[PATCH v4 4/4] dmaengine: dw-edma: Add HDMA DebugFS support

From: Cai Huoqing
Date: Mon Feb 20 2023 - 22:48:02 EST


From: Cai huoqing <cai.huoqing@xxxxxxxxx>

Add HDMA DebugFS support to show register information

Signed-off-by: Cai huoqing <cai.huoqing@xxxxxxxxx>
---
v3->v4:
1.Add field watermark_en, func_num, qos, msi_watermark,etc.
2.Make variables reverse xmas tree order.
3.Declare const for 'struct dw_hdma_debugfs_entry'

v3 link:
https://lore.kernel.org/lkml/20230213132411.65524-5-cai.huoqing@xxxxxxxxx/

drivers/dma/dw-edma/Makefile | 3 +-
drivers/dma/dw-edma/dw-hdma-v0-core.c | 2 +
drivers/dma/dw-edma/dw-hdma-v0-debugfs.c | 181 +++++++++++++++++++++++
drivers/dma/dw-edma/dw-hdma-v0-debugfs.h | 22 +++
4 files changed, 207 insertions(+), 1 deletion(-)
create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
create mode 100644 drivers/dma/dw-edma/dw-hdma-v0-debugfs.h

diff --git a/drivers/dma/dw-edma/Makefile b/drivers/dma/dw-edma/Makefile
index b1c91ef2c63d..83ab58f87760 100644
--- a/drivers/dma/dw-edma/Makefile
+++ b/drivers/dma/dw-edma/Makefile
@@ -1,7 +1,8 @@
# 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-hdma-v0-core.o $(dw-edma-y)
diff --git a/drivers/dma/dw-edma/dw-hdma-v0-core.c b/drivers/dma/dw-edma/dw-hdma-v0-core.c
index cadc80dc62b2..6850042dbbe0 100644
--- a/drivers/dma/dw-edma/dw-hdma-v0-core.c
+++ b/drivers/dma/dw-edma/dw-hdma-v0-core.c
@@ -10,6 +10,7 @@
#include "dw-edma-core.h"
#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),
@@ -282,6 +283,7 @@ static void dw_hdma_v0_core_ch_config(struct dw_edma_chan *chan)
/* HDMA 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 dw_hdma_v0_core = {
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..3a6f70173a03
--- /dev/null
+++ b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
@@ -0,0 +1,181 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2023 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(dw, name) \
+ ({ \
+ struct dw_hdma_v0_regs __iomem *__regs = (dw)->chip->reg_base; \
+ \
+ (void __iomem *)&__regs->name; \
+ })
+
+#define REGS_CH_ADDR(dw, name, _dir, _ch) \
+ ({ \
+ struct dw_hdma_v0_ch_regs __iomem *__ch_regs; \
+ \
+ if (_dir == EDMA_DIR_READ) \
+ __ch_regs = REGS_ADDR(dw, ch[_ch].rd); \
+ else \
+ __ch_regs = REGS_ADDR(dw, ch[_ch].wr); \
+ \
+ (void __iomem *)&__ch_regs->name; \
+ })
+
+#define CTX_REGISTER(dw, name, dir, ch) \
+ { dw, #name, REGS_CH_ADDR(dw, name, dir, ch), dir, ch }
+
+#define REGISTER(dw, name) \
+ { dw, #name, REGS_ADDR(dw, name) }
+
+#define WRITE_STR "write"
+#define READ_STR "read"
+#define CHANNEL_STR "channel"
+#define REGISTERS_STR "registers"
+
+struct dw_hdma_debugfs_entry {
+ struct dw_edma *dw;
+ const char *name;
+ void __iomem *reg;
+ enum dw_edma_dir dir;
+ u16 ch;
+};
+
+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(struct dw_edma *dw,
+ const struct dw_hdma_debugfs_entry ini[],
+ int nr_entries, struct dentry *dent)
+{
+ struct dw_hdma_debugfs_entry *entries;
+ int i;
+
+ entries = devm_kcalloc(dw->chip->dev, nr_entries, sizeof(*entries),
