RE: [PATCH v6 11/14] baseband/acc: support interrupt

["Chautru, Nicolas" <nicolas.chautru@intel.com>]

Hi Maxime, 

> -----Original Message-----
> From: Maxime Coquelin <maxime.coquelin@redhat.com>
> Sent: Tuesday, September 27, 2022 6:50 AM
> To: Chautru, Nicolas <nicolas.chautru@intel.com>; dev@dpdk.org;
> thomas@monjalon.net
> Cc: trix@redhat.com; mdr@ashroe.eu; Richardson, Bruce
> <bruce.richardson@intel.com>; hemant.agrawal@nxp.com;
> david.marchand@redhat.com; stephen@networkplumber.org; Vargas, Hernan
> <hernan.vargas@intel.com>
> Subject: Re: [PATCH v6 11/14] baseband/acc: support interrupt
> 
> 
> 
> On 9/24/22 02:50, Nicolas Chautru wrote:
> > From: Nic Chautru <nicolas.chautru@intel.com>
> >
> > Adding support for capability and functions for MSI/MSI-X interrupt
> > and underlying information ring.
> >
> > Signed-off-by: Nic Chautru <nicolas.chautru@intel.com>
> > ---
> >   drivers/baseband/acc/rte_acc200_pmd.c | 303
> +++++++++++++++++++++++++-
> >   1 file changed, 301 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/baseband/acc/rte_acc200_pmd.c
> > b/drivers/baseband/acc/rte_acc200_pmd.c
> > index 7f2cd71166..46027ff6af 100644
> > --- a/drivers/baseband/acc/rte_acc200_pmd.c
> > +++ b/drivers/baseband/acc/rte_acc200_pmd.c
> > @@ -220,6 +220,152 @@ fetch_acc200_config(struct rte_bbdev *dev)
> >   			acc_conf->q_fft.aq_depth_log2);
> >   }
> >
> > +/* Checks PF Info Ring to find the interrupt cause and handles it
> > +accordingly */ static inline void acc200_check_ir(struct acc_device
> > +*acc200_dev) {
> > +	volatile union acc_info_ring_data *ring_data;
> > +	uint16_t info_ring_head = acc200_dev->info_ring_head;
> > +	if (acc200_dev->info_ring == NULL)
> > +		return;
> 
> My understanding is this function is called in the hot path, and above condition
> is not expected to be true in working conditions.
> If so, it can be marked as unlikely.

Thanks, updated in v7

> 
> > +
> > +	ring_data = acc200_dev->info_ring + (acc200_dev->info_ring_head &
> > +			ACC_INFO_RING_MASK);
> > +
> > +	while (ring_data->valid) {
> > +		if ((ring_data->int_nb < ACC200_PF_INT_DMA_DL_DESC_IRQ)
> || (
> > +				ring_data->int_nb >
> > +				ACC200_PF_INT_DMA_DL5G_DESC_IRQ)) {
> > +			rte_bbdev_log(WARNING, "InfoRing: ITR:%d
> Info:0x%x",
> > +				ring_data->int_nb, ring_data->detailed_info);
> > +			/* Initialize Info Ring entry and move forward */
> > +			ring_data->val = 0;
> > +		}
> > +		info_ring_head++;
> > +		ring_data = acc200_dev->info_ring +
> > +				(info_ring_head & ACC_INFO_RING_MASK);
> > +	}
> > +}
> > +
> > +/* Interrupt handler triggered by ACC200 dev for handling specific
> > +interrupt */ static void acc200_dev_interrupt_handler(void *cb_arg) {
> > +	struct rte_bbdev *dev = cb_arg;
> > +	struct acc_device *acc200_dev = dev->data->dev_private;
> > +	volatile union acc_info_ring_data *ring_data;
> > +	struct acc_deq_intr_details deq_intr_det;
> > +
> > +	ring_data = acc200_dev->info_ring + (acc200_dev->info_ring_head &
> > +ACC_INFO_RING_MASK);
> > +
> > +	while (ring_data->valid) {
> > +		if (acc200_dev->pf_device) {
> > +			rte_bbdev_log_debug(
