Re: [dpdk-dev] [PATCH v9 08/10] baseband/acc100: add interrupt support to PMD

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

Hi Tom, 

> From: Tom Rix <trix@redhat.com>
> On 9/28/20 5:29 PM, Nicolas Chautru wrote:
> > Adding capability and functions to support MSI interrupts, call backs
> > and inforing.
> >
> > Signed-off-by: Nicolas Chautru <nicolas.chautru@intel.com>
> > Acked-by: Liu Tianjiao <Tianjiao.liu@intel.com>
> > ---
> >  drivers/baseband/acc100/rte_acc100_pmd.c | 288
> > ++++++++++++++++++++++++++++++-
> > drivers/baseband/acc100/rte_acc100_pmd.h |  15 ++
> >  2 files changed, 300 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/baseband/acc100/rte_acc100_pmd.c
> > b/drivers/baseband/acc100/rte_acc100_pmd.c
> > index 7d4c3df..b6d9e7c 100644
> > --- a/drivers/baseband/acc100/rte_acc100_pmd.c
> > +++ b/drivers/baseband/acc100/rte_acc100_pmd.c
> > @@ -339,6 +339,213 @@
> >  	free_base_addresses(base_addrs, i);
> >  }
> >
> > +/*
> > + * Find queue_id of a device queue based on details from the Info Ring.
> > + * If a queue isn't found UINT16_MAX is returned.
> > + */
> > +static inline uint16_t
> > +get_queue_id_from_ring_info(struct rte_bbdev_data *data,
> > +		const union acc100_info_ring_data ring_data) {
> > +	uint16_t queue_id;
> > +
> > +	for (queue_id = 0; queue_id < data->num_queues; ++queue_id) {
> > +		struct acc100_queue *acc100_q =
> > +				data->queues[queue_id].queue_private;
> > +		if (acc100_q != NULL && acc100_q->aq_id == ring_data.aq_id
> &&
> > +				acc100_q->qgrp_id == ring_data.qg_id &&
> > +				acc100_q->vf_id == ring_data.vf_id)
> > +			return queue_id;
> 
> If num_queues is large, this linear search will be slow.
> 
> Consider changing the search algorithm.

This is not in the time critical part of the code


> 
> > +	}
> > +
> > +	return UINT16_MAX;
> the interrupt handlers that use this function do not a great job of handling
> this error.

if that error actualy happened then there is not much else that can be done except reporting the unexpected data.

> > +}
> > +
> > +/* Checks PF Info Ring to find the interrupt cause and handles it
> > +accordingly */ static inline void acc100_check_ir(struct
> > +acc100_device *acc100_dev) {
> > +	volatile union acc100_info_ring_data *ring_data;
> > +	uint16_t info_ring_head = acc100_dev->info_ring_head;
> > +	if (acc100_dev->info_ring == NULL)
> > +		return;
> > +
> > +	ring_data = acc100_dev->info_ring + (acc100_dev->info_ring_head &
> > +			ACC100_INFO_RING_MASK);
> > +
> > +	while (ring_data->valid) {
> > +		if ((ring_data->int_nb <
> ACC100_PF_INT_DMA_DL_DESC_IRQ) || (
> > +				ring_data->int_nb >
> > +				ACC100_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 = acc100_dev->info_ring +
> > +				(info_ring_head &
> ACC100_INFO_RING_MASK);
> These three statements are common for the ring handling, consider a macro
> or inline function.

