@@ -1118,6 +1118,136 @@ Figure :numref:`figure_turbo_tb_decode` above
showing the Turbo decoding of CBs using BBDEV interface in TB-mode
is also valid for LDPC decode.
+BBDEV FFT Operation
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This operation allows to run a combination of DFT and/or IDFT and/or time-domain windowing.
+These can be used in a modular fashion (using bypass modes) or as a processing pipeline
+which can be used for FFT-based baseband signal processing.
+In more details it allows :
+- to process the data first through an IDFT of adjustable size and padding;
+- to perform the windowing as a programmable cyclic shift offset of the data followed by a
+pointwise multiplication by a time domain window;
+- to process the related data through a DFT of adjustable size and depadding for each such cyclic
+shift output.
+
+A flexible number of Rx antennas are being processed in parallel with the same configuration.
+The API allows more generally for flexibility in what the PMD may support (cabability flags) and
+flexibility to adjust some of the parameters of the processing.
+
+The operation/capability flags that can be set for each FFT operation are given below.
+
+ **NOTE:** The actual operation flags that may be used with a specific
+ BBDEV PMD are dependent on the driver capabilities as reported via
+ ``rte_bbdev_info_get()``, and may be a subset of those below.
+
++--------------------------------------------------------------------+
+|Description of FFT capability flags |
++====================================================================+
+|RTE_BBDEV_FFT_WINDOWING |
+| Set to enable/support windowing in time domain |
++--------------------------------------------------------------------+
+|RTE_BBDEV_FFT_CS_ADJUSTMENT |
+| Set to enable/support the cyclic shift time offset adjustment |
++--------------------------------------------------------------------+
+|RTE_BBDEV_FFT_DFT_BYPASS |
+| Set to bypass the DFT and use directly the IDFT as an option |
++--------------------------------------------------------------------+
+|RTE_BBDEV_FFT_IDFT_BYPASS |
+| Set to bypass the IDFT and use directly the DFT as an option |
++--------------------------------------------------------------------+
+|RTE_BBDEV_FFT_WINDOWING_BYPASS |
+| Set to bypass the time domain windowing as an option |
++--------------------------------------------------------------------+
+|RTE_BBDEV_FFT_POWER_MEAS |
+| Set to provide an optional power measurement of the DFT output |
++--------------------------------------------------------------------+
+|RTE_BBDEV_FFT_FP16_INPUT |
+| Set if the input data shall use FP16 format instead of INT16 |
++--------------------------------------------------------------------+
+|RTE_BBDEV_FFT_FP16_OUTPUT |
+| Set if the output data shall use FP16 format instead of INT16 |
++--------------------------------------------------------------------+
+
+The structure passed for each FFT operation is given below,
+with the operation flags forming a bitmask in the ``op_flags`` field.
+
+.. code-block:: c
+
+ struct rte_bbdev_op_fft {
+ struct rte_bbdev_op_data base_input;
+ struct rte_bbdev_op_data base_output;
+ struct rte_bbdev_op_data power_meas_output;
+ uint32_t op_flags;
+ uint16_t input_sequence_size;
+ uint16_t input_leading_padding;
+ uint16_t output_sequence_size;
+ uint16_t output_leading_depadding;
+ uint8_t window_index[RTE_BBDEV_MAX_CS_2];
+ uint16_t cs_bitmap;
+ uint8_t num_antennas_log2;
+ uint8_t idft_log2;
+ uint8_t dft_log2;
+ int8_t cs_time_adjustment;
+ int8_t idft_shift;
+ int8_t dft_shift;
+ uint16_t ncs_reciprocal;
+ uint16_t power_shift;
+ uint16_t fp16_exp_adjust;
+ };
+
+The FFT parameters are set out in the table below.
