linux/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
Colin Ian King eda38ce482 dmaengine: dw-axi-dmac: remove redundant null check on desc
The pointer desc is being null checked twice, the second null check
is redundant because desc has not been re-assigned between the
checks. Remove the redundant second null check on desc.

Fixes: ef6fb2d6f1 ("dmaengine: dw-axi-dmac: simplify descriptor management")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Tested-by: Sia Jee Heng <jee.heng.sia@intel.com>
Reviewed-by: Sia Jee Heng <jee.heng.sia@intel.com>
Addresses-Coverity: ("Logically dead code")
Link: https://lore.kernel.org/r/20210203134652.22618-1-colin.king@canonical.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-02-08 17:39:39 +05:30

1516 lines
38 KiB
C

// SPDX-License-Identifier: GPL-2.0
// (C) 2017-2018 Synopsys, Inc. (www.synopsys.com)
/*
* Synopsys DesignWare AXI DMA Controller driver.
*
* Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dmaengine.h>
#include <linux/dmapool.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/types.h>
#include "dw-axi-dmac.h"
#include "../dmaengine.h"
#include "../virt-dma.h"
/*
* The set of bus widths supported by the DMA controller. DW AXI DMAC supports
* master data bus width up to 512 bits (for both AXI master interfaces), but
* it depends on IP block configurarion.
*/
#define AXI_DMA_BUSWIDTHS \
(DMA_SLAVE_BUSWIDTH_1_BYTE | \
DMA_SLAVE_BUSWIDTH_2_BYTES | \
DMA_SLAVE_BUSWIDTH_4_BYTES | \
DMA_SLAVE_BUSWIDTH_8_BYTES | \
DMA_SLAVE_BUSWIDTH_16_BYTES | \
DMA_SLAVE_BUSWIDTH_32_BYTES | \
DMA_SLAVE_BUSWIDTH_64_BYTES)
static inline void
axi_dma_iowrite32(struct axi_dma_chip *chip, u32 reg, u32 val)
{
iowrite32(val, chip->regs + reg);
}
static inline u32 axi_dma_ioread32(struct axi_dma_chip *chip, u32 reg)
{
return ioread32(chip->regs + reg);
}
static inline void
axi_chan_iowrite32(struct axi_dma_chan *chan, u32 reg, u32 val)
{
iowrite32(val, chan->chan_regs + reg);
}
static inline u32 axi_chan_ioread32(struct axi_dma_chan *chan, u32 reg)
{
return ioread32(chan->chan_regs + reg);
}
static inline void
axi_chan_iowrite64(struct axi_dma_chan *chan, u32 reg, u64 val)
{
/*
* We split one 64 bit write for two 32 bit write as some HW doesn't
* support 64 bit access.
*/
iowrite32(lower_32_bits(val), chan->chan_regs + reg);
iowrite32(upper_32_bits(val), chan->chan_regs + reg + 4);
}
static inline void axi_dma_disable(struct axi_dma_chip *chip)
{
u32 val;
val = axi_dma_ioread32(chip, DMAC_CFG);
val &= ~DMAC_EN_MASK;
axi_dma_iowrite32(chip, DMAC_CFG, val);
}
static inline void axi_dma_enable(struct axi_dma_chip *chip)
{
u32 val;
val = axi_dma_ioread32(chip, DMAC_CFG);
val |= DMAC_EN_MASK;
axi_dma_iowrite32(chip, DMAC_CFG, val);
}
static inline void axi_dma_irq_disable(struct axi_dma_chip *chip)
{
u32 val;
val = axi_dma_ioread32(chip, DMAC_CFG);
val &= ~INT_EN_MASK;
axi_dma_iowrite32(chip, DMAC_CFG, val);
}
static inline void axi_dma_irq_enable(struct axi_dma_chip *chip)
{
u32 val;
val = axi_dma_ioread32(chip, DMAC_CFG);
val |= INT_EN_MASK;
axi_dma_iowrite32(chip, DMAC_CFG, val);
}
static inline void axi_chan_irq_disable(struct axi_dma_chan *chan, u32 irq_mask)
{
u32 val;
if (likely(irq_mask == DWAXIDMAC_IRQ_ALL)) {
axi_chan_iowrite32(chan, CH_INTSTATUS_ENA, DWAXIDMAC_IRQ_NONE);
} else {
val = axi_chan_ioread32(chan, CH_INTSTATUS_ENA);
val &= ~irq_mask;
axi_chan_iowrite32(chan, CH_INTSTATUS_ENA, val);
}
}
static inline void axi_chan_irq_set(struct axi_dma_chan *chan, u32 irq_mask)
{
axi_chan_iowrite32(chan, CH_INTSTATUS_ENA, irq_mask);
}
static inline void axi_chan_irq_sig_set(struct axi_dma_chan *chan, u32 irq_mask)
{
axi_chan_iowrite32(chan, CH_INTSIGNAL_ENA, irq_mask);
}
static inline void axi_chan_irq_clear(struct axi_dma_chan *chan, u32 irq_mask)
{
axi_chan_iowrite32(chan, CH_INTCLEAR, irq_mask);
}
static inline u32 axi_chan_irq_read(struct axi_dma_chan *chan)
{
return axi_chan_ioread32(chan, CH_INTSTATUS);
}
static inline void axi_chan_disable(struct axi_dma_chan *chan)
{
u32 val;
val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
val &= ~(BIT(chan->id) << DMAC_CHAN_EN_SHIFT);
val |= BIT(chan->id) << DMAC_CHAN_EN_WE_SHIFT;
axi_dma_iowrite32(chan->chip, DMAC_CHEN, val);
}
static inline void axi_chan_enable(struct axi_dma_chan *chan)
{
u32 val;
val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
val |= BIT(chan->id) << DMAC_CHAN_EN_SHIFT |
BIT(chan->id) << DMAC_CHAN_EN_WE_SHIFT;
axi_dma_iowrite32(chan->chip, DMAC_CHEN, val);
}
