- 根目录:
- drivers
- dma
- sun6i-dma.c
/*
* Copyright (C) 2013-2014 Allwinner Tech Co., Ltd
* Author: Sugar <shuge@allwinnertech.com>
*
* Copyright (C) 2014 Maxime Ripard
* Maxime Ripard <maxime.ripard@free-electrons.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dmapool.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of_dma.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/slab.h>
#include <linux/types.h>
#include "virt-dma.h"
/*
* Common registers
*/
#define DMA_IRQ_EN(x) ((x) * 0x04)
#define DMA_IRQ_HALF BIT(0)
#define DMA_IRQ_PKG BIT(1)
#define DMA_IRQ_QUEUE BIT(2)
#define DMA_IRQ_CHAN_NR 8
#define DMA_IRQ_CHAN_WIDTH 4
#define DMA_IRQ_STAT(x) ((x) * 0x04 + 0x10)
#define DMA_STAT 0x30
/*
* sun8i specific registers
*/
#define SUN8I_DMA_GATE 0x20
#define SUN8I_DMA_GATE_ENABLE 0x4
/*
* Channels specific registers
*/
#define DMA_CHAN_ENABLE 0x00
#define DMA_CHAN_ENABLE_START BIT(0)
#define DMA_CHAN_ENABLE_STOP 0
#define DMA_CHAN_PAUSE 0x04
#define DMA_CHAN_PAUSE_PAUSE BIT(1)
#define DMA_CHAN_PAUSE_RESUME 0
#define DMA_CHAN_LLI_ADDR 0x08
#define DMA_CHAN_CUR_CFG 0x0c
#define DMA_CHAN_CFG_SRC_DRQ(x) ((x) & 0x1f)
#define DMA_CHAN_CFG_SRC_IO_MODE BIT(5)
#define DMA_CHAN_CFG_SRC_LINEAR_MODE (0 << 5)
#define DMA_CHAN_CFG_SRC_BURST(x) (((x) & 0x3) << 7)
#define DMA_CHAN_CFG_SRC_WIDTH(x) (((x) & 0x3) << 9)
#define DMA_CHAN_CFG_DST_DRQ(x) (DMA_CHAN_CFG_SRC_DRQ(x) << 16)
#define DMA_CHAN_CFG_DST_IO_MODE (DMA_CHAN_CFG_SRC_IO_MODE << 16)
#define DMA_CHAN_CFG_DST_LINEAR_MODE (DMA_CHAN_CFG_SRC_LINEAR_MODE << 16)
#define DMA_CHAN_CFG_DST_BURST(x) (DMA_CHAN_CFG_SRC_BURST(x) << 16)
#define DMA_CHAN_CFG_DST_WIDTH(x) (DMA_CHAN_CFG_SRC_WIDTH(x) << 16)
#define DMA_CHAN_CUR_SRC 0x10
#define DMA_CHAN_CUR_DST 0x14
#define DMA_CHAN_CUR_CNT 0x18
#define DMA_CHAN_CUR_PARA 0x1c
/*
* Various hardware related defines
*/
#define LLI_LAST_ITEM 0xfffff800
#define NORMAL_WAIT 8
#define DRQ_SDRAM 1
/*
* Hardware channels / ports representation
*
* The hardware is used in several SoCs, with differing numbers
* of channels and endpoints. This structure ties those numbers
* to a certain compatible string.
*/
struct sun6i_dma_config {
u32 nr_max_channels;
u32 nr_max_requests;
u32 nr_max_vchans;
};
/*
* Hardware representation of the LLI
*
* The hardware will be fed the physical address of this structure,
* and read its content in order to start the transfer.
*/
struct sun6i_dma_lli {
u32 cfg;
u32 src;
u32 dst;
u32 len;
u32 para;
u32 p_lli_next;
/*
* This field is not used by the DMA controller, but will be
* used by the CPU to go through the list (mostly for dumping
* or freeing it).