+
++-------------------------+--------------------------------------------------------------+
+|Parameter |Description |
++=========================+==============================================================+
+|base_input |input data |
++-------------------------+--------------------------------------------------------------+
+|base_output |output data |
++-------------------------+--------------------------------------------------------------+
+|power_meas_output |optional output data with power measurement on DFT output |
++-------------------------+--------------------------------------------------------------+
+|op_flags |bitmask of all active operation capabilities |
++-------------------------+--------------------------------------------------------------+
+|input_sequence_size |size of the input sequence in 32-bits points per antenna |
++-------------------------+--------------------------------------------------------------+
+|input_leading_padding |number of points padded at the start of input data |
++-------------------------+--------------------------------------------------------------+
+|output_sequence_size |size of the output sequence per antenna and cyclic shift |
++-------------------------+--------------------------------------------------------------+
+|output_leading_depadding |number of points depadded at the start of output data |
++-------------------------+--------------------------------------------------------------+
+|window_index |optional windowing profile index used for each cyclic shift |
++-------------------------+--------------------------------------------------------------+
+|cs_bitmap |bitmap of the cyclic shift output requested (LSB for index 0) |
++-------------------------+--------------------------------------------------------------+
+|num_antennas_log2 |number of antennas as a log2 (10 maps to 1024...) |
++-------------------------+--------------------------------------------------------------+
+|idft_log2 |iDFT size as a log2 |
++-------------------------+--------------------------------------------------------------+
+|dft_log2 |DFT size as a log2 |
++-------------------------+--------------------------------------------------------------+
+|cs_time_adjustment |adjustment of time position of all the cyclic shift output |
++-------------------------+--------------------------------------------------------------+
+|idft_shift |shift down of signal level post iDFT |
++-------------------------+--------------------------------------------------------------+
+|dft_shift |shift down of signal level post DFT |
++-------------------------+--------------------------------------------------------------+
+|ncs_reciprocal |inverse of max number of CS normalized to 15b (ie. 231 for 12)|
++-------------------------+--------------------------------------------------------------+
+|power_shift |shift down of level of power measurement when enabled |
++-------------------------+--------------------------------------------------------------+
+|fp16_exp_adjust |value added to FP16 exponent at conversion from INT16 |
++-------------------------+--------------------------------------------------------------+
+
+The mbuf input ``base_input`` is mandatory for all BBDEV PMDs and is the
+incoming data for the processing. Its size may not fit into an actual mbuf, but the
+structure is used to pass iova address.
+The mbuf output ``output`` is mandatory and is output of the FFT processing chain.
+Each point is a complex number of 32bits : either as 2 INT16 or as 2 FP16 based when the option
+supported.
+The data layout is based on contiguous concatenation of output data first by cyclic shift then
+by antenna.
Sample code
-----------
@@ -24,7 +24,7 @@
#define DEV_NAME "BBDEV"
/* Number of supported operation types */
-#define BBDEV_OP_TYPE_COUNT 5
+#define BBDEV_OP_TYPE_COUNT 6
/* BBDev library logging ID */
RTE_LOG_REGISTER_DEFAULT(bbdev_logtype, NOTICE);
@@ -852,6 +852,9 @@ struct rte_bbdev *
case RTE_BBDEV_OP_LDPC_ENC:
result = sizeof(struct rte_bbdev_enc_op);
break;
+ case RTE_BBDEV_OP_FFT:
