From: longli@linuxonhyperv.com
To: Ferruh Yigit <ferruh.yigit@xilinx.com>
Cc: dev@dpdk.org, Ajay Sharma <sharmaajay@microsoft.com>,
Stephen Hemminger <sthemmin@microsoft.com>,
Long Li <longli@microsoft.com>
Subject: [Patch v2 11/17] net/mana: implement the hardware layer operations
Date: Tue, 5 Jul 2022 17:28:42 -0700 [thread overview]
Message-ID: <1657067328-18374-12-git-send-email-longli@linuxonhyperv.com> (raw)
In-Reply-To: <1657067328-18374-1-git-send-email-longli@linuxonhyperv.com>
From: Long Li <longli@microsoft.com>
The hardware layer of MANA understands the device queue and doorbell
formats. Those functions are implemented for use by packet RX/TX code.
Signed-off-by: Long Li <longli@microsoft.com>
---
Change log:
v2:
Remove unused header files.
Rename a camel case.
drivers/net/mana/gdma.c | 284 +++++++++++++++++++++++++++++++++++
drivers/net/mana/mana.h | 183 ++++++++++++++++++++++
drivers/net/mana/meson.build | 1 +
3 files changed, 468 insertions(+)
create mode 100644 drivers/net/mana/gdma.c
diff --git a/drivers/net/mana/gdma.c b/drivers/net/mana/gdma.c
new file mode 100644
index 0000000000..077ac7744b
--- /dev/null
+++ b/drivers/net/mana/gdma.c
@@ -0,0 +1,284 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2022 Microsoft Corporation
+ */
+
+#include <ethdev_driver.h>
+#include <rte_io.h>
+
+#include "mana.h"
+
+uint8_t *gdma_get_wqe_pointer(struct mana_gdma_queue *queue)
+{
+ uint32_t offset_in_bytes =
+ (queue->head * GDMA_WQE_ALIGNMENT_UNIT_SIZE) &
+ (queue->size - 1);
+
+ DRV_LOG(DEBUG, "txq sq_head %u sq_size %u offset_in_bytes %u",
+ queue->head, queue->size, offset_in_bytes);
+
+ if (offset_in_bytes + GDMA_WQE_ALIGNMENT_UNIT_SIZE > queue->size)
+ DRV_LOG(ERR, "fatal error: offset_in_bytes %u too big",
+ offset_in_bytes);
+
+ return ((uint8_t *)queue->buffer) + offset_in_bytes;
+}
+
+static uint32_t
+write_dma_client_oob(uint8_t *work_queue_buffer_pointer,
+ const struct gdma_work_request *work_request,
+ uint32_t client_oob_size)
+{
+ uint8_t *p = work_queue_buffer_pointer;
+
+ struct gdma_wqe_dma_oob *header = (struct gdma_wqe_dma_oob *)p;
+
+ memset(header, 0, sizeof(struct gdma_wqe_dma_oob));
+ header->num_sgl_entries = work_request->num_sgl_elements;
+ header->inline_client_oob_size_in_dwords =
+ client_oob_size / sizeof(uint32_t);
+ header->client_data_unit = work_request->client_data_unit;
+
+ DRV_LOG(DEBUG, "queue buf %p sgl %u oob_h %u du %u oob_buf %p oob_b %u",
+ work_queue_buffer_pointer, header->num_sgl_entries,
+ header->inline_client_oob_size_in_dwords,
+ header->client_data_unit, work_request->inline_oob_data,
+ work_request->inline_oob_size_in_bytes);
+
+ p += sizeof(struct gdma_wqe_dma_oob);
+ if (work_request->inline_oob_data &&
+ work_request->inline_oob_size_in_bytes > 0) {
+ memcpy(p, work_request->inline_oob_data,
+ work_request->inline_oob_size_in_bytes);
+ if (client_oob_size > work_request->inline_oob_size_in_bytes)
+ memset(p + work_request->inline_oob_size_in_bytes, 0,
+ client_oob_size -
+ work_request->inline_oob_size_in_bytes);
+ }
+
+ return sizeof(struct gdma_wqe_dma_oob) + client_oob_size;
+}
+
+static uint32_t
+write_scatter_gather_list(uint8_t *work_queue_head_pointer,
+ uint8_t *work_queue_end_pointer,
+ uint8_t *work_queue_cur_pointer,
+ struct gdma_work_request *work_request)
+{
+ struct gdma_sgl_element *sge_list;
+ struct gdma_sgl_element dummy_sgl[1];
+ uint8_t *address;
+ uint32_t size;
+ uint32_t num_sge;
+ uint32_t size_to_queue_end;
+ uint32_t sge_list_size;
+
+ DRV_LOG(DEBUG, "work_queue_cur_pointer %p work_request->flags %x",
+ work_queue_cur_pointer, work_request->flags);
+
+ num_sge = work_request->num_sgl_elements;
+ sge_list = work_request->sgl;
+ size_to_queue_end = (uint32_t)(work_queue_end_pointer -
+ work_queue_cur_pointer);
+
+ if (num_sge == 0) {
+ /* Per spec, the case of an empty SGL should be handled as
+ * follows to avoid corrupted WQE errors:
+ * Write one dummy SGL entry
+ * Set the address to 1, leave the rest as 0
+ */
+ dummy_sgl[num_sge].address = 1;
+ dummy_sgl[num_sge].size = 0;
+ dummy_sgl[num_sge].memory_key = 0;
+ num_sge++;
+ sge_list = dummy_sgl;
+ }
+
+ sge_list_size = 0;
+ {
+ address = (uint8_t *)sge_list;
+ size = sizeof(struct gdma_sgl_element) * num_sge;
+ if (size_to_queue_end < size) {
+ memcpy(work_queue_cur_pointer, address,
+ size_to_queue_end);
+ work_queue_cur_pointer = work_queue_head_pointer;
+ address += size_to_queue_end;
+ size -= size_to_queue_end;
+ }
+
+ memcpy(work_queue_cur_pointer, address, size);
+ sge_list_size = size;
+ }
+
+ DRV_LOG(DEBUG, "sge %u address 0x%" PRIx64 " size %u key %u list_s %u",
+ num_sge, sge_list->address, sge_list->size,
+ sge_list->memory_key, sge_list_size);
+
+ return sge_list_size;
+}
+
+int gdma_post_work_request(struct mana_gdma_queue *queue,
+ struct gdma_work_request *work_req,
+ struct gdma_posted_wqe_info *wqe_info)
+{
+ uint32_t client_oob_size =
+ work_req->inline_oob_size_in_bytes >
+ INLINE_OOB_SMALL_SIZE_IN_BYTES ?
+ INLINE_OOB_LARGE_SIZE_IN_BYTES :
+ INLINE_OOB_SMALL_SIZE_IN_BYTES;
+
+ uint32_t sgl_data_size = sizeof(struct gdma_sgl_element) *
+ RTE_MAX((uint32_t)1, work_req->num_sgl_elements);
+ uint32_t wqe_size =
+ RTE_ALIGN(sizeof(struct gdma_wqe_dma_oob) +
+ client_oob_size