Release 4.12 drivers/dma/nbpfaxi.c
  
  
  
/*
 * Copyright (C) 2013-2014 Renesas Electronics Europe Ltd.
 * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 */
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <dt-bindings/dma/nbpfaxi.h>
#include "dmaengine.h"
#define NBPF_REG_CHAN_OFFSET	0
#define NBPF_REG_CHAN_SIZE	0x40
/* Channel Current Transaction Byte register */
#define NBPF_CHAN_CUR_TR_BYTE	0x20
/* Channel Status register */
#define NBPF_CHAN_STAT	0x24
#define NBPF_CHAN_STAT_EN	1
#define NBPF_CHAN_STAT_TACT	4
#define NBPF_CHAN_STAT_ERR	0x10
#define NBPF_CHAN_STAT_END	0x20
#define NBPF_CHAN_STAT_TC	0x40
#define NBPF_CHAN_STAT_DER	0x400
/* Channel Control register */
#define NBPF_CHAN_CTRL	0x28
#define NBPF_CHAN_CTRL_SETEN	1
#define NBPF_CHAN_CTRL_CLREN	2
#define NBPF_CHAN_CTRL_STG	4
#define NBPF_CHAN_CTRL_SWRST	8
#define NBPF_CHAN_CTRL_CLRRQ	0x10
#define NBPF_CHAN_CTRL_CLREND	0x20
#define NBPF_CHAN_CTRL_CLRTC	0x40
#define NBPF_CHAN_CTRL_SETSUS	0x100
#define NBPF_CHAN_CTRL_CLRSUS	0x200
/* Channel Configuration register */
#define NBPF_CHAN_CFG	0x2c
#define NBPF_CHAN_CFG_SEL	7		
/* terminal SELect: 0..7 */
#define NBPF_CHAN_CFG_REQD	8		
/* REQuest Direction: DMAREQ is 0: input, 1: output */
#define NBPF_CHAN_CFG_LOEN	0x10		
/* LOw ENable: low DMA request line is: 0: inactive, 1: active */
#define NBPF_CHAN_CFG_HIEN	0x20		
/* HIgh ENable: high DMA request line is: 0: inactive, 1: active */
#define NBPF_CHAN_CFG_LVL	0x40		
/* LeVeL: DMA request line is sensed as 0: edge, 1: level */
#define NBPF_CHAN_CFG_AM	0x700		
/* ACK Mode: 0: Pulse mode, 1: Level mode, b'1x: Bus Cycle */
#define NBPF_CHAN_CFG_SDS	0xf000		
/* Source Data Size: 0: 8 bits,... , 7: 1024 bits */
#define NBPF_CHAN_CFG_DDS	0xf0000		
/* Destination Data Size: as above */
#define NBPF_CHAN_CFG_SAD	0x100000	
/* Source ADdress counting: 0: increment, 1: fixed */
#define NBPF_CHAN_CFG_DAD	0x200000	
/* Destination ADdress counting: 0: increment, 1: fixed */
#define NBPF_CHAN_CFG_TM	0x400000	
/* Transfer Mode: 0: single, 1: block TM */
#define NBPF_CHAN_CFG_DEM	0x1000000	
/* DMAEND interrupt Mask */
#define NBPF_CHAN_CFG_TCM	0x2000000	
/* DMATCO interrupt Mask */
#define NBPF_CHAN_CFG_SBE	0x8000000	
/* Sweep Buffer Enable */
#define NBPF_CHAN_CFG_RSEL	0x10000000	
/* RM: Register Set sELect */
#define NBPF_CHAN_CFG_RSW	0x20000000	
/* RM: Register Select sWitch */
#define NBPF_CHAN_CFG_REN	0x40000000	
/* RM: Register Set Enable */
#define NBPF_CHAN_CFG_DMS	0x80000000	
/* 0: register mode (RM), 1: link mode (LM) */
#define NBPF_CHAN_NXLA	0x38
#define NBPF_CHAN_CRLA	0x3c
/* Link Header field */
#define NBPF_HEADER_LV	1
#define NBPF_HEADER_LE	2
#define NBPF_HEADER_WBD	4
#define NBPF_HEADER_DIM	8
#define NBPF_CTRL	0x300
#define NBPF_CTRL_PR	1		
/* 0: fixed priority, 1: round robin */
#define NBPF_CTRL_LVINT	2		
/* DMAEND and DMAERR signalling: 0: pulse, 1: level */
#define NBPF_DSTAT_ER	0x314
#define NBPF_DSTAT_END	0x318
#define NBPF_DMA_BUSWIDTHS \
	(BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
         BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
         BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
         BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
         BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
struct nbpf_config {
	
int num_channels;
	
int buffer_size;
};
/*
 * We've got 3 types of objects, used to describe DMA transfers:
 * 1. high-level descriptor, containing a struct dma_async_tx_descriptor object
 *      in it, used to communicate with the user
 * 2. hardware DMA link descriptors, that we pass to DMAC for DMA transfer
 *      queuing, these must be DMAable, using either the streaming DMA API or
 *      allocated from coherent memory - one per SG segment
 * 3. one per SG segment descriptors, used to manage HW link descriptors from
 *      (2). They do not have to be DMAable. They can either be (a) allocated
 *      together with link descriptors as mixed (DMA / CPU) objects, or (b)
 *      separately. Even if allocated separately it would be best to link them
 *      to link descriptors once during channel resource allocation and always
 *      use them as a single object.
 * Therefore for both cases (a) and (b) at run-time objects (2) and (3) shall be
 * treated as a single SG segment descriptor.
 */
struct nbpf_link_reg {
	
u32	header;
	
u32	src_addr;
	
u32	dst_addr;
	
u32	transaction_size;
	
u32	config;
	
u32	interval;
	
u32	extension;
	
u32	next;
} __packed;
struct nbpf_device;
struct nbpf_channel;
struct nbpf_desc;
struct nbpf_link_desc {
	
struct nbpf_link_reg *hwdesc;
	
dma_addr_t hwdesc_dma_addr;
	
struct nbpf_desc *desc;
	
struct list_head node;
};
/**
 * struct nbpf_desc - DMA transfer descriptor
 * @async_tx:   dmaengine object
 * @user_wait:  waiting for a user ack
 * @length:     total transfer length
 * @sg:         list of hardware descriptors, represented by struct nbpf_link_desc
 * @node:       member in channel descriptor lists
 */
struct nbpf_desc {
	
struct dma_async_tx_descriptor async_tx;
	
bool user_wait;
	
size_t length;
	
struct nbpf_channel *chan;
	
struct list_head sg;
	
struct list_head node;
};
/* Take a wild guess: allocate 4 segments per descriptor */
#define NBPF_SEGMENTS_PER_DESC 4
#define NBPF_DESCS_PER_PAGE ((PAGE_SIZE - sizeof(struct list_head)) /       \
        (sizeof(struct nbpf_desc) +                                     \
         NBPF_SEGMENTS_PER_DESC *                                       \
         (sizeof(struct nbpf_link_desc) + sizeof(struct nbpf_link_reg))))
#define NBPF_SEGMENTS_PER_PAGE (NBPF_SEGMENTS_PER_DESC * NBPF_DESCS_PER_PAGE)
struct nbpf_desc_page {
	
struct list_head node;
	
struct nbpf_desc desc[NBPF_DESCS_PER_PAGE];
	
struct nbpf_link_desc ldesc[NBPF_SEGMENTS_PER_PAGE];
	