+ result = sizeof(struct rte_bbdev_fft_op);
+ break;
default:
break;
}
@@ -875,6 +878,10 @@ struct rte_bbdev *
struct rte_bbdev_enc_op *op = element;
memset(op, 0, mempool->elt_size);
op->mempool = mempool;
+ } else if (type == RTE_BBDEV_OP_FFT) {
+ struct rte_bbdev_fft_op *op = element;
+ memset(op, 0, mempool->elt_size);
+ op->mempool = mempool;
}
}
@@ -1125,6 +1132,7 @@ struct rte_mempool *
"RTE_BBDEV_OP_TURBO_ENC",
"RTE_BBDEV_OP_LDPC_DEC",
"RTE_BBDEV_OP_LDPC_ENC",
+ "RTE_BBDEV_OP_FFT",
};
if (op_type < BBDEV_OP_TYPE_COUNT)
@@ -401,6 +401,12 @@ typedef uint16_t (*rte_bbdev_enqueue_dec_ops_t)(
struct rte_bbdev_dec_op **ops,
uint16_t num);
+/** @internal Enqueue fft operations for processing on queue of a device. */
+typedef uint16_t (*rte_bbdev_enqueue_fft_ops_t)(
+ struct rte_bbdev_queue_data *q_data,
+ struct rte_bbdev_fft_op **ops,
+ uint16_t num);
+
/** @internal Dequeue encode operations from a queue of a device. */
typedef uint16_t (*rte_bbdev_dequeue_enc_ops_t)(
struct rte_bbdev_queue_data *q_data,
@@ -411,6 +417,11 @@ typedef uint16_t (*rte_bbdev_dequeue_dec_ops_t)(
struct rte_bbdev_queue_data *q_data,
struct rte_bbdev_dec_op **ops, uint16_t num);
+/** @internal Dequeue fft operations from a queue of a device. */
+typedef uint16_t (*rte_bbdev_dequeue_fft_ops_t)(
+ struct rte_bbdev_queue_data *q_data,
+ struct rte_bbdev_fft_op **ops, uint16_t num);
+
#define RTE_BBDEV_NAME_MAX_LEN 64 /**< Max length of device name */
/**
@@ -459,6 +470,10 @@ struct __rte_cache_aligned rte_bbdev {
rte_bbdev_dequeue_enc_ops_t dequeue_ldpc_enc_ops;
/** Dequeue decode function */
rte_bbdev_dequeue_dec_ops_t dequeue_ldpc_dec_ops;
+ /** Enqueue FFT function */
+ rte_bbdev_enqueue_fft_ops_t enqueue_fft_ops;
+ /** Dequeue FFT function */
+ rte_bbdev_dequeue_fft_ops_t dequeue_fft_ops;
const struct rte_bbdev_ops *dev_ops; /**< Functions exported by PMD */
struct rte_bbdev_data *data; /**< Pointer to device data */
enum rte_bbdev_state state; /**< If device is currently used or not */
@@ -591,6 +606,36 @@ struct __rte_cache_aligned rte_bbdev {
return dev->enqueue_ldpc_dec_ops(q_data, ops, num_ops);
}
+/**
+ * Enqueue a burst of fft operations to a queue of the device.
+ * This functions only enqueues as many operations as currently possible and
+ * does not block until @p num_ops entries in the queue are available.
+ * This function does not provide any error notification to avoid the
+ * corresponding overhead.
+ *
+ * @param dev_id
+ * The identifier of the device.
+ * @param queue_id
+ * The index of the queue.
+ * @param ops
+ * Pointer array containing operations to be enqueued Must have at least
+ * @p num_ops entries
+ * @param num_ops
+ * The maximum number of operations to enqueue.
+ *
+ * @return
+ * The number of operations actually enqueued (this is the number of processed
+ * entries in the @p ops array).
+ */
+__rte_experimental
+static inline uint16_t
+rte_bbdev_enqueue_fft_ops(uint16_t dev_id, uint16_t queue_id,
+ struct rte_bbdev_fft_op **ops, uint16_t num_ops)
+{
+ struct rte_bbdev *dev = &rte_bbdev_devices[dev_id];
+ struct rte_bbdev_queue_data *q_data = &dev->data->queues[queue_id];
+ return dev->enqueue_fft_ops(q_data, ops, num_ops);
+}
/**
* Dequeue a burst of processed encode operations from a queue of the device.
@@ -716,6 +761,37 @@ struct __rte_cache_aligned rte_bbdev {
return dev->dequeue_ldpc_dec_ops(q_data, ops, num_ops);
}
+/**
+ * Dequeue a burst of fft operations from a queue of the device.
+ * This functions returns only the current contents of the queue, and does not
+ * block until @ num_ops is available.
+ * This function does not provide any error notification to avoid the
+ * corresponding overhead.
+ *
+ * @param dev_id
+ * The identifier of the device.
+ * @param queue_id
+ * The index of the queue.
+ * @param ops
+ * Pointer array where operations will be dequeued to. Must have at least
+ * @p num_ops entries
+ * @param num_ops
+ * The maximum number of operations to dequeue.
+ *
+ * @return
+ * The number of operations actually dequeued (this is the number of entries
+ * copied into the @p ops array).
