diff mbox series

[RFC,v4,3/6] dmaengine: Add Synopsys eDMA IP version 0 debugfs support

Message ID 5b190f6276cd9b67fa7c23ff0669df670e69b265.1549904495.git.gustavo.pimentel@synopsys.com (mailing list archive)
State RFC
Headers show
Series dmaengine: Add Synopsys eDMA IP driver (version 0) | expand

Commit Message

Gustavo Pimentel Feb. 11, 2019, 5:03 p.m. UTC 
Add Synopsys eDMA IP version 0 debugfs support to assist any debug
in the future.

Creates a file system structure composed by folders and files that mimic
the IP register map (this files are read only) to ease any debug.

To enable this feature is necessary to select DEBUG_FS option on kernel
configuration.

Small output example:

(eDMA IP version 0, unroll, 1 write + 1 read channels)

% mount -t debugfs none /sys/kernel/debug/
% tree /sys/kernel/debug/dw-edma-core:0/
dw-edma/
├── version
├── mode
├── wr_ch_cnt
├── rd_ch_cnt
└── registers
    ├── ctrl_data_arb_prior
    ├── ctrl
    ├── write
    │   ├── engine_en
    │   ├── doorbell
    │   ├── ch_arb_weight_low
    │   ├── ch_arb_weight_high
    │   ├── int_status
    │   ├── int_mask
    │   ├── int_clear
    │   ├── err_status
    │   ├── done_imwr_low
    │   ├── done_imwr_high
    │   ├── abort_imwr_low
    │   ├── abort_imwr_high
    │   ├── ch01_imwr_data
    │   ├── ch23_imwr_data
    │   ├── ch45_imwr_data
    │   ├── ch67_imwr_data
    │   ├── linked_list_err_en
    │   ├── engine_chgroup
    │   ├── engine_hshake_cnt_low
    │   ├── engine_hshake_cnt_high
    │   ├── ch0_pwr_en
    │   ├── ch1_pwr_en
    │   ├── ch2_pwr_en
    │   ├── ch3_pwr_en
    │   ├── ch4_pwr_en
    │   ├── ch5_pwr_en
    │   ├── ch6_pwr_en
    │   ├── ch7_pwr_en
    │   └── channel:0
    │       ├── ch_control1
    │       ├── ch_control2
    │       ├── transfer_size
    │       ├── sar_low
    │       ├── sar_high
    │       ├── dar_high
    │       ├── llp_low
    │       └── llp_high
    └── read
        ├── engine_en
        ├── doorbell
        ├── ch_arb_weight_low
        ├── ch_arb_weight_high
        ├── int_status
        ├── int_mask
        ├── int_clear
        ├── err_status_low
        ├── err_status_high
        ├── done_imwr_low
        ├── done_imwr_high
        ├── abort_imwr_low
        ├── abort_imwr_high
        ├── ch01_imwr_data
        ├── ch23_imwr_data
        ├── ch45_imwr_data
        ├── ch67_imwr_data
        ├── linked_list_err_en
        ├── engine_chgroup
        ├── engine_hshake_cnt_low
        ├── engine_hshake_cnt_high
        ├── ch0_pwr_en
        ├── ch1_pwr_en
        ├── ch2_pwr_en
        ├── ch3_pwr_en
        ├── ch4_pwr_en
        ├── ch5_pwr_en
        ├── ch6_pwr_en
        ├── ch7_pwr_en
        └── channel:0
            ├── ch_control1
            ├── ch_control2
            ├── transfer_size
            ├── sar_low
            ├── sar_high
            ├── dar_high
            ├── llp_low
            └── llp_high

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Eugeniy Paltsev <paltsev@synopsys.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Niklas Cassel <niklas.cassel@linaro.org>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Jose Abreu <jose.abreu@synopsys.com>
Cc: Luis Oliveira <lolivei@synopsys.com>
Cc: Vitor Soares <vitor.soares@synopsys.com>
Cc: Nelson Costa <nelson.costa@synopsys.com>
Cc: Pedro Sousa <pedrom.sousa@synopsys.com>
diff mbox series