ok

> > +	}
> > +}
> > +
> > +/* Checks PF Info Ring to find the interrupt cause and handles it
> > +accordingly */ static inline void acc100_pf_interrupt_handler(struct
> > +rte_bbdev *dev) {
> > +	struct acc100_device *acc100_dev = dev->data->dev_private;
> > +	volatile union acc100_info_ring_data *ring_data;
> > +	struct acc100_deq_intr_details deq_intr_det;
> > +
> > +	ring_data = acc100_dev->info_ring + (acc100_dev->info_ring_head &
> > +			ACC100_INFO_RING_MASK);
> > +
> > +	while (ring_data->valid) {
> > +
> > +		rte_bbdev_log_debug(
> > +				"ACC100 PF Interrupt received, Info Ring
> data: 0x%x",
> > +				ring_data->val);
> > +
> > +		switch (ring_data->int_nb) {
> > +		case ACC100_PF_INT_DMA_DL_DESC_IRQ:
> > +		case ACC100_PF_INT_DMA_UL_DESC_IRQ:
> > +		case ACC100_PF_INT_DMA_UL5G_DESC_IRQ:
> > +		case ACC100_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;
> > +		}
> > +
> > +		/* Initialize Info Ring entry and move forward */
> > +		ring_data->val = 0;
> > +		++acc100_dev->info_ring_head;
> > +		ring_data = acc100_dev->info_ring +
> > +				(acc100_dev->info_ring_head &
> > +				ACC100_INFO_RING_MASK);
> > +	}
> > +}
> > +
> > +/* Checks VF Info Ring to find the interrupt cause and handles it
> > +accordingly */ static inline void acc100_vf_interrupt_handler(struct
> > +rte_bbdev *dev)
> very similar to pf case, consider combining.
> > +{
> > +	struct acc100_device *acc100_dev = dev->data->dev_private;
> > +	volatile union acc100_info_ring_data *ring_data;
> > +	struct acc100_deq_intr_details deq_intr_det;
> > +
> > +	ring_data = acc100_dev->info_ring + (acc100_dev->info_ring_head &
> > +			ACC100_INFO_RING_MASK);
> > +
> > +	while (ring_data->valid) {
> > +
> > +		rte_bbdev_log_debug(
> > +				"ACC100 VF Interrupt received, Info Ring
> data: 0x%x",
> > +				ring_data->val);
> > +
> > +		switch (ring_data->int_nb) {
> > +		case ACC100_VF_INT_DMA_DL_DESC_IRQ:
> > +		case ACC100_VF_INT_DMA_UL_DESC_IRQ:
> > +		case ACC100_VF_INT_DMA_UL5G_DESC_IRQ:
> > +		case ACC100_VF_INT_DMA_DL5G_DESC_IRQ:
> > +			/* VFs are not aware of their vf_id - it's set to 0 in
> > +			 * queue structures.
> > +			 */
> > +			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->valid = 0;
> > +		++acc100_dev->info_ring_head;
> > +		ring_data = acc100_dev->info_ring + (acc100_dev-
> >info_ring_head
> > +				& ACC100_INFO_RING_MASK);
> > +	}
> > +}
> > +
> > +/* Interrupt handler triggered by ACC100 dev for handling specific
> > +interrupt */ static void acc100_dev_interrupt_handler(void *cb_arg) {
> > +	struct rte_bbdev *dev = cb_arg;
> > +	struct acc100_device *acc100_dev = dev->data->dev_private;
> > +
> > +	/* Read info ring */
> > +	if (acc100_dev->pf_device)
> > +		acc100_pf_interrupt_handler(dev);
> 
> combined like ..
> 
> acc100_interrupt_handler(dev, is_pf)

unsure it will help readability. Much of the code would still be distinct

> 
> > +	else
> > +		acc100_vf_interrupt_handler(dev);
> > +}
> > +
> > +/* Allocate and setup inforing */
> > +static int
> > +allocate_inforing(struct rte_bbdev *dev)
> 
> consider renaming
> 
> allocate_info_ring

ok

> 
> > +{
> > +	struct acc100_device *d = dev->data->dev_private;
> > +	const struct acc100_registry_addr *reg_addr;
> > +	rte_iova_t info_ring_phys;
> > +	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",
> > +			ACC100_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);
> The callers do not check that this fails.

arguably the error would be self contained if that did fail. But doesn't hurt to add, ok. 

