pdev->name, phy);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "Unable to request irq for channel %d, error %d\n",
|
|
i, ret);
|
|
continue;
|
|
}
|
|
|
|
if (sdata->has_clocks) {
|
|
sprintf(clk_name, "dma.%d", i);
|
|
phy->clk = devm_clk_get(&pdev->dev, clk_name);
|
|
if (IS_ERR(phy->clk) && sdata->has_clocks) {
|
|
dev_err(&pdev->dev, "unable to acquire clock for channel %d, error %lu\n",
|
|
i, PTR_ERR(phy->clk));
|
|
continue;
|
|
}
|
|
|
|
ret = clk_prepare(phy->clk);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "clock for phy %d failed, error %d\n",
|
|
i, ret);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
spin_lock_init(&phy->lock);
|
|
phy->valid = true;
|
|
|
|
dev_dbg(&pdev->dev, "physical channel %d is %s\n",
|
|
i, s3c24xx_dma_phy_busy(phy) ? "BUSY" : "FREE");
|
|
}
|
|
|
|
/* Initialize memcpy engine */
|
|
dma_cap_set(DMA_MEMCPY, s3cdma->memcpy.cap_mask);
|
|
dma_cap_set(DMA_PRIVATE, s3cdma->memcpy.cap_mask);
|
|
s3cdma->memcpy.dev = &pdev->dev;
|
|
s3cdma->memcpy.device_free_chan_resources =
|
|
s3c24xx_dma_free_chan_resources;
|
|
s3cdma->memcpy.device_prep_dma_memcpy = s3c24xx_dma_prep_memcpy;
|
|
s3cdma->memcpy.device_tx_status = s3c24xx_dma_tx_status;
|
|
s3cdma->memcpy.device_issue_pending = s3c24xx_dma_issue_pending;
|
|
s3cdma->memcpy.device_config = s3c24xx_dma_set_runtime_config;
|
|
s3cdma->memcpy.device_terminate_all = s3c24xx_dma_terminate_all;
|
|
s3cdma->memcpy.device_synchronize = s3c24xx_dma_synchronize;
|
|
|
|
/* Initialize slave engine for SoC internal dedicated peripherals */
|
|
dma_cap_set(DMA_SLAVE, s3cdma->slave.cap_mask);
|
|
dma_cap_set(DMA_CYCLIC, s3cdma->slave.cap_mask);
|
|
dma_cap_set(DMA_PRIVATE, s3cdma->slave.cap_mask);
|
|
s3cdma->slave.dev = &pdev->dev;
|
|
s3cdma->slave.device_free_chan_resources =
|
|
s3c24xx_dma_free_chan_resources;
|
|
s3cdma->slave.device_tx_status = s3c24xx_dma_tx_status;
|
|
s3cdma->slave.device_issue_pending = s3c24xx_dma_issue_pending;
|
|
s3cdma->slave.device_prep_slave_sg = s3c24xx_dma_prep_slave_sg;
|
|
s3cdma->slave.device_prep_dma_cyclic = s3c24xx_dma_prep_dma_cyclic;
|
|
s3cdma->slave.device_config = s3c24xx_dma_set_runtime_config;
|
|
s3cdma->slave.device_terminate_all = s3c24xx_dma_terminate_all;
|
|
s3cdma->slave.device_synchronize = s3c24xx_dma_synchronize;
|
|
s3cdma->slave.filter.map = pdata->slave_map;
|
|
s3cdma->slave.filter.mapcnt = pdata->slavecnt;
|
|
s3cdma->slave.filter.fn = s3c24xx_dma_filter;
|
|
|
|
/* Register as many memcpy channels as there are physical channels */
|
|
ret = s3c24xx_dma_init_virtual_channels(s3cdma, &s3cdma->memcpy,
|
|
pdata->num_phy_channels, false);
|
|
if (ret <= 0) {
|
|
dev_warn(&pdev->dev,
|
|
"%s failed to enumerate memcpy channels - %d\n",
|
|
__func__, ret);
|
|
goto err_memcpy;
|
|
}
|
|
|
|
/* Register slave channels */
|
|
ret = s3c24xx_dma_init_virtual_channels(s3cdma, &s3cdma->slave,
|
|
pdata->num_channels, true);
|
|
if (ret <= 0) {
|
|
dev_warn(&pdev->dev,
