Commit 143a2584 authored by Athira Rajeev's avatar Athira Rajeev Committed by Madhavan Srinivasan
Browse files

powerpc/pseries/htmdump: Add htm capabilities support to htmdump module 



Support dumping HTM capabilities information from Hardware
Trace Macro (HTM) function via debugfs interface. Under
debugfs folder "/sys/kernel/debug/powerpc/htmdump", add
file "htmcaps".

The interface allows only read of this file which will present the
content of HTM buffer from the hcall.

Signed-off-by: default avatarAthira Rajeev <atrajeev@linux.ibm.com>
Tested-by: default avatarVenkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: default avatarMadhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250420180844.53128-9-atrajeev@linux.ibm.com
parent d3f24bf2

arch/powerpc/platforms/pseries/htmdump.c

+40 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
static void *htm_buf;

static void *htm_status_buf;

static void *htm_info_buf;

static void *htm_caps_buf;

static u32 nodeindex;

static u32 nodalchipindex;

static u32 coreindexonchip;
@@ -304,12 +305,43 @@ static ssize_t htminfo_read(struct file *filp, char __user *ubuf, 
	return simple_read_from_buffer(ubuf, count, ppos, htm_info_buf, to_copy);

}



static ssize_t htmcaps_read(struct file *filp, char __user *ubuf,

			     size_t count, loff_t *ppos)

{

	void *htm_caps_buf = filp->private_data;

	long rc, ret;



	/*

	 * Invoke H_HTM call with:

	 * - operation as htm capabilities (H_HTM_OP_CAPABILITIES)

	 * - last three values as addr, size (0x80 for Capabilities Output Buffer

	 *   and zero

	 */

	rc = htm_hcall_wrapper(htmflags, nodeindex, nodalchipindex, coreindexonchip,

				   htmtype, H_HTM_OP_CAPABILITIES, virt_to_phys(htm_caps_buf),

				   0x80, 0);



	ret = htm_return_check(rc);

	if (ret <= 0) {

		pr_debug("H_HTM hcall failed for op: H_HTM_OP_CAPABILITIES, returning %ld\n", ret);

		return ret;

	}



	return simple_read_from_buffer(ubuf, count, ppos, htm_caps_buf, 0x80);

}



static const struct file_operations htminfo_fops = {

	.llseek = NULL,

	.read   = htminfo_read,

	.open   = simple_open,

};



static const struct file_operations htmcaps_fops = {

	.llseek = NULL,

	.read   = htmcaps_read,

	.open   = simple_open,

};



static int  htmsetup_set(void *data, u64 val)

{

	long rc, ret;
@@ -417,8 +449,16 @@ static int htmdump_init_debugfs(void) 
		return -ENOMEM;

	}



	/* Debugfs interface file to present HTM capabilities */

	htm_caps_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);

	if (!htm_caps_buf) {

		pr_err("Failed to allocate htm caps buf\n");

		return -ENOMEM;

	}



	debugfs_create_file("htmstatus", 0400, htmdump_debugfs_dir, htm_status_buf, &htmstatus_fops);

	debugfs_create_file("htminfo", 0400, htmdump_debugfs_dir, htm_info_buf, &htminfo_fops);

	debugfs_create_file("htmcaps", 0400, htmdump_debugfs_dir, htm_caps_buf, &htmcaps_fops);



	return 0;

}