static inline bool axi_chan_is_hw_enable(struct axi_dma_chan *chan)
{
u32 val;
val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
return !!(val & (BIT(chan->id) << DMAC_CHAN_EN_SHIFT));
}
static void axi_dma_hw_init(struct axi_dma_chip *chip)
{
u32 i;
for (i = 0; i < chip->dw->hdata->nr_channels; i++) {
axi_chan_irq_disable(&chip->dw->chan[i], DWAXIDMAC_IRQ_ALL);
axi_chan_disable(&chip->dw->chan[i]);
}
}
static u32 axi_chan_get_xfer_width(struct axi_dma_chan *chan, dma_addr_t src,
dma_addr_t dst, size_t len)
{
u32 max_width = chan->chip->dw->hdata->m_data_width;
return __ffs(src | dst | len | BIT(max_width));
}
static inline const char *axi_chan_name(struct axi_dma_chan *chan)
{
return dma_chan_name(&chan->vc.chan);
}
static struct axi_dma_desc *axi_desc_alloc(u32 num)
{
struct axi_dma_desc *desc;
desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
if (!desc)
return NULL;
desc->hw_desc = kcalloc(num, sizeof(*desc->hw_desc), GFP_NOWAIT);
if (!desc->hw_desc) {
kfree(desc);
return NULL;
}
return desc;
}
static struct axi_dma_lli *axi_desc_get(struct axi_dma_chan *chan,
dma_addr_t *addr)
{
struct axi_dma_lli *lli;
dma_addr_t phys;
lli = dma_pool_zalloc(chan->desc_pool, GFP_NOWAIT, &phys);
if (unlikely(!lli)) {
dev_err(chan2dev(chan), "%s: not enough descriptors available\n",
axi_chan_name(chan));
return NULL;
}
atomic_inc(&chan->descs_allocated);
*addr = phys;
return lli;
}
static void axi_desc_put(struct axi_dma_desc *desc)
{
struct axi_dma_chan *chan = desc->chan;
int count = atomic_read(&chan->descs_allocated);
struct axi_dma_hw_desc *hw_desc;
int descs_put;
for (descs_put = 0; descs_put < count; descs_put++) {
hw_desc = &desc->hw_desc[descs_put];
dma_pool_free(chan->desc_pool, hw_desc->lli, hw_desc->llp);
}
kfree(desc->hw_desc);
kfree(desc);
atomic_sub(descs_put, &chan->descs_allocated);
dev_vdbg(chan2dev(chan), "%s: %d descs put, %d still allocated\n",
axi_chan_name(chan), descs_put,
atomic_read(&chan->descs_allocated));
}
static void vchan_desc_put(struct virt_dma_desc *vdesc)
{
axi_desc_put(vd_to_axi_desc(vdesc));
}
static enum dma_status
dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
struct virt_dma_desc *vdesc;
enum dma_status status;
u32 completed_length;
unsigned long flags;
u32 completed_blocks;
size_t bytes = 0;
u32 length;
u32 len;
status = dma_cookie_status(dchan, cookie, txstate);
if (status == DMA_COMPLETE || !txstate)
return status;
spin_lock_irqsave(&chan->vc.lock, flags);
vdesc = vchan_find_desc(&chan->vc, cookie);
if (vdesc) {
length = vd_to_axi_desc(vdesc)->length;
completed_blocks = vd_to_axi_desc(vdesc)->completed_blocks;
len = vd_to_axi_desc(vdesc)->hw_desc[0].len;
completed_length = completed_blocks * len;
bytes = length - completed_length;
} else {
bytes = vd_to_axi_desc(vdesc)->length;
}
spin_unlock_irqrestore(&chan->vc.lock, flags);
dma_set_residue(txstate, bytes);
return status;
}
static void write_desc_llp(struct axi_dma_hw_desc *desc, dma_addr_t adr)
{
desc->lli->llp = cpu_to_le64(adr);
}
static void write_chan_llp(struct axi_dma_chan *chan, dma_addr_t adr)
{
axi_chan_iowrite64(chan, CH_LLP, adr);
}
static void dw_axi_dma_set_byte_halfword(struct axi_dma_chan *chan, bool set)
{
u32 offset = DMAC_APB_BYTE_WR_CH_EN;
u32 reg_width, val;
if (!chan->chip->apb_regs) {
dev_dbg(chan->chip->dev, "apb_regs not initialized\n");
return;
}
reg_width = __ffs(chan->config.dst_addr_width);
if (reg_width == DWAXIDMAC_TRANS_WIDTH_16)
offset = DMAC_APB_HALFWORD_WR_CH_EN;
val = ioread32(chan->chip->apb_regs + offset);
if (set)
val |= BIT(chan->id);
else
val &= ~BIT(chan->id);
iowrite32(val, chan->chip->apb_regs + offset);
}
/* Called in chan locked context */
static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
struct axi_dma_desc *first)
{
u32 priority = chan->chip->dw->hdata->priority[chan->id];
u32 reg, irq_mask;
u8 lms = 0; /* Select AXI0 master for LLI fetching */
if (unlikely(axi_chan_is_hw_enable(chan))) {
dev_err(chan2dev(chan), "%s is non-idle!\n",
axi_chan_name(chan));
return;
}
axi_dma_enable(chan->chip);
reg = (DWAXIDMAC_MBLK_TYPE_LL << CH_CFG_L_DST_MULTBLK_TYPE_POS |
DWAXIDMAC_MBLK_TYPE_LL << CH_CFG_L_SRC_MULTBLK_TYPE_POS);
axi_chan_iowrite32(chan, CH_CFG_L, reg);
reg = (DWAXIDMAC_TT_FC_MEM_TO_MEM_DMAC << CH_CFG_H_TT_FC_POS |
priority << CH_CFG_H_PRIORITY_POS |
DWAXIDMAC_HS_SEL_HW << CH_CFG_H_HS_SEL_DST_POS |
DWAXIDMAC_HS_SEL_HW << CH_CFG_H_HS_SEL_SRC_POS);
switch (chan->direction) {
case DMA_MEM_TO_DEV:
dw_axi_dma_set_byte_halfword(chan, true);
reg |= (chan->config.device_fc ?
