On Tue, Feb 21, 2023 at 11:46:55AM +0800, Cai Huoqing wrote: > 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); A tiny nitpick. Please add newline between the lines above so the code would look a bit cleaner. > + > + 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); Make sure devm_kcalloc() returns not-null. https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/tree/drivers/dma/dw-edma/dw-edma-v0-debugfs.c?h=controller/dwc#n108 otherwise you risk to catch the null-dereference. > + 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; No need in this check. DebugFS is designed to silently skip the nodes creation if for some reason the parental dir couldn't be created: https://elixir.bootlin.com/linux/latest/source/fs/debugfs/inode.c#L422 That's why the check was omitted in the eDMA part: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/tree/drivers/dma/dw-edma/dw-edma-v0-debugfs.c?h=controller/dwc#n181 > + > + 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; ditto > + > + 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; ditto -Serge(y) > + > + 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 >