struct nbpf_link_reg hwdesc[NBPF_SEGMENTS_PER_PAGE];
};
/**
 * struct nbpf_channel - one DMAC channel
 * @dma_chan:   standard dmaengine channel object
 * @base:       register address base
 * @nbpf:       DMAC
 * @name:       IRQ name
 * @irq:        IRQ number
 * @slave_addr: address for slave DMA
 * @slave_width:slave data size in bytes
 * @slave_burst:maximum slave burst size in bytes
 * @terminal:   DMA terminal, assigned to this channel
 * @dmarq_cfg:  DMA request line configuration - high / low, edge / level for NBPF_CHAN_CFG
 * @flags:      configuration flags from DT
 * @lock:       protect descriptor lists
 * @free_links: list of free link descriptors
 * @free:       list of free descriptors
 * @queued:     list of queued descriptors
 * @active:     list of descriptors, scheduled for processing
 * @done:       list of completed descriptors, waiting post-processing
 * @desc_page:  list of additionally allocated descriptor pages - if any
 */
struct nbpf_channel {
	
struct dma_chan dma_chan;
	
struct tasklet_struct tasklet;
	
void __iomem *base;
	
struct nbpf_device *nbpf;
	
char name[16];
	
int irq;
	
dma_addr_t slave_src_addr;
	
size_t slave_src_width;
	
size_t slave_src_burst;
	
dma_addr_t slave_dst_addr;
	
size_t slave_dst_width;
	
size_t slave_dst_burst;
	
unsigned int terminal;
	
u32 dmarq_cfg;
	
unsigned long flags;
	
spinlock_t lock;
	
struct list_head free_links;
	
struct list_head free;
	
struct list_head queued;
	
struct list_head active;
	
struct list_head done;
	
struct list_head desc_page;
	
struct nbpf_desc *running;
	
bool paused;
};
struct nbpf_device {
	
struct dma_device dma_dev;
	
void __iomem *base;
	
u32 max_burst_mem_read;
	
u32 max_burst_mem_write;
	
struct clk *clk;
	
const struct nbpf_config *config;
	
unsigned int eirq;
	