+ */
+__rte_experimental
+static inline uint16_t
+rte_bbdev_dequeue_fft_ops(uint16_t dev_id, uint16_t queue_id,
+ struct rte_bbdev_fft_op **ops, uint16_t num_ops)
+{
+ struct rte_bbdev *dev = &rte_bbdev_devices[dev_id];
+ struct rte_bbdev_queue_data *q_data = &dev->data->queues[queue_id];
+ return dev->dequeue_fft_ops(q_data, ops, num_ops);
+}
+
/** Definitions of device event types */
enum rte_bbdev_event_type {
RTE_BBDEV_EVENT_UNKNOWN, /**< unknown event type */
@@ -47,6 +47,8 @@
#define RTE_BBDEV_TURBO_MAX_CODE_BLOCKS (64)
/* LDPC: Maximum number of Code Blocks in Transport Block.*/
#define RTE_BBDEV_LDPC_MAX_CODE_BLOCKS (256)
+/* 12 CS maximum */
+#define RTE_BBDEV_MAX_CS_2 (6)
/** Flags for turbo decoder operation and capability structure */
enum rte_bbdev_op_td_flag_bitmasks {
@@ -211,6 +213,26 @@ enum rte_bbdev_op_ldpcenc_flag_bitmasks {
RTE_BBDEV_LDPC_ENC_CONCATENATION = (1ULL << 7)
};
+/** Flags for DFT operation and capability structure */
+enum rte_bbdev_op_fft_flag_bitmasks {
+ /** Flexible windowing capability */
+ RTE_BBDEV_FFT_WINDOWING = (1ULL << 0),
+ /** Flexible adjustment of Cyclic Shift time offset */
+ RTE_BBDEV_FFT_CS_ADJUSTMENT = (1ULL << 1),
+ /** Set for bypass the DFT and get directly into iDFT input */
+ RTE_BBDEV_FFT_DFT_BYPASS = (1ULL << 2),
+ /** Set for bypass the IDFT and get directly the DFT output */
+ RTE_BBDEV_FFT_IDFT_BYPASS = (1ULL << 3),
+ /** Set for bypass time domain windowing */
+ RTE_BBDEV_FFT_WINDOWING_BYPASS = (1ULL << 4),
+ /** Set for optional power measurement on DFT output */
+ RTE_BBDEV_FFT_POWER_MEAS = (1ULL << 5),
+ /** Set if the input data used FP16 format */
+ RTE_BBDEV_FFT_FP16_INPUT = (1ULL << 6),
+ /** Set if the output data uses FP16 format */
+ RTE_BBDEV_FFT_FP16_OUTPUT = (1ULL << 7)
+};
+
/** Flags for the Code Block/Transport block mode */
enum rte_bbdev_op_cb_mode {
/** One operation is one or fraction of one transport block */
@@ -689,6 +711,55 @@ struct rte_bbdev_op_ldpc_enc {
};
};
+/** Operation structure for FFT processing.
+ *
+ * The operation processes the data for multiple antennas in a single call
+ * (.i.e for all the REs belonging to a given SRS sequence for instance)
+ *
+ * The output mbuf data structure is expected to be allocated by the
+ * application with enough room for the output data.
+ */
+struct rte_bbdev_op_fft {
+ /** Input data starting from first antenna */
+ struct rte_bbdev_op_data base_input;
+ /** Output data starting from first antenna and first cyclic shift */
+ struct rte_bbdev_op_data base_output;
+ /** Optional power measurement output data */
+ struct rte_bbdev_op_data power_meas_output;
+ /** Flags from rte_bbdev_op_fft_flag_bitmasks */
+ uint32_t op_flags;
+ /** Input sequence size in 32-bits points */
+ uint16_t input_sequence_size;
+ /** Padding at the start of the sequence */
+ uint16_t input_leading_padding;
+ /** Output sequence size in 32-bits points */
+ uint16_t output_sequence_size;
+ /** Depadding at the start of the DFT output */
+ uint16_t output_leading_depadding;
+ /** Window index being used for each cyclic shift output */
+ uint8_t window_index[RTE_BBDEV_MAX_CS_2];
+ /** Bitmap of the cyclic shift output requested */
+ uint16_t cs_bitmap;
+ /** Number of antennas as a log2 – 8 to 128 */
+ uint8_t num_antennas_log2;
+ /** iDFT size as a log2 - 32 to 2048 */
+ uint8_t idft_log2;
+ /** DFT size as a log2 - 8 to 2048 */
+ uint8_t dft_log2;
+ /** Adjustment of position of the cyclic shifts - -31 to 31 */
+ int8_t cs_time_adjustment;
+ /** iDFT shift down */
+ int8_t idft_shift;
+ /** DFT shift down */
+ int8_t dft_shift;
+ /** NCS reciprocal factor */
+ uint16_t ncs_reciprocal;
+ /** power measurement out shift down */
+ uint16_t power_shift;