> > +					"ACC200 PF Interrupt received, Info
> Ring data: 0x%x -> %d",
> > +					ring_data->val, ring_data->int_nb);
> > +
> > +			switch (ring_data->int_nb) {
> > +			case ACC200_PF_INT_DMA_DL_DESC_IRQ:
> > +			case ACC200_PF_INT_DMA_UL_DESC_IRQ:
> > +			case ACC200_PF_INT_DMA_FFT_DESC_IRQ:
> > +			case ACC200_PF_INT_DMA_UL5G_DESC_IRQ:
> > +			case ACC200_PF_INT_DMA_DL5G_DESC_IRQ:
> > +				deq_intr_det.queue_id =
> get_queue_id_from_ring_info(
> > +						dev->data, *ring_data);
> > +				if (deq_intr_det.queue_id == UINT16_MAX) {
> > +					rte_bbdev_log(ERR,
> > +							"Couldn't find queue:
> aq_id: %u, qg_id: %u, vf_id: %u",
> > +							ring_data->aq_id,
> > +							ring_data->qg_id,
> > +							ring_data->vf_id);
> > +					return;
> > +				}
> > +				rte_bbdev_pmd_callback_process(dev,
> > +
> 	RTE_BBDEV_EVENT_DEQUEUE, &deq_intr_det);
> > +				break;
> > +			default:
> > +				rte_bbdev_pmd_callback_process(dev,
> RTE_BBDEV_EVENT_ERROR, NULL);
> > +				break;
> > +			}
> > +		} else {
> > +			rte_bbdev_log_debug(
> > +					"ACC200 VF Interrupt received, Info
> Ring data: 0x%x\n",
> > +					ring_data->val);
> > +			switch (ring_data->int_nb) {
> > +			case ACC200_VF_INT_DMA_DL_DESC_IRQ:
> > +			case ACC200_VF_INT_DMA_UL_DESC_IRQ:
> > +			case ACC200_VF_INT_DMA_FFT_DESC_IRQ:
> > +			case ACC200_VF_INT_DMA_UL5G_DESC_IRQ:
> > +			case ACC200_VF_INT_DMA_DL5G_DESC_IRQ:
> > +				/* VFs are not aware of their vf_id - it's set to
> 0  */
> > +				ring_data->vf_id = 0;
> > +				deq_intr_det.queue_id =
> get_queue_id_from_ring_info(
> > +						dev->data, *ring_data);
> > +				if (deq_intr_det.queue_id == UINT16_MAX) {
> > +					rte_bbdev_log(ERR,
> > +							"Couldn't find queue:
> aq_id: %u, qg_id: %u",
> > +							ring_data->aq_id,
> > +							ring_data->qg_id);
> > +					return;
> > +				}
> > +				rte_bbdev_pmd_callback_process(dev,
> > +
> 	RTE_BBDEV_EVENT_DEQUEUE, &deq_intr_det);
> > +				break;
> > +			default:
> > +				rte_bbdev_pmd_callback_process(dev,
> RTE_BBDEV_EVENT_ERROR, NULL);
> > +				break;
> > +			}
> > +		}
> > +
> > +		/* Initialize Info Ring entry and move forward */
> > +		ring_data->val = 0;
> > +		++acc200_dev->info_ring_head;
> > +		ring_data = acc200_dev->info_ring +
> > +				(acc200_dev->info_ring_head &
> ACC_INFO_RING_MASK);
> > +	}
> > +}
> > +
> > +/* Allocate and setup inforing */
> > +static int
> > +allocate_info_ring(struct rte_bbdev *dev) {
> > +	struct acc_device *d = dev->data->dev_private;
> > +	const struct acc200_registry_addr *reg_addr;
> > +	rte_iova_t info_ring_iova;
> > +	uint32_t phys_low, phys_high;
> > +
> > +	if (d->info_ring != NULL)
> > +		return 0; /* Already configured */
> > +
> > +	/* Choose correct registry addresses for the device type */
> > +	if (d->pf_device)
> > +		reg_addr = &pf_reg_addr;
> > +	else
> > +		reg_addr = &vf_reg_addr;
> > +	/* Allocate InfoRing */
> > +	d->info_ring = rte_zmalloc_socket("Info Ring",
> ACC_INFO_RING_NUM_ENTRIES *
> > +			sizeof(*d->info_ring), RTE_CACHE_LINE_SIZE, dev-
> >data->socket_id);
> > +	if (d->info_ring == NULL) {
> > +		rte_bbdev_log(ERR,
> > +				"Failed to allocate Info Ring for %s:%u",
