Re: [PATCH 3/3] dmaengine: dw-edma: Add support for native HDMA

From: Serge Semin
Date: Fri Feb 10 2023 - 13:14:07 EST


On Wed, Sep 21, 2022 at 02:48:52PM +0800, Cai Huoqing wrote:
> From: caihuoqing <caihuoqing@xxxxxxxxx>
>
> Add support for HDMA NATIVE, as long the IP design has set
> the compatible register map parameter-HDMA_NATIVE,
> which allows compatibility for native HDMA register configuration.
>
> The HDMA Hyper-DMA IP is an enhancement of the eDMA embedded-DMA IP.
> And the native HDMA registers are different from eDMA,
> so this patch add support for HDMA NATIVE mode.
>
> HDMA write and read channels operate independently to maximize
> the performance of the HDMA read and write data transfer over
> the link When you configure the HDMA with multiple read channels,
> then it uses a round robin (RR) arbitration scheme to select
> the next read channel to be serviced.
> The same applies when you have multiple write channels.
>
> The native HDMA driver also supports a maximum of 16 independent
> channels (8 write + 8 read), which can run simultaneously.
> Both SAR (Source Address Register) and DAR (Destination Address Register)
> are alignmented to byte.
>
> Signed-off-by: caihuoqing <caihuoqing@xxxxxxxxx>
> ---
> drivers/dma/dw-edma/Makefile | 6 +-
> drivers/dma/dw-edma/dw-edma-core.c | 6 +-
> drivers/dma/dw-edma/dw-hdma-v0-core.c | 308 +++++++++++++++++++++++
> drivers/dma/dw-edma/dw-hdma-v0-core.h | 17 ++
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.c | 150 +++++++++++
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.h | 22 ++
> drivers/dma/dw-edma/dw-hdma-v0-regs.h | 98 ++++++++
> include/linux/dma/edma.h | 3 +-
> 8 files changed, 606 insertions(+), 4 deletions(-)
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-core.c
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-core.h
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-debugfs.h
> create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-regs.h
>
> diff --git a/drivers/dma/dw-edma/Makefile b/drivers/dma/dw-edma/Makefile
> index 8d45c0d5689d..958e7f202d11 100644
> --- a/drivers/dma/dw-edma/Makefile
> +++ b/drivers/dma/dw-edma/Makefile
> @@ -1,7 +1,9 @@
> # SPDX-License-Identifier: GPL-2.0
>
> obj-$(CONFIG_DW_EDMA) += dw-edma.o
> -dw-edma-$(CONFIG_DEBUG_FS) := dw-edma-v0-debugfs.o
> +dw-edma-$(CONFIG_DEBUG_FS) := dw-edma-v0-debugfs.o \
> + dw-hdma-v0-debugfs.o
> dw-edma-objs := dw-edma-core.o \
> - dw-edma-v0-core.o $(dw-edma-y)
> + dw-edma-v0-core.o \
> + dw-hdma-v0-core.o $(dw-edma-y)
> obj-$(CONFIG_DW_EDMA_PCIE) += dw-edma-pcie.o
> diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c
> index a66e4216a5d3..59c71e5cc8f6 100644
> --- a/drivers/dma/dw-edma/dw-edma-core.c
> +++ b/drivers/dma/dw-edma/dw-edma-core.c
> @@ -19,6 +19,7 @@
>
> #include "dw-edma-core.h"
> #include "dw-edma-v0-core.h"
> +#include "dw-hdma-v0-core.h"
> #include "../dmaengine.h"
> #include "../virt-dma.h"
>
> @@ -952,7 +953,10 @@ int dw_edma_probe(struct dw_edma_chip *chip)
>
> dw->chip = chip;
>
> - dw_edma_v0_core_register(dw);
> + if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
> + dw_hdma_v0_core_register(dw);
> + else
> + dw_edma_v0_core_register(dw);
>
> raw_spin_lock_init(&dw->lock);
>
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-core.c b/drivers/dma/dw-edma/dw-hdma-v0-core.c
> new file mode 100644
> index 000000000000..4ed6881bf3e9
> --- /dev/null
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-core.c
> @@ -0,0 +1,308 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2022 Cai Huoqing
> + * Synopsys DesignWare HDMA v0 core
> + */
> +
> +#include <linux/bitfield.h>
> +
> +#include "dw-edma-core.h"

> +#include "dw-edma-v0-core.h"
> +#include "dw-edma-v0-regs.h"

Do you need these headers here?

