net/mlx5: Add devcom component for the clock shared by functions

Add new devcom component for hardware clock. When it is running in
real time mode, the functions are grouped by the identify they query.

According to firmware document, the clock identify size is 64 bits, so
it's safe to memcpy to component key, as the key size is also 64 bits.

Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c

@@ -43,6 +43,8 @@
 #include <linux/cpufeature.h>
 #endif /* CONFIG_X86 */
 
+#define MLX5_RT_CLOCK_IDENTITY_SIZE MLX5_FLD_SZ_BYTES(mrtcq_reg, rt_clock_identity)
+
 enum {
 	MLX5_PIN_MODE_IN		= 0x0,
 	MLX5_PIN_MODE_OUT		= 0x1,
@@ -77,6 +79,10 @@ enum {
 	MLX5_MTUTC_OPERATION_ADJUST_TIME_EXTENDED_MAX = 200000,
 };
 
+struct mlx5_clock_dev_state {
+	struct mlx5_devcom_comp_dev *compdev;
+};
+
 struct mlx5_clock_priv {
 	struct mlx5_clock clock;
 	struct mlx5_core_dev *mdev;
@@ -109,6 +115,22 @@ static bool mlx5_modify_mtutc_allowed(struct mlx5_core_dev *mdev)
 	return MLX5_CAP_MCAM_FEATURE(mdev, ptpcyc2realtime_modify);
 }
 
+static int mlx5_clock_identity_get(struct mlx5_core_dev *mdev,
+				   u8 identify[MLX5_RT_CLOCK_IDENTITY_SIZE])
+{
+	u32 out[MLX5_ST_SZ_DW(mrtcq_reg)] = {};
+	u32 in[MLX5_ST_SZ_DW(mrtcq_reg)] = {};
+	int err;
+
+	err = mlx5_core_access_reg(mdev, in, sizeof(in),
+				   out, sizeof(out), MLX5_REG_MRTCQ, 0, 0);
+	if (!err)
+		memcpy(identify, MLX5_ADDR_OF(mrtcq_reg, out, rt_clock_identity),
+		       MLX5_RT_CLOCK_IDENTITY_SIZE);
+
+	return err;
+}
+
 static u32 mlx5_ptp_shift_constant(u32 dev_freq_khz)
 {
 	/* Optimal shift constant leads to corrections above just 1 scaled ppm.
@@ -1231,11 +1253,26 @@ static int mlx5_clock_alloc(struct mlx5_core_dev *mdev)
 	return 0;
 }
 
+static void mlx5_shared_clock_register(struct mlx5_core_dev *mdev, u64 key)
+{
+	mdev->clock_state->compdev = mlx5_devcom_register_component(mdev->priv.devc,
+								    MLX5_DEVCOM_SHARED_CLOCK,
+								    key, NULL, mdev);
+}
+
+static void mlx5_shared_clock_unregister(struct mlx5_core_dev *mdev)
+{
+	mlx5_devcom_unregister_component(mdev->clock_state->compdev);
+}
+
 static struct mlx5_clock null_clock;
 
 int mlx5_init_clock(struct mlx5_core_dev *mdev)
 {
+	u8 identity[MLX5_RT_CLOCK_IDENTITY_SIZE];
+	struct mlx5_clock_dev_state *clock_state;
 	struct mlx5_clock *clock;
+	u64 key;
 	int err;
 
 	if (!MLX5_CAP_GEN(mdev, device_frequency_khz)) {
@@ -1244,9 +1281,26 @@ int mlx5_init_clock(struct mlx5_core_dev *mdev)
 		return 0;
 	}
 
+	clock_state = kzalloc(sizeof(*clock_state), GFP_KERNEL);
+	if (!clock_state)
+		return -ENOMEM;
+	mdev->clock_state = clock_state;
+
+	if (MLX5_CAP_MCAM_REG3(mdev, mrtcq) && mlx5_real_time_mode(mdev)) {
+		if (mlx5_clock_identity_get(mdev, identity)) {
+			mlx5_core_warn(mdev, "failed to get rt clock identity, create ptp dev per function\n");
+		} else {
+			memcpy(&key, &identity, sizeof(key));
+			mlx5_shared_clock_register(mdev, key);
+		}
+	}
+
 	err = mlx5_clock_alloc(mdev);
-	if (err)
+	if (err) {
+		kfree(clock_state);
+		mdev->clock_state = NULL;
 		return err;
+	}
 	clock = mdev->clock;
 
 	INIT_WORK(&clock->pps_info.out_work, mlx5_pps_out);
@@ -1267,4 +1321,7 @@ void mlx5_cleanup_clock(struct mlx5_core_dev *mdev)
 	cancel_work_sync(&clock->pps_info.out_work);
 
 	mlx5_clock_free(mdev);
+	mlx5_shared_clock_unregister(mdev);
+	kfree(mdev->clock_state);
+	mdev->clock_state = NULL;
 }

drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.h

@@ -11,6 +11,7 @@ enum mlx5_devcom_component {
 	MLX5_DEVCOM_MPV,
 	MLX5_DEVCOM_HCA_PORTS,
 	MLX5_DEVCOM_SD_GROUP,
+	MLX5_DEVCOM_SHARED_CLOCK,
 	MLX5_DEVCOM_NUM_COMPONENTS,
 };
 

include/linux/mlx5/driver.h

@@ -679,6 +679,7 @@ struct mlx5_rsvd_gids {
 };
 
 struct mlx5_clock;
+struct mlx5_clock_dev_state;
 struct mlx5_dm;
 struct mlx5_fw_tracer;
 struct mlx5_vxlan;
@@ -763,6 +764,7 @@ struct mlx5_core_dev {
 	struct mlx5_fpga_device *fpga;
 #endif
 	struct mlx5_clock       *clock;
+	struct mlx5_clock_dev_state *clock_state;
 	struct mlx5_ib_clock_info  *clock_info;
 	struct mlx5_fw_tracer   *tracer;
 	struct mlx5_rsc_dump    *rsc_dump;