Re: [PATCH] soc: qcom: cmd-db: Add debugfs dumping file

[Lina Iyer]

On Mon, Mar 09 2020 at 12:57 -0600, Stephen Boyd wrote:
> It's useful for kernel devs to understand what resources and data is
> stored inside command db. Add a file in debugufs called 'cmd-db' to dump
> the memory contents and strings for resources along with their
> addresses. E.g.
>
> Command DB DUMP
> Slave ARC (v16.0)
> -------------------------
> 0x00030000: cx.lvl [00 00 10 00 40 00 80 00 c0 00 00 01 80 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00]
> 0x00030004: cx.tmr
> 0x00030010: mx.lvl [00 00 10 00 00 01 80 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00]
> 0x00030014: mx.tmr
>
> Cc: Lina Iyer <ilina@xxxxxxxxxxxxxx>
> Cc: Maulik Shah <mkshah@xxxxxxxxxxxxxx>
> Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
> ---
> drivers/soc/qcom/cmd-db.c | 79 ++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 77 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c
> index f6c3d17b05c7..6c308f92a13c 100644
> --- a/drivers/soc/qcom/cmd-db.c
> +++ b/drivers/soc/qcom/cmd-db.c
> @@ -1,12 +1,13 @@
> /* SPDX-License-Identifier: GPL-2.0 */
> /* Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. */
>
> +#include <linux/debugfs.h>
> #include <linux/kernel.h>
> #include <linux/of.h>
> #include <linux/of_address.h>
> -#include <linux/of_platform.h>
> #include <linux/of_reserved_mem.h>
> #include <linux/platform_device.h>
> +#include <linux/seq_file.h>
> #include <linux/types.h>
>
> #include <soc/qcom/cmd-db.h>
> @@ -236,6 +237,78 @@ enum cmd_db_hw_type cmd_db_read_slave_id(const char *id)
> }
> EXPORT_SYMBOL(cmd_db_read_slave_id);
>
> +#ifdef CONFIG_DEBUG_FS
> +static int cmd_db_debugfs_dump(struct seq_file *seq, void *p)
> +{
> +	int i, j;
> +	const struct rsc_hdr *rsc;
> +	const struct entry_header *ent;
> +	const char *name;
> +	u16 len, version;
> +	u8 major, minor;
> +
> +	seq_puts(seq, "Command DB DUMP\n");
> +
> +	for (i = 0; i < MAX_SLV_ID; i++) {
> +
> +		rsc = &cmd_db_header->header[i];
> +		if (!rsc->slv_id)
> +			break;
> +
> +		switch (rsc->slv_id) {
> +		case CMD_DB_HW_ARC:
> +			name = "ARC";
> +			break;
> +		case CMD_DB_HW_VRM:
> +			name = "VRM";
> +			break;
> +		case CMD_DB_HW_BCM:
> +			name = "BCM";
> +			break;
> +		default:
> +			name = "Unknown";
> +			break;
> +		}
> +
> +		version = le16_to_cpu(rsc->version);
> +		major = version >> 8;
> +		minor = version;
> +
> +		seq_printf(seq, "Slave %s (v%u.%u)\n", name, major, minor);
> +		seq_puts(seq, "-------------------------\n");
> +
> +		ent = rsc_to_entry_header(rsc);
> +		for (j = 0; j < le16_to_cpu(rsc->cnt); j++, ent++) {
> +			seq_printf(seq, "0x%08x: %*pEp", le32_to_cpu(ent->addr),
0x%05x is what we would have for a resource address.
> +				   sizeof(ent->id), ent->id);
> +
> +			len = le16_to_cpu(ent->len);
> +			if (len) {
> +				seq_printf(seq, " [%*ph]",
> +					   len, rsc_offset(rsc, ent));
> +			}
> +			seq_putc(seq, '\n');
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int open_cmd_db_debugfs(struct inode *inode, struct file *file)
> +{
> +	return single_open(file, cmd_db_debugfs_dump, inode->i_private);
> +}
> +#endif
> +
> +static const struct file_operations cmd_db_debugfs_ops = {
> +#ifdef CONFIG_DEBUG_FS
> +	.open = open_cmd_db_debugfs,
> +#endif
> +	.read = seq_read,
> +	.llseek = seq_lseek,
> +	.release = single_release,
> +};
> +
> static int cmd_db_dev_probe(struct platform_device *pdev)
> {
> 	struct reserved_mem *rmem;
> @@ -259,12 +332,14 @@ static int cmd_db_dev_probe(struct platform_device *pdev)
> 		return -EINVAL;
> 	}
>
> +	debugfs_create_file("cmd-db", 0400, NULL, NULL, &cmd_db_debugfs_ops);
> +
> 	return 0;
> }
>
> static const struct of_device_id cmd_db_match_table[] = {
> 	{ .compatible = "qcom,cmd-db" },
> -	{ },
> +	{ }
> };
>
> static struct platform_driver cmd_db_dev_driver = {
>
> base-commit: 2c523b344dfa65a3738e7039832044aa133c75fb
> --
> Sent by a computer, using git, on the internet