struct nbpf_channel chan[];
};
enum nbpf_model {
	
NBPF1B4,
	
NBPF1B8,
	
NBPF1B16,
	
NBPF4B4,
	
NBPF4B8,
	
NBPF4B16,
	
NBPF8B4,
	
NBPF8B8,
	
NBPF8B16,
};
static struct nbpf_config nbpf_cfg[] = {
	[NBPF1B4] = {
		.num_channels = 1,
		.buffer_size = 4,
        },
	[NBPF1B8] = {
		.num_channels = 1,
		.buffer_size = 8,
        },
	[NBPF1B16] = {
		.num_channels = 1,
		.buffer_size = 16,
        },
	[NBPF4B4] = {
		.num_channels = 4,
		.buffer_size = 4,
        },
	[NBPF4B8] = {
		.num_channels = 4,
		.buffer_size = 8,
        },
	[NBPF4B16] = {
		.num_channels = 4,
		.buffer_size = 16,
        },
	[NBPF8B4] = {
		.num_channels = 8,
		.buffer_size = 4,
        },
	[NBPF8B8] = {
		.num_channels = 8,
		.buffer_size = 8,
        },
	[NBPF8B16] = {
		.num_channels = 8,
		.buffer_size = 16,
        },
};
#define nbpf_to_chan(d) container_of(d, struct nbpf_channel, dma_chan)
/*
 * dmaengine drivers seem to have a lot in common and instead of sharing more
 * code, they reimplement those common algorithms independently. In this driver
 * we try to separate the hardware-specific part from the (largely) generic
 * part. This improves code readability and makes it possible in the future to
 * reuse the generic code in form of a helper library. That generic code should
 * be suitable for various DMA controllers, using transfer descriptors in RAM
 * and pushing one SG list at a time to the DMA controller.
 */
/*              Hardware-specific part          */
static inline u32 nbpf_chan_read(struct nbpf_channel *chan,
				 unsigned int offset)
{
	u32 data = ioread32(chan->base + offset);
	dev_dbg(chan->dma_chan.device->dev, "%s(0x%p + 0x%x) = 0x%x\n",
		__func__, chan->base, offset, data);
	return data;
}
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static inline void nbpf_chan_write(struct nbpf_channel *chan,
				   unsigned int offset, u32 data)
{
	iowrite32(data, chan->base + offset);
	dev_dbg(chan->dma_chan.device->dev, "%s(0x%p + 0x%x) = 0x%x\n",
		__func__, chan->base, offset, data);
}
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static inline u32 nbpf_read(struct nbpf_device *nbpf,
			    unsigned int offset)
{
	u32 data = ioread32(nbpf->base + offset);
	dev_dbg(nbpf->dma_dev.dev, "%s(0x%p + 0x%x) = 0x%x\n",
		__func__, nbpf->base, offset, data);
	return data;
}
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static inline void nbpf_write(struct nbpf_device *nbpf,
			      unsigned int offset, u32 data)
{
	iowrite32(data, nbpf->base + offset);
	dev_dbg(nbpf->dma_dev.dev, "%s(0x%p + 0x%x) = 0x%x\n",
		__func__, nbpf->base, offset, data);
}
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static void nbpf_chan_halt(struct nbpf_channel *chan)
{
	nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_CLREN);
}
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static bool nbpf_status_get(struct nbpf_channel *chan)
{
	u32 status = nbpf_read(chan->nbpf, NBPF_DSTAT_END);
	return status & BIT(chan - chan->nbpf->chan);
}
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static void nbpf_status_ack(struct nbpf_channel *chan)
{
	nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_CLREND);
}
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static u32 nbpf_error_get(struct nbpf_device *nbpf)
{
	return nbpf_read(nbpf, NBPF_DSTAT_ER);
}
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static struct nbpf_channel *nbpf_error_get_channel(struct nbpf_device *nbpf, u32 error)
{
	return nbpf->chan + __ffs(error);
}
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static void nbpf_error_clear(struct nbpf_channel *chan)
{
	u32 status;
	int i;
	/* Stop the channel, make sure DMA has been aborted */
	nbpf_chan_halt(chan);
	for (i = 1000; i; i--) {
		status = nbpf_chan_read(chan, NBPF_CHAN_STAT);
		if (!(status & NBPF_CHAN_STAT_TACT))
			break;
		cpu_relax();
	}
	if (!i)
		dev_err(chan->dma_chan.device->dev,
			"%s(): abort timeout, channel status 0x%x\n", __func__, status);
	nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_SWRST);
}
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static int nbpf_start(struct nbpf_desc *desc)
{
	struct nbpf_channel *chan = desc->chan;
	struct nbpf_link_desc *ldesc = list_first_entry(&desc->sg, struct nbpf_link_desc, node);
	nbpf_chan_write(chan, NBPF_CHAN_NXLA, (u32)ldesc->hwdesc_dma_addr);
	nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_SETEN | NBPF_CHAN_CTRL_CLRSUS);
	chan->paused = false;
	/* Software trigger MEMCPY - only MEMCPY uses the block mode */
	if (ldesc->hwdesc->config & NBPF_CHAN_CFG_TM)
		nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_STG);
	dev_dbg(chan->nbpf->dma_dev.dev, "%s(): next 0x%x, cur 0x%x\n", __func__,
		nbpf_chan_read(chan, NBPF_CHAN_NXLA), nbpf_chan_read(chan, NBPF_CHAN_CRLA));
	return 0;
}
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static void nbpf_chan_prepare(struct nbpf_channel *chan)
{
	chan->dmarq_cfg = (chan->flags & NBPF_SLAVE_RQ_HIGH ? NBPF_CHAN_CFG_HIEN : 0) |
		(chan->flags & NBPF_SLAVE_RQ_LOW ? NBPF_CHAN_CFG_LOEN : 0) |
		(chan->flags & NBPF_SLAVE_RQ_LEVEL ?
		 NBPF_CHAN_CFG_LVL | (NBPF_CHAN_CFG_AM & 0x200) : 0) |
		chan->terminal;
}
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static void nbpf_chan_prepare_default(struct nbpf_channel *chan)
{
	/* Don't output DMAACK */
	chan->dmarq_cfg = NBPF_CHAN_CFG_AM & 0x400;
	chan->terminal = 0;
	chan->flags = 0;
}
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static void nbpf_chan_configure(struct nbpf_channel *chan)
{
	/*
         * We assume, that only the link mode and DMA request line configuration
         * have to be set in the configuration register manually. Dynamic
         * per-transfer configuration will be loaded from transfer descriptors.
         */
	nbpf_chan_write(chan, NBPF_CHAN_CFG, NBPF_CHAN_CFG_DMS | chan->dmarq_cfg);
}
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static u32 nbpf_xfer_ds(struct nbpf_device *nbpf, size_t size,
			enum dma_transfer_direction direction)
{
	int max_burst = nbpf->config->buffer_size * 8;
	if (nbpf->max_burst_mem_read || nbpf->max_burst_mem_write) {
		switch (direction) {
		case DMA_MEM_TO_MEM:
			max_burst = min_not_zero(nbpf->max_burst_mem_read,
						 nbpf->max_burst_mem_write);
			break;
		case DMA_MEM_TO_DEV:
			if (nbpf->max_burst_mem_read)
				max_burst = nbpf->max_burst_mem_read;
			break;
		case DMA_DEV_TO_MEM:
			if (nbpf->max_burst_mem_write)
				max_burst = nbpf->max_burst_mem_write;
			break;
		case DMA_DEV_TO_DEV:
		default:
			break;
		}
	}
	/* Maximum supported bursts depend on the buffer size */
	return min_t(int, __ffs(size), ilog2(max_burst));
}