> +#include "dw-hdma-v0-core.h"
> +#include "dw-hdma-v0-regs.h"
> +#include "dw-hdma-v0-debugfs.h"
> +
> +enum dw_hdma_control {
> + DW_HDMA_V0_CB = BIT(0),
> + DW_HDMA_V0_TCB = BIT(1),
> + DW_HDMA_V0_LLP = BIT(2),
> + DW_HDMA_V0_LIE = BIT(3),
> + DW_HDMA_V0_RIE = BIT(4),
> + DW_HDMA_V0_CCS = BIT(8),
> + DW_HDMA_V0_LLE = BIT(9),
> +};
> +static inline struct dw_hdma_v0_regs __iomem *__dw_regs(struct dw_edma *dw)
> +{
> + return dw->chip->reg_base;
> +}
> +
> +static inline struct dw_hdma_v0_ch_regs __iomem *
> +__dw_ch_regs(struct dw_edma *dw, enum dw_edma_dir dir, u16 ch)
> +{
> +
> + if (dir == EDMA_DIR_WRITE)
> + return &(__dw_regs(dw)->ch[ch].wr);
> + else
> + return &(__dw_regs(dw)->ch[ch].rd);
> +}
> +
> +#define SET_CH_32(dw, dir, ch, name, value) \
> + writel(value, &(__dw_ch_regs(dw, dir, ch)->name))
> +
> +#define GET_CH_32(dw, dir, ch, name) \
> + readl(&(__dw_ch_regs(dw, dir, ch)->name))
> +
> +#define SET_BOTH_CH_32(dw, ch, name, value) \
> + do { \
> + writel(value, &(__dw_ch_regs(dw, EDMA_DIR_WRITE, ch)->name)); \
> + writel(value, &(__dw_ch_regs(dw, EDMA_DIR_READ, ch)->name)); \
> + } while (0)
> +

> +#define SET_LL_32(ll, value) \
> + writel(value, ll)

This macro is no longer value since the linked-list descriptors are
now located on the CPU memory. Please see the patch
https://lore.kernel.org/linux-pci/20230113171409.30470-24-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
which is already in the @Bjron tree for being merged on the next
m-window.

> +
> +/* HDMA management callbacks */
> +static void dw_hdma_v0_core_off(struct dw_edma *dw)
> +{
> + int id;
> +
> + for (id = 0; id < HDMA_V0_MAX_NR_CH; id++) {
> + SET_BOTH_CH_32(dw, id, int_setup,
> + HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
> + SET_BOTH_CH_32(dw, id, int_clear,

> + HDMA_V0_STOP_INT_MASK & HDMA_V0_ABORT_INT_MASK);
^
Shouldn't '|' be here instead? -----------------------+