+ GFP_KERNEL);
+ for (i = 0; i < nr_entries; i++) {
+ entries[i] = ini[i];
+
+ debugfs_create_file_unsafe(entries[i].name, 0444, dent,
+ &entries[i], &fops_x32);
+ }
+}
+
+static void dw_hdma_debugfs_regs_ch(struct dw_edma *dw, enum dw_edma_dir dir,
+ u16 ch, struct dentry *dent)
+{
+ const struct dw_hdma_debugfs_entry debugfs_regs[] = {
+ CTX_REGISTER(dw, ch_en, dir, ch),
+ CTX_REGISTER(dw, doorbell, dir, ch),
+ CTX_REGISTER(dw, prefetch, dir, ch),
+ CTX_REGISTER(dw, handshake, dir, ch),
+ CTX_REGISTER(dw, llp.lsb, dir, ch),
+ CTX_REGISTER(dw, llp.msb, dir, ch),
+ CTX_REGISTER(dw, cycle_sync, dir, ch),
+ CTX_REGISTER(dw, transfer_size, dir, ch),
+ CTX_REGISTER(dw, sar.lsb, dir, ch),
+ CTX_REGISTER(dw, sar.msb, dir, ch),
+ CTX_REGISTER(dw, dar.lsb, dir, ch),
+ CTX_REGISTER(dw, dar.msb, dir, ch),
+ CTX_REGISTER(dw, watermark_en, dir, ch),
+ CTX_REGISTER(dw, control1, dir, ch),
+ CTX_REGISTER(dw, func_num, dir, ch),
+ CTX_REGISTER(dw, qos, dir, ch),
+ CTX_REGISTER(dw, ch_stat, dir, ch),
+ CTX_REGISTER(dw, int_stat, dir, ch),
+ CTX_REGISTER(dw, int_setup, dir, ch),
+ CTX_REGISTER(dw, int_clear, dir, ch),
+ CTX_REGISTER(dw, msi_stop.lsb, dir, ch),
+ CTX_REGISTER(dw, msi_stop.msb, dir, ch),
+ CTX_REGISTER(dw, msi_watermark.lsb, dir, ch),
+ CTX_REGISTER(dw, msi_watermark.msb, dir, ch),
+ CTX_REGISTER(dw, msi_abort.lsb, dir, ch),
+ CTX_REGISTER(dw, msi_abort.msb, dir, ch),
+ CTX_REGISTER(dw, msi_msgdata, dir, ch),
+ };
+ int nr_entries = ARRAY_SIZE(debugfs_regs);
+
+ dw_hdma_debugfs_create_x32(dw, debugfs_regs, nr_entries, dent);
+}
+
+static void dw_hdma_debugfs_regs_wr(struct dw_edma *dw, struct dentry *dent)
+{
+ struct dentry *regs_dent, *ch_dent;
+ char name[16];
+ int i;
+
+ regs_dent = debugfs_create_dir(WRITE_STR, dent);
+ if (!regs_dent)
+ return;
+
+ for (i = 0; i < dw->wr_ch_cnt; i++) {
+ snprintf(name, sizeof(name), "%s:%d", CHANNEL_STR, i);
+
+ ch_dent = debugfs_create_dir(name, regs_dent);
+ if (!ch_dent)
+ return;
+
+ dw_hdma_debugfs_regs_ch(dw, EDMA_DIR_WRITE, i, ch_dent);
+ }
+}
+
+static void dw_hdma_debugfs_regs_rd(struct dw_edma *dw, struct dentry *dent)
+{
+ struct dentry *regs_dent, *ch_dent;
+ char name[16];
+ int i;
+
+ regs_dent = debugfs_create_dir(READ_STR, dent);
+ if (!regs_dent)
+ return;
+
+ for (i = 0; i < dw->rd_ch_cnt; i++) {
+ snprintf(name, sizeof(name), "%s:%d", CHANNEL_STR, i);
+
+ ch_dent = debugfs_create_dir(name, regs_dent);
+ if (!ch_dent)
+ return;
+
+ dw_hdma_debugfs_regs_ch(dw, EDMA_DIR_READ, i, ch_dent);
+ }
+}
+
+static void dw_hdma_debugfs_regs(struct dw_edma *dw)
+{
+ struct dentry *regs_dent;
+
+ regs_dent = debugfs_create_dir(REGISTERS_STR, dw->dma.dbg_dev_root);
+ if (!regs_dent)
+ return;
+
+ dw_hdma_debugfs_regs_wr(dw, regs_dent);
+ dw_hdma_debugfs_regs_rd(dw, regs_dent);
+}
+
+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(dw);
+}
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..e6842c83777d
--- /dev/null
+++ b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2023 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 */
--
2.34.1