DWAXIDMAC_TT_FC_MEM_TO_PER_DST :
DWAXIDMAC_TT_FC_MEM_TO_PER_DMAC)
<< CH_CFG_H_TT_FC_POS;
break;
case DMA_DEV_TO_MEM:
reg |= (chan->config.device_fc ?
DWAXIDMAC_TT_FC_PER_TO_MEM_SRC :
DWAXIDMAC_TT_FC_PER_TO_MEM_DMAC)
<< CH_CFG_H_TT_FC_POS;
break;
default:
break;
}
axi_chan_iowrite32(chan, CH_CFG_H, reg);
write_chan_llp(chan, first->hw_desc[0].llp | lms);
irq_mask = DWAXIDMAC_IRQ_DMA_TRF | DWAXIDMAC_IRQ_ALL_ERR;
axi_chan_irq_sig_set(chan, irq_mask);
/* Generate 'suspend' status but don't generate interrupt */
irq_mask |= DWAXIDMAC_IRQ_SUSPENDED;
axi_chan_irq_set(chan, irq_mask);
axi_chan_enable(chan);
}
static void axi_chan_start_first_queued(struct axi_dma_chan *chan)
{
struct axi_dma_desc *desc;
struct virt_dma_desc *vd;
vd = vchan_next_desc(&chan->vc);
if (!vd)
return;
desc = vd_to_axi_desc(vd);
dev_vdbg(chan2dev(chan), "%s: started %u\n", axi_chan_name(chan),
vd->tx.cookie);
axi_chan_block_xfer_start(chan, desc);
}
static void dma_chan_issue_pending(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
unsigned long flags;
spin_lock_irqsave(&chan->vc.lock, flags);
if (vchan_issue_pending(&chan->vc))
axi_chan_start_first_queued(chan);
spin_unlock_irqrestore(&chan->vc.lock, flags);
}
static void dw_axi_dma_synchronize(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
vchan_synchronize(&chan->vc);
}
static int dma_chan_alloc_chan_resources(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
/* ASSERT: channel is idle */
if (axi_chan_is_hw_enable(chan)) {
dev_err(chan2dev(chan), "%s is non-idle!\n",
axi_chan_name(chan));
return -EBUSY;
}
/* LLI address must be aligned to a 64-byte boundary */
chan->desc_pool = dma_pool_create(dev_name(chan2dev(chan)),
chan->chip->dev,
sizeof(struct axi_dma_lli),
64, 0);
if (!chan->desc_pool) {
dev_err(chan2dev(chan), "No memory for descriptors\n");
return -ENOMEM;
}
dev_vdbg(dchan2dev(dchan), "%s: allocating\n", axi_chan_name(chan));
pm_runtime_get(chan->chip->dev);
return 0;
}
static void dma_chan_free_chan_resources(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
/* ASSERT: channel is idle */
if (axi_chan_is_hw_enable(chan))
dev_err(dchan2dev(dchan), "%s is non-idle!\n",
axi_chan_name(chan));
axi_chan_disable(chan);
axi_chan_irq_disable(chan, DWAXIDMAC_IRQ_ALL);
vchan_free_chan_resources(&chan->vc);
dma_pool_destroy(chan->desc_pool);
chan->desc_pool = NULL;
dev_vdbg(dchan2dev(dchan),
"%s: free resources, descriptor still allocated: %u\n",
axi_chan_name(chan), atomic_read(&chan->descs_allocated));
pm_runtime_put(chan->chip->dev);
}
static void dw_axi_dma_set_hw_channel(struct axi_dma_chip *chip,
u32 handshake_num, bool set)
{
unsigned long start = 0;
unsigned long reg_value;
unsigned long reg_mask;
unsigned long reg_set;
unsigned long mask;
unsigned long val;
if (!chip->apb_regs) {
dev_dbg(chip->dev, "apb_regs not initialized\n");
return;
}
/*
* An unused DMA channel has a default value of 0x3F.
* Lock the DMA channel by assign a handshake number to the channel.
* Unlock the DMA channel by assign 0x3F to the channel.
*/
if (set) {
reg_set = UNUSED_CHANNEL;
val = handshake_num;
} else {
reg_set = handshake_num;
val = UNUSED_CHANNEL;
}
reg_value = lo_hi_readq(chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
for_each_set_clump8(start, reg_mask, &reg_value, 64) {
if (reg_mask == reg_set) {
mask = GENMASK_ULL(start + 7, start);
reg_value &= ~mask;
reg_value |= rol64(val, start);
lo_hi_writeq(reg_value,
chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
break;
}
}
}
/*
* If DW_axi_dmac sees CHx_CTL.ShadowReg_Or_LLI_Last bit of the fetched LLI
* as 1, it understands that the current block is the final block in the
* transfer and completes the DMA transfer operation at the end of current
* block transfer.