> + SET_BOTH_CH_32(dw, id, ch_en, 0);
> + }
> +}
> +
> +static u16 dw_hdma_v0_core_ch_count(struct dw_edma *dw, enum dw_edma_dir dir)
> +{
> + u32 num_ch = 0;
> + int id;
> +
> + for (id = 0; id < HDMA_V0_MAX_NR_CH; id++) {
> + if (GET_CH_32(dw, id, dir, ch_en) & BIT(0))
> + num_ch++;
> + }
> +
> + if (num_ch > HDMA_V0_MAX_NR_CH)
> + num_ch = HDMA_V0_MAX_NR_CH;
> +
> + return (u16)num_ch;
> +}
> +
> +static enum dma_status dw_hdma_v0_core_ch_status(struct dw_edma_chan *chan)
> +{
> + struct dw_edma *dw = chan->dw;
> + u32 tmp;
> +
> + tmp = FIELD_GET(HDMA_V0_CH_STATUS_MASK,
> + GET_CH_32(dw, chan->id, chan->dir, ch_stat));
> +
> + if (tmp == 1)
> + return DMA_IN_PROGRESS;
> + else if (tmp == 3)
> + return DMA_COMPLETE;
> + else
> + return DMA_ERROR;
> +}
> +
> +static void dw_hdma_v0_core_clear_done_int(struct dw_edma_chan *chan)
> +{
> + struct dw_edma *dw = chan->dw;
> +
> + SET_CH_32(dw, chan->dir, chan->id, int_clear, HDMA_V0_STOP_INT_MASK);
> +}
> +
> +static void dw_hdma_v0_core_clear_abort_int(struct dw_edma_chan *chan)
> +{
> + struct dw_edma *dw = chan->dw;
> +
> + SET_CH_32(dw, chan->dir, chan->id, int_clear, HDMA_V0_ABORT_INT_MASK);
> +}
> +
> +static u32 dw_hdma_v0_core_status_int(struct dw_edma_chan *chan)
> +{
> + struct dw_edma *dw = chan->dw;
> +
> + return GET_CH_32(dw, chan->dir, chan->id, int_stat);
> +}
> +
> +static u32 dw_hdma_v0_core_check_done_int(u32 val)
> +{

> + return (FIELD_GET(HDMA_V0_STOP_INT_MASK, val) == BIT(0));
> +}
> +
> +static u32 dw_hdma_v0_core_check_abort_int(u32 val)
> +{
> + return (FIELD_GET(HDMA_V0_ABORT_INT_MASK, val) == BIT(0));

Em, what about
return FIELD_GET(HDMA_V0_*_INT_MASK, val);
?

> +}
> +
> +static
> +void dw_hdma_v0_core_done_handle(struct dw_edma_irq *dw_irq,
> + void (*done_cb)(struct dw_edma_chan *chan),
> + enum dw_edma_dir dir)
> +{
> + struct dw_edma *dw = dw_irq->dw;
> + unsigned long total, pos, val;
> + unsigned long off, mask;
> +
> + if (dir == EDMA_DIR_WRITE) {
> + total = dw->wr_ch_cnt;
> + off = 0;
> + mask = dw_irq->wr_mask;
> + } else {
> + total = dw->rd_ch_cnt;
> + off = dw->wr_ch_cnt;
> + mask = dw_irq->rd_mask;
> + }
> +
> + for_each_set_bit(pos, &mask, total) {
> + struct dw_edma_chan *chan = &dw->chan[pos + off];
> +
> + val = dw_hdma_v0_core_status_int(chan);
> + if (dw_hdma_v0_core_check_done_int(val))
> + done_cb(chan);
> + }
> +}
> +
> +static
> +void dw_hdma_v0_core_abort_handle(struct dw_edma_irq *dw_irq,
> + void (*abort_cb)(struct dw_edma_chan *chan),
> + enum dw_edma_dir dir)
> +{
> + struct dw_edma *dw = dw_irq->dw;
> + unsigned long total, pos, val;
> + unsigned long off, mask;
> +
> + if (dir == EDMA_DIR_WRITE) {
> + total = dw->wr_ch_cnt;
> + off = 0;
> + mask = dw_irq->wr_mask;
> + } else {
> + total = dw->rd_ch_cnt;
> + off = dw->wr_ch_cnt;
> + mask = dw_irq->rd_mask;
> + }
> +
> + for_each_set_bit(pos, &mask, total) {
> + struct dw_edma_chan *chan = &dw->chan[pos + off];
> +
> + val = dw_hdma_v0_core_status_int(chan);
> + if (dw_hdma_v0_core_check_abort_int(val))
> + abort_cb(chan);
> + }
> +}
> +
> +static void dw_hdma_v0_core_write_chunk(struct dw_edma_chunk *chunk)
> +{
> + struct dw_edma_burst *child;
> + struct dw_edma_chan *chan = chunk->chan;
> + struct dw_edma_v0_lli __iomem *lli;
> + struct dw_edma_v0_llp __iomem *llp;
> + u32 control = 0, i = 0;
> + int j;
> +
> + lli = chunk->ll_region.vaddr;
> +
> + if (chunk->cb)
> + control = DW_HDMA_V0_CB;
> +
> + j = chunk->bursts_alloc;
> + list_for_each_entry(child, &chunk->burst->list, list) {
> + j--;
> + if (!j) {
> + control |= DW_HDMA_V0_LIE;
> + if (!(chan->dw->chip->flags & DW_EDMA_CHIP_LOCAL))
> + control |= DW_HDMA_V0_RIE;
> + }