> > +		return -ENOMEM;
> > +	}
> > +	info_ring_phys = rte_malloc_virt2iova(d->info_ring);
> > +
> > +	/* Setup Info Ring */
> > +	phys_high = (uint32_t)(info_ring_phys >> 32);
> > +	phys_low  = (uint32_t)(info_ring_phys);
> > +	acc100_reg_write(d, reg_addr->info_ring_hi, phys_high);
> > +	acc100_reg_write(d, reg_addr->info_ring_lo, phys_low);
> > +	acc100_reg_write(d, reg_addr->info_ring_en,
> ACC100_REG_IRQ_EN_ALL);
> > +	d->info_ring_head = (acc100_reg_read(d, reg_addr->info_ring_ptr) &
> > +			0xFFF) / sizeof(union acc100_info_ring_data);
> > +	return 0;
> > +}
> > +
> > +
> >  /* Allocate 64MB memory used for all software rings */  static int
> > acc100_setup_queues(struct rte_bbdev *dev, uint16_t num_queues, int
> > socket_id) @@ -426,6 +633,7 @@
> >  	acc100_reg_write(d, reg_addr->tail_ptrs_dl4g_hi, phys_high);
> >  	acc100_reg_write(d, reg_addr->tail_ptrs_dl4g_lo, phys_low);
> >
> > +	allocate_inforing(dev);
> need to check here
> >  	d->harq_layout = rte_zmalloc_socket("HARQ Layout",
> >  			ACC100_HARQ_LAYOUT * sizeof(*d->harq_layout),
> >  			RTE_CACHE_LINE_SIZE, dev->data->socket_id); @@ -
> 437,13 +645,53 @@
> >  	return 0;
> >  }
> >
> > +static int
> > +acc100_intr_enable(struct rte_bbdev *dev) {
> > +	int ret;
> > +	struct acc100_device *d = dev->data->dev_private;
> > +
> > +	/* Only MSI are currently supported */
> > +	if (dev->intr_handle->type == RTE_INTR_HANDLE_VFIO_MSI ||
> > +			dev->intr_handle->type == RTE_INTR_HANDLE_UIO)
> {
> > +
> > +		allocate_inforing(dev);
> need to check here
> > +
> > +		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,
> > +				acc100_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);
> does intr need to be disabled here ?

Well I don't see a lot of consistency with other drivers. Sometimes these are not even check for failure.
I would rather defer changing through other future patch if required as this is same code on other bbdev drivers already used (if changed I would rather all changed the same way). 

> > +			return ret;
> > +		}
> > +
> > +		return 0;
> > +	}
> > +
> > +	rte_bbdev_log(ERR, "ACC100 (%s) supports only VFIO MSI
> interrupts",
> > +			dev->data->name);
> > +	return -ENOTSUP;
> > +}
> > +
> >  /* Free 64MB memory used for software rings */  static int
> > acc100_dev_close(struct rte_bbdev *dev)  {
> >  	struct acc100_device *d = dev->data->dev_private;
> > +	acc100_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);
> >  		d->sw_rings_base = NULL;
> >  	}
> > @@ -643,6 +891,7 @@
> >  					RTE_BBDEV_TURBO_CRC_TYPE_24B
> |
> >
> 	RTE_BBDEV_TURBO_HALF_ITERATION_EVEN |
> >
> 	RTE_BBDEV_TURBO_EARLY_TERMINATION |
> > +
> 	RTE_BBDEV_TURBO_DEC_INTERRUPTS |
> >
> 	RTE_BBDEV_TURBO_NEG_LLR_1_BIT_IN |
> >  					RTE_BBDEV_TURBO_MAP_DEC |
> >
> 	RTE_BBDEV_TURBO_DEC_TB_CRC_24B_KEEP | @@ -663,6 +912,7
> @@
> >
> 	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, @@ -676,7 +926,8 @@
> >  				.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 =
> > @@ -701,7 +952,8 @@
> >  				RTE_BBDEV_LDPC_DECODE_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 =
> > @@ -751,14 +1003,39 @@
> >  #else
> >  	dev_info->harq_buffer_size = 0;
> >  #endif
> > +	acc100_check_ir(d);
> > +}
> > +
> > +static int
> > +acc100_queue_intr_enable(struct rte_bbdev *dev, uint16_t queue_id) {
> > +	struct acc100_queue *q = dev->data-
> >queues[queue_id].queue_private;
> > +
> > +	if (dev->intr_handle->type != RTE_INTR_HANDLE_VFIO_MSI &&
> > +			dev->intr_handle->type != RTE_INTR_HANDLE_UIO)
> > +		return -ENOTSUP;
> > +
> > +	q->irq_enable = 1;
> > +	return 0;
> > +}
> > +
> > +static int
> > +acc100_queue_intr_disable(struct rte_bbdev *dev, uint16_t queue_id) {
> > +	struct acc100_queue *q = dev->data-
> >queues[queue_id].queue_private;
> > +	q->irq_enable = 0;
> A -ENOTSUP above, should need similar check here.