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static size_t nbpf_xfer_size(struct nbpf_device *nbpf,
			     enum dma_slave_buswidth width, u32 burst)
{
	size_t size;
	if (!burst)
		burst = 1;
	switch (width) {
	case DMA_SLAVE_BUSWIDTH_8_BYTES:
		size = 8 * burst;
		break;
	case DMA_SLAVE_BUSWIDTH_4_BYTES:
		size = 4 * burst;
		break;
	case DMA_SLAVE_BUSWIDTH_2_BYTES:
		size = 2 * burst;
		break;
	default:
		pr_warn("%s(): invalid bus width %u\n", __func__, width);
	case DMA_SLAVE_BUSWIDTH_1_BYTE:
		size = burst;
	}
	return nbpf_xfer_ds(nbpf, size, DMA_TRANS_NONE);
}
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/*
 * We need a way to recognise slaves, whose data is sent "raw" over the bus,
 * i.e. it isn't known in advance how many bytes will be received. Therefore
 * the slave driver has to provide a "large enough" buffer and either read the
 * buffer, when it is full, or detect, that some data has arrived, then wait for
 * a timeout, if no more data arrives - receive what's already there. We want to
 * handle such slaves in a special way to allow an optimised mode for other
 * users, for whom the amount of data is known in advance. So far there's no way
 * to recognise such slaves. We use a data-width check to distinguish between
 * the SD host and the PL011 UART.
 */
static int nbpf_prep_one(struct nbpf_link_desc *ldesc,
			 enum dma_transfer_direction direction,
			 dma_addr_t src, dma_addr_t dst, size_t size, bool last)
{
	struct nbpf_link_reg *hwdesc = ldesc->hwdesc;
	struct nbpf_desc *desc = ldesc->desc;
	struct nbpf_channel *chan = desc->chan;
	struct device *dev = chan->dma_chan.device->dev;
	size_t mem_xfer, slave_xfer;
	bool can_burst;
	hwdesc->header = NBPF_HEADER_WBD | NBPF_HEADER_LV |
		(last ? NBPF_HEADER_LE : 0);
	hwdesc->src_addr = src;
	hwdesc->dst_addr = dst;
	hwdesc->transaction_size = size;
	/*
         * set config: SAD, DAD, DDS, SDS, etc.
         * Note on transfer sizes: the DMAC can perform unaligned DMA transfers,
         * but it is important to have transaction size a multiple of both
         * receiver and transmitter transfer sizes. It is also possible to use
         * different RAM and device transfer sizes, and it does work well with
         * some devices, e.g. with V08R07S01E SD host controllers, which can use
         * 128 byte transfers. But this doesn't work with other devices,
         * especially when the transaction size is unknown. This is the case,
         * e.g. with serial drivers like amba-pl011.c. For reception it sets up
         * the transaction size of 4K and if fewer bytes are received, it
         * pauses DMA and reads out data received via DMA as well as those left
         * in the Rx FIFO. For this to work with the RAM side using burst
         * transfers we enable the SBE bit and terminate the transfer in our
         * .device_pause handler.
         */
	mem_xfer = nbpf_xfer_ds(chan->nbpf, size, direction);
	switch (direction) {
	case DMA_DEV_TO_MEM:
		can_burst = chan->slave_src_width >= 3;
		slave_xfer = min(mem_xfer, can_burst ?
				 chan->slave_src_burst : chan->slave_src_width);
		/*
                 * Is the slave narrower than 64 bits, i.e. isn't using the full
                 * bus width and cannot use bursts?
                 */
		if (mem_xfer > chan->slave_src_burst && !can_burst)
			mem_xfer = chan->slave_src_burst;
		/* Device-to-RAM DMA is unreliable without REQD set */
		hwdesc->config = NBPF_CHAN_CFG_SAD | (NBPF_CHAN_CFG_DDS & (mem_xfer << 16)) |
			(NBPF_CHAN_CFG_SDS & (slave_xfer << 12)) | NBPF_CHAN_CFG_REQD |
			NBPF_CHAN_CFG_SBE;
		break;
	case DMA_MEM_TO_DEV:
		slave_xfer = min(mem_xfer, chan->slave_dst_width >= 3 ?
				 chan->slave_dst_burst : chan->slave_dst_width);
		hwdesc->config = NBPF_CHAN_CFG_DAD | (NBPF_CHAN_CFG_SDS & (mem_xfer << 12)) |
			(NBPF_CHAN_CFG_DDS & (slave_xfer << 16)) | NBPF_CHAN_CFG_REQD;
		break;
	case DMA_MEM_TO_MEM:
		hwdesc->config = NBPF_CHAN_CFG_TCM | NBPF_CHAN_CFG_TM |
			(NBPF_CHAN_CFG_SDS & (mem_xfer << 12)) |
			(NBPF_CHAN_CFG_DDS & (mem_xfer << 16));
		break;
	default:
		return -EINVAL;
	}
	hwdesc->config |= chan->dmarq_cfg | (last ? 0 : NBPF_CHAN_CFG_DEM) |
		NBPF_CHAN_CFG_DMS;
	dev_dbg(dev, "%s(): desc @ %pad: hdr 0x%x, cfg 0x%x, %zu @ %pad -> %pad\n",
		__func__, &ldesc->hwdesc_dma_addr, hwdesc->header,
		hwdesc->config, size, &src, &dst);
	dma_sync_single_for_device(dev, ldesc->hwdesc_dma_addr, sizeof(*hwdesc),
				   DMA_TO_DEVICE);
	return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 362 | 99.18% | 1 | 33.33% | 
| Niklas Cassel | 2 | 0.55% | 1 | 33.33% | 
| Vinod Koul | 1 | 0.27% | 1 | 33.33% | 
| Total | 365 | 100.00% | 3 | 100.00% | 
static size_t nbpf_bytes_left(struct nbpf_channel *chan)
{
	return nbpf_chan_read(chan, NBPF_CHAN_CUR_TR_BYTE);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 19 | 100.00% | 1 | 100.00% | 
| Total | 19 | 100.00% | 1 | 100.00% | 
static void nbpf_configure(struct nbpf_device *nbpf)
{
	nbpf_write(nbpf, NBPF_CTRL, NBPF_CTRL_LVINT);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 20 | 100.00% | 1 | 100.00% | 
| Total | 20 | 100.00% | 1 | 100.00% | 
/*              Generic part                    */
/* DMA ENGINE functions */
static void nbpf_issue_pending(struct dma_chan *dchan)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	unsigned long flags;
	dev_dbg(dchan->device->dev, "Entry %s()\n", __func__);
	spin_lock_irqsave(&chan->lock, flags);
	if (list_empty(&chan->queued))
		goto unlock;
	list_splice_tail_init(&chan->queued, &chan->active);
	if (!chan->running) {
		struct nbpf_desc *desc = list_first_entry(&chan->active,
						struct nbpf_desc, node);
		if (!nbpf_start(desc))
			chan->running = desc;
	}
unlock:
	spin_unlock_irqrestore(&chan->lock, flags);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 127 | 100.00% | 1 | 100.00% | 
| Total | 127 | 100.00% | 1 | 100.00% | 
static enum dma_status nbpf_tx_status(struct dma_chan *dchan,
		dma_cookie_t cookie, struct dma_tx_state *state)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	enum dma_status status = dma_cookie_status(dchan, cookie, state);
	if (state) {
		dma_cookie_t running;
		unsigned long flags;
		spin_lock_irqsave(&chan->lock, flags);
		running = chan->running ? chan->running->async_tx.cookie : -EINVAL;
		if (cookie == running) {
			state->residue = nbpf_bytes_left(chan);
			dev_dbg(dchan->device->dev, "%s(): residue %u\n", __func__,
				state->residue);
		} else if (status == DMA_IN_PROGRESS) {
			struct nbpf_desc *desc;
			bool found = false;
			list_for_each_entry(desc, &chan->active, node)
				if (desc->async_tx.cookie == cookie) {
					found = true;
					break;
				}
			if (!found)
				list_for_each_entry(desc, &chan->queued, node)