> + /* Channel control */
> + SET_LL_32(&lli[i].control, control);
> + /* Transfer size */
> + SET_LL_32(&lli[i].transfer_size, child->sz);
> + /* SAR */
> + SET_LL_32(&lli[i].sar.lsb, lower_32_bits(child->sar));
> + SET_LL_32(&lli[i].sar.msb, upper_32_bits(child->sar));
> + /* DAR */
> + SET_LL_32(&lli[i].dar.lsb, lower_32_bits(child->dar));
> + SET_LL_32(&lli[i].dar.msb, upper_32_bits(child->dar));
> + i++;
> + }
> +
> + llp = (void __iomem *)&lli[i];
> + control = DW_HDMA_V0_LLP | DW_HDMA_V0_TCB;
> + if (!chunk->cb)
> + control |= DW_HDMA_V0_CB;
> +
> + /* Channel control */
> + SET_LL_32(&llp->control, control);
> + /* Linked list */
> + SET_LL_32(&llp->llp.lsb, lower_32_bits(chunk->ll_region.paddr));
> + SET_LL_32(&llp->llp.msb, upper_32_bits(chunk->ll_region.paddr));

Please see the way the LL access is now implemented for eDMA:
https://lore.kernel.org/linux-pci/20230113171409.30470-24-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
The eDMA v0 core now supports the LL descriptors placed on the CPU memory.
This driver should be properly fixed too.

> +}
> +
> +static void dw_hdma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
> +{
> + struct dw_edma_chan *chan = chunk->chan;
> + struct dw_edma *dw = chan->dw;
> + u32 tmp;
> +
> + dw_hdma_v0_core_write_chunk(chunk);
> +
> + if (first) {
> + /* Enable engine */
> + SET_CH_32(dw, chan->dir, chan->id, ch_en, BIT(0));
> + /* Interrupt enable&unmask - done, abort */
> + tmp = GET_CH_32(dw, chan->dir, chan->id, int_setup);

> + tmp |= HDMA_V0_STOP_INT_MASK;
> + tmp |= HDMA_V0_ABORT_INT_MASK;
> + tmp |= HDMA_V0_LOCAL_ABORT_INT_EN;
> + tmp |= HDMA_V0_LOCAL_STOP_INT_EN;

Using multiple bitwise-OR ops seems a bit more robust then multiple
'|=' ops since the constants will be combined on compile-time.

