[PATCH v6 2/3] dmaengine: fsl-emda: add debugfs support

[Frank Li]

Add debugfs support to fsl-edma to enable dumping of register states.

Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
 drivers/dma/Makefile           |   5 +-
 drivers/dma/fsl-edma-common.h  |   8 ++
 drivers/dma/fsl-edma-debugfs.c | 200 +++++++++++++++++++++++++++++++++
 drivers/dma/fsl-edma-main.c    |   2 +
 4 files changed, 213 insertions(+), 2 deletions(-)
 create mode 100644 drivers/dma/fsl-edma-debugfs.c

diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 83553a97a010..a51c6397bcad 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -31,10 +31,11 @@ obj-$(CONFIG_DW_AXI_DMAC) += dw-axi-dmac/
 obj-$(CONFIG_DW_DMAC_CORE) += dw/
 obj-$(CONFIG_DW_EDMA) += dw-edma/
 obj-$(CONFIG_EP93XX_DMA) += ep93xx_dma.o
+fsl-edma-debugfs-$(CONFIG_DEBUG_FS) := fsl-edma-debugfs.o
 obj-$(CONFIG_FSL_DMA) += fsldma.o
-fsl-edma-objs := fsl-edma-main.o fsl-edma-common.o
+fsl-edma-objs := fsl-edma-main.o fsl-edma-common.o $(fsl-edma-debugfs-y)
 obj-$(CONFIG_FSL_EDMA) += fsl-edma.o
-mcf-edma-objs := mcf-edma-main.o fsl-edma-common.o
+mcf-edma-objs := mcf-edma-main.o fsl-edma-common.o $(fsl-edma-debugfs-y)
 obj-$(CONFIG_MCF_EDMA) += mcf-edma.o
 obj-$(CONFIG_FSL_QDMA) += fsl-qdma.o
 obj-$(CONFIG_FSL_RAID) += fsl_raid.o
diff --git a/drivers/dma/fsl-edma-common.h b/drivers/dma/fsl-edma-common.h
index 3cc0cc8fc2d0..029197440bc3 100644
--- a/drivers/dma/fsl-edma-common.h
+++ b/drivers/dma/fsl-edma-common.h
@@ -336,4 +336,12 @@ void fsl_edma_free_chan_resources(struct dma_chan *chan);
 void fsl_edma_cleanup_vchan(struct dma_device *dmadev);
 void fsl_edma_setup_regs(struct fsl_edma_engine *edma);
 