*/
struct sun6i_dma_lli *v_lli_next;
};
struct sun6i_desc {
struct virt_dma_desc vd;
dma_addr_t p_lli;
struct sun6i_dma_lli *v_lli;
};
struct sun6i_pchan {
u32 idx;
void __iomem *base;
struct sun6i_vchan *vchan;
struct sun6i_desc *desc;
struct sun6i_desc *done;
};
struct sun6i_vchan {
struct virt_dma_chan vc;
struct list_head node;
struct dma_slave_config cfg;
struct sun6i_pchan *phy;
u8 port;
};
struct sun6i_dma_dev {
struct dma_device slave;
void __iomem *base;
struct clk *clk;
int irq;
spinlock_t lock;
struct reset_control *rstc;
struct tasklet_struct task;
atomic_t tasklet_shutdown;
struct list_head pending;
struct dma_pool *pool;
struct sun6i_pchan *pchans;
struct sun6i_vchan *vchans;
const struct sun6i_dma_config *cfg;
};
static struct device *chan2dev(struct dma_chan *chan)
{
return &chan->dev->device;
}
static inline struct sun6i_dma_dev *to_sun6i_dma_dev(struct dma_device *d)
{
return container_of(d, struct sun6i_dma_dev, slave);
}
static inline struct sun6i_vchan *to_sun6i_vchan(struct dma_chan *chan)
{
return container_of(chan, struct sun6i_vchan, vc.chan);
}
static inline struct sun6i_desc *
to_sun6i_desc(struct dma_async_tx_descriptor *tx)
{
return container_of(tx, struct sun6i_desc, vd.tx);
}
static inline void sun6i_dma_dump_com_regs(struct sun6i_dma_dev *sdev)
{
dev_dbg(sdev->slave.dev, "Common register:\n"
"\tmask0(%04x): 0x%08x\n"
"\tmask1(%04x): 0x%08x\n"
"\tpend0(%04x): 0x%08x\n"
"\tpend1(%04x): 0x%08x\n"
"\tstats(%04x): 0x%08x\n",
DMA_IRQ_EN(0), readl(sdev->base + DMA_IRQ_EN(0)),
DMA_IRQ_EN(1), readl(sdev->base + DMA_IRQ_EN(1)),
DMA_IRQ_STAT(0), readl(sdev->base + DMA_IRQ_STAT(0)),
DMA_IRQ_STAT(1), readl(sdev->base + DMA_IRQ_STAT(1)),
DMA_STAT, readl(sdev->base + DMA_STAT));
}
static inline void sun6i_dma_dump_chan_regs(struct sun6i_dma_dev *sdev,
struct sun6i_pchan *pchan)
{
phys_addr_t reg = virt_to_phys(pchan->base);
dev_dbg(sdev->slave.dev, "Chan %d reg: %pa\n"
"\t___en(%04x): \t0x%08x\n"
"\tpause(%04x): \t0x%08x\n"
"\tstart(%04x): \t0x%08x\n"
"\t__cfg(%04x): \t0x%08x\n"
"\t__src(%04x): \t0x%08x\n"
"\t__dst(%04x): \t0x%08x\n"
"\tcount(%04x): \t0x%08x\n"
"\t_para(%04x): \t0x%08x\n\n",
pchan->idx, ®,
DMA_CHAN_ENABLE,
readl(pchan->base + DMA_CHAN_ENABLE),
DMA_CHAN_PAUSE,
readl(pchan->base + DMA_CHAN_PAUSE),
DMA_CHAN_LLI_ADDR,
readl(pchan->base + DMA_CHAN_LLI_ADDR),
DMA_CHAN_CUR_CFG,
readl(pchan->base + DMA_CHAN_CUR_CFG),
DMA_CHAN_CUR_SRC,
readl(pchan->base + DMA_CHAN_CUR_SRC),
DMA_CHAN_CUR_DST,
readl(pchan->base + DMA_CHAN_CUR_DST),
DMA_CHAN_CUR_CNT,
readl(pchan->base + DMA_CHAN_CUR_CNT),
DMA_CHAN_CUR_PARA,
readl(pchan->base + DMA_CHAN_CUR_PARA));
}
static inline s8 convert_burst(u32 maxburst)
{
switch (maxburst) {
case 1:
return 0;
case 8:
return 2;
default:
return -EINVAL;
}
}
static inline s8 convert_buswidth(enum dma_slave_buswidth addr_width)
{
if ((addr_width < DMA_SLAVE_BUSWIDTH_1_BYTE) ||
(addr_width > DMA_SLAVE_BUSWIDTH_4_BYTES))
return -EINVAL;
return addr_width >> 1;
}
static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev,
struct sun6i_dma_lli *next,
dma_addr_t next_phy,
struct sun6i_desc *txd)
{
if ((!prev && !txd) || !next)
return NULL;
if (!prev) {
txd->p_lli = next_phy;
txd->v_lli = next;
} else {
prev->p_lli_next = next_phy;
prev->v_lli_next = next;
}
next->p_lli_next = LLI_LAST_ITEM;