*/
static void set_desc_last(struct axi_dma_hw_desc *desc)
{
u32 val;
val = le32_to_cpu(desc->lli->ctl_hi);
val |= CH_CTL_H_LLI_LAST;
desc->lli->ctl_hi = cpu_to_le32(val);
}
static void write_desc_sar(struct axi_dma_hw_desc *desc, dma_addr_t adr)
{
desc->lli->sar = cpu_to_le64(adr);
}
static void write_desc_dar(struct axi_dma_hw_desc *desc, dma_addr_t adr)
{
desc->lli->dar = cpu_to_le64(adr);
}
static void set_desc_src_master(struct axi_dma_hw_desc *desc)
{
u32 val;
/* Select AXI0 for source master */
val = le32_to_cpu(desc->lli->ctl_lo);
val &= ~CH_CTL_L_SRC_MAST;
desc->lli->ctl_lo = cpu_to_le32(val);
}
static void set_desc_dest_master(struct axi_dma_hw_desc *hw_desc,
struct axi_dma_desc *desc)
{
u32 val;
/* Select AXI1 for source master if available */
val = le32_to_cpu(hw_desc->lli->ctl_lo);
if (desc->chan->chip->dw->hdata->nr_masters > 1)
val |= CH_CTL_L_DST_MAST;
else
val &= ~CH_CTL_L_DST_MAST;
hw_desc->lli->ctl_lo = cpu_to_le32(val);
}
static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
struct axi_dma_hw_desc *hw_desc,
dma_addr_t mem_addr, size_t len)
{
unsigned int data_width = BIT(chan->chip->dw->hdata->m_data_width);
unsigned int reg_width;
unsigned int mem_width;
dma_addr_t device_addr;
size_t axi_block_ts;
size_t block_ts;
u32 ctllo, ctlhi;
u32 burst_len;
axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
mem_width = __ffs(data_width | mem_addr | len);
if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
mem_width = DWAXIDMAC_TRANS_WIDTH_32;
if (!IS_ALIGNED(mem_addr, 4)) {
dev_err(chan->chip->dev, "invalid buffer alignment\n");
return -EINVAL;
}
switch (chan->direction) {
case DMA_MEM_TO_DEV:
reg_width = __ffs(chan->config.dst_addr_width);
device_addr = chan->config.dst_addr;
ctllo = reg_width << CH_CTL_L_DST_WIDTH_POS |
mem_width << CH_CTL_L_SRC_WIDTH_POS |
DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_DST_INC_POS |
DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_SRC_INC_POS;
block_ts = len >> mem_width;
break;
case DMA_DEV_TO_MEM:
reg_width = __ffs(chan->config.src_addr_width);
device_addr = chan->config.src_addr;
ctllo = reg_width << CH_CTL_L_SRC_WIDTH_POS |
mem_width << CH_CTL_L_DST_WIDTH_POS |
DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_DST_INC_POS |
DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_SRC_INC_POS;
block_ts = len >> reg_width;
break;
default:
return -EINVAL;
}
if (block_ts > axi_block_ts)
return -EINVAL;
hw_desc->lli = axi_desc_get(chan, &hw_desc->llp);
if (unlikely(!hw_desc->lli))
return -ENOMEM;
ctlhi = CH_CTL_H_LLI_VALID;
if (chan->chip->dw->hdata->restrict_axi_burst_len) {
burst_len = chan->chip->dw->hdata->axi_rw_burst_len;
ctlhi |= CH_CTL_H_ARLEN_EN | CH_CTL_H_AWLEN_EN |
burst_len << CH_CTL_H_ARLEN_POS |
burst_len << CH_CTL_H_AWLEN_POS;
}
hw_desc->lli->ctl_hi = cpu_to_le32(ctlhi);
if (chan->direction == DMA_MEM_TO_DEV) {
write_desc_sar(hw_desc, mem_addr);
write_desc_dar(hw_desc, device_addr);
} else {
write_desc_sar(hw_desc, device_addr);
write_desc_dar(hw_desc, mem_addr);
}
hw_desc->lli->block_ts_lo = cpu_to_le32(block_ts - 1);
ctllo |= DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_DST_MSIZE_POS |
DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_SRC_MSIZE_POS;
hw_desc->lli->ctl_lo = cpu_to_le32(ctllo);
set_desc_src_master(hw_desc);
hw_desc->len = len;
return 0;
}
static size_t calculate_block_len(struct axi_dma_chan *chan,
dma_addr_t dma_addr, size_t buf_len,
enum dma_transfer_direction direction)
{
u32 data_width, reg_width, mem_width;
size_t axi_block_ts, block_len;
axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
switch (direction) {
case DMA_MEM_TO_DEV:
data_width = BIT(chan->chip->dw->hdata->m_data_width);
mem_width = __ffs(data_width | dma_addr | buf_len);
if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
mem_width = DWAXIDMAC_TRANS_WIDTH_32;
block_len = axi_block_ts << mem_width;
break;
case DMA_DEV_TO_MEM:
reg_width = __ffs(chan->config.src_addr_width);
block_len = axi_block_ts << reg_width;
break;
default:
block_len = 0;
}
return block_len;
}
static struct dma_async_tx_descriptor *
dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
size_t buf_len, size_t period_len,
enum dma_transfer_direction direction,
unsigned long flags)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
struct axi_dma_hw_desc *hw_desc = NULL;
struct axi_dma_desc *desc = NULL;
dma_addr_t src_addr = dma_addr;
u32 num_periods, num_segments;
size_t axi_block_len;
u32 total_segments;
u32 segment_len;
unsigned int i;
int status;
u64 llp = 0;
u8 lms = 0; /* Select AXI0 master for LLI fetching */
num_periods = buf_len / period_len;
axi_block_len = calculate_block_len(chan, dma_addr, buf_len, direction);
if (axi_block_len == 0)
return NULL;
num_segments = DIV_ROUND_UP(period_len, axi_block_len);
segment_len = DIV_ROUND_UP(period_len, num_segments);
total_segments = num_periods * num_segments;
desc = axi_desc_alloc(total_segments);
if (unlikely(!desc))
goto err_desc_get;
chan->direction = direction;
desc->chan = chan;
chan->cyclic = true;
desc->length = 0;
desc->period_len = period_len;
for (i = 0; i < total_segments; i++) {
hw_desc = &desc->hw_desc[i];
status = dw_axi_dma_set_hw_desc(chan, hw_desc, src_addr,
segment_len);
if (status < 0)
goto err_desc_get;
desc->length += hw_desc->len;
/* Set end-of-link to the linked descriptor, so that cyclic
* callback function can be triggered during interrupt.