					if (desc->async_tx.cookie == cookie) {
						found = true;
						break;
					}
			state->residue = found ? desc->length : 0;
		}
		spin_unlock_irqrestore(&chan->lock, flags);
	}
	if (chan->paused)
		status = DMA_PAUSED;
	return status;
}
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| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 226 | 100.00% | 1 | 100.00% | 
| Total | 226 | 100.00% | 1 | 100.00% | 
static dma_cookie_t nbpf_tx_submit(struct dma_async_tx_descriptor *tx)
{
	struct nbpf_desc *desc = container_of(tx, struct nbpf_desc, async_tx);
	struct nbpf_channel *chan = desc->chan;
	unsigned long flags;
	dma_cookie_t cookie;
	spin_lock_irqsave(&chan->lock, flags);
	cookie = dma_cookie_assign(tx);
	list_add_tail(&desc->node, &chan->queued);
	spin_unlock_irqrestore(&chan->lock, flags);
	dev_dbg(chan->dma_chan.device->dev, "Entry %s(%d)\n", __func__, cookie);
	return cookie;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 102 | 100.00% | 1 | 100.00% | 
| Total | 102 | 100.00% | 1 | 100.00% | 
static int nbpf_desc_page_alloc(struct nbpf_channel *chan)
{
	struct dma_chan *dchan = &chan->dma_chan;
	struct nbpf_desc_page *dpage = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
	struct nbpf_link_desc *ldesc;
	struct nbpf_link_reg *hwdesc;
	struct nbpf_desc *desc;
	LIST_HEAD(head);
	LIST_HEAD(lhead);
	int i;
	struct device *dev = dchan->device->dev;
	if (!dpage)
		return -ENOMEM;
	dev_dbg(dev, "%s(): alloc %lu descriptors, %lu segments, total alloc %zu\n",
		__func__, NBPF_DESCS_PER_PAGE, NBPF_SEGMENTS_PER_PAGE, sizeof(*dpage));
	for (i = 0, ldesc = dpage->ldesc, hwdesc = dpage->hwdesc;
	     i < ARRAY_SIZE(dpage->ldesc);
	     i++, ldesc++, hwdesc++) {
		ldesc->hwdesc = hwdesc;
		list_add_tail(&ldesc->node, &lhead);
		ldesc->hwdesc_dma_addr = dma_map_single(dchan->device->dev,
					hwdesc, sizeof(*hwdesc), DMA_TO_DEVICE);
		dev_dbg(dev, "%s(): mapped 0x%p to %pad\n", __func__,
			hwdesc, &ldesc->hwdesc_dma_addr);
	}
	for (i = 0, desc = dpage->desc;
	     i < ARRAY_SIZE(dpage->desc);
	     i++, desc++) {
		dma_async_tx_descriptor_init(&desc->async_tx, dchan);
		desc->async_tx.tx_submit = nbpf_tx_submit;
		desc->chan = chan;
		INIT_LIST_HEAD(&desc->sg);
		list_add_tail(&desc->node, &head);
	}
	/*
         * This function cannot be called from interrupt context, so, no need to
         * save flags
         */
	spin_lock_irq(&chan->lock);
	list_splice_tail(&lhead, &chan->free_links);
	list_splice_tail(&head, &chan->free);
	list_add(&dpage->node, &chan->desc_page);
	spin_unlock_irq(&chan->lock);
	return ARRAY_SIZE(dpage->desc);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 330 | 100.00% | 1 | 100.00% | 
| Total | 330 | 100.00% | 1 | 100.00% | 
static void nbpf_desc_put(struct nbpf_desc *desc)
{
	struct nbpf_channel *chan = desc->chan;
	struct nbpf_link_desc *ldesc, *tmp;
	unsigned long flags;
	spin_lock_irqsave(&chan->lock, flags);
	list_for_each_entry_safe(ldesc, tmp, &desc->sg, node)
		list_move(&ldesc->node, &chan->free_links);
	list_add(&desc->node, &chan->free);
	spin_unlock_irqrestore(&chan->lock, flags);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 88 | 100.00% | 1 | 100.00% | 
| Total | 88 | 100.00% | 1 | 100.00% | 
static void nbpf_scan_acked(struct nbpf_channel *chan)
{
	struct nbpf_desc *desc, *tmp;
	unsigned long flags;
	LIST_HEAD(head);
	spin_lock_irqsave(&chan->lock, flags);
	list_for_each_entry_safe(desc, tmp, &chan->done, node)
		if (async_tx_test_ack(&desc->async_tx) && desc->user_wait) {
			list_move(&desc->node, &head);
			desc->user_wait = false;
		}
	spin_unlock_irqrestore(&chan->lock, flags);
	list_for_each_entry_safe(desc, tmp, &head, node) {
		list_del(&desc->node);
		nbpf_desc_put(desc);
	}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 116 | 100.00% | 1 | 100.00% | 
| Total | 116 | 100.00% | 1 | 100.00% | 
/*
 * We have to allocate descriptors with the channel lock dropped. This means,
 * before we re-acquire the lock buffers can be taken already, so we have to
 * re-check after re-acquiring the lock and possibly retry, if buffers are gone
 * again.
 */
static struct nbpf_desc *nbpf_desc_get(struct nbpf_channel *chan, size_t len)
{
	struct nbpf_desc *desc = NULL;
	struct nbpf_link_desc *ldesc, *prev = NULL;
	nbpf_scan_acked(chan);
	spin_lock_irq(&chan->lock);
	do {
		int i = 0, ret;
		if (list_empty(&chan->free)) {
			/* No more free descriptors */
			spin_unlock_irq(&chan->lock);
			ret = nbpf_desc_page_alloc(chan);
			if (ret < 0)
				return NULL;
			spin_lock_irq(&chan->lock);
			continue;
		}
		desc = list_first_entry(&chan->free, struct nbpf_desc, node);
		list_del(&desc->node);
		do {
			if (list_empty(&chan->free_links)) {
				/* No more free link descriptors */
				spin_unlock_irq(&chan->lock);
				ret = nbpf_desc_page_alloc(chan);
				if (ret < 0) {
					nbpf_desc_put(desc);
					return NULL;
				}
				spin_lock_irq(&chan->lock);
				continue;
			}
			ldesc = list_first_entry(&chan->free_links,
						 struct nbpf_link_desc, node);
			ldesc->desc = desc;
			if (prev)
				prev->hwdesc->next = (u32)ldesc->hwdesc_dma_addr;
			prev = ldesc;
			list_move_tail(&ldesc->node, &desc->sg);
			i++;
		} while (i < len);
	} while (!desc);
	prev->hwdesc->next = 0;
	spin_unlock_irq(&chan->lock);
	return desc;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 271 | 100.00% | 1 | 100.00% | 
| Total | 271 | 100.00% | 1 | 100.00% | 
static void nbpf_chan_idle(struct nbpf_channel *chan)
{
	struct nbpf_desc *desc, *tmp;
	unsigned long flags;
	LIST_HEAD(head);
	spin_lock_irqsave(&chan->lock, flags);
	list_splice_init(&chan->done, &head);
	list_splice_init(&chan->active, &head);
	list_splice_init(&chan->queued, &head);
	chan->running = NULL;
	spin_unlock_irqrestore(&chan->lock, flags);
	list_for_each_entry_safe(desc, tmp, &head, node) {
		dev_dbg(chan->nbpf->dma_dev.dev, "%s(): force-free desc %p cookie %d\n",
			__func__, desc, desc->async_tx.cookie);
		list_del(&desc->node);
		nbpf_desc_put(desc);
	}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 135 | 100.00% | 1 | 100.00% | 
| Total | 135 | 100.00% | 1 | 100.00% | 
static int nbpf_pause(struct dma_chan *dchan)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	dev_dbg(dchan->device->dev, "Entry %s\n", __func__);
	chan->paused = true;
	nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_SETSUS);
	/* See comment in nbpf_prep_one() */
	nbpf_chan_write(chan, NBPF_CHAN_CTRL, NBPF_CHAN_CTRL_CLREN);
	return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Maxime Ripard | 43 | 69.35% | 1 | 50.00% | 
| Guennadi Liakhovetski | 19 | 30.65% | 1 | 50.00% | 
| Total | 62 | 100.00% | 2 | 100.00% | 