> > +				dev->device->driver->name,
> > +				dev->data->dev_id);
> > +		return -ENOMEM;
> > +	}
> > +	info_ring_iova = rte_malloc_virt2iova(d->info_ring);
> > +
> > +	/* Setup Info Ring */
> > +	phys_high = (uint32_t)(info_ring_iova >> 32);
> > +	phys_low  = (uint32_t)(info_ring_iova);
> > +	acc_reg_write(d, reg_addr->info_ring_hi, phys_high);
> > +	acc_reg_write(d, reg_addr->info_ring_lo, phys_low);
> > +	acc_reg_write(d, reg_addr->info_ring_en, ACC200_REG_IRQ_EN_ALL);
> > +	d->info_ring_head = (acc_reg_read(d, reg_addr->info_ring_ptr) &
> > +			0xFFF) / sizeof(union acc_info_ring_data);
> > +	return 0;
> > +}
> > +
> > +
> >   /* Allocate 64MB memory used for all software rings */
> >   static int
> >   acc200_setup_queues(struct rte_bbdev *dev, uint16_t num_queues, int
> > socket_id) @@ -328,6 +474,14 @@ acc200_setup_queues(struct rte_bbdev
> *dev, uint16_t num_queues, int socket_id)
> >   	acc_reg_write(d, reg_addr->tail_ptrs_fft_hi, phys_high);
> >   	acc_reg_write(d, reg_addr->tail_ptrs_fft_lo, phys_low);
> >
> > +	ret = allocate_info_ring(dev);
> > +	if (ret < 0) {
> > +		rte_bbdev_log(ERR, "Failed to allocate info_ring for %s:%u",
> > +				dev->device->driver->name,
> > +				dev->data->dev_id);
> > +		/* Continue */
> > +	}
> > +
> >   	if (d->harq_layout == NULL)
> >   		d->harq_layout = rte_zmalloc_socket("HARQ Layout",
> >   				ACC_HARQ_LAYOUT * sizeof(*d-
> >harq_layout), @@ -358,17 +512,120
> > @@ acc200_setup_queues(struct rte_bbdev *dev, uint16_t num_queues, int
> socket_id)
> >   	return ret;
> >   }
> >
> > +static int
> > +acc200_intr_enable(struct rte_bbdev *dev) {
> > +	int ret;
> > +	struct acc_device *d = dev->data->dev_private;
> > +	/*
> > +	 * MSI/MSI-X are supported
> > +	 * Option controlled by vfio-intr through EAL parameter
> > +	 */
> > +	if (rte_intr_type_get(dev->intr_handle) ==
> RTE_INTR_HANDLE_VFIO_MSI)
> > +{
> > +
> > +		ret = allocate_info_ring(dev);
> > +		if (ret < 0) {
> > +			rte_bbdev_log(ERR,
> > +					"Couldn't allocate info ring for device:
> %s",
> > +					dev->data->name);
> > +			return ret;
> > +		}
> > +		ret = rte_intr_enable(dev->intr_handle);
> > +		if (ret < 0) {
> > +			rte_bbdev_log(ERR,
> > +					"Couldn't enable interrupts for device:
> %s",
> > +					dev->data->name);
> > +			rte_free(d->info_ring);
> > +			return ret;
> > +		}
> > +		ret = rte_intr_callback_register(dev->intr_handle,
> > +				acc200_dev_interrupt_handler, dev);
> > +		if (ret < 0) {
> > +			rte_bbdev_log(ERR,
> > +					"Couldn't register interrupt callback
> for device: %s",
> > +					dev->data->name);
> > +			rte_free(d->info_ring);
> > +			return ret;
> > +		}
> > +
> > +		return 0;
> > +	} else if (rte_intr_type_get(dev->intr_handle) ==
> RTE_INTR_HANDLE_VFIO_MSIX) {
> > +		int i, max_queues;
> > +		struct acc_device *acc200_dev = dev->data->dev_private;
> > +
> > +		ret = allocate_info_ring(dev);
> > +		if (ret < 0) {
> > +			rte_bbdev_log(ERR,
> > +					"Couldn't allocate info ring for device:
> %s",
> > +					dev->data->name);
> > +			return ret;
> > +		}
> > +
> > +		if (acc200_dev->pf_device)
> > +			max_queues = ACC200_MAX_PF_MSIX;