*/
set_desc_last(hw_desc);
src_addr += segment_len;
}
llp = desc->hw_desc[0].llp;
/* Managed transfer list */
do {
hw_desc = &desc->hw_desc[--total_segments];
write_desc_llp(hw_desc, llp | lms);
llp = hw_desc->llp;
} while (total_segments);
dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true);
return vchan_tx_prep(&chan->vc, &desc->vd, flags);
err_desc_get:
if (desc)
axi_desc_put(desc);
return NULL;
}
static struct dma_async_tx_descriptor *
dw_axi_dma_chan_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 axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
struct axi_dma_hw_desc *hw_desc = NULL;
struct axi_dma_desc *desc = NULL;
u32 num_segments, segment_len;
unsigned int loop = 0;
struct scatterlist *sg;
size_t axi_block_len;
u32 len, num_sgs = 0;
unsigned int i;
dma_addr_t mem;
int status;
u64 llp = 0;
u8 lms = 0; /* Select AXI0 master for LLI fetching */
if (unlikely(!is_slave_direction(direction) || !sg_len))
return NULL;
mem = sg_dma_address(sgl);
len = sg_dma_len(sgl);
axi_block_len = calculate_block_len(chan, mem, len, direction);
if (axi_block_len == 0)
return NULL;
for_each_sg(sgl, sg, sg_len, i)
num_sgs += DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
desc = axi_desc_alloc(num_sgs);
if (unlikely(!desc))
goto err_desc_get;
desc->chan = chan;
desc->length = 0;
chan->direction = direction;
for_each_sg(sgl, sg, sg_len, i) {
mem = sg_dma_address(sg);
len = sg_dma_len(sg);
num_segments = DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
segment_len = DIV_ROUND_UP(sg_dma_len(sg), num_segments);
do {
hw_desc = &desc->hw_desc[loop++];
status = dw_axi_dma_set_hw_desc(chan, hw_desc, mem, segment_len);
if (status < 0)
goto err_desc_get;
desc->length += hw_desc->len;
len -= segment_len;
mem += segment_len;
} while (len >= segment_len);
}
/* Set end-of-link to the last link descriptor of list */
set_desc_last(&desc->hw_desc[num_sgs - 1]);
/* Managed transfer list */
do {
hw_desc = &desc->hw_desc[--num_sgs];
write_desc_llp(hw_desc, llp | lms);
llp = hw_desc->llp;
} while (num_sgs);
dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true);
return vchan_tx_prep(&chan->vc, &desc->vd, flags);
err_desc_get:
if (desc)
axi_desc_put(desc);
return NULL;
}
static struct dma_async_tx_descriptor *
dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr,
dma_addr_t src_adr, size_t len, unsigned long flags)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
size_t block_ts, max_block_ts, xfer_len;
struct axi_dma_hw_desc *hw_desc = NULL;
struct axi_dma_desc *desc = NULL;
u32 xfer_width, reg, num;
u64 llp = 0;
u8 lms = 0; /* Select AXI0 master for LLI fetching */
dev_dbg(chan2dev(chan), "%s: memcpy: src: %pad dst: %pad length: %zd flags: %#lx",
axi_chan_name(chan), &src_adr, &dst_adr, len, flags);
max_block_ts = chan->chip->dw->hdata->block_size[chan->id];
xfer_width = axi_chan_get_xfer_width(chan, src_adr, dst_adr, len);
num = DIV_ROUND_UP(len, max_block_ts << xfer_width);
desc = axi_desc_alloc(num);
if (unlikely(!desc))
goto err_desc_get;
desc->chan = chan;
num = 0;
desc->length = 0;
while (len) {
xfer_len = len;
hw_desc = &desc->hw_desc[num];
/*
* Take care for the alignment.
* Actually source and destination widths can be different, but
* make them same to be simpler.
*/
xfer_width = axi_chan_get_xfer_width(chan, src_adr, dst_adr, xfer_len);
/*
* block_ts indicates the total number of data of width
* to be transferred in a DMA block transfer.
* BLOCK_TS register should be set to block_ts - 1
*/
block_ts = xfer_len >> xfer_width;
if (block_ts > max_block_ts) {
block_ts = max_block_ts;
xfer_len = max_block_ts << xfer_width;
}
hw_desc->lli = axi_desc_get(chan, &hw_desc->llp);
if (unlikely(!hw_desc->lli))
goto err_desc_get;
write_desc_sar(hw_desc, src_adr);
write_desc_dar(hw_desc, dst_adr);
hw_desc->lli->block_ts_lo = cpu_to_le32(block_ts - 1);
reg = CH_CTL_H_LLI_VALID;
if (chan->chip->dw->hdata->restrict_axi_burst_len) {
u32 burst_len = chan->chip->dw->hdata->axi_rw_burst_len;
reg |= (CH_CTL_H_ARLEN_EN |
burst_len << CH_CTL_H_ARLEN_POS |
CH_CTL_H_AWLEN_EN |
burst_len << CH_CTL_H_AWLEN_POS);
}
hw_desc->lli->ctl_hi = cpu_to_le32(reg);
reg = (DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_DST_MSIZE_POS |
DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_SRC_MSIZE_POS |
xfer_width << CH_CTL_L_DST_WIDTH_POS |
xfer_width << CH_CTL_L_SRC_WIDTH_POS |
DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_DST_INC_POS |
DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_SRC_INC_POS);
hw_desc->lli->ctl_lo = cpu_to_le32(reg);
set_desc_src_master(hw_desc);
set_desc_dest_master(hw_desc, desc);
hw_desc->len = xfer_len;
desc->length += hw_desc->len;
/* update the length and addresses for the next loop cycle */
len -= xfer_len;
dst_adr += xfer_len;
src_adr += xfer_len;