next->v_lli_next = NULL;
return next;
}
static inline int sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli,
dma_addr_t src,
dma_addr_t dst, u32 len,
struct dma_slave_config *config)
{
u8 src_width, dst_width, src_burst, dst_burst;
if (!config)
return -EINVAL;
src_burst = convert_burst(config->src_maxburst);
if (src_burst)
return src_burst;
dst_burst = convert_burst(config->dst_maxburst);
if (dst_burst)
return dst_burst;
src_width = convert_buswidth(config->src_addr_width);
if (src_width)
return src_width;
dst_width = convert_buswidth(config->dst_addr_width);
if (dst_width)
return dst_width;
lli->cfg = DMA_CHAN_CFG_SRC_BURST(src_burst) |
DMA_CHAN_CFG_SRC_WIDTH(src_width) |
DMA_CHAN_CFG_DST_BURST(dst_burst) |
DMA_CHAN_CFG_DST_WIDTH(dst_width);
lli->src = src;
lli->dst = dst;
lli->len = len;
lli->para = NORMAL_WAIT;
return 0;
}
static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan,
struct sun6i_dma_lli *lli)
{
phys_addr_t p_lli = virt_to_phys(lli);
dev_dbg(chan2dev(&vchan->vc.chan),
"\n\tdesc: p - %pa v - 0x%p\n"
"\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n"
"\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n",
&p_lli, lli,
lli->cfg, lli->src, lli->dst,
lli->len, lli->para, lli->p_lli_next);
}
static void sun6i_dma_free_desc(struct virt_dma_desc *vd)
{
struct sun6i_desc *txd = to_sun6i_desc(&vd->tx);
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device);
struct sun6i_dma_lli *v_lli, *v_next;
dma_addr_t p_lli, p_next;
if (unlikely(!txd))
return;
p_lli = txd->p_lli;
v_lli = txd->v_lli;
while (v_lli) {
v_next = v_lli->v_lli_next;
p_next = v_lli->p_lli_next;
dma_pool_free(sdev->pool, v_lli, p_lli);
v_lli = v_next;
p_lli = p_next;
}
kfree(txd);
}
static int sun6i_dma_start_desc(struct sun6i_vchan *vchan)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device);
struct virt_dma_desc *desc = vchan_next_desc(&vchan->vc);
struct sun6i_pchan *pchan = vchan->phy;
u32 irq_val, irq_reg, irq_offset;
if (!pchan)
return -EAGAIN;
if (!desc) {
pchan->desc = NULL;
pchan->done = NULL;
return -EAGAIN;
}
list_del(&desc->node);
pchan->desc = to_sun6i_desc(&desc->tx);
pchan->done = NULL;
sun6i_dma_dump_lli(vchan, pchan->desc->v_lli);
irq_reg = pchan->idx / DMA_IRQ_CHAN_NR;
irq_offset = pchan->idx % DMA_IRQ_CHAN_NR;
irq_val = readl(sdev->base + DMA_IRQ_EN(irq_offset));
irq_val |= DMA_IRQ_QUEUE << (irq_offset * DMA_IRQ_CHAN_WIDTH);
writel(irq_val, sdev->base + DMA_IRQ_EN(irq_offset));
writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR);
writel(DMA_CHAN_ENABLE_START, pchan->base + DMA_CHAN_ENABLE);
sun6i_dma_dump_com_regs(sdev);
sun6i_dma_dump_chan_regs(sdev, pchan);
return 0;
}
static void sun6i_dma_tasklet(unsigned long data)
{
struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)data;
const struct sun6i_dma_config *cfg = sdev->cfg;
struct sun6i_vchan *vchan;
struct sun6i_pchan *pchan;
unsigned int pchan_alloc = 0;
unsigned int pchan_idx;
list_for_each_entry(vchan, &sdev->slave.channels, vc.chan.device_node) {
spin_lock_irq(&vchan->vc.lock);
pchan = vchan->phy;
if (pchan && pchan->done) {
if (sun6i_dma_start_desc(vchan)) {
/*
* No current txd associated with this channel
*/
dev_dbg(sdev->slave.dev, "pchan %u: free\n",
pchan->idx);
/* Mark this channel free */
vchan->phy = NULL;