> + SET_CH_32(dw, chan->dir, chan->id, int_setup, tmp);
> + /* Channel control */
> + SET_CH_32(dw, chan->dir, chan->id, control1, HDMA_V0_LINKLIST_EN);
> + /* Linked list */
> + /* llp is not aligned on 64bit -> keep 32bit accesses */
> + SET_CH_32(dw, chan->dir, chan->id, llp.lsb,
> + lower_32_bits(chunk->ll_region.paddr));
> + SET_CH_32(dw, chan->dir, chan->id, llp.msb,
> + upper_32_bits(chunk->ll_region.paddr));
> + }
> + /* set consumer cycle */
> + SET_CH_32(dw, chan->dir, chan->id, cycle_sync,
> + HDMA_V0_CONSUMER_CYCLE_STAT | HDMA_V0_CONSUMER_CYCLE_BIT);
> + /* Doorbell */
> + SET_CH_32(dw, chan->dir, chan->id, doorbell, HDMA_V0_DOORBELL_START);
> +}
> +
> +static int dw_hdma_v0_core_ch_config(struct dw_edma_chan *chan)
> +{
> + struct dw_edma *dw = chan->dw;
> +
> + /* MSI done addr - low, high */
> + SET_CH_32(dw, chan->dir, chan->id, msi_stop.lsb, chan->msi.address_lo);
> + SET_CH_32(dw, chan->dir, chan->id, msi_stop.msb, chan->msi.address_hi);
> + /* MSI abort addr - low, high */
> + SET_CH_32(dw, chan->dir, chan->id, msi_abort.lsb, chan->msi.address_lo);

> + SET_CH_32(dw, chan->dir, chan->id, msi_abort.msb, chan->msi.address_hi);
> + SET_CH_32(dw, chan->dir, chan->id, msi_abort.msb, chan->msi.address_hi);

Two identical lines. Typo?

> + /* config MSI data */
> + SET_CH_32(dw, chan->dir, chan->id, msi_msgdata, chan->msi.data);
> +
> + return 0;
> +}
> +
> +/* eDMA debugfs callbacks */
> +static void dw_hdma_v0_core_debugfs_on(struct dw_edma *dw)
> +{
> + dw_hdma_v0_debugfs_on(dw);
> +}
> +
> +static const struct dw_edma_core_ops hdma_core = {
> + .dw_xdma_core_off = dw_hdma_v0_core_off,
> + .dw_xdma_core_ch_count = dw_hdma_v0_core_ch_count,
> + .dw_xdma_core_ch_status = dw_hdma_v0_core_ch_status,
> + .dw_xdma_core_clear_done_int = dw_hdma_v0_core_clear_done_int,
> + .dw_xdma_core_clear_abort_int = dw_hdma_v0_core_clear_abort_int,
> + .dw_xdma_core_done_handle = dw_hdma_v0_core_done_handle,
> + .dw_xdma_core_abort_handle = dw_hdma_v0_core_abort_handle,
> + .dw_xdma_core_start = dw_hdma_v0_core_start,
> + .dw_xdma_core_ch_config = dw_hdma_v0_core_ch_config,
> + .dw_xdma_core_debugfs_on = dw_hdma_v0_core_debugfs_on,
> +};
> +
> +void dw_hdma_v0_core_register(struct dw_edma *dw)
> +{
> + dw->core = &hdma_core;
> +}
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-core.h b/drivers/dma/dw-edma/dw-hdma-v0-core.h
> new file mode 100644
> index 000000000000..dc9b93e469ae
> --- /dev/null
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-core.h
> @@ -0,0 +1,17 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2022 Cai Huoqing
> + * Synopsys DesignWare HDMA v0 core
> + *
> + * Author: Cai Huoqing <cai.huoqing@xxxxxxxxx>
> + */
> +
> +#ifndef _DW_HDMA_V0_CORE_H
> +#define _DW_HDMA_V0_CORE_H
> +
> +#include <linux/dma/edma.h>
> +
> +/* HDMA core operation register*/
> +void dw_hdma_v0_core_register(struct dw_edma *dw);
> +
> +#endif /* _DW_HDMA_V0_CORE_H */
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
> new file mode 100644
> index 000000000000..1f973b21eef9

> --- /dev/null
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c

Please see the way the module now looks in the @Bjorn tree and
refactor your DebugFS part being similar. Currently due to the way
your driver is designed it's impossible to register more than one HDMA
device in the system.