num++;
}
/* Set end-of-link to the last link descriptor of list */
set_desc_last(&desc->hw_desc[num - 1]);
/* Managed transfer list */
do {
hw_desc = &desc->hw_desc[--num];
write_desc_llp(hw_desc, llp | lms);
llp = hw_desc->llp;
} while (num);
return vchan_tx_prep(&chan->vc, &desc->vd, flags);
err_desc_get:
if (desc)
axi_desc_put(desc);
return NULL;
}
static int dw_axi_dma_chan_slave_config(struct dma_chan *dchan,
struct dma_slave_config *config)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
memcpy(&chan->config, config, sizeof(*config));
return 0;
}
static void axi_chan_dump_lli(struct axi_dma_chan *chan,
struct axi_dma_hw_desc *desc)
{
dev_err(dchan2dev(&chan->vc.chan),
"SAR: 0x%llx DAR: 0x%llx LLP: 0x%llx BTS 0x%x CTL: 0x%x:%08x",
le64_to_cpu(desc->lli->sar),
le64_to_cpu(desc->lli->dar),
le64_to_cpu(desc->lli->llp),
le32_to_cpu(desc->lli->block_ts_lo),
le32_to_cpu(desc->lli->ctl_hi),
le32_to_cpu(desc->lli->ctl_lo));
}
static void axi_chan_list_dump_lli(struct axi_dma_chan *chan,
struct axi_dma_desc *desc_head)
{
int count = atomic_read(&chan->descs_allocated);
int i;
for (i = 0; i < count; i++)
axi_chan_dump_lli(chan, &desc_head->hw_desc[i]);
}
static noinline void axi_chan_handle_err(struct axi_dma_chan *chan, u32 status)
{
struct virt_dma_desc *vd;
unsigned long flags;
spin_lock_irqsave(&chan->vc.lock, flags);
axi_chan_disable(chan);
/* The bad descriptor currently is in the head of vc list */
vd = vchan_next_desc(&chan->vc);
/* Remove the completed descriptor from issued list */
list_del(&vd->node);
/* WARN about bad descriptor */
dev_err(chan2dev(chan),
"Bad descriptor submitted for %s, cookie: %d, irq: 0x%08x\n",
axi_chan_name(chan), vd->tx.cookie, status);
axi_chan_list_dump_lli(chan, vd_to_axi_desc(vd));
vchan_cookie_complete(vd);
/* Try to restart the controller */
axi_chan_start_first_queued(chan);
spin_unlock_irqrestore(&chan->vc.lock, flags);
}
static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
{
int count = atomic_read(&chan->descs_allocated);
struct axi_dma_hw_desc *hw_desc;
struct axi_dma_desc *desc;
struct virt_dma_desc *vd;
unsigned long flags;
u64 llp;
int i;
spin_lock_irqsave(&chan->vc.lock, flags);
if (unlikely(axi_chan_is_hw_enable(chan))) {
dev_err(chan2dev(chan), "BUG: %s caught DWAXIDMAC_IRQ_DMA_TRF, but channel not idle!\n",
axi_chan_name(chan));
axi_chan_disable(chan);
}
/* The completed descriptor currently is in the head of vc list */
vd = vchan_next_desc(&chan->vc);
if (chan->cyclic) {
desc = vd_to_axi_desc(vd);
if (desc) {
llp = lo_hi_readq(chan->chan_regs + CH_LLP);
for (i = 0; i < count; i++) {
hw_desc = &desc->hw_desc[i];
if (hw_desc->llp == llp) {
axi_chan_irq_clear(chan, hw_desc->lli->status_lo);
hw_desc->lli->ctl_hi |= CH_CTL_H_LLI_VALID;
desc->completed_blocks = i;
if (((hw_desc->len * (i + 1)) % desc->period_len) == 0)
vchan_cyclic_callback(vd);
break;
}
}
axi_chan_enable(chan);
}
} else {
/* Remove the completed descriptor from issued list before completing */
list_del(&vd->node);
vchan_cookie_complete(vd);
/* Submit queued descriptors after processing the completed ones */
axi_chan_start_first_queued(chan);
}
spin_unlock_irqrestore(&chan->vc.lock, flags);
}
static irqreturn_t dw_axi_dma_interrupt(int irq, void *dev_id)
{
struct axi_dma_chip *chip = dev_id;
struct dw_axi_dma *dw = chip->dw;
struct axi_dma_chan *chan;
u32 status, i;
/* Disable DMAC inerrupts. We'll enable them after processing chanels */
axi_dma_irq_disable(chip);
/* Poll, clear and process every chanel interrupt status */
for (i = 0; i < dw->hdata->nr_channels; i++) {
chan = &dw->chan[i];
status = axi_chan_irq_read(chan);
axi_chan_irq_clear(chan, status);
dev_vdbg(chip->dev, "%s %u IRQ status: 0x%08x\n",
axi_chan_name(chan), i, status);
if (status & DWAXIDMAC_IRQ_ALL_ERR)
axi_chan_handle_err(chan, status);
else if (status & DWAXIDMAC_IRQ_DMA_TRF)
axi_chan_block_xfer_complete(chan);
}
/* Re-enable interrupts */
axi_dma_irq_enable(chip);
return IRQ_HANDLED;
}
static int dma_chan_terminate_all(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
u32 chan_active = BIT(chan->id) << DMAC_CHAN_EN_SHIFT;
unsigned long flags;
u32 val;
int ret;
LIST_HEAD(head);
axi_chan_disable(chan);
ret = readl_poll_timeout_atomic(chan->chip->regs + DMAC_CHEN, val,
!(val & chan_active), 1000, 10000);
if (ret == -ETIMEDOUT)
dev_warn(dchan2dev(dchan),
"%s failed to stop\n", axi_chan_name(chan));
if (chan->direction != DMA_MEM_TO_MEM)
dw_axi_dma_set_hw_channel(chan->chip,
chan->hw_handshake_num, false);
if (chan->direction == DMA_MEM_TO_DEV)
dw_axi_dma_set_byte_halfword(chan, false);
spin_lock_irqsave(&chan->vc.lock, flags);
vchan_get_all_descriptors(&chan->vc, &head);
chan->cyclic = false;
spin_unlock_irqrestore(&chan->vc.lock, flags);
vchan_dma_desc_free_list(&chan->vc, &head);