Patch

diff --git a/drivers/dma/dw-edma/Makefile b/drivers/dma/dw-edma/Makefile
index 01c7c63..0c53033 100644
--- a/drivers/dma/dw-edma/Makefile
+++ b/drivers/dma/dw-edma/Makefile
@@ -1,5 +1,6 @@ 
 # 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-objs			:= dw-edma-core.o \
-					dw-edma-v0-core.o
+					dw-edma-v0-core.o $(dw-edma-y)
diff --git a/drivers/dma/dw-edma/dw-edma-v0-core.c b/drivers/dma/dw-edma/dw-edma-v0-core.c
index 101e3f3..0925c7f 100644
--- a/drivers/dma/dw-edma/dw-edma-v0-core.c
+++ b/drivers/dma/dw-edma/dw-edma-v0-core.c
@@ -337,9 +337,10 @@  int dw_edma_v0_core_device_config(struct dw_edma_chan *chan)
 /* eDMA debugfs callbacks */
 int dw_edma_v0_core_debugfs_on(struct dw_edma_chip *chip)
 {
-	return 0;
+	return dw_edma_v0_debugfs_on(chip);
 }
 
 void dw_edma_v0_core_debugfs_off(void)
 {
+	dw_edma_v0_debugfs_off();
 }
diff --git a/drivers/dma/dw-edma/dw-edma-v0-debugfs.c b/drivers/dma/dw-edma/dw-edma-v0-debugfs.c
new file mode 100644
index 0000000..cddfadc
--- /dev/null
+++ b/drivers/dma/dw-edma/dw-edma-v0-debugfs.c
@@ -0,0 +1,359 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2019 Synopsys, Inc. and/or its affiliates.
+ * Synopsys DesignWare eDMA v0 core
+ */
+
+#include <linux/debugfs.h>
+#include <linux/bitfield.h>
+
+#include "dw-edma-v0-debugfs.h"
+#include "dw-edma-v0-regs.h"
+#include "dw-edma-core.h"
+
+#define RD_PERM					0444
+
+#define REGS_ADDR(name) \
+	((dma_addr_t *)&regs->name)
+#define REGISTER(name) \
+	{ #name, REGS_ADDR(name) }
+
+#define WR_REGISTER(name) \
+	{ #name, REGS_ADDR(wr_##name) }
+#define RD_REGISTER(name) \
+	{ #name, REGS_ADDR(rd_##name) }
+
+#define WR_REGISTER_LEGACY(name) \
+	{ #name, REGS_ADDR(type.legacy.wr_##name) }
+#define RD_REGISTER_LEGACY(name) \
+	{ #name, REGS_ADDR(type.legacy.rd_##name) }
+
+#define WR_REGISTER_UNROLL(name) \
+	{ #name, REGS_ADDR(type.unroll.wr_##name) }
+#define RD_REGISTER_UNROLL(name) \
+	{ #name, REGS_ADDR(type.unroll.rd_##name) }
+
+#define WRITE_STR				"write"
+#define READ_STR				"read"
+#define CHANNEL_STR				"channel"
+#define REGISTERS_STR				"registers"
+
+static struct dentry				*base_dir;
+static struct dw_edma				*dw;
+static struct dw_edma_v0_regs			*regs;
+
+static struct {
+	void					*start;
+	void					*end;
+} lim[2][EDMA_V0_MAX_NR_CH];
+
+struct debugfs_entries {
+	char					name[24];
+	dma_addr_t				*reg;
+};
+
+static int dw_edma_debugfs_u32_get(void *data, u64 *val)
+{
+	if (dw->mode == EDMA_MODE_LEGACY &&
+	    data >= (void *)&regs->type.legacy.ch) {
+		void *ptr = (void *)&regs->type.legacy.ch;
+		u32 viewport_sel = 0;
+		unsigned long flags;
+		u16 ch;
+
+		for (ch = 0; ch < dw->wr_ch_cnt; ch++)