pchan->vchan = NULL;
}
}
spin_unlock_irq(&vchan->vc.lock);
}
spin_lock_irq(&sdev->lock);
for (pchan_idx = 0; pchan_idx < cfg->nr_max_channels; pchan_idx++) {
pchan = &sdev->pchans[pchan_idx];
if (pchan->vchan || list_empty(&sdev->pending))
continue;
vchan = list_first_entry(&sdev->pending,
struct sun6i_vchan, node);
/* Remove from pending channels */
list_del_init(&vchan->node);
pchan_alloc |= BIT(pchan_idx);
/* Mark this channel allocated */
pchan->vchan = vchan;
vchan->phy = pchan;
dev_dbg(sdev->slave.dev, "pchan %u: alloc vchan %p\n",
pchan->idx, &vchan->vc);
}
spin_unlock_irq(&sdev->lock);
for (pchan_idx = 0; pchan_idx < cfg->nr_max_channels; pchan_idx++) {
if (!(pchan_alloc & BIT(pchan_idx)))
continue;
pchan = sdev->pchans + pchan_idx;
vchan = pchan->vchan;
if (vchan) {
spin_lock_irq(&vchan->vc.lock);
sun6i_dma_start_desc(vchan);
spin_unlock_irq(&vchan->vc.lock);
}
}
}
static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id)
{
struct sun6i_dma_dev *sdev = dev_id;
struct sun6i_vchan *vchan;
struct sun6i_pchan *pchan;
int i, j, ret = IRQ_NONE;
u32 status;
for (i = 0; i < sdev->cfg->nr_max_channels / DMA_IRQ_CHAN_NR; i++) {
status = readl(sdev->base + DMA_IRQ_STAT(i));
if (!status)
continue;
dev_dbg(sdev->slave.dev, "DMA irq status %s: 0x%x\n",
i ? "high" : "low", status);
writel(status, sdev->base + DMA_IRQ_STAT(i));
for (j = 0; (j < DMA_IRQ_CHAN_NR) && status; j++) {
if (status & DMA_IRQ_QUEUE) {
pchan = sdev->pchans + j;
vchan = pchan->vchan;
if (vchan) {
spin_lock(&vchan->vc.lock);
vchan_cookie_complete(&pchan->desc->vd);
pchan->done = pchan->desc;
spin_unlock(&vchan->vc.lock);
}
}
status = status >> DMA_IRQ_CHAN_WIDTH;
}
if (!atomic_read(&sdev->tasklet_shutdown))
tasklet_schedule(&sdev->task);
ret = IRQ_HANDLED;
}
return ret;
}
static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy(
struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
size_t len, unsigned long flags)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct sun6i_dma_lli *v_lli;
struct sun6i_desc *txd;
dma_addr_t p_lli;
s8 burst, width;
dev_dbg(chan2dev(chan),
"%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n",
__func__, vchan->vc.chan.chan_id, &dest, &src, len, flags);
if (!len)
return NULL;
txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
if (!txd)
return NULL;
v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
if (!v_lli) {
dev_err(sdev->slave.dev, "Failed to alloc lli memory\n");
goto err_txd_free;
}
v_lli->src = src;
v_lli->dst = dest;
v_lli->len = len;
v_lli->para = NORMAL_WAIT;
burst = convert_burst(8);
width = convert_buswidth(DMA_SLAVE_BUSWIDTH_4_BYTES);
v_lli->cfg |= DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
DMA_CHAN_CFG_DST_LINEAR_MODE |
DMA_CHAN_CFG_SRC_LINEAR_MODE |
DMA_CHAN_CFG_SRC_BURST(burst) |
DMA_CHAN_CFG_SRC_WIDTH(width) |
DMA_CHAN_CFG_DST_BURST(burst) |
DMA_CHAN_CFG_DST_WIDTH(width);
sun6i_dma_lli_add(NULL, v_lli, p_lli, txd);
sun6i_dma_dump_lli(vchan, v_lli);
return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
err_txd_free:
kfree(txd);
return NULL;
}
static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl,
unsigned int sg_len, enum dma_transfer_direction dir,
unsigned long flags, void *context)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct dma_slave_config *sconfig = &vchan->cfg;