> @@ -0,0 +1,150 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2022 Cai Huoqing
> + * Synopsys DesignWare HDMA v0 debugfs
> + *
> + * Author: Cai Huoqing <cai.huoqing@xxxxxxxxx>
> + */
> +
> +#include <linux/debugfs.h>
> +#include <linux/bitfield.h>
> +
> +#include "dw-hdma-v0-debugfs.h"
> +#include "dw-hdma-v0-regs.h"
> +#include "dw-edma-core.h"
> +
> +#define REGS_ADDR(name) \
> + ((void __force *)&regs->name)
> +
> +#define REGISTER(name) \
> + { #name, REGS_ADDR(name) }
> +
> +#define WRITE_STR "write"
> +#define READ_STR "read"
> +#define CHANNEL_STR "channel"
> +#define REGISTERS_STR "registers"
> +
> +static struct dw_edma *dw;
> +static struct dw_hdma_v0_regs __iomem *regs;

Empty line please.

> +struct debugfs_entries {
> + const char *name;
> + dma_addr_t *reg;
> +};
> +
> +static int dw_hdma_debugfs_u32_get(void *data, u64 *val)
> +{
> + void __iomem *reg = (void __force __iomem *)data;
> + *val = readl(reg);
> +
> + return 0;
> +}
> +DEFINE_DEBUGFS_ATTRIBUTE(fops_x32, dw_hdma_debugfs_u32_get, NULL, "0x%08llx\n");
> +
> +static void dw_hdma_debugfs_create_x32(const struct debugfs_entries entries[],
> + int nr_entries, struct dentry *dir)
> +{
> + int i;
> +
> + for (i = 0; i < nr_entries; i++) {
> + if (!debugfs_create_file_unsafe(entries[i].name, 0444, dir,
> + entries[i].reg, &fops_x32))
> + break;
> + }
> +}
> +
> +static void dw_hdma_debugfs_regs_ch(struct dw_hdma_v0_ch_regs __iomem *regs,
> + struct dentry *dir)
> +{
> + int nr_entries;
> + const struct debugfs_entries debugfs_regs[] = {
> + REGISTER(ch_en),
> + REGISTER(doorbell),
> + REGISTER(llp.lsb),
> + REGISTER(llp.msb),
> + REGISTER(cycle_sync),
> + REGISTER(transfer_size),
> + REGISTER(sar.lsb),
> + REGISTER(sar.msb),
> + REGISTER(dar.lsb),
> + REGISTER(dar.msb),
> + REGISTER(control1),
> + REGISTER(ch_stat),
> + REGISTER(int_stat),
> + REGISTER(int_setup),
> + REGISTER(int_clear),
> + REGISTER(msi_stop.lsb),
> + REGISTER(msi_stop.msb),
> + REGISTER(msi_abort.lsb),
> + REGISTER(msi_abort.msb),
> + REGISTER(msi_msgdata),
> + };
> +
> + nr_entries = ARRAY_SIZE(debugfs_regs);
> + dw_hdma_debugfs_create_x32(debugfs_regs, nr_entries, dir);
> +}
> +
> +static void dw_hdma_debugfs_regs_wr(struct dentry *dir)
> +{
> + struct dentry *regs_dir, *ch_dir;
> + int i;
> + char name[16];
> +
> + regs_dir = debugfs_create_dir(WRITE_STR, dir);
> + if (!regs_dir)
> + return;
> +
> + for (i = 0; i < dw->wr_ch_cnt; i++) {
> + snprintf(name, sizeof(name), "%s:%d", CHANNEL_STR, i);
> +
> + ch_dir = debugfs_create_dir(name, regs_dir);
> + if (!ch_dir)
> + return;
> +
> + dw_hdma_debugfs_regs_ch(&regs->ch[i].wr, ch_dir);
> + }
> +}
> +
> +static void dw_hdma_debugfs_regs_rd(struct dentry *dir)
> +{
> + struct dentry *regs_dir, *ch_dir;
> + int i;
> + char name[16];
> +
> + regs_dir = debugfs_create_dir(READ_STR, dir);
> + if (!regs_dir)
> + return;
> +
> + for (i = 0; i < dw->rd_ch_cnt; i++) {