dev_vdbg(dchan2dev(dchan), "terminated: %s\n", axi_chan_name(chan));
return 0;
}
static int dma_chan_pause(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
unsigned long flags;
unsigned int timeout = 20; /* timeout iterations */
u32 val;
spin_lock_irqsave(&chan->vc.lock, flags);
val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
val |= BIT(chan->id) << DMAC_CHAN_SUSP_SHIFT |
BIT(chan->id) << DMAC_CHAN_SUSP_WE_SHIFT;
axi_dma_iowrite32(chan->chip, DMAC_CHEN, val);
do {
if (axi_chan_irq_read(chan) & DWAXIDMAC_IRQ_SUSPENDED)
break;
udelay(2);
} while (--timeout);
axi_chan_irq_clear(chan, DWAXIDMAC_IRQ_SUSPENDED);
chan->is_paused = true;
spin_unlock_irqrestore(&chan->vc.lock, flags);
return timeout ? 0 : -EAGAIN;
}
/* Called in chan locked context */
static inline void axi_chan_resume(struct axi_dma_chan *chan)
{
u32 val;
val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
val &= ~(BIT(chan->id) << DMAC_CHAN_SUSP_SHIFT);
val |= (BIT(chan->id) << DMAC_CHAN_SUSP_WE_SHIFT);
axi_dma_iowrite32(chan->chip, DMAC_CHEN, val);
chan->is_paused = false;
}
static int dma_chan_resume(struct dma_chan *dchan)
{
struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
unsigned long flags;
spin_lock_irqsave(&chan->vc.lock, flags);
if (chan->is_paused)
axi_chan_resume(chan);
spin_unlock_irqrestore(&chan->vc.lock, flags);
return 0;
}
static int axi_dma_suspend(struct axi_dma_chip *chip)
{
axi_dma_irq_disable(chip);
axi_dma_disable(chip);
clk_disable_unprepare(chip->core_clk);
clk_disable_unprepare(chip->cfgr_clk);
return 0;
}
static int axi_dma_resume(struct axi_dma_chip *chip)
{
int ret;
ret = clk_prepare_enable(chip->cfgr_clk);
if (ret < 0)
return ret;
ret = clk_prepare_enable(chip->core_clk);
if (ret < 0)
return ret;
axi_dma_enable(chip);
axi_dma_irq_enable(chip);
return 0;
}
static int __maybe_unused axi_dma_runtime_suspend(struct device *dev)
{
struct axi_dma_chip *chip = dev_get_drvdata(dev);
return axi_dma_suspend(chip);
}
static int __maybe_unused axi_dma_runtime_resume(struct device *dev)
{
struct axi_dma_chip *chip = dev_get_drvdata(dev);
return axi_dma_resume(chip);
}
static struct dma_chan *dw_axi_dma_of_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct dw_axi_dma *dw = ofdma->of_dma_data;
struct axi_dma_chan *chan;
struct dma_chan *dchan;
dchan = dma_get_any_slave_channel(&dw->dma);
if (!dchan)
return NULL;
chan = dchan_to_axi_dma_chan(dchan);
chan->hw_handshake_num = dma_spec->args[0];
return dchan;
}
static int parse_device_properties(struct axi_dma_chip *chip)
{
struct device *dev = chip->dev;
u32 tmp, carr[DMAC_MAX_CHANNELS];
int ret;
ret = device_property_read_u32(dev, "dma-channels", &tmp);
if (ret)
return ret;
if (tmp == 0 || tmp > DMAC_MAX_CHANNELS)
return -EINVAL;
chip->dw->hdata->nr_channels = tmp;
ret = device_property_read_u32(dev, "snps,dma-masters", &tmp);
if (ret)
return ret;
if (tmp == 0 || tmp > DMAC_MAX_MASTERS)
return -EINVAL;
chip->dw->hdata->nr_masters = tmp;
ret = device_property_read_u32(dev, "snps,data-width", &tmp);
if (ret)
return ret;
if (tmp > DWAXIDMAC_TRANS_WIDTH_MAX)
return -EINVAL;
chip->dw->hdata->m_data_width = tmp;
ret = device_property_read_u32_array(dev, "snps,block-size", carr,
chip->dw->hdata->nr_channels);
if (ret)
return ret;
for (tmp = 0; tmp < chip->dw->hdata->nr_channels; tmp++) {
if (carr[tmp] == 0 || carr[tmp] > DMAC_MAX_BLK_SIZE)
return -EINVAL;
chip->dw->hdata->block_size[tmp] = carr[tmp];
}
ret = device_property_read_u32_array(dev, "snps,priority", carr,
chip->dw->hdata->nr_channels);
if (ret)
return ret;
/* Priority value must be programmed within [0:nr_channels-1] range */
for (tmp = 0; tmp < chip->dw->hdata->nr_channels; tmp++) {
if (carr[tmp] >= chip->dw->hdata->nr_channels)
return -EINVAL;
chip->dw->hdata->priority[tmp] = carr[tmp];
}
/* axi-max-burst-len is optional property */
ret = device_property_read_u32(dev, "snps,axi-max-burst-len", &tmp);
if (!ret) {
if (tmp > DWAXIDMAC_ARWLEN_MAX + 1)
return -EINVAL;
if (tmp < DWAXIDMAC_ARWLEN_MIN + 1)
return -EINVAL;
chip->dw->hdata->restrict_axi_burst_len = true;
chip->dw->hdata->axi_rw_burst_len = tmp - 1;
}
return 0;
}
static int dw_probe(struct platform_device *pdev)
{
struct device_node *node = pdev->dev.of_node;
struct axi_dma_chip *chip;
struct resource *mem;
struct dw_axi_dma *dw;
struct dw_axi_dma_hcfg *hdata;
u32 i;
int ret;
chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
if (!dw)
return -ENOMEM;
hdata = devm_kzalloc(&pdev->dev, sizeof(*hdata), GFP_KERNEL);
if (!hdata)
return -ENOMEM;
chip->dw = dw;
chip->dev = &pdev->dev;
chip->dw->hdata = hdata;
chip->irq = platform_get_irq(pdev, 0);
if (chip->irq < 0)
return chip->irq;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
chip->regs = devm_ioremap_resource(chip->dev, mem);
if (IS_ERR(chip->regs))