static int nbpf_terminate_all(struct dma_chan *dchan)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	dev_dbg(dchan->device->dev, "Entry %s\n", __func__);
	dev_dbg(dchan->device->dev, "Terminating\n");
	nbpf_chan_halt(chan);
	nbpf_chan_idle(chan);
	return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 38 | 65.52% | 1 | 50.00% | 
| Maxime Ripard | 20 | 34.48% | 1 | 50.00% | 
| Total | 58 | 100.00% | 2 | 100.00% | 
static int nbpf_config(struct dma_chan *dchan,
		       struct dma_slave_config *config)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	dev_dbg(dchan->device->dev, "Entry %s\n", __func__);
	/*
         * We could check config->slave_id to match chan->terminal here,
         * but with DT they would be coming from the same source, so
         * such a check would be superflous
         */
	chan->slave_dst_addr = config->dst_addr;
	chan->slave_dst_width = nbpf_xfer_size(chan->nbpf,
					       config->dst_addr_width, 1);
	chan->slave_dst_burst = nbpf_xfer_size(chan->nbpf,
					       config->dst_addr_width,
					       config->dst_maxburst);
	chan->slave_src_addr = config->src_addr;
	chan->slave_src_width = nbpf_xfer_size(chan->nbpf,
					       config->src_addr_width, 1);
	chan->slave_src_burst = nbpf_xfer_size(chan->nbpf,
					       config->src_addr_width,
					       config->src_maxburst);
	return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 94 | 71.76% | 1 | 50.00% | 
| Maxime Ripard | 37 | 28.24% | 1 | 50.00% | 
| Total | 131 | 100.00% | 2 | 100.00% | 
static struct dma_async_tx_descriptor *nbpf_prep_sg(struct nbpf_channel *chan,
		struct scatterlist *src_sg, struct scatterlist *dst_sg,
		size_t len, enum dma_transfer_direction direction,
		unsigned long flags)
{
	struct nbpf_link_desc *ldesc;
	struct scatterlist *mem_sg;
	struct nbpf_desc *desc;
	bool inc_src, inc_dst;
	size_t data_len = 0;
	int i = 0;
	switch (direction) {
	case DMA_DEV_TO_MEM:
		mem_sg = dst_sg;
		inc_src = false;
		inc_dst = true;
		break;
	case DMA_MEM_TO_DEV:
		mem_sg = src_sg;
		inc_src = true;
		inc_dst = false;
		break;
	default:
	case DMA_MEM_TO_MEM:
		mem_sg = src_sg;
		inc_src = true;
		inc_dst = true;
	}
	desc = nbpf_desc_get(chan, len);
	if (!desc)
		return NULL;
	desc->async_tx.flags = flags;
	desc->async_tx.cookie = -EBUSY;
	desc->user_wait = false;
	/*
         * This is a private descriptor list, and we own the descriptor. No need
         * to lock.
         */
	list_for_each_entry(ldesc, &desc->sg, node) {
		int ret = nbpf_prep_one(ldesc, direction,
					sg_dma_address(src_sg),
					sg_dma_address(dst_sg),
					sg_dma_len(mem_sg),
					i == len - 1);
		if (ret < 0) {
			nbpf_desc_put(desc);
			return NULL;
		}
		data_len += sg_dma_len(mem_sg);
		if (inc_src)
			src_sg = sg_next(src_sg);
		if (inc_dst)
			dst_sg = sg_next(dst_sg);
		mem_sg = direction == DMA_DEV_TO_MEM ? dst_sg : src_sg;
		i++;
	}
	desc->length = data_len;
	/* The user has to return the descriptor to us ASAP via .tx_submit() */
	return &desc->async_tx;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 271 | 100.00% | 1 | 100.00% | 
| Total | 271 | 100.00% | 1 | 100.00% | 
static struct dma_async_tx_descriptor *nbpf_prep_memcpy(
	struct dma_chan *dchan, dma_addr_t dst, dma_addr_t src,
	size_t len, unsigned long flags)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	struct scatterlist dst_sg;
	struct scatterlist src_sg;
	sg_init_table(&dst_sg, 1);
	sg_init_table(&src_sg, 1);
	sg_dma_address(&dst_sg) = dst;
	sg_dma_address(&src_sg) = src;
	sg_dma_len(&dst_sg) = len;
	sg_dma_len(&src_sg) = len;
	dev_dbg(dchan->device->dev, "%s(): %zu @ %pad -> %pad\n",
		__func__, len, &src, &dst);
	return nbpf_prep_sg(chan, &src_sg, &dst_sg, 1,
			    DMA_MEM_TO_MEM, flags);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 131 | 100.00% | 1 | 100.00% | 
| Total | 131 | 100.00% | 1 | 100.00% | 
static struct dma_async_tx_descriptor *nbpf_prep_memcpy_sg(
	struct dma_chan *dchan,
	struct scatterlist *dst_sg, unsigned int dst_nents,
	struct scatterlist *src_sg, unsigned int src_nents,
	unsigned long flags)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	if (dst_nents != src_nents)
		return NULL;
	return nbpf_prep_sg(chan, src_sg, dst_sg, src_nents,
			    DMA_MEM_TO_MEM, flags);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 70 | 100.00% | 1 | 100.00% | 
| Total | 70 | 100.00% | 1 | 100.00% | 
static struct dma_async_tx_descriptor *nbpf_prep_slave_sg(
	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
	enum dma_transfer_direction direction, unsigned long flags, void *context)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	struct scatterlist slave_sg;
	dev_dbg(dchan->device->dev, "Entry %s()\n", __func__);
	sg_init_table(&slave_sg, 1);
	switch (direction) {
	case DMA_MEM_TO_DEV:
		sg_dma_address(&slave_sg) = chan->slave_dst_addr;
		return nbpf_prep_sg(chan, sgl, &slave_sg, sg_len,
				    direction, flags);
	case DMA_DEV_TO_MEM:
		sg_dma_address(&slave_sg) = chan->slave_src_addr;
		return nbpf_prep_sg(chan, &slave_sg, sgl, sg_len,
				    direction, flags);
	default:
		return NULL;
	}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 139 | 100.00% | 1 | 100.00% | 
| Total | 139 | 100.00% | 1 | 100.00% | 
static int nbpf_alloc_chan_resources(struct dma_chan *dchan)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	int ret;
	INIT_LIST_HEAD(&chan->free);
	INIT_LIST_HEAD(&chan->free_links);
	INIT_LIST_HEAD(&chan->queued);
	INIT_LIST_HEAD(&chan->active);
	INIT_LIST_HEAD(&chan->done);
	ret = nbpf_desc_page_alloc(chan);
	if (ret < 0)
		return ret;
	dev_dbg(dchan->device->dev, "Entry %s(): terminal %u\n", __func__,
		chan->terminal);
	nbpf_chan_configure(chan);
	return ret;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 105 | 100.00% | 1 | 100.00% | 
| Total | 105 | 100.00% | 1 | 100.00% | 
static void nbpf_free_chan_resources(struct dma_chan *dchan)
{
	struct nbpf_channel *chan = nbpf_to_chan(dchan);
	struct nbpf_desc_page *dpage, *tmp;
	dev_dbg(dchan->device->dev, "Entry %s()\n", __func__);
	nbpf_chan_halt(chan);
	nbpf_chan_idle(chan);
	/* Clean up for if a channel is re-used for MEMCPY after slave DMA */
	nbpf_chan_prepare_default(chan);
	list_for_each_entry_safe(dpage, tmp, &chan->desc_page, node) {
		struct nbpf_link_desc *ldesc;
		int i;
		list_del(&dpage->node);
		for (i = 0, ldesc = dpage->ldesc;
		     i < ARRAY_SIZE(dpage->ldesc);
		     i++, ldesc++)
			dma_unmap_single(dchan->device->dev, ldesc->hwdesc_dma_addr,
					 sizeof(*ldesc->hwdesc), DMA_TO_DEVICE);
		free_page((unsigned long)dpage);
	}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 145 | 100.00% | 2 | 100.00% | 
| Total | 145 | 100.00% | 2 | 100.00% | 
static struct dma_chan *nbpf_of_xlate(struct of_phandle_args *dma_spec,
