From: Sanjay R Mehta <sanju.mehta@xxxxxxx> Expose data about the configuration and operation of the PTDMA through debugfs entries: device name, capabilities, configuration, statistics. Signed-off-by: Sanjay R Mehta <sanju.mehta@xxxxxxx> --- drivers/dma/ptdma/Makefile | 3 +- drivers/dma/ptdma/ptdma-debugfs.c | 130 ++++++++++++++++++++++++++++++++++++++ drivers/dma/ptdma/ptdma-dev.c | 8 +++ drivers/dma/ptdma/ptdma.h | 9 +++ 4 files changed, 149 insertions(+), 1 deletion(-) create mode 100644 drivers/dma/ptdma/ptdma-debugfs.c diff --git a/drivers/dma/ptdma/Makefile b/drivers/dma/ptdma/Makefile index 6fcb4ad..60e7c10 100644 --- a/drivers/dma/ptdma/Makefile +++ b/drivers/dma/ptdma/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_AMD_PTDMA) += ptdma.o ptdma-objs := ptdma-dev.o \ - ptdma-dmaengine.o + ptdma-dmaengine.o \ + ptdma-debugfs.o ptdma-$(CONFIG_PCI) += ptdma-pci.o diff --git a/drivers/dma/ptdma/ptdma-debugfs.c b/drivers/dma/ptdma/ptdma-debugfs.c new file mode 100644 index 0000000..506c148b --- /dev/null +++ b/drivers/dma/ptdma/ptdma-debugfs.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Passthrough DMA device driver + * -- Based on the CCP driver + * + * Copyright (C) 2016,2020 Advanced Micro Devices, Inc. + * + * Author: Sanjay R Mehta <sanju.mehta@xxxxxxx> + * Author: Gary R Hook <gary.hook@xxxxxxx> + */ + +#include <linux/debugfs.h> +#include <linux/seq_file.h> + +#include "ptdma.h" + +/* DebugFS helpers */ +#define MAX_NAME_LEN 20 +#define RI_VERSION_NUM 0x0000003F + +#define RI_NUM_VQM 0x00078000 +#define RI_NVQM_SHIFT 15 + +static struct dentry *pt_debugfs_dir; +static DEFINE_MUTEX(pt_debugfs_lock); + +static int pt_debugfs_info_show(struct seq_file *s, void *p) +{ + struct pt_device *pt = s->private; + unsigned int regval; + + if (!pt) + return 0; + + seq_printf(s, "Device name: %s\n", pt->name); + seq_printf(s, " # Queues: %d\n", 1); + seq_printf(s, " # Cmds: %d\n", pt->cmd_count); + + regval = ioread32(pt->io_regs + CMD_PT_VERSION); + + seq_printf(s, " Version: %d\n", regval & RI_VERSION_NUM); + seq_puts(s, " Engines:"); + seq_puts(s, "\n"); + seq_printf(s, " Queues: %d\n", (regval & RI_NUM_VQM) >> RI_NVQM_SHIFT); + + return 0; +} + +/* + * Return a formatted buffer containing the current + * statistics of queue for PTDMA + */ +static int pt_debugfs_stats_show(struct seq_file *s, void *p) +{ + struct pt_device *pt = s->private; + + seq_printf(s, "Total Interrupts Handled: %ld\n", pt->total_interrupts); + + return 0; +} + +static int pt_debugfs_queue_show(struct seq_file *s, void *p) + +{ + struct pt_cmd_queue *cmd_q = s->private; + unsigned int regval; + + if (!cmd_q) + return 0; + + seq_printf(s, " Pass-Thru: %ld\n", cmd_q->total_pt_ops); + + regval = ioread32(cmd_q->reg_int_enable); + + seq_puts(s, " Enabled Interrupts:"); + if (regval & INT_EMPTY_QUEUE) + seq_puts(s, " EMPTY"); + if (regval & INT_QUEUE_STOPPED) + seq_puts(s, " STOPPED"); + if (regval & INT_ERROR) + seq_puts(s, " ERROR"); + if (regval & INT_COMPLETION) + seq_puts(s, " COMPLETION"); + seq_puts(s, "\n"); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(pt_debugfs_info); +DEFINE_SHOW_ATTRIBUTE(pt_debugfs_queue); +DEFINE_SHOW_ATTRIBUTE(pt_debugfs_stats); + +void ptdma_debugfs_setup(struct pt_device *pt) +{ + struct pt_cmd_queue *cmd_q; + char name[MAX_NAME_LEN + 1]; + struct dentry *debugfs_q_instance; + + if (!debugfs_initialized()) + return; + + mutex_lock(&pt_debugfs_lock); + if (!pt_debugfs_dir) + pt_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL); + mutex_unlock(&pt_debugfs_lock); + + pt->dma_dev.dbg_dev_root = debugfs_create_dir(pt->name, pt_debugfs_dir); + + debugfs_create_file("info", 0400, pt->dma_dev.dbg_dev_root, pt, + &pt_debugfs_info_fops); + + debugfs_create_file("stats", 0600, pt->dma_dev.dbg_dev_root, pt, + &pt_debugfs_stats_fops); + + cmd_q = &pt->cmd_q; + + snprintf(name, MAX_NAME_LEN - 1, "q"); + + debugfs_q_instance = + debugfs_create_dir(name, pt->dma_dev.dbg_dev_root); + + debugfs_create_file("stats", 0600, debugfs_q_instance, cmd_q, + &pt_debugfs_queue_fops); +} + +void ptdma_debugfs_destroy(struct dma_device *dma_dev) +{ + debugfs_remove_recursive(dma_dev->dbg_dev_root); + dma_dev->dbg_dev_root = NULL; +} diff --git a/drivers/dma/ptdma/ptdma-dev.c b/drivers/dma/ptdma/ptdma-dev.c index ef10be5..8b13208 100644 --- a/drivers/dma/ptdma/ptdma-dev.c +++ b/drivers/dma/ptdma/ptdma-dev.c @@ -14,6 +14,7 @@ #include <linux/pci.h> #include <linux/dma-mapping.h> #include <linux/interrupt.h> +#include <linux/debugfs.h> #include "ptdma.h" @@ -107,6 +108,7 @@ int pt_core_perform_passthru(struct pt_cmd_queue *cmd_q, cmd_q->cmd_error = 0; + cmd_q->total_pt_ops++; memset(&desc, 0, Q_DESC_SIZE); desc.dw0.val = CMD_DESC_DW0_VAL; @@ -159,6 +161,7 @@ static irqreturn_t pt_core_irq_handler(int irq, void *data) u32 status; pt_core_disable_queue_interrupts(pt); + pt->total_interrupts++; status = ioread32(cmd_q->reg_interrupt_status); if (status) { @@ -290,6 +293,9 @@ int pt_core_init(struct pt_device *pt) if (ret) goto e_dmaengine; + /* Set up debugfs entries */ + ptdma_debugfs_setup(pt); + return 0; e_dmaengine: @@ -310,6 +316,8 @@ void pt_core_destroy(struct pt_device *pt) struct pt_cmd_queue *cmd_q = &pt->cmd_q; struct pt_cmd *cmd; + ptdma_debugfs_destroy(&pt->dma_dev); + /* Unregister the DMA engine */ pt_dmaengine_unregister(pt); diff --git a/drivers/dma/ptdma/ptdma.h b/drivers/dma/ptdma/ptdma.h index 661be6b..db39a4a 100644 --- a/drivers/dma/ptdma/ptdma.h +++ b/drivers/dma/ptdma/ptdma.h @@ -239,6 +239,9 @@ struct pt_cmd_queue { u32 q_status; u32 q_int_status; u32 cmd_error; + + /* queue Statistics */ + unsigned long total_pt_ops; } ____cacheline_aligned; struct pt_device { @@ -277,6 +280,9 @@ struct pt_device { wait_queue_head_t lsb_queue; + /* Device Statistics */ + unsigned long total_interrupts; + struct pt_tasklet_data tdata; }; @@ -343,6 +349,9 @@ struct pt_dev_vdata { int pt_dmaengine_register(struct pt_device *pt); void pt_dmaengine_unregister(struct pt_device *pt); +void ptdma_debugfs_setup(struct pt_device *pt); +void ptdma_debugfs_destroy(struct dma_device *dma_dev); + int pt_core_init(struct pt_device *pt); void pt_core_destroy(struct pt_device *pt); -- 2.7.4