+ /** Adjust the FP6 exponent for INT<->FP16 conversion */
+ uint16_t fp16_exp_adjust;
+};
+
/** List of the capabilities for the Turbo Decoder */
struct rte_bbdev_op_cap_turbo_dec {
/** Flags from rte_bbdev_op_td_flag_bitmasks */
@@ -741,6 +812,16 @@ struct rte_bbdev_op_cap_ldpc_enc {
uint16_t num_buffers_dst;
};
+/** List of the capabilities for the FFT */
+struct rte_bbdev_op_cap_fft {
+ /** Flags from rte_bbdev_op_fft_flag_bitmasks */
+ uint32_t capability_flags;
+ /** Num input code block buffers */
+ uint16_t num_buffers_src;
+ /** Num output code block buffers */
+ uint16_t num_buffers_dst;
+};
+
/** Different operation types supported by the device */
enum rte_bbdev_op_type {
RTE_BBDEV_OP_NONE, /**< Dummy operation that does nothing */
@@ -748,6 +829,7 @@ enum rte_bbdev_op_type {
RTE_BBDEV_OP_TURBO_ENC, /**< Turbo encode */
RTE_BBDEV_OP_LDPC_DEC, /**< LDPC decode */
RTE_BBDEV_OP_LDPC_ENC, /**< LDPC encode */
+ RTE_BBDEV_OP_FFT, /**< FFT */
RTE_BBDEV_OP_TYPE_PADDED_MAX = 8, /**< Maximum op type number including padding */
};
@@ -791,6 +873,18 @@ struct rte_bbdev_dec_op {
};
};
+/** Structure specifying a single fft operation */
+struct rte_bbdev_fft_op {
+ /** Status of operation that was performed */
+ int status;
+ /** Mempool which op instance is in */
+ struct rte_mempool *mempool;
+ /** Opaque pointer for user data */
+ void *opaque_data;
+ /** Contains turbo decoder specific parameters */
+ struct rte_bbdev_op_fft fft;
+};
+
/** Operation capabilities supported by a device */
struct rte_bbdev_op_cap {
enum rte_bbdev_op_type type; /**< Type of operation */
@@ -799,6 +893,7 @@ struct rte_bbdev_op_cap {
struct rte_bbdev_op_cap_turbo_enc turbo_enc;
struct rte_bbdev_op_cap_ldpc_dec ldpc_dec;
struct rte_bbdev_op_cap_ldpc_enc ldpc_enc;
+ struct rte_bbdev_op_cap_fft fft;
} cap; /**< Operation-type specific capabilities */
};
@@ -918,6 +1013,42 @@ struct rte_mempool *
}
/**
+ * Bulk allocate fft operations from a mempool with parameter defaults reset.
+ *
+ * @param mempool
+ * Operation mempool, created by rte_bbdev_op_pool_create().
+ * @param ops
+ * Output array to place allocated operations
+ * @param num_ops
+ * Number of operations to allocate
+ *
+ * @returns
+ * - 0 on success
+ * - EINVAL if invalid mempool is provided
+ */
+__rte_experimental
+static inline int
+rte_bbdev_fft_op_alloc_bulk(struct rte_mempool *mempool,
+ struct rte_bbdev_fft_op **ops, uint16_t num_ops)
+{
+ struct rte_bbdev_op_pool_private *priv;
+ int ret;
+
+ /* Check type */
+ priv = (struct rte_bbdev_op_pool_private *)
+ rte_mempool_get_priv(mempool);
+ if (unlikely(priv->type != RTE_BBDEV_OP_FFT))
+ return -EINVAL;
+
+ /* Get elements */
+ ret = rte_mempool_get_bulk(mempool, (void **)ops, num_ops);
+ if (unlikely(ret < 0))
+ return ret;
+
+ return 0;
+}
+
+/**
* Free decode operation structures that were allocated by
* rte_bbdev_dec_op_alloc_bulk().
* All structures must belong to the same mempool.
@@ -951,6 +1082,24 @@ struct rte_mempool *
rte_mempool_put_bulk(ops[0]->mempool, (void **)ops, num_ops);
}
+/**
+ * Free encode operation structures that were allocated by
+ * rte_bbdev_fft_op_alloc_bulk().
+ * All structures must belong to the same mempool.
+ *
+ * @param ops
+ * Operation structures
+ * @param num_ops
+ * Number of structures
+ */
+__rte_experimental
+static inline void
+rte_bbdev_fft_op_free_bulk(struct rte_bbdev_fft_op **ops, unsigned int num_ops)
+{
+ if (num_ops > 0)
+ rte_mempool_put_bulk(ops[0]->mempool, (void **)ops, num_ops);
+}
+
#ifdef __cplusplus
}
#endif
@@ -44,4 +44,8 @@ EXPERIMENTAL {
global:
rte_bbdev_device_status_str;
+ rte_bbdev_enqueue_fft_ops;
+ rte_bbdev_dequeue_fft_ops;
+ rte_bbdev_fft_op_alloc_bulk;
+ rte_bbdev_fft_op_free_bulk;
};