				      struct of_dma *ofdma)
{
	struct nbpf_device *nbpf = ofdma->of_dma_data;
	struct dma_chan *dchan;
	struct nbpf_channel *chan;
	if (dma_spec->args_count != 2)
		return NULL;
	dchan = dma_get_any_slave_channel(&nbpf->dma_dev);
	if (!dchan)
		return NULL;
	dev_dbg(dchan->device->dev, "Entry %s(%s)\n", __func__,
		dma_spec->np->name);
	chan = nbpf_to_chan(dchan);
	chan->terminal = dma_spec->args[0];
	chan->flags = dma_spec->args[1];
	nbpf_chan_prepare(chan);
	nbpf_chan_configure(chan);
	return dchan;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 127 | 100.00% | 1 | 100.00% | 
| Total | 127 | 100.00% | 1 | 100.00% | 
static void nbpf_chan_tasklet(unsigned long data)
{
	struct nbpf_channel *chan = (struct nbpf_channel *)data;
	struct nbpf_desc *desc, *tmp;
	struct dmaengine_desc_callback cb;
	while (!list_empty(&chan->done)) {
		bool found = false, must_put, recycling = false;
		spin_lock_irq(&chan->lock);
		list_for_each_entry_safe(desc, tmp, &chan->done, node) {
			if (!desc->user_wait) {
				/* Newly completed descriptor, have to process */
				found = true;
				break;
			} else if (async_tx_test_ack(&desc->async_tx)) {
				/*
                                 * This descriptor was waiting for a user ACK,
                                 * it can be recycled now.
                                 */
				list_del(&desc->node);
				spin_unlock_irq(&chan->lock);
				nbpf_desc_put(desc);
				recycling = true;
				break;
			}
		}
		if (recycling)
			continue;
		if (!found) {
			/* This can happen if TERMINATE_ALL has been called */
			spin_unlock_irq(&chan->lock);
			break;
		}
		dma_cookie_complete(&desc->async_tx);
		/*
                 * With released lock we cannot dereference desc, maybe it's
                 * still on the "done" list
                 */
		if (async_tx_test_ack(&desc->async_tx)) {
			list_del(&desc->node);
			must_put = true;
		} else {
			desc->user_wait = true;
			must_put = false;
		}
		dmaengine_desc_get_callback(&desc->async_tx, &cb);
		/* ack and callback completed descriptor */
		spin_unlock_irq(&chan->lock);
		dmaengine_desc_callback_invoke(&cb, NULL);
		if (must_put)
			nbpf_desc_put(desc);
	}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 223 | 93.70% | 2 | 66.67% | 
| Dave Jiang | 15 | 6.30% | 1 | 33.33% | 
| Total | 238 | 100.00% | 3 | 100.00% | 
static irqreturn_t nbpf_chan_irq(int irq, void *dev)
{
	struct nbpf_channel *chan = dev;
	bool done = nbpf_status_get(chan);
	struct nbpf_desc *desc;
	irqreturn_t ret;
	bool bh = false;
	if (!done)
		return IRQ_NONE;
	nbpf_status_ack(chan);
	dev_dbg(&chan->dma_chan.dev->device, "%s()\n", __func__);
	spin_lock(&chan->lock);
	desc = chan->running;
	if (WARN_ON(!desc)) {
		ret = IRQ_NONE;
		goto unlock;
	} else {
		ret = IRQ_HANDLED;
		bh = true;
	}
	list_move_tail(&desc->node, &chan->done);
	chan->running = NULL;
	if (!list_empty(&chan->active)) {
		desc = list_first_entry(&chan->active,
					struct nbpf_desc, node);
		if (!nbpf_start(desc))
			chan->running = desc;
	}
unlock:
	spin_unlock(&chan->lock);
	if (bh)
		tasklet_schedule(&chan->tasklet);
	return ret;
}
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| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 198 | 100.00% | 2 | 100.00% | 
| Total | 198 | 100.00% | 2 | 100.00% | 
static irqreturn_t nbpf_err_irq(int irq, void *dev)
{
	struct nbpf_device *nbpf = dev;
	u32 error = nbpf_error_get(nbpf);
	dev_warn(nbpf->dma_dev.dev, "DMA error IRQ %u\n", irq);
	if (!error)
		return IRQ_NONE;
	do {
		struct nbpf_channel *chan = nbpf_error_get_channel(nbpf, error);
		/* On error: abort all queued transfers, no callback */
		nbpf_error_clear(chan);
		nbpf_chan_idle(chan);
		error = nbpf_error_get(nbpf);
	} while (error);
	return IRQ_HANDLED;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 90 | 100.00% | 1 | 100.00% | 
| Total | 90 | 100.00% | 1 | 100.00% | 
static int nbpf_chan_probe(struct nbpf_device *nbpf, int n)
{
	struct dma_device *dma_dev = &nbpf->dma_dev;
	struct nbpf_channel *chan = nbpf->chan + n;
	int ret;
	chan->nbpf = nbpf;
	chan->base = nbpf->base + NBPF_REG_CHAN_OFFSET + NBPF_REG_CHAN_SIZE * n;
	INIT_LIST_HEAD(&chan->desc_page);
	spin_lock_init(&chan->lock);
	chan->dma_chan.device = dma_dev;
	dma_cookie_init(&chan->dma_chan);
	nbpf_chan_prepare_default(chan);
	dev_dbg(dma_dev->dev, "%s(): channel %d: -> %p\n", __func__, n, chan->base);
	snprintf(chan->name, sizeof(chan->name), "nbpf %d", n);
	tasklet_init(&chan->tasklet, nbpf_chan_tasklet, (unsigned long)chan);
	ret = devm_request_irq(dma_dev->dev, chan->irq,
			nbpf_chan_irq, IRQF_SHARED,
			chan->name, chan);
	if (ret < 0)
		return ret;
	/* Add the channel to DMA device channel list */
	list_add_tail(&chan->dma_chan.device_node,
		      &dma_dev->channels);
	return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 197 | 100.00% | 2 | 100.00% | 
| Total | 197 | 100.00% | 2 | 100.00% | 
static const struct of_device_id nbpf_match[] = {
	{.compatible = "renesas,nbpfaxi64dmac1b4",	.data = &nbpf_cfg[NBPF1B4]},
	{.compatible = "renesas,nbpfaxi64dmac1b8",	.data = &nbpf_cfg[NBPF1B8]},
	{.compatible = "renesas,nbpfaxi64dmac1b16",	.data = &nbpf_cfg[NBPF1B16]},
	{.compatible = "renesas,nbpfaxi64dmac4b4",	.data = &nbpf_cfg[NBPF4B4]},
	{.compatible = "renesas,nbpfaxi64dmac4b8",	.data = &nbpf_cfg[NBPF4B8]},
	{.compatible = "renesas,nbpfaxi64dmac4b16",	.data = &nbpf_cfg[NBPF4B16]},
	{.compatible = "renesas,nbpfaxi64dmac8b4",	.data = &nbpf_cfg[NBPF8B4]},
	{.compatible = "renesas,nbpfaxi64dmac8b8",	.data = &nbpf_cfg[NBPF8B8]},
	{.compatible = "renesas,nbpfaxi64dmac8b16",	.data = &nbpf_cfg[NBPF8B16]},
	{}
};
MODULE_DEVICE_TABLE(of, nbpf_match);
static int nbpf_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	const struct of_device_id *of_id = of_match_device(nbpf_match, dev);
	struct device_node *np = dev->of_node;
	struct nbpf_device *nbpf;
	struct dma_device *dma_dev;
	struct resource *iomem, *irq_res;
	const struct nbpf_config *cfg;
	int num_channels;
	int ret, irq, eirq, i;
	int irqbuf[9] /* maximum 8 channels + error IRQ */;
	unsigned int irqs = 0;
	BUILD_BUG_ON(sizeof(struct nbpf_desc_page) > PAGE_SIZE);
	/* DT only */
	if (!np || !of_id || !of_id->data)
		return -ENODEV;
	cfg = of_id->data;
	num_channels = cfg->num_channels;
	nbpf = devm_kzalloc(dev, sizeof(*nbpf) + num_channels *
			    sizeof(nbpf->chan[0]), GFP_KERNEL);
	if (!nbpf)
		return -ENOMEM;
	dma_dev = &nbpf->dma_dev;
	dma_dev->dev = dev;
	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	nbpf->base = devm_ioremap_resource(dev, iomem);
	if (IS_ERR(nbpf->base))
		return PTR_ERR(nbpf->base);
	nbpf->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(nbpf->clk))