> > +		else
> > +			max_queues = ACC200_MAX_VF_MSIX;
> > +
> > +		if (rte_intr_efd_enable(dev->intr_handle, max_queues)) {
> > +			rte_bbdev_log(ERR, "Failed to create fds for %u
> queues",
> > +					dev->data->num_queues);
> > +			return -1;
> > +		}
> > +
> > +		for (i = 0; i < max_queues; ++i) {
> > +			if (rte_intr_efds_index_set(dev->intr_handle, i,
> > +					rte_intr_fd_get(dev->intr_handle)))
> > +				return -rte_errno;
> > +		}
> > +
> > +		if (rte_intr_vec_list_alloc(dev->intr_handle, "intr_vec",
> > +				dev->data->num_queues)) {
> > +			rte_bbdev_log(ERR, "Failed to allocate %u vectors",
> > +					dev->data->num_queues);
> > +			return -ENOMEM;
> > +		}
> > +
> > +		ret = rte_intr_enable(dev->intr_handle);
> > +
> > +		if (ret < 0) {
> > +			rte_bbdev_log(ERR,
> > +					"Couldn't enable interrupts for device:
> %s",
> > +					dev->data->name);
> > +			rte_free(d->info_ring);
> > +			return ret;
> > +		}
> > +		ret = rte_intr_callback_register(dev->intr_handle,
> > +				acc200_dev_interrupt_handler, dev);
> > +		if (ret < 0) {
> > +			rte_bbdev_log(ERR,
> > +					"Couldn't register interrupt callback
> for device: %s",
> > +					dev->data->name);
> > +			rte_free(d->info_ring);
> > +			return ret;
> > +		}
> > +
> > +		return 0;
> > +	}
> > +
> > +	rte_bbdev_log(ERR, "ACC200 (%s) supports only VFIO MSI/MSI-X
> interrupts\n",
> > +			dev->data->name);
> > +	return -ENOTSUP;
> > +}
> > +
> >   /* Free memory used for software rings */
> >   static int
> >   acc200_dev_close(struct rte_bbdev *dev)
> >   {
> >   	struct acc_device *d = dev->data->dev_private;
> > +	acc200_check_ir(d);
> >   	if (d->sw_rings_base != NULL) {
> >   		rte_free(d->tail_ptrs);
> > +		rte_free(d->info_ring);
> >   		rte_free(d->sw_rings_base);
> >   		rte_free(d->harq_layout);
> >   		d->sw_rings_base = NULL;
> >   		d->tail_ptrs = NULL;
> > +		d->info_ring = NULL;
> >   		d->harq_layout = NULL;
> 
> Not a big deal, but rte_free() and NULL assignment are not done in the same
> order.

Thanks, updated in v7

> 
> >   	}
> >   	/* Ensure all in flight HW transactions are completed */ @@ -670,6
> > +927,7 @@ acc200_dev_info_get(struct rte_bbdev *dev,
> >
> 	RTE_BBDEV_TURBO_CONTINUE_CRC_MATCH |
> >   					RTE_BBDEV_TURBO_SOFT_OUTPUT |
> >
> 	RTE_BBDEV_TURBO_EARLY_TERMINATION |
> > +
> 	RTE_BBDEV_TURBO_DEC_INTERRUPTS |
> >
> 	RTE_BBDEV_TURBO_NEG_LLR_1_BIT_IN |
> >
> 	RTE_BBDEV_TURBO_NEG_LLR_1_BIT_SOFT_OUT |
> >   					RTE_BBDEV_TURBO_MAP_DEC |
> > @@ -691,6 +949,7 @@ acc200_dev_info_get(struct rte_bbdev *dev,
> >
> 	RTE_BBDEV_TURBO_CRC_24B_ATTACH |
> >
> 	RTE_BBDEV_TURBO_RV_INDEX_BYPASS |
> >   					RTE_BBDEV_TURBO_RATE_MATCH |
> > +
> 	RTE_BBDEV_TURBO_ENC_INTERRUPTS |
> >
> 	RTE_BBDEV_TURBO_ENC_SCATTER_GATHER,
> >   				.num_buffers_src =
> >
> 	RTE_BBDEV_TURBO_MAX_CODE_BLOCKS, @@ -704,7 +963,8 @@
> > acc200_dev_info_get(struct rte_bbdev *dev,
> >   				.capability_flags =
> >   					RTE_BBDEV_LDPC_RATE_MATCH |
> >   					RTE_BBDEV_LDPC_CRC_24B_ATTACH
> |
> > -
> 	RTE_BBDEV_LDPC_INTERLEAVER_BYPASS,
> > +
> 	RTE_BBDEV_LDPC_INTERLEAVER_BYPASS |
> > +					RTE_BBDEV_LDPC_ENC_INTERRUPTS,