+#ifdef CONFIG_DEBUG_FS
+void fsl_edma_debugfs_on(struct fsl_edma_engine *edma);
+#else
+static inline void fsl_edma_debugfs_on(struct fsl_edma_engine *edma)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
 #endif /* _FSL_EDMA_COMMON_H_ */
diff --git a/drivers/dma/fsl-edma-debugfs.c b/drivers/dma/fsl-edma-debugfs.c
new file mode 100644
index 000000000000..99f34198dae0
--- /dev/null
+++ b/drivers/dma/fsl-edma-debugfs.c
@@ -0,0 +1,200 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/debugfs.h>
+#include <linux/bitfield.h>
+
+#include "fsl-edma-common.h"
+
+#define fsl_edma_debugfs_reg(reg, b, _s, __name)	\
+do {	reg->name = __stringify(__name);		\
+	reg->offset = offsetof(struct _s, __name);	\
+	reg->size = sizeof(((struct _s *)0)->__name);	\
+	reg->bigendian = b;				\
+	reg++;						\
+} while (0)
+
+#define fsl_edma_debugfs_regv1(reg, edma, __name)	\
+do {	reg->name = __stringify(__name);		\
+	reg->offset = edma->regs.__name - edma->membase;\
+	reg->bigendian = edma->big_endian;		\
+	reg++;						\
+} while (0)
+
+static void fsl_edma_debufs_tcdreg(struct fsl_edma_chan *chan, struct dentry *dir)
+{
+	struct debugfs_regset *regset;
+	struct debugfs_reg *reg;
+	struct device *dev;
+	int be;
+
+	be = chan->edma->big_endian;
+
+	dev = &chan->pdev->dev;
+
+	regset = devm_kzalloc(dev, sizeof(*regset), GFP_KERNEL);
+	if (!regset)
+		return;
+
+	regset->dev = dev;
+	regset->base = chan->tcd;
+
+	/* sizeof(struct fsl_edma_hw_tcd)/sizeof(u16) is enough for hold all registers */
+	reg = devm_kcalloc(dev, sizeof(struct fsl_edma_hw_tcd)/sizeof(u16),
+			   sizeof(*reg), GFP_KERNEL);
+
+	if (!reg)
+		return;
+
+	regset->regs = reg;
+
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, saddr);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, soff);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, attr);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, nbytes);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, slast);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, daddr);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, doff);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, citer);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, dlast_sga);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, csr);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma_hw_tcd, biter);
+
+	regset->nregs = reg - regset->regs;
+
+	debugfs_create_regset("tcd", 0444, dir, regset);
+}
+
+static void fsl_edma3_debufs_chan(struct fsl_edma_chan *chan, struct dentry *entry)
+{
+	struct debugfs_regset *regset;
+	struct debugfs_reg *reg;
+	struct device *dev;
+	int be;
+
+	be = chan->edma->big_endian;
+
+	dev = &chan->pdev->dev;
+
+	regset = devm_kzalloc(dev, sizeof(*regset), GFP_KERNEL);
+	if (!regset)
+		return;
+
+	regset->dev = dev;
+
+	reg = devm_kcalloc(dev, sizeof(struct fsl_edma3_ch_reg)/sizeof(u32),
+			   sizeof(*reg), GFP_KERNEL);
+
+	if (!reg)
+		return;
+
+	regset->base = chan->tcd;
+	regset->base -= offsetof(struct fsl_edma3_ch_reg, tcd);
+
+	regset->regs = reg;
+
+	fsl_edma_debugfs_reg(reg, be, fsl_edma3_ch_reg, ch_csr);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma3_ch_reg, ch_es);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma3_ch_reg, ch_int);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma3_ch_reg, ch_sbr);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma3_ch_reg, ch_pri);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma3_ch_reg, ch_mux);
+	fsl_edma_debugfs_reg(reg, be, fsl_edma3_ch_reg, ch_mattr);
+
+	regset->nregs = reg - regset->regs;
+	debugfs_create_regset("regs", 0444, entry, regset);
+
+	fsl_edma_debufs_tcdreg(chan, entry);
+}
+
+static void fsl_edma3_debugfs_init(struct fsl_edma_engine *edma)
+{
+	struct fsl_edma_chan *chan;
+	struct dentry *dir;
+	int i;
+
+	for (i = 0; i < edma->n_chans; i++) {
+		if (edma->chan_masked & BIT(i))
+			continue;
+
+		chan = &edma->chans[i];
+		dir = debugfs_create_dir(chan->chan_name, edma->dma_dev.dbg_dev_root);
+
+		fsl_edma3_debufs_chan(chan, dir);
+	}
+
+}
+
+static void fsl_edma_debugfs_init(struct fsl_edma_engine *edma)
+{
+	struct debugfs_regset *regset;
+	struct fsl_edma_chan *chan;
+	struct debugfs_reg *reg;
+	struct dentry *dir;
+	struct device *dev;
+	int i;
+
+	dev = edma->dma_dev.dev;
+
+	regset = devm_kzalloc(dev, sizeof(*regset), GFP_KERNEL);
+	if (!regset)
+		return;
+
+	regset->dev = dev;
+
+	reg = devm_kcalloc(dev, sizeof(struct edma_regs)/sizeof(void *), sizeof(*reg), GFP_KERNEL);
+
+	if (!reg)
+		return;
+
+	regset->regs = reg;
+	regset->base = edma->membase;
+
+	fsl_edma_debugfs_regv1(reg, edma, cr);
+	fsl_edma_debugfs_regv1(reg, edma, es);
+	fsl_edma_debugfs_regv1(reg, edma, erqh);
+	fsl_edma_debugfs_regv1(reg, edma, erql);
+	fsl_edma_debugfs_regv1(reg, edma, eeih);
+	fsl_edma_debugfs_regv1(reg, edma, eeil);
+	fsl_edma_debugfs_regv1(reg, edma, seei);
+	fsl_edma_debugfs_regv1(reg, edma, ceei);
+	fsl_edma_debugfs_regv1(reg, edma, serq);
+	fsl_edma_debugfs_regv1(reg, edma, cerq);
+	fsl_edma_debugfs_regv1(reg, edma, cint);
+	fsl_edma_debugfs_regv1(reg, edma, cerr);
+	fsl_edma_debugfs_regv1(reg, edma, ssrt);
+	fsl_edma_debugfs_regv1(reg, edma, cdne);
+	fsl_edma_debugfs_regv1(reg, edma, inth);
+	fsl_edma_debugfs_regv1(reg, edma, errh);
+	fsl_edma_debugfs_regv1(reg, edma, errl);
+
+	regset->nregs = reg - regset->regs;
+
+	debugfs_create_regset("regs", 0444, edma->dma_dev.dbg_dev_root, regset);
+
+	for (i = 0; i < edma->n_chans; i++) {
+		if (edma->chan_masked & BIT(i))
+			continue;
+
+		chan = &edma->chans[i];
+		dir = debugfs_create_dir(chan->chan_name, edma->dma_dev.dbg_dev_root);
+
+		fsl_edma_debufs_tcdreg(chan, dir);
+	}
+}
+
+void fsl_edma_debugfs_on(struct fsl_edma_engine *edma)
+{
+	if (!debugfs_initialized())
+		return;
+
+	debugfs_create_bool("big_endian", 0444, edma->dma_dev.dbg_dev_root, &edma->big_endian);
+	debugfs_create_x64("chan_mask", 0444, edma->dma_dev.dbg_dev_root, &edma->chan_masked);
+	debugfs_create_x32("n_chans", 0444, edma->dma_dev.dbg_dev_root, &edma->n_chans);
+
+	if (edma->drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)
+		fsl_edma3_debugfs_init(edma);
+	else
+		fsl_edma_debugfs_init(edma);
+}
+
+
diff --git a/drivers/dma/fsl-edma-main.c b/drivers/dma/fsl-edma-main.c
index 63d48d046f04..029a72872821 100644
--- a/drivers/dma/fsl-edma-main.c
+++ b/drivers/dma/fsl-edma-main.c
@@ -612,6 +612,8 @@ static int fsl_edma_probe(struct platform_device *pdev)
 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
 
+	fsl_edma_debugfs_on(fsl_edma);
+
 	return 0;
 }
 
-- 
2.34.1