struct sun6i_dma_lli *v_lli, *prev = NULL;
struct sun6i_desc *txd;
struct scatterlist *sg;
dma_addr_t p_lli;
int i, ret;
if (!sgl)
return NULL;
if (!is_slave_direction(dir)) {
dev_err(chan2dev(chan), "Invalid DMA direction\n");
return NULL;
}
txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
if (!txd)
return NULL;
for_each_sg(sgl, sg, sg_len, i) {
v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
if (!v_lli)
goto err_lli_free;
if (dir == DMA_MEM_TO_DEV) {
ret = sun6i_dma_cfg_lli(v_lli, sg_dma_address(sg),
sconfig->dst_addr, sg_dma_len(sg),
sconfig);
if (ret)
goto err_cur_lli_free;
v_lli->cfg |= DMA_CHAN_CFG_DST_IO_MODE |
DMA_CHAN_CFG_SRC_LINEAR_MODE |
DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
DMA_CHAN_CFG_DST_DRQ(vchan->port);
dev_dbg(chan2dev(chan),
"%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
__func__, vchan->vc.chan.chan_id,
&sconfig->dst_addr, &sg_dma_address(sg),
sg_dma_len(sg), flags);
} else {
ret = sun6i_dma_cfg_lli(v_lli, sconfig->src_addr,
sg_dma_address(sg), sg_dma_len(sg),
sconfig);
if (ret)
goto err_cur_lli_free;
v_lli->cfg |= DMA_CHAN_CFG_DST_LINEAR_MODE |
DMA_CHAN_CFG_SRC_IO_MODE |
DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
DMA_CHAN_CFG_SRC_DRQ(vchan->port);
dev_dbg(chan2dev(chan),
"%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
__func__, vchan->vc.chan.chan_id,
&sg_dma_address(sg), &sconfig->src_addr,
sg_dma_len(sg), flags);
}
prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd);
}
dev_dbg(chan2dev(chan), "First: %pad\n", &txd->p_lli);
for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
sun6i_dma_dump_lli(vchan, prev);
return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
err_cur_lli_free:
dma_pool_free(sdev->pool, v_lli, p_lli);
err_lli_free:
for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
kfree(txd);
return NULL;
}
static int sun6i_dma_config(struct dma_chan *chan,
struct dma_slave_config *config)
{
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
memcpy(&vchan->cfg, config, sizeof(*config));
return 0;
}
static int sun6i_dma_pause(struct dma_chan *chan)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct sun6i_pchan *pchan = vchan->phy;
dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc);
if (pchan) {
writel(DMA_CHAN_PAUSE_PAUSE,
pchan->base + DMA_CHAN_PAUSE);
} else {
spin_lock(&sdev->lock);
list_del_init(&vchan->node);
spin_unlock(&sdev->lock);
}
return 0;
}
static int sun6i_dma_resume(struct dma_chan *chan)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct sun6i_pchan *pchan = vchan->phy;
unsigned long flags;
dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc);
spin_lock_irqsave(&vchan->vc.lock, flags);
if (pchan) {
writel(DMA_CHAN_PAUSE_RESUME,
pchan->base + DMA_CHAN_PAUSE);
} else if (!list_empty(&vchan->vc.desc_issued)) {
spin_lock(&sdev->lock);
list_add_tail(&vchan->node, &sdev->pending);
spin_unlock(&sdev->lock);
}
spin_unlock_irqrestore(&vchan->vc.lock, flags);
return 0;
}
static int sun6i_dma_terminate_all(struct dma_chan *chan)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct sun6i_pchan *pchan = vchan->phy;
unsigned long flags;
LIST_HEAD(head);
spin_lock(&sdev->lock);
list_del_init(&vchan->node);
spin_unlock(&sdev->lock);
spin_lock_irqsave(&vchan->vc.lock, flags);
