[PATCH 03/17] drm/xe/oa/uapi: Add oa_max_sample_rate sysctl

[Ashutosh Dixit]

Introduce oa_max_sample_rate sysctl to set a max limit on the frequency of
periodic OA reports.

Signed-off-by: Ashutosh Dixit <ashutosh.dixit at intel.com>
---
 drivers/gpu/drm/xe/Makefile    |  1 +
 drivers/gpu/drm/xe/xe_device.c |  7 +++++
 drivers/gpu/drm/xe/xe_module.c |  5 ++++
 drivers/gpu/drm/xe/xe_oa.c     | 49 ++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_oa.h     | 16 +++++++++++
 5 files changed, 78 insertions(+)
 create mode 100644 drivers/gpu/drm/xe/xe_oa.c
 create mode 100644 drivers/gpu/drm/xe/xe_oa.h

diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index b719953d9d30f..cf7e0e5261f73 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -98,6 +98,7 @@ xe-y += xe_bb.o \
 	xe_mmio.o \
 	xe_mocs.o \
 	xe_module.o \
+	xe_oa.o \
 	xe_pat.o \
 	xe_pci.o \
 	xe_pcode.o \
diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index 35616d1a81a31..744d573eb2720 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -29,6 +29,7 @@
 #include "xe_irq.h"
 #include "xe_mmio.h"
 #include "xe_module.h"
+#include "xe_oa.h"
 #include "xe_pat.h"
 #include "xe_pcode.h"
 #include "xe_perf.h"
@@ -480,6 +481,10 @@ int xe_device_probe(struct xe_device *xe)
 
 	xe_heci_gsc_init(xe);
 
+	err = xe_oa_init(xe);
+	if (err)
+		goto err_irq_shutdown;
+
 	err = xe_display_init(xe);
 	if (err)
 		goto err_irq_shutdown;
@@ -526,6 +531,8 @@ void xe_device_remove(struct xe_device *xe)
 
 	xe_display_fini(xe);
 
+	xe_oa_fini(xe);
+
 	xe_heci_gsc_fini(xe);
 
 	xe_irq_shutdown(xe);
diff --git a/drivers/gpu/drm/xe/xe_module.c b/drivers/gpu/drm/xe/xe_module.c
index 8629330d928b0..176d3e6ec8464 100644
--- a/drivers/gpu/drm/xe/xe_module.c
+++ b/drivers/gpu/drm/xe/xe_module.c
@@ -10,6 +10,7 @@
 
 #include "xe_drv.h"
 #include "xe_hw_fence.h"
+#include "xe_oa.h"
 #include "xe_pci.h"
 #include "xe_perf.h"
 #include "xe_pmu.h"
@@ -76,6 +77,10 @@ static const struct init_funcs init_funcs[] = {
 		.init = xe_perf_sysctl_register,
 		.exit = xe_perf_sysctl_unregister,
 	},
+	{
+		.init = xe_oa_sysctl_register,
+		.exit = xe_oa_sysctl_unregister,
+	},
 };
 
 static int __init xe_init(void)
diff --git a/drivers/gpu/drm/xe/xe_oa.c b/drivers/gpu/drm/xe/xe_oa.c
new file mode 100644
index 0000000000000..f4cacb4af47c5
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_oa.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#include <linux/sysctl.h>
+
+#include "xe_device.h"
+#include "xe_oa.h"
+
+static int xe_oa_sample_rate_hard_limit;
+static u32 xe_oa_max_sample_rate = 100000;
+
+static struct ctl_table_header *sysctl_header;
+
+int xe_oa_init(struct xe_device *xe)
+{
+	/* Choose a representative limit */
+	xe_oa_sample_rate_hard_limit = xe_root_mmio_gt(xe)->info.reference_clock / 2;
+	return 0;
+}
+
+void xe_oa_fini(struct xe_device *xe)
+{
+}
+
+static struct ctl_table oa_ctl_table[] = {
+	{
+	 .procname = "oa_max_sample_rate",
+	 .data = &xe_oa_max_sample_rate,
+	 .maxlen = sizeof(xe_oa_max_sample_rate),
+	 .mode = 0644,
+	 .proc_handler = proc_dointvec_minmax,
+	 .extra1 = SYSCTL_ZERO,
+	 .extra2 = &xe_oa_sample_rate_hard_limit,
+	 },
+	{}
+};
+
+int xe_oa_sysctl_register(void)
+{
+	sysctl_header = register_sysctl("dev/xe", oa_ctl_table);
+	return 0;
+}
+
+void xe_oa_sysctl_unregister(void)
+{
+	unregister_sysctl_table(sysctl_header);
+}
diff --git a/drivers/gpu/drm/xe/xe_oa.h b/drivers/gpu/drm/xe/xe_oa.h
new file mode 100644
index 0000000000000..1b81330c9708b
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_oa.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#ifndef _XE_OA_H_
+#define _XE_OA_H_
+
+struct xe_device;
+
+int xe_oa_init(struct xe_device *xe);
+void xe_oa_fini(struct xe_device *xe);
+int xe_oa_sysctl_register(void);
+void xe_oa_sysctl_unregister(void);
+
+#endif
-- 
2.41.0