[PATCH 5/6] drivers/misc: xdma: Add debugfs entries

From: Eddie James
Date: Mon Mar 04 2019 - 16:37:21 EST


Add debugfs entries for the relevant XDMA engine registers and for
dumping the AST2500 reserved memory space.

Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
---
drivers/misc/aspeed-xdma.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 96 insertions(+)

diff --git a/drivers/misc/aspeed-xdma.c b/drivers/misc/aspeed-xdma.c
index 0a1a093..a645a5f 100644
--- a/drivers/misc/aspeed-xdma.c
+++ b/drivers/misc/aspeed-xdma.c
@@ -142,6 +142,12 @@ struct aspeed_xdma {
struct list_head vga_blks_free;

struct miscdevice misc;
+ struct dentry *debugfs_dir;
+
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+ struct debugfs_regset32 regset;
+ struct debugfs_reg32 regs[XDMA_NUM_DEBUGFS_REGS];
+#endif /* IS_ENABLED(CONFIG_DEBUG_FS) */
};

struct aspeed_xdma_client {
@@ -634,6 +640,92 @@ static int aspeed_xdma_init_mem(struct aspeed_xdma *ctx)
return 0;
}

+#if IS_ENABLED(CONFIG_DEBUG_FS)
+static ssize_t aspeed_xdma_debugfs_vga_read(struct file *file,
+ char __user *buf, size_t len,
+ loff_t *offset)
+{
+ int rc;
+ struct inode *inode = file_inode(file);
+ struct aspeed_xdma *ctx = inode->i_private;
+ void __iomem *vga = ioremap(ctx->vga_phys, ctx->vga_size);
+ loff_t offs = *offset;
+ void *tmp;
+
+ if (!vga)
+ return -ENOMEM;
+
+ if (len + offs > ctx->vga_size) {
+ iounmap(vga);
+ return -EINVAL;
+ }
+
+ tmp = kzalloc(len, GFP_KERNEL);
+ if (!tmp) {
+ iounmap(vga);
+ return -ENOMEM;
+ }
+
+ memcpy_fromio(tmp, vga + offs, len);
+
+ rc = copy_to_user(buf, tmp, len);
+ if (rc) {
+ iounmap(vga);
+ kfree(tmp);
+ return rc;
+ }
+
+ *offset = offs + len;
+
+ kfree(tmp);
+ iounmap(vga);
+
+ return len;
+}
+
+static const struct file_operations aspeed_xdma_debugfs_vga_fops = {
+ .owner = THIS_MODULE,
+ .llseek = generic_file_llseek,
+ .read = aspeed_xdma_debugfs_vga_read,
+};
+
+static void aspeed_xdma_init_debugfs(struct aspeed_xdma *ctx)
+{
+ ctx->debugfs_dir = debugfs_create_dir(DEVICE_NAME, NULL);
+ if (IS_ERR_OR_NULL(ctx->debugfs_dir)) {
+ dev_warn(ctx->dev, "Failed to create debugfs directory.\n");
+ return;
+ }
+
+ debugfs_create_file("vga", 0444, ctx->debugfs_dir, ctx,
+ &aspeed_xdma_debugfs_vga_fops);
+
+ ctx->regs[0].name = "addr";
+ ctx->regs[0].offset = XDMA_BMC_CMD_QUEUE_ADDR;
+ ctx->regs[1].name = "endp";
+ ctx->regs[1].offset = XDMA_BMC_CMD_QUEUE_ENDP;
+ ctx->regs[2].name = "writep";
+ ctx->regs[2].offset = XDMA_BMC_CMD_QUEUE_WRITEP;
+ ctx->regs[3].name = "readp";
+ ctx->regs[3].offset = XDMA_BMC_CMD_QUEUE_READP;
+ ctx->regs[4].name = "control";
+ ctx->regs[4].offset = XDMA_CTRL;
+ ctx->regs[5].name = "status";
+ ctx->regs[5].offset = XDMA_STATUS;
+
+ ctx->regset.regs = ctx->regs;
+ ctx->regset.nregs = XDMA_NUM_DEBUGFS_REGS;
+ ctx->regset.base = ctx->base;
+
+ debugfs_create_regset32("regs", 0444, ctx->debugfs_dir, &ctx->regset);
+}
+#else
+static void aspeed_xdma_init_debugfs(struct aspeed_xdma *ctx)
+{
+}
+
+#endif /* IS_ENABLED(CONFIG_DEBUG_FS) */
+
static void aspeed_xdma_free_vga_blks(struct aspeed_xdma *ctx)
{
struct aspeed_xdma_vga_blk *free;
@@ -786,6 +878,8 @@ static int aspeed_xdma_probe(struct platform_device *pdev)
device_create_file(dev, &dev_attr_use_bmc);
device_create_file(dev, &dev_attr_use_vga);

+ aspeed_xdma_init_debugfs(ctx);
+
return 0;
}

@@ -793,6 +887,8 @@ static int aspeed_xdma_remove(struct platform_device *pdev)
{
struct aspeed_xdma *ctx = platform_get_drvdata(pdev);

+ debugfs_remove_recursive(ctx->debugfs_dir);
+
device_remove_file(ctx->dev, &dev_attr_use_vga);
device_remove_file(ctx->dev, &dev_attr_use_bmc);

--
1.8.3.1