vchan_get_all_descriptors(&vchan->vc, &head);
if (pchan) {
writel(DMA_CHAN_ENABLE_STOP, pchan->base + DMA_CHAN_ENABLE);
writel(DMA_CHAN_PAUSE_RESUME, pchan->base + DMA_CHAN_PAUSE);
vchan->phy = NULL;
pchan->vchan = NULL;
pchan->desc = NULL;
pchan->done = NULL;
}
spin_unlock_irqrestore(&vchan->vc.lock, flags);
vchan_dma_desc_free_list(&vchan->vc, &head);
return 0;
}
static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan,
dma_cookie_t cookie,
struct dma_tx_state *state)
{
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct sun6i_pchan *pchan = vchan->phy;
struct sun6i_dma_lli *lli;
struct virt_dma_desc *vd;
struct sun6i_desc *txd;
enum dma_status ret;
unsigned long flags;
size_t bytes = 0;
ret = dma_cookie_status(chan, cookie, state);
if (ret == DMA_COMPLETE)
return ret;
spin_lock_irqsave(&vchan->vc.lock, flags);
vd = vchan_find_desc(&vchan->vc, cookie);
txd = to_sun6i_desc(&vd->tx);
if (vd) {
for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next)
bytes += lli->len;
} else if (!pchan || !pchan->desc) {
bytes = 0;
} else {
bytes = readl(pchan->base + DMA_CHAN_CUR_CNT);
}
spin_unlock_irqrestore(&vchan->vc.lock, flags);
dma_set_residue(state, bytes);
return ret;
}
static void sun6i_dma_issue_pending(struct dma_chan *chan)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
unsigned long flags;
spin_lock_irqsave(&vchan->vc.lock, flags);
if (vchan_issue_pending(&vchan->vc)) {
spin_lock(&sdev->lock);
if (!vchan->phy && list_empty(&vchan->node)) {
list_add_tail(&vchan->node, &sdev->pending);
tasklet_schedule(&sdev->task);
dev_dbg(chan2dev(chan), "vchan %p: issued\n",
&vchan->vc);
}
spin_unlock(&sdev->lock);
} else {
dev_dbg(chan2dev(chan), "vchan %p: nothing to issue\n",
&vchan->vc);
}
spin_unlock_irqrestore(&vchan->vc.lock, flags);
}
static void sun6i_dma_free_chan_resources(struct dma_chan *chan)
{
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
unsigned long flags;
spin_lock_irqsave(&sdev->lock, flags);
list_del_init(&vchan->node);
spin_unlock_irqrestore(&sdev->lock, flags);
vchan_free_chan_resources(&vchan->vc);
}
static struct dma_chan *sun6i_dma_of_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct sun6i_dma_dev *sdev = ofdma->of_dma_data;
struct sun6i_vchan *vchan;
struct dma_chan *chan;
u8 port = dma_spec->args[0];
if (port > sdev->cfg->nr_max_requests)
return NULL;
chan = dma_get_any_slave_channel(&sdev->slave);
if (!chan)
return NULL;
vchan = to_sun6i_vchan(chan);
vchan->port = port;
return chan;
}
static inline void sun6i_kill_tasklet(struct sun6i_dma_dev *sdev)
{
/* Disable all interrupts from DMA */
writel(0, sdev->base + DMA_IRQ_EN(0));
writel(0, sdev->base + DMA_IRQ_EN(1));
/* Prevent spurious interrupts from scheduling the tasklet */
atomic_inc(&sdev->tasklet_shutdown);
/* Make sure we won't have any further interrupts */
devm_free_irq(sdev->slave.dev, sdev->irq, sdev);
/* Actually prevent the tasklet from being scheduled */
tasklet_kill(&sdev->task);
}
static inline void sun6i_dma_free(struct sun6i_dma_dev *sdev)
{
int i;
for (i = 0; i < sdev->cfg->nr_max_vchans; i++) {
struct sun6i_vchan *vchan = &sdev->vchans[i];
list_del(&vchan->vc.chan.device_node);
tasklet_kill(&vchan->vc.task);
}
}
/*
* For A31:
*
* There's 16 physical channels that can work in parallel.