> >   				.num_buffers_src =
> >
> 	RTE_BBDEV_LDPC_MAX_CODE_BLOCKS,
> >   				.num_buffers_dst =
> > @@ -725,7 +985,8 @@ acc200_dev_info_get(struct rte_bbdev *dev,
> >   				RTE_BBDEV_LDPC_DEINTERLEAVER_BYPASS |
> >   				RTE_BBDEV_LDPC_DEC_SCATTER_GATHER |
> >   				RTE_BBDEV_LDPC_HARQ_6BIT_COMPRESSION
> |
> > -				RTE_BBDEV_LDPC_LLR_COMPRESSION,
> > +				RTE_BBDEV_LDPC_LLR_COMPRESSION |
> > +				RTE_BBDEV_LDPC_DEC_INTERRUPTS,
> >   			.llr_size = 8,
> >   			.llr_decimals = 1,
> >   			.num_buffers_src =
> > @@ -793,15 +1054,46 @@ acc200_dev_info_get(struct rte_bbdev *dev,
> >   	dev_info->min_alignment = 1;
> >   	dev_info->capabilities = bbdev_capabilities;
> >   	dev_info->harq_buffer_size = 0;
> > +
> > +	acc200_check_ir(d);
> > +}
> > +
> > +static int
> > +acc200_queue_intr_enable(struct rte_bbdev *dev, uint16_t queue_id) {
> > +	struct acc_queue *q = dev->data->queues[queue_id].queue_private;
> > +
> > +	if (rte_intr_type_get(dev->intr_handle) !=
> RTE_INTR_HANDLE_VFIO_MSI &&
> > +			rte_intr_type_get(dev->intr_handle) !=
> RTE_INTR_HANDLE_VFIO_MSIX)
> > +		return -ENOTSUP;
> > +
> > +	q->irq_enable = 1;
> > +	return 0;
> > +}
> > +
> > +static int
> > +acc200_queue_intr_disable(struct rte_bbdev *dev, uint16_t queue_id) {
> > +	struct acc_queue *q = dev->data->queues[queue_id].queue_private;
> > +
> > +	if (rte_intr_type_get(dev->intr_handle) !=
> RTE_INTR_HANDLE_VFIO_MSI &&
> > +			rte_intr_type_get(dev->intr_handle) !=
> RTE_INTR_HANDLE_VFIO_MSIX)
> > +		return -ENOTSUP;
> > +
> > +	q->irq_enable = 0;
> > +	return 0;
> >   }
> >
> >   static const struct rte_bbdev_ops acc200_bbdev_ops = {
> >   	.setup_queues = acc200_setup_queues,
> > +	.intr_enable = acc200_intr_enable,
> >   	.close = acc200_dev_close,
> >   	.info_get = acc200_dev_info_get,
> >   	.queue_setup = acc200_queue_setup,
> >   	.queue_release = acc200_queue_release,
> >   	.queue_stop = acc_queue_stop,
> > +	.queue_intr_enable = acc200_queue_intr_enable,
> > +	.queue_intr_disable = acc200_queue_intr_disable
> >   };
> >
> >   /* ACC200 PCI PF address map */
> > @@ -2574,6 +2866,7 @@ dequeue_dec_one_op_cb(struct
> rte_bbdev_queue_data *q_data,
> >   	if (op->status != 0) {
> >   		/* These errors are not expected */
> >   		q_data->queue_stats.dequeue_err_count++;
> > +		acc200_check_ir(q->d);
> >   	}
> >
> >   	/* CRC invalid if error exists */
> > @@ -2643,6 +2936,9 @@ dequeue_ldpc_dec_one_op_cb(struct
> > rte_bbdev_queue_data *q_data,
> >
> >   	op->ldpc_dec.iter_count = (uint8_t) rsp.iter_cnt;
> >
> > +	if (op->status & (1 << RTE_BBDEV_DRV_ERROR))
> > +		acc200_check_ir(q->d);
> > +
> >   	/* Check if this is the last desc in batch (Atomic Queue) */
> >   	if (desc->req.last_desc_in_batch) {
> >   		(*aq_dequeued)++;
> > @@ -3098,6 +3394,9 @@ dequeue_fft_one_op(struct
> rte_bbdev_queue_data *q_data,
> >   	if (op->status != 0)
> >   		q_data->queue_stats.dequeue_err_count++;
> >
> > +	if (op->status & (1 << RTE_BBDEV_DRV_ERROR))
> > +		acc200_check_ir(q->d);
> > +
> >   	/* Check if this is the last desc in batch (Atomic Queue) */
> >   	if (desc->req.last_desc_in_batch) {
> >   		(*aq_dequeued)++;