+			if (lim[0][ch].start >= data && data < lim[0][ch].end) {
+				ptr += (data - lim[0][ch].start);
+				goto legacy_sel_wr;
+			}
+
+		for (ch = 0; ch < dw->rd_ch_cnt; ch++)
+			if (lim[1][ch].start >= data && data < lim[1][ch].end) {
+				ptr += (data - lim[1][ch].start);
+				goto legacy_sel_rd;
+			}
+
+		return 0;
+legacy_sel_rd:
+		viewport_sel = BIT(31);
+legacy_sel_wr:
+		viewport_sel |= FIELD_PREP(EDMA_V0_VIEWPORT_MASK, ch);
+
+		raw_spin_lock_irqsave(&dw->lock, flags);
+
+		writel(viewport_sel, &regs->type.legacy.viewport_sel);
+		*val = readl((u32 *)ptr);
+
+		raw_spin_unlock_irqrestore(&dw->lock, flags);
+	} else {
+		*val = readl((u32 *)data);
+	}
+
+	return 0;
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fops_x32, dw_edma_debugfs_u32_get, NULL, "0x%08llx\n");
+
+static int dw_edma_debugfs_create_x32(const struct debugfs_entries entries[],
+				      int nr_entries, struct dentry *dir)
+{
+	struct dentry *entry;
+	int i;
+
+	for (i = 0; i < nr_entries; i++) {
+		entry = debugfs_create_file_unsafe(entries[i].name, RD_PERM,
+						   dir, entries[i].reg,
+						   &fops_x32);
+		if (!entry)
+			return -EPERM;
+	}
+
+	return 0;
+}
+
+static int dw_edma_debugfs_regs_ch(struct dw_edma_v0_ch_regs *regs,
+				   struct dentry *dir)
+{
+	int nr_entries;
+	const struct debugfs_entries debugfs_regs[] = {
+		REGISTER(ch_control1),
+		REGISTER(ch_control2),
+		REGISTER(transfer_size),
+		REGISTER(sar_low),
+		REGISTER(sar_high),
+		REGISTER(dar_low),
+		REGISTER(dar_high),
+		REGISTER(llp_low),
+		REGISTER(llp_high),
+	};
+
+	nr_entries = ARRAY_SIZE(debugfs_regs);
+	return dw_edma_debugfs_create_x32(debugfs_regs, nr_entries, dir);
+}
+
+static int dw_edma_debugfs_regs_wr(struct dentry *dir)
+{
+	const struct debugfs_entries debugfs_regs[] = {
+		/* eDMA global registers */
+		WR_REGISTER(engine_en),
+		WR_REGISTER(doorbell),
+		WR_REGISTER(ch_arb_weight_low),
+		WR_REGISTER(ch_arb_weight_high),
+		/* eDMA interrupts registers */
+		WR_REGISTER(int_status),
+		WR_REGISTER(int_mask),
+		WR_REGISTER(int_clear),
+		WR_REGISTER(err_status),
+		WR_REGISTER(done_imwr_low),
+		WR_REGISTER(done_imwr_high),
+		WR_REGISTER(abort_imwr_low),
+		WR_REGISTER(abort_imwr_high),
+		WR_REGISTER(ch01_imwr_data),
+		WR_REGISTER(ch23_imwr_data),
+		WR_REGISTER(ch45_imwr_data),
+		WR_REGISTER(ch67_imwr_data),
+		WR_REGISTER(linked_list_err_en),
+	};
+	const struct debugfs_entries debugfs_unroll_regs[] = {
+		/* eDMA channel context grouping */
+		WR_REGISTER_UNROLL(engine_chgroup),
+		WR_REGISTER_UNROLL(engine_hshake_cnt_low),
+		WR_REGISTER_UNROLL(engine_hshake_cnt_high),
+		WR_REGISTER_UNROLL(ch0_pwr_en),
+		WR_REGISTER_UNROLL(ch1_pwr_en),
+		WR_REGISTER_UNROLL(ch2_pwr_en),