*
* However we have 30 different endpoints for our requests.
*
* Since the channels are able to handle only an unidirectional
* transfer, we need to allocate more virtual channels so that
* everyone can grab one channel.
*
* Some devices can't work in both direction (mostly because it
* wouldn't make sense), so we have a bit fewer virtual channels than
* 2 channels per endpoints.
*/
static struct sun6i_dma_config sun6i_a31_dma_cfg = {
.nr_max_channels = 16,
.nr_max_requests = 30,
.nr_max_vchans = 53,
};
/*
* The A23 only has 8 physical channels, a maximum DRQ port id of 24,
* and a total of 37 usable source and destination endpoints.
*/
static struct sun6i_dma_config sun8i_a23_dma_cfg = {
.nr_max_channels = 8,
.nr_max_requests = 24,
.nr_max_vchans = 37,
};
/*
* The H3 has 12 physical channels, a maximum DRQ port id of 27,
* and a total of 34 usable source and destination endpoints.
*/
static struct sun6i_dma_config sun8i_h3_dma_cfg = {
.nr_max_channels = 12,
.nr_max_requests = 27,
.nr_max_vchans = 34,
};
static const struct of_device_id sun6i_dma_match[] = {
{ .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg },
{ .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg },
{ .compatible = "allwinner,sun8i-h3-dma", .data = &sun8i_h3_dma_cfg },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sun6i_dma_match);
static int sun6i_dma_probe(struct platform_device *pdev)
{
const struct of_device_id *device;
struct sun6i_dma_dev *sdc;
struct resource *res;
int ret, i;
sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL);
if (!sdc)
return -ENOMEM;
device = of_match_device(sun6i_dma_match, &pdev->dev);
if (!device)
return -ENODEV;
sdc->cfg = device->data;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
sdc->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(sdc->base))
return PTR_ERR(sdc->base);
sdc->irq = platform_get_irq(pdev, 0);
if (sdc->irq < 0) {
dev_err(&pdev->dev, "Cannot claim IRQ\n");
return sdc->irq;
}
sdc->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(sdc->clk)) {
dev_err(&pdev->dev, "No clock specified\n");
return PTR_ERR(sdc->clk);
}
sdc->rstc = devm_reset_control_get(&pdev->dev, NULL);
if (IS_ERR(sdc->rstc)) {
dev_err(&pdev->dev, "No reset controller specified\n");
return PTR_ERR(sdc->rstc);
}
sdc->pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
sizeof(struct sun6i_dma_lli), 4, 0);
if (!sdc->pool) {
dev_err(&pdev->dev, "No memory for descriptors dma pool\n");
return -ENOMEM;
}
platform_set_drvdata(pdev, sdc);
INIT_LIST_HEAD(&sdc->pending);
spin_lock_init(&sdc->lock);
dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask);
dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask);
dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask);
INIT_LIST_HEAD(&sdc->slave.channels);
sdc->slave.device_free_chan_resources = sun6i_dma_free_chan_resources;
sdc->slave.device_tx_status = sun6i_dma_tx_status;
sdc->slave.device_issue_pending = sun6i_dma_issue_pending;
sdc->slave.device_prep_slave_sg = sun6i_dma_prep_slave_sg;
sdc->slave.device_prep_dma_memcpy = sun6i_dma_prep_dma_memcpy;
sdc->slave.copy_align = DMAENGINE_ALIGN_4_BYTES;
sdc->slave.device_config = sun6i_dma_config;