|
|
"%s failed to enumerate slave channels - %d\n",
|
|
__func__, ret);
|
|
goto err_slave;
|
|
}
|
|
|
|
ret = dma_async_device_register(&s3cdma->memcpy);
|
|
if (ret) {
|
|
dev_warn(&pdev->dev,
|
|
"%s failed to register memcpy as an async device - %d\n",
|
|
__func__, ret);
|
|
goto err_memcpy_reg;
|
|
}
|
|
|
|
ret = dma_async_device_register(&s3cdma->slave);
|
|
if (ret) {
|
|
dev_warn(&pdev->dev,
|
|
"%s failed to register slave as an async device - %d\n",
|
|
__func__, ret);
|
|
goto err_slave_reg;
|
|
}
|
|
|
|
platform_set_drvdata(pdev, s3cdma);
|
|
dev_info(&pdev->dev, "Loaded dma driver with %d physical channels\n",
|
|
pdata->num_phy_channels);
|
|
|
|
return 0;
|
|
|
|
err_slave_reg:
|
|
dma_async_device_unregister(&s3cdma->memcpy);
|
|
err_memcpy_reg:
|
|
s3c24xx_dma_free_virtual_channels(&s3cdma->slave);
|
|
err_slave:
|
|
s3c24xx_dma_free_virtual_channels(&s3cdma->memcpy);
|
|
err_memcpy:
|
|
if (sdata->has_clocks)
|
|
for (i = 0; i < pdata->num_phy_channels; i++) {
|
|
struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
|
|
if (phy->valid)
|
|
clk_unprepare(phy->clk);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void s3c24xx_dma_free_irq(struct platform_device *pdev,
|
|
struct s3c24xx_dma_engine *s3cdma)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < s3cdma->pdata->num_phy_channels; i++) {
|
|
struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
|
|
|
|
devm_free_irq(&pdev->dev, phy->irq, phy);
|
|
}
|
|
}
|
|
|
|
static int s3c24xx_dma_remove(struct platform_device *pdev)
|
|
{
|
|
const struct s3c24xx_dma_platdata *pdata = dev_get_platdata(&pdev->dev);
|
|
struct s3c24xx_dma_engine *s3cdma = platform_get_drvdata(pdev);
|
|
struct soc_data *sdata = s3c24xx_dma_get_soc_data(pdev);
|
|
int i;
|
|
|
|
dma_async_device_unregister(&s3cdma->slave);
|
|
dma_async_device_unregister(&s3cdma->memcpy);
|
|
|
|
s3c24xx_dma_free_irq(pdev, s3cdma);
|
|
|
|
s3c24xx_dma_free_virtual_channels(&s3cdma->slave);
|
|
s3c24xx_dma_free_virtual_channels(&s3cdma->memcpy);
|
|
|
|
if (sdata->has_clocks)
|
|
for (i = 0; i < pdata->num_phy_channels; i++) {
|
|
struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
|
|
if (phy->valid)
|
|
clk_unprepare(phy->clk);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver s3c24xx_dma_driver = {
|
|
.driver = {
|
|
.name = "s3c24xx-dma",
|
|
},
|
|
.id_table = s3c24xx_dma_driver_ids,
|
|
.probe = s3c24xx_dma_probe,
|
|
.remove = s3c24xx_dma_remove,
|
|
};
|
|
|
|
module_platform_driver(s3c24xx_dma_driver);
|
|
|
|
bool s3c24xx_dma_filter(struct dma_chan *chan, void *param)
|
|
{
|
|
struct s3c24xx_dma_chan *s3cchan;
|
|
|
|
if (chan->device->dev->driver != &s3c24xx_dma_driver.driver)
|
|
return false;
|
|
|
|
s3cchan = to_s3c24xx_dma_chan(chan);
|
|
|
|
return s3cchan->id == (uintptr_t)param;
|
|
}
|
|
EXPORT_SYMBOL(s3c24xx_dma_filter);
|
|
|
|
MODULE_DESCRIPTION("S3C24XX DMA Driver");
|
|
MODULE_AUTHOR("Heiko Stuebner");
|
|
MODULE_LICENSE("GPL v2");
|