> + snprintf(name, sizeof(name), "%s:%d", CHANNEL_STR, i);
> +
> + ch_dir = debugfs_create_dir(name, regs_dir);
> + if (!ch_dir)
> + return;
> +
> + dw_hdma_debugfs_regs_ch(&regs->ch[i].rd, ch_dir);
> + }
> +}
> +
> +static void dw_hdma_debugfs_regs(void)
> +{
> + struct dentry *regs_dir;
> +
> + regs_dir = debugfs_create_dir(REGISTERS_STR, dw->dma.dbg_dev_root);
> + if (!regs_dir)
> + return;
> +
> + dw_hdma_debugfs_regs_wr(regs_dir);
> + dw_hdma_debugfs_regs_rd(regs_dir);
> +}
> +
> +void dw_hdma_v0_debugfs_on(struct dw_edma *dw)
> +{
> + if (!debugfs_initialized())
> + return;
> +
> + debugfs_create_u32("mf", 0444, dw->dma.dbg_dev_root, &dw->chip->mf);
> + debugfs_create_u16("wr_ch_cnt", 0444, dw->dma.dbg_dev_root, &dw->wr_ch_cnt);
> + debugfs_create_u16("rd_ch_cnt", 0444, dw->dma.dbg_dev_root, &dw->rd_ch_cnt);
> +
> + dw_hdma_debugfs_regs();
> +}
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-debugfs.h b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.h
> new file mode 100644
> index 000000000000..4b70911aedac
> --- /dev/null
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.h
> @@ -0,0 +1,22 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2022 Cai Huoqing
> + * Synopsys DesignWare HDMA v0 debugfs
> + *
> + * Author: Cai Huoqing <cai.huoqing@xxxxxxxxx>
> + */
> +
> +#ifndef _DW_HDMA_V0_DEBUG_FS_H
> +#define _DW_HDMA_V0_DEBUG_FS_H
> +
> +#include <linux/dma/edma.h>
> +
> +#ifdef CONFIG_DEBUG_FS
> +void dw_hdma_v0_debugfs_on(struct dw_edma *dw);
> +#else
> +static inline void dw_hdma_v0_debugfs_on(struct dw_edma *dw)
> +{
> +}
> +#endif /* CONFIG_DEBUG_FS */
> +
> +#endif /* _DW_HDMA_V0_DEBUG_FS_H */
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-regs.h b/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> new file mode 100644
> index 000000000000..677bf44400b3
> --- /dev/null
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> @@ -0,0 +1,98 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2022 Cai Huoqing
> + * Synopsys DesignWare HDMA v0 reg
> + *
> + * Author: Cai Huoqing <cai.huoqing@xxxxxxxxx>
> + */
> +
> +#ifndef _DW_HDMA_V0_REGS_H
> +#define _DW_HDMA_V0_REGS_H
> +
> +#include <linux/dmaengine.h>
> +

> +#define HDMA_V0_MAX_NR_CH 8

Remove one redundant tab

> +#define HDMA_V0_LOCAL_ABORT_INT_EN BIT(6)
> +#define HDMA_V0_REMOTE_ABORT_INT_EN BIT(5)
> +#define HDMA_V0_LOCAL_STOP_INT_EN BIT(4)
> +#define HDMA_V0_REMOTEL_STOP_INT_EN BIT(3)
> +#define HDMA_V0_ABORT_INT_MASK BIT(2)
> +#define HDMA_V0_STOP_INT_MASK BIT(0)

> +#define HDMA_V0_LINKLIST_EN BIT(0)

ditto

> +#define HDMA_V0_CONSUMER_CYCLE_STAT BIT(1)
> +#define HDMA_V0_CONSUMER_CYCLE_BIT BIT(0)
> +#define HDMA_V0_DOORBELL_START BIT(0)
> +#define HDMA_V0_CH_STATUS_MASK GENMASK(1, 0)
> +

> +struct dw_hdma_v0_ch_regs {
> + u32 ch_en; /* 0x0000 */

Please make sure all the inline comments are aligned along a single
vertical line. The comments jump out of line here and there.