sdc->slave.device_pause = sun6i_dma_pause;
sdc->slave.device_resume = sun6i_dma_resume;
sdc->slave.device_terminate_all = sun6i_dma_terminate_all;
sdc->slave.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
sdc->slave.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
sdc->slave.directions = BIT(DMA_DEV_TO_MEM) |
BIT(DMA_MEM_TO_DEV);
sdc->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
sdc->slave.dev = &pdev->dev;
sdc->pchans = devm_kcalloc(&pdev->dev, sdc->cfg->nr_max_channels,
sizeof(struct sun6i_pchan), GFP_KERNEL);
if (!sdc->pchans)
return -ENOMEM;
sdc->vchans = devm_kcalloc(&pdev->dev, sdc->cfg->nr_max_vchans,
sizeof(struct sun6i_vchan), GFP_KERNEL);
if (!sdc->vchans)
return -ENOMEM;
tasklet_init(&sdc->task, sun6i_dma_tasklet, (unsigned long)sdc);
for (i = 0; i < sdc->cfg->nr_max_channels; i++) {
struct sun6i_pchan *pchan = &sdc->pchans[i];
pchan->idx = i;
pchan->base = sdc->base + 0x100 + i * 0x40;
}
for (i = 0; i < sdc->cfg->nr_max_vchans; i++) {
struct sun6i_vchan *vchan = &sdc->vchans[i];
INIT_LIST_HEAD(&vchan->node);
vchan->vc.desc_free = sun6i_dma_free_desc;
vchan_init(&vchan->vc, &sdc->slave);
}
ret = reset_control_deassert(sdc->rstc);
if (ret) {
dev_err(&pdev->dev, "Couldn't deassert the device from reset\n");
goto err_chan_free;
}
ret = clk_prepare_enable(sdc->clk);
if (ret) {
dev_err(&pdev->dev, "Couldn't enable the clock\n");
goto err_reset_assert;
}
ret = devm_request_irq(&pdev->dev, sdc->irq, sun6i_dma_interrupt, 0,
dev_name(&pdev->dev), sdc);
if (ret) {
dev_err(&pdev->dev, "Cannot request IRQ\n");
goto err_clk_disable;
}
ret = dma_async_device_register(&sdc->slave);
if (ret) {
dev_warn(&pdev->dev, "Failed to register DMA engine device\n");
goto err_irq_disable;
}
ret = of_dma_controller_register(pdev->dev.of_node, sun6i_dma_of_xlate,
sdc);
if (ret) {
dev_err(&pdev->dev, "of_dma_controller_register failed\n");
goto err_dma_unregister;
}
/*
* sun8i variant requires us to toggle a dma gating register,
* as seen in Allwinner's SDK. This register is not documented
* in the A23 user manual.
*/
if (of_device_is_compatible(pdev->dev.of_node,
"allwinner,sun8i-a23-dma"))
writel(SUN8I_DMA_GATE_ENABLE, sdc->base + SUN8I_DMA_GATE);
return 0;
err_dma_unregister:
dma_async_device_unregister(&sdc->slave);
err_irq_disable:
sun6i_kill_tasklet(sdc);
err_clk_disable:
clk_disable_unprepare(sdc->clk);
err_reset_assert:
reset_control_assert(sdc->rstc);
err_chan_free:
sun6i_dma_free(sdc);
return ret;
}
static int sun6i_dma_remove(struct platform_device *pdev)
{
struct sun6i_dma_dev *sdc = platform_get_drvdata(pdev);
of_dma_controller_free(pdev->dev.of_node);
dma_async_device_unregister(&sdc->slave);
sun6i_kill_tasklet(sdc);
clk_disable_unprepare(sdc->clk);
reset_control_assert(sdc->rstc);
sun6i_dma_free(sdc);
return 0;
}
static struct platform_driver sun6i_dma_driver = {
.probe = sun6i_dma_probe,
.remove = sun6i_dma_remove,
.driver = {
.name = "sun6i-dma",
.of_match_table = sun6i_dma_match,
},
};
module_platform_driver(sun6i_dma_driver);
MODULE_DESCRIPTION("Allwinner A31 DMA Controller Driver");
MODULE_AUTHOR("Sugar <shuge@allwinnertech.com>");
MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
MODULE_LICENSE("GPL");