return PTR_ERR(chip->regs);
if (of_device_is_compatible(node, "intel,kmb-axi-dma")) {
chip->apb_regs = devm_platform_ioremap_resource(pdev, 1);
if (IS_ERR(chip->apb_regs))
return PTR_ERR(chip->apb_regs);
}
chip->core_clk = devm_clk_get(chip->dev, "core-clk");
if (IS_ERR(chip->core_clk))
return PTR_ERR(chip->core_clk);
chip->cfgr_clk = devm_clk_get(chip->dev, "cfgr-clk");
if (IS_ERR(chip->cfgr_clk))
return PTR_ERR(chip->cfgr_clk);
ret = parse_device_properties(chip);
if (ret)
return ret;
dw->chan = devm_kcalloc(chip->dev, hdata->nr_channels,
sizeof(*dw->chan), GFP_KERNEL);
if (!dw->chan)
return -ENOMEM;
ret = devm_request_irq(chip->dev, chip->irq, dw_axi_dma_interrupt,
IRQF_SHARED, KBUILD_MODNAME, chip);
if (ret)
return ret;
INIT_LIST_HEAD(&dw->dma.channels);
for (i = 0; i < hdata->nr_channels; i++) {
struct axi_dma_chan *chan = &dw->chan[i];
chan->chip = chip;
chan->id = i;
chan->chan_regs = chip->regs + COMMON_REG_LEN + i * CHAN_REG_LEN;
atomic_set(&chan->descs_allocated, 0);
chan->vc.desc_free = vchan_desc_put;
vchan_init(&chan->vc, &dw->dma);
}
/* Set capabilities */
dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
dma_cap_set(DMA_CYCLIC, dw->dma.cap_mask);
/* DMA capabilities */
dw->dma.chancnt = hdata->nr_channels;
dw->dma.src_addr_widths = AXI_DMA_BUSWIDTHS;
dw->dma.dst_addr_widths = AXI_DMA_BUSWIDTHS;
dw->dma.directions = BIT(DMA_MEM_TO_MEM);
dw->dma.directions |= BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
dw->dma.dev = chip->dev;
dw->dma.device_tx_status = dma_chan_tx_status;
dw->dma.device_issue_pending = dma_chan_issue_pending;
dw->dma.device_terminate_all = dma_chan_terminate_all;
dw->dma.device_pause = dma_chan_pause;
dw->dma.device_resume = dma_chan_resume;
dw->dma.device_alloc_chan_resources = dma_chan_alloc_chan_resources;
dw->dma.device_free_chan_resources = dma_chan_free_chan_resources;
dw->dma.device_prep_dma_memcpy = dma_chan_prep_dma_memcpy;
dw->dma.device_synchronize = dw_axi_dma_synchronize;
dw->dma.device_config = dw_axi_dma_chan_slave_config;
dw->dma.device_prep_slave_sg = dw_axi_dma_chan_prep_slave_sg;
dw->dma.device_prep_dma_cyclic = dw_axi_dma_chan_prep_cyclic;
/*
* Synopsis DesignWare AxiDMA datasheet mentioned Maximum
* supported blocks is 1024. Device register width is 4 bytes.
* Therefore, set constraint to 1024 * 4.
*/
dw->dma.dev->dma_parms = &dw->dma_parms;
dma_set_max_seg_size(&pdev->dev, MAX_BLOCK_SIZE);
platform_set_drvdata(pdev, chip);
pm_runtime_enable(chip->dev);
/*
* We can't just call pm_runtime_get here instead of
* pm_runtime_get_noresume + axi_dma_resume because we need
* driver to work also without Runtime PM.
*/
pm_runtime_get_noresume(chip->dev);
ret = axi_dma_resume(chip);
if (ret < 0)
goto err_pm_disable;
axi_dma_hw_init(chip);
pm_runtime_put(chip->dev);
ret = dmaenginem_async_device_register(&dw->dma);
if (ret)
goto err_pm_disable;
/* Register with OF helpers for DMA lookups */
ret = of_dma_controller_register(pdev->dev.of_node,
dw_axi_dma_of_xlate, dw);
if (ret < 0)
dev_warn(&pdev->dev,
"Failed to register OF DMA controller, fallback to MEM_TO_MEM mode\n");
dev_info(chip->dev, "DesignWare AXI DMA Controller, %d channels\n",
dw->hdata->nr_channels);
return 0;
err_pm_disable:
pm_runtime_disable(chip->dev);
return ret;
}
static int dw_remove(struct platform_device *pdev)
{
struct axi_dma_chip *chip = platform_get_drvdata(pdev);
struct dw_axi_dma *dw = chip->dw;
struct axi_dma_chan *chan, *_chan;
u32 i;
/* Enable clk before accessing to registers */
clk_prepare_enable(chip->cfgr_clk);
clk_prepare_enable(chip->core_clk);
axi_dma_irq_disable(chip);
for (i = 0; i < dw->hdata->nr_channels; i++) {
axi_chan_disable(&chip->dw->chan[i]);
axi_chan_irq_disable(&chip->dw->chan[i], DWAXIDMAC_IRQ_ALL);
}
axi_dma_disable(chip);
pm_runtime_disable(chip->dev);
axi_dma_suspend(chip);
devm_free_irq(chip->dev, chip->irq, chip);
of_dma_controller_free(chip->dev->of_node);
list_for_each_entry_safe(chan, _chan, &dw->dma.channels,
vc.chan.device_node) {
list_del(&chan->vc.chan.device_node);
tasklet_kill(&chan->vc.task);
}
return 0;
}
static const struct dev_pm_ops dw_axi_dma_pm_ops = {
SET_RUNTIME_PM_OPS(axi_dma_runtime_suspend, axi_dma_runtime_resume, NULL)
};
static const struct of_device_id dw_dma_of_id_table[] = {
{ .compatible = "snps,axi-dma-1.01a" },
{ .compatible = "intel,kmb-axi-dma" },
{}
};
MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
static struct platform_driver dw_driver = {
.probe = dw_probe,
.remove = dw_remove,
.driver = {
.name = KBUILD_MODNAME,
.of_match_table = dw_dma_of_id_table,
.pm = &dw_axi_dma_pm_ops,
},
};
module_platform_driver(dw_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Synopsys DesignWare AXI DMA Controller platform driver");
MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");