perf: arm_cspmu: Separate Arm and vendor module

Arm Coresight PMU driver consists of main standard code and
vendor backend code. Both are currently built as a single module.
This patch adds vendor registration API to separate the two to
keep things modular. The main driver requests each known backend
module during initialization and defer device binding process.
The backend module then registers an init callback to the main
driver and continue the device driver binding process.

Signed-off-by: Besar Wicaksono <bwicaksono@nvidia.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-and-tested-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Link: https://lore.kernel.org/r/20230821231608.50911-1-bwicaksono@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 30 insertions, 4 deletions

diff --git a/drivers/perf/arm_cspmu/nvidia_cspmu.c b/drivers/perf/arm_cspmu/nvidia_cspmu.c
index 72ef80caa3c8..0382b702f092 100644
--- a/drivers/perf/arm_cspmu/nvidia_cspmu.c
+++ b/drivers/perf/arm_cspmu/nvidia_cspmu.c
@@ -1,14 +1,15 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
  *
  */
 
 /* Support for NVIDIA specific attributes. */
 
+#include <linux/module.h>
 #include <linux/topology.h>
 
-#include "nvidia_cspmu.h"
+#include "arm_cspmu.h"
 
 #define NV_PCIE_PORT_COUNT           10ULL
 #define NV_PCIE_FILTER_ID_MASK       GENMASK_ULL(NV_PCIE_PORT_COUNT - 1, 0)
@@ -351,7 +352,7 @@ static char *nv_cspmu_format_name(const struct arm_cspmu *cspmu,
 	return name;
 }
 
-int nv_cspmu_init_ops(struct arm_cspmu *cspmu)
+static int nv_cspmu_init_ops(struct arm_cspmu *cspmu)
 {
 	u32 prodid;
 	struct nv_cspmu_ctx *ctx;
@@ -395,6 +396,31 @@ int nv_cspmu_init_ops(struct arm_cspmu *cspmu)
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(nv_cspmu_init_ops);
+
+/* Match all NVIDIA Coresight PMU devices */
+static const struct arm_cspmu_impl_match nv_cspmu_param = {
+	.pmiidr_val	= ARM_CSPMU_IMPL_ID_NVIDIA,
+	.module		= THIS_MODULE,
+	.impl_init_ops	= nv_cspmu_init_ops
+};
+
+static int __init nvidia_cspmu_init(void)
+{
+	int ret;
+
+	ret = arm_cspmu_impl_register(&nv_cspmu_param);
+	if (ret)
+		pr_err("nvidia_cspmu backend registration error: %d\n", ret);
+
+	return ret;
+}
+
+static void __exit nvidia_cspmu_exit(void)
+{
+	arm_cspmu_impl_unregister(&nv_cspmu_param);
+}
+
+module_init(nvidia_cspmu_init);
+module_exit(nvidia_cspmu_exit);
 
 MODULE_LICENSE("GPL v2");