How can this fail when we purely disable?

> > +	return 0;
> >  }
> >
> >  static const struct rte_bbdev_ops acc100_bbdev_ops = {
> >  	.setup_queues = acc100_setup_queues,
> > +	.intr_enable = acc100_intr_enable,
> >  	.close = acc100_dev_close,
> >  	.info_get = acc100_dev_info_get,
> >  	.queue_setup = acc100_queue_setup,
> >  	.queue_release = acc100_queue_release,
> > +	.queue_intr_enable = acc100_queue_intr_enable,
> > +	.queue_intr_disable = acc100_queue_intr_disable
> >  };
> >
> >  /* ACC100 PCI PF address map */
> > @@ -3018,8 +3295,10 @@
> >  			? (1 << RTE_BBDEV_DATA_ERROR) : 0);
> >  	op->status |= ((rsp.dma_err) ? (1 << RTE_BBDEV_DRV_ERROR) : 0);
> >  	op->status |= ((rsp.fcw_err) ? (1 << RTE_BBDEV_DRV_ERROR) : 0);
> > -	if (op->status != 0)
> > +	if (op->status != 0) {
> >  		q_data->queue_stats.dequeue_err_count++;
> > +		acc100_check_ir(q->d);
> > +	}
> >
> >  	/* CRC invalid if error exists */
> >  	if (!op->status)
> > @@ -3076,6 +3355,9 @@
> >  		op->status |= 1 << RTE_BBDEV_SYNDROME_ERROR;
> >  	op->ldpc_dec.iter_count = (uint8_t) rsp.iter_cnt;
> >
> > +	if (op->status & (1 << RTE_BBDEV_DRV_ERROR))
> > +		acc100_check_ir(q->d);
> > +
> >  	/* Check if this is the last desc in batch (Atomic Queue) */
> >  	if (desc->req.last_desc_in_batch) {
> >  		(*aq_dequeued)++;
> > diff --git a/drivers/baseband/acc100/rte_acc100_pmd.h
> > b/drivers/baseband/acc100/rte_acc100_pmd.h
> > index 78686c1..8980fa5 100644
> > --- a/drivers/baseband/acc100/rte_acc100_pmd.h
> > +++ b/drivers/baseband/acc100/rte_acc100_pmd.h
> > @@ -559,7 +559,14 @@ struct acc100_device {
> >  	/* Virtual address of the info memory routed to the this function
> under
> >  	 * operation, whether it is PF or VF.
> >  	 */
> > +	union acc100_info_ring_data *info_ring;
> 
> Need a comment that this array needs a sentinel ?

Can clarify a bit expected HW behaviour

Thanks

> 
> Tom
> 
> > +
> >  	union acc100_harq_layout_data *harq_layout;
> > +	/* Virtual Info Ring head */
> > +	uint16_t info_ring_head;
> > +	/* Number of bytes available for each queue in device, depending
> on
> > +	 * how many queues are enabled with configure()
> > +	 */
> >  	uint32_t sw_ring_size;
> >  	uint32_t ddr_size; /* Size in kB */
> >  	uint32_t *tail_ptrs; /* Base address of response tail pointer buffer
> > */ @@ -575,4 +582,12 @@ struct acc100_device {
> >  	bool configured; /**< True if this ACC100 device is configured */
> > };
> >
> > +/**
> > + * Structure with details about RTE_BBDEV_EVENT_DEQUEUE event. It's
> > +passed to
> > + * the callback function.
> > + */
> > +struct acc100_deq_intr_details {
> > +	uint16_t queue_id;
> > +};
> > +
> >  #endif /* _RTE_ACC100_PMD_H_ */