		return PTR_ERR(nbpf->clk);
	of_property_read_u32(np, "max-burst-mem-read",
			     &nbpf->max_burst_mem_read);
	of_property_read_u32(np, "max-burst-mem-write",
			     &nbpf->max_burst_mem_write);
	nbpf->config = cfg;
	for (i = 0; irqs < ARRAY_SIZE(irqbuf); i++) {
		irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
		if (!irq_res)
			break;
		for (irq = irq_res->start; irq <= irq_res->end;
		     irq++, irqs++)
			irqbuf[irqs] = irq;
	}
	/*
         * 3 IRQ resource schemes are supported:
         * 1. 1 shared IRQ for error and all channels
         * 2. 2 IRQs: one for error and one shared for all channels
         * 3. 1 IRQ for error and an own IRQ for each channel
         */
	if (irqs != 1 && irqs != 2 && irqs != num_channels + 1)
		return -ENXIO;
	if (irqs == 1) {
		eirq = irqbuf[0];
		for (i = 0; i <= num_channels; i++)
			nbpf->chan[i].irq = irqbuf[0];
	} else {
		eirq = platform_get_irq_byname(pdev, "error");
		if (eirq < 0)
			return eirq;
		if (irqs == num_channels + 1) {
			struct nbpf_channel *chan;
			for (i = 0, chan = nbpf->chan; i <= num_channels;
			     i++, chan++) {
				/* Skip the error IRQ */
				if (irqbuf[i] == eirq)
					i++;
				chan->irq = irqbuf[i];
			}
			if (chan != nbpf->chan + num_channels)
				return -EINVAL;
		} else {
			/* 2 IRQs and more than one channel */
			if (irqbuf[0] == eirq)
				irq = irqbuf[1];
			else
				irq = irqbuf[0];
			for (i = 0; i <= num_channels; i++)
				nbpf->chan[i].irq = irq;
		}
	}
	ret = devm_request_irq(dev, eirq, nbpf_err_irq,
			       IRQF_SHARED, "dma error", nbpf);
	if (ret < 0)
		return ret;
	nbpf->eirq = eirq;
	INIT_LIST_HEAD(&dma_dev->channels);
	/* Create DMA Channel */
	for (i = 0; i < num_channels; i++) {
		ret = nbpf_chan_probe(nbpf, i);
		if (ret < 0)
			return ret;
	}
	dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
	dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
	dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask);
	dma_cap_set(DMA_SG, dma_dev->cap_mask);
	/* Common and MEMCPY operations */
	dma_dev->device_alloc_chan_resources
		= nbpf_alloc_chan_resources;
	dma_dev->device_free_chan_resources = nbpf_free_chan_resources;
	dma_dev->device_prep_dma_sg = nbpf_prep_memcpy_sg;
	dma_dev->device_prep_dma_memcpy = nbpf_prep_memcpy;
	dma_dev->device_tx_status = nbpf_tx_status;
	dma_dev->device_issue_pending = nbpf_issue_pending;
	/*
         * If we drop support for unaligned MEMCPY buffer addresses and / or
         * lengths by setting
         * dma_dev->copy_align = 4;
         * then we can set transfer length to 4 bytes in nbpf_prep_one() for
         * DMA_MEM_TO_MEM
         */
	/* Compulsory for DMA_SLAVE fields */
	dma_dev->device_prep_slave_sg = nbpf_prep_slave_sg;
	dma_dev->device_config = nbpf_config;
	dma_dev->device_pause = nbpf_pause;
	dma_dev->device_terminate_all = nbpf_terminate_all;
	dma_dev->src_addr_widths = NBPF_DMA_BUSWIDTHS;
	dma_dev->dst_addr_widths = NBPF_DMA_BUSWIDTHS;
	dma_dev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
	platform_set_drvdata(pdev, nbpf);
	ret = clk_prepare_enable(nbpf->clk);
	if (ret < 0)
		return ret;
	nbpf_configure(nbpf);
	ret = dma_async_device_register(dma_dev);
	if (ret < 0)
		goto e_clk_off;
	ret = of_dma_controller_register(np, nbpf_of_xlate, nbpf);
	if (ret < 0)
		goto e_dma_dev_unreg;
	return 0;
e_dma_dev_unreg:
	dma_async_device_unregister(dma_dev);
e_clk_off:
	clk_disable_unprepare(nbpf->clk);
	return ret;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 769 | 91.66% | 1 | 20.00% | 
| Maxime Ripard | 40 | 4.77% | 2 | 40.00% | 
| Niklas Cassel | 24 | 2.86% | 1 | 20.00% | 
| Vinod Koul | 6 | 0.72% | 1 | 20.00% | 
| Total | 839 | 100.00% | 5 | 100.00% | 
static int nbpf_remove(struct platform_device *pdev)
{
	struct nbpf_device *nbpf = platform_get_drvdata(pdev);
	int i;
	devm_free_irq(&pdev->dev, nbpf->eirq, nbpf);
	for (i = 0; i < nbpf->config->num_channels; i++) {
		struct nbpf_channel *chan = nbpf->chan + i;
		devm_free_irq(&pdev->dev, chan->irq, chan);
		tasklet_kill(&chan->tasklet);
	}
	of_dma_controller_free(pdev->dev.of_node);
	dma_async_device_unregister(&nbpf->dma_dev);
	clk_disable_unprepare(nbpf->clk);
	return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Vinod Koul | 69 | 58.97% | 2 | 66.67% | 
| Guennadi Liakhovetski | 48 | 41.03% | 1 | 33.33% | 
| Total | 117 | 100.00% | 3 | 100.00% | 
static const struct platform_device_id nbpf_ids[] = {
	{"nbpfaxi64dmac1b4",	(kernel_ulong_t)&nbpf_cfg[NBPF1B4]},
	{"nbpfaxi64dmac1b8",	(kernel_ulong_t)&nbpf_cfg[NBPF1B8]},
	{"nbpfaxi64dmac1b16",	(kernel_ulong_t)&nbpf_cfg[NBPF1B16]},
	{"nbpfaxi64dmac4b4",	(kernel_ulong_t)&nbpf_cfg[NBPF4B4]},
	{"nbpfaxi64dmac4b8",	(kernel_ulong_t)&nbpf_cfg[NBPF4B8]},
	{"nbpfaxi64dmac4b16",	(kernel_ulong_t)&nbpf_cfg[NBPF4B16]},
	{"nbpfaxi64dmac8b4",	(kernel_ulong_t)&nbpf_cfg[NBPF8B4]},
	{"nbpfaxi64dmac8b8",	(kernel_ulong_t)&nbpf_cfg[NBPF8B8]},
	{"nbpfaxi64dmac8b16",	(kernel_ulong_t)&nbpf_cfg[NBPF8B16]},
	{},
};
MODULE_DEVICE_TABLE(platform, nbpf_ids);
#ifdef CONFIG_PM
static int nbpf_runtime_suspend(struct device *dev)
{
	struct nbpf_device *nbpf = platform_get_drvdata(to_platform_device(dev));
	clk_disable_unprepare(nbpf->clk);
	return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 34 | 100.00% | 1 | 100.00% | 
| Total | 34 | 100.00% | 1 | 100.00% | 
static int nbpf_runtime_resume(struct device *dev)
{
	struct nbpf_device *nbpf = platform_get_drvdata(to_platform_device(dev));
	return clk_prepare_enable(nbpf->clk);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 32 | 100.00% | 1 | 100.00% | 
| Total | 32 | 100.00% | 1 | 100.00% | 
#endif
static const struct dev_pm_ops nbpf_pm_ops = {
	SET_RUNTIME_PM_OPS(nbpf_runtime_suspend, nbpf_runtime_resume, NULL)
};
static struct platform_driver nbpf_driver = {
	.driver = {
		.name = "dma-nbpf",
		.of_match_table = nbpf_match,
		.pm = &nbpf_pm_ops,
        },
	.id_table = nbpf_ids,
	.probe = nbpf_probe,
	.remove = nbpf_remove,
};
module_platform_driver(nbpf_driver);
MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
MODULE_DESCRIPTION("dmaengine driver for NBPFAXI64* DMACs");
MODULE_LICENSE("GPL v2");
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp | 
| Guennadi Liakhovetski | 6427 | 94.70% | 3 | 23.08% | 
| Maxime Ripard | 140 | 2.06% | 2 | 15.38% | 
| Niklas Cassel | 122 | 1.80% | 1 | 7.69% | 
| Vinod Koul | 80 | 1.18% | 3 | 23.08% | 
| Dave Jiang | 15 | 0.22% | 1 | 7.69% | 
| Rafael J. Wysocki | 1 | 0.01% | 1 | 7.69% | 
| Krzysztof Kozlowski | 1 | 0.01% | 1 | 7.69% | 
| Fengguang Wu | 1 | 0.01% | 1 | 7.69% | 
| Total | 6787 | 100.00% | 13 | 100.00% | 
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