+		WR_REGISTER_UNROLL(ch3_pwr_en),
+		WR_REGISTER_UNROLL(ch4_pwr_en),
+		WR_REGISTER_UNROLL(ch5_pwr_en),
+		WR_REGISTER_UNROLL(ch6_pwr_en),
+		WR_REGISTER_UNROLL(ch7_pwr_en),
+	};
+	struct dentry *regs_dir, *ch_dir;
+	int nr_entries, i, err;
+	char name[16];
+
+	regs_dir = debugfs_create_dir(WRITE_STR, dir);
+	if (!regs_dir)
+		return -EPERM;
+
+	nr_entries = ARRAY_SIZE(debugfs_regs);
+	err = dw_edma_debugfs_create_x32(debugfs_regs, nr_entries, regs_dir);
+	if (err)
+		return err;
+
+	if (dw->mode == EDMA_MODE_UNROLL) {
+		nr_entries = ARRAY_SIZE(debugfs_unroll_regs);
+		err = dw_edma_debugfs_create_x32(debugfs_unroll_regs,
+						 nr_entries, regs_dir);
+		if (err)
+			return err;
+	}
+
+	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 -EPERM;
+
+		err = dw_edma_debugfs_regs_ch(&regs->type.unroll.ch[i].wr,
+					      ch_dir);
+		if (err)
+			return err;
+
+		lim[0][i].start = &regs->type.unroll.ch[i].wr;
+		lim[0][i].end = &regs->type.unroll.ch[i].padding_1[0];
+	}
+
+	return 0;
+}
+
+static int dw_edma_debugfs_regs_rd(struct dentry *dir)
+{
+	const struct debugfs_entries debugfs_regs[] = {
+		/* eDMA global registers */
+		RD_REGISTER(engine_en),
+		RD_REGISTER(doorbell),
+		RD_REGISTER(ch_arb_weight_low),
+		RD_REGISTER(ch_arb_weight_high),
+		/* eDMA interrupts registers */
+		RD_REGISTER(int_status),
+		RD_REGISTER(int_mask),
+		RD_REGISTER(int_clear),
+		RD_REGISTER(err_status_low),
+		RD_REGISTER(err_status_high),
+		RD_REGISTER(linked_list_err_en),
+		RD_REGISTER(done_imwr_low),
+		RD_REGISTER(done_imwr_high),
+		RD_REGISTER(abort_imwr_low),
+		RD_REGISTER(abort_imwr_high),
+		RD_REGISTER(ch01_imwr_data),
+		RD_REGISTER(ch23_imwr_data),
+		RD_REGISTER(ch45_imwr_data),
+		RD_REGISTER(ch67_imwr_data),
+	};
+	const struct debugfs_entries debugfs_unroll_regs[] = {
+		/* eDMA channel context grouping */
+		RD_REGISTER_UNROLL(engine_chgroup),
+		RD_REGISTER_UNROLL(engine_hshake_cnt_low),
+		RD_REGISTER_UNROLL(engine_hshake_cnt_high),
+		RD_REGISTER_UNROLL(ch0_pwr_en),
+		RD_REGISTER_UNROLL(ch1_pwr_en),
+		RD_REGISTER_UNROLL(ch2_pwr_en),
+		RD_REGISTER_UNROLL(ch3_pwr_en),
+		RD_REGISTER_UNROLL(ch4_pwr_en),
+		RD_REGISTER_UNROLL(ch5_pwr_en),
+		RD_REGISTER_UNROLL(ch6_pwr_en),
+		RD_REGISTER_UNROLL(ch7_pwr_en),
+	};
+	struct dentry *regs_dir, *ch_dir;
+	int nr_entries, i, err;
+	char name[16];
+
+	regs_dir = debugfs_create_dir(READ_STR, dir);
+	if (!regs_dir)
+		return -EPERM;
+
+	nr_entries = ARRAY_SIZE(debugfs_regs);
+	err = dw_edma_debugfs_create_x32(debugfs_regs, nr_entries, regs_dir);
+	if (err)
+		return err;
+
+	if (dw->mode == EDMA_MODE_UNROLL) {
+		nr_entries = ARRAY_SIZE(debugfs_unroll_regs);
+		err = dw_edma_debugfs_create_x32(debugfs_unroll_regs,
