[PATCH v2 11/11] drm/xe: Add debugfs support for page reclamation

[Brian Nguyen <brian3.nguyen@intel.com>]

Allow for runtime modification to page reclamation feature through
debugfs configuration. This parameter will only take effect if the
platform supports the page reclamation feature by default.

v2:
 - Minor comment tweaks. (Shuicheng)
 - Convert to kstrtobool_from_user. (Michal)
 - Only expose page reclaim file if page reclaim flag
   initially supported and with that, remove
   xe_match_desc usage. (Michal)

Signed-off-by: Brian Nguyen <brian3.nguyen@intel.com>
Cc: Shuicheng Lin <shuicheng.lin@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
---
 drivers/gpu/drm/xe/xe_debugfs.c | 41 +++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_debugfs.c b/drivers/gpu/drm/xe/xe_debugfs.c
index 1d5a2a43a9d7..296b8136511b 100644
--- a/drivers/gpu/drm/xe/xe_debugfs.c
+++ b/drivers/gpu/drm/xe/xe_debugfs.c
@@ -291,6 +291,39 @@ static const struct file_operations wedged_mode_fops = {
 	.write = wedged_mode_set,
 };
 
+static ssize_t page_reclaim_hw_assist_show(struct file *f, char __user *ubuf,
+					   size_t size, loff_t *pos)
+{
+	struct xe_device *xe = file_inode(f)->i_private;
+	char buf[8];
+	int len;
+
+	len = scnprintf(buf, sizeof(buf), "%d\n", xe->info.has_page_reclaim_hw_assist);
+	return simple_read_from_buffer(ubuf, size, pos, buf, len);
+}
+
+static ssize_t page_reclaim_hw_assist_set(struct file *f, const char __user *ubuf,
+					  size_t size, loff_t *pos)
+{
+	struct xe_device *xe = file_inode(f)->i_private;
+	bool val;
+	ssize_t ret;
+
+	ret = kstrtobool_from_user(ubuf, size, &val);
+	if (ret)
+		return ret;
+
+	xe->info.has_page_reclaim_hw_assist = val;
+
+	return size;
+}
+
+static const struct file_operations page_reclaim_hw_assist_fops = {
+	.owner = THIS_MODULE,
+	.read = page_reclaim_hw_assist_show,
+	.write = page_reclaim_hw_assist_set,
+};
+
 static ssize_t atomic_svm_timeslice_ms_show(struct file *f, char __user *ubuf,
 					    size_t size, loff_t *pos)
 {
@@ -397,6 +430,14 @@ void xe_debugfs_register(struct xe_device *xe)
 	debugfs_create_file("disable_late_binding", 0600, root, xe,
 			    &disable_late_binding_fops);
 
+	/*
+	 * Don't expose page reclaim configuration file if not supported by the
+	 * hardware initially.
+	 */
+	if (xe->info.has_page_reclaim_hw_assist)
+		debugfs_create_file("page_reclaim_hw_assist", 0600, root, xe,
+				    &page_reclaim_hw_assist_fops);
+
 	for (mem_type = XE_PL_VRAM0; mem_type <= XE_PL_VRAM1; ++mem_type) {
 		man = ttm_manager_type(bdev, mem_type);
 
-- 
2.52.0