> + u32 doorbell; /* 0x0004 */
> + u32 prefetch; /* 0x0008 */
> + u32 handshake; /* 0x000c */
> + union {
> + u64 reg; /* 0x0010..0x0014 */
> + struct {
> + u32 lsb; /* 0x0010 */
> + u32 msb; /* 0x0014 */
> + };
> + } llp;
> + u32 cycle_sync; /* 0x0018 */
> + u32 transfer_size; /* 0x001c */
> + union {
> + u64 reg; /* 0x0020..0x0024 */
> + struct {
> + u32 lsb; /* 0x0020 */
> + u32 msb; /* 0x0024 */
> + };
> + } sar;
> + union {
> + u64 reg; /* 0x0028..0x002c */
> + struct {
> + u32 lsb; /* 0x0028 */
> + u32 msb; /* 0x002c */
> + };
> + } dar;
> +
> + u32 watermark_en; /* 0x0030 */

> + u32 control1; /* 0x0034 */
> + u32 func_num; /* 0x0038 */
> + u32 qos; /* 0x003c */
> + u32 reserved; /* 0x0040..0x007c */

Use spaces instead of tabs in the field declaration in the same way
as it's done for the rest of the fields.

> + u32 ch_stat; /* 0x0080 */
> + u32 int_stat; /* 0x0084 */
> + u32 int_setup; /* 0x0088 */
> + u32 int_clear; /* 0x008c */
> + union {
> + u64 reg; /* 0x0090..0x0094 */
> + struct {
> + u32 lsb; /* 0x0090 */
> + u32 msb; /* 0x0094 */
> + };
> + } msi_stop;
> + union {
> + u64 reg; /* 0x0098..0x009c */
> + struct {
> + u32 lsb; /* 0x0098 */
> + u32 msb; /* 0x009c */
> + };
> + } msi_watermark;
> + union {
> + u64 reg; /* 0x00a0..0x00a4 */
> + struct {
> + u32 lsb; /* 0x00a0 */
> + u32 msb; /* 0x00a4 */
> + };
> + } msi_abort;

> + u32 msi_msgdata; /* 0x00a8 */

ditto

> +} __packed;
> +
> +struct dw_hdma_v0_ch {
> + struct dw_hdma_v0_ch_regs wr; /* 0x0000 */
> + struct dw_hdma_v0_ch_regs rd; /* 0x0100 */
> +} __packed;
> +
> +struct dw_hdma_v0_regs {
> + struct dw_hdma_v0_ch ch[HDMA_V0_MAX_NR_CH]; /* 0x0000..0x0fa8 */
> +} __packed;
> +
> +#endif /* _DW_HDMA_V0_REGS_H */
> diff --git a/include/linux/dma/edma.h b/include/linux/dma/edma.h
> index 642dd325259b..b879d107f08b 100644
> --- a/include/linux/dma/edma.h
> +++ b/include/linux/dma/edma.h
> @@ -45,7 +45,8 @@ struct dw_edma_plat_ops {
> enum dw_edma_map_format {
> EDMA_MF_EDMA_LEGACY = 0x0,
> EDMA_MF_EDMA_UNROLL = 0x1,
> - EDMA_MF_HDMA_COMPAT = 0x5
> + EDMA_MF_HDMA_COMPAT = 0x5,

> + EDMA_MF_HDMA_NATIVE = 0x7

Please add terminating comma here.

-Serge(y)

> };
>
> /**
> --
> 2.25.1
>