+						 nr_entries, regs_dir);
+		if (err)
+			return err;
+	}
+
+	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 -EPERM;
+
+		err = dw_edma_debugfs_regs_ch(&regs->type.unroll.ch[i].rd,
+					      ch_dir);
+		if (err)
+			return err;
+
+		lim[1][i].start = &regs->type.unroll.ch[i].rd;
+		lim[1][i].end = &regs->type.unroll.ch[i].padding_2[0];
+	}
+
+	return 0;
+}
+
+static int dw_edma_debugfs_regs(void)
+{
+	const struct debugfs_entries debugfs_regs[] = {
+		REGISTER(ctrl_data_arb_prior),
+		REGISTER(ctrl),
+	};
+	struct dentry *regs_dir;
+	int nr_entries, err;
+
+	regs_dir = debugfs_create_dir(REGISTERS_STR, base_dir);
+	if (!regs_dir)
+		return -EPERM;
+
+	nr_entries = ARRAY_SIZE(debugfs_regs);
+	err = dw_edma_debugfs_create_x32(debugfs_regs, nr_entries, regs_dir);
+	if (err)
+		return err;
+
+	err = dw_edma_debugfs_regs_wr(regs_dir);
+	if (err)
+		return err;
+
+	err = dw_edma_debugfs_regs_rd(regs_dir);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+int dw_edma_v0_debugfs_on(struct dw_edma_chip *chip)
+{
+	struct dentry *entry;
+	int err;
+
+	dw = chip->dw;
+	if (!dw)
+		return -EPERM;
+
+	regs = (struct dw_edma_v0_regs *)dw->rg_region.vaddr;
+	if (!regs)
+		return -EPERM;
+
+	base_dir = debugfs_create_dir(dw->name, 0);
+	if (!base_dir)
+		return -EPERM;
+
+	entry = debugfs_create_u32("version", RD_PERM, base_dir, &dw->version);
+	if (!entry)
+		return -EPERM;
+
+	entry = debugfs_create_u32("mode", RD_PERM, base_dir, &dw->mode);
+	if (!entry)
+		return -EPERM;
+
+	entry = debugfs_create_u16("wr_ch_cnt", RD_PERM, base_dir,
+				   &dw->wr_ch_cnt);
+	if (!entry)
+		return -EPERM;
+
+	entry = debugfs_create_u16("rd_ch_cnt", RD_PERM, base_dir,
+				   &dw->rd_ch_cnt);
+	if (!entry)
+		return -EPERM;
+
+	err = dw_edma_debugfs_regs();
+	return err;
+}
+
+void dw_edma_v0_debugfs_off(void)
+{
+	debugfs_remove_recursive(base_dir);
+}
diff --git a/drivers/dma/dw-edma/dw-edma-v0-debugfs.h b/drivers/dma/dw-edma/dw-edma-v0-debugfs.h
new file mode 100644
index 0000000..12c4a96
--- /dev/null
+++ b/drivers/dma/dw-edma/dw-edma-v0-debugfs.h
@@ -0,0 +1,26 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2018-2019 Synopsys, Inc. and/or its affiliates.
+ * Synopsys DesignWare eDMA v0 core
+ */
+
+#ifndef _DW_EDMA_V0_DEBUG_FS_H
+#define _DW_EDMA_V0_DEBUG_FS_H
+
+#include <linux/dma/edma.h>
+
+#ifdef CONFIG_DEBUG_FS
+int dw_edma_v0_debugfs_on(struct dw_edma_chip *chip);
+void dw_edma_v0_debugfs_off(void);
+#else
+static inline int dw_edma_v0_debugfs_on(struct dw_edma_chip *chip)
+{
+	return 0;
+}
+
+static inline void dw_edma_v0_debugfs_off(void)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+#endif /* _DW_EDMA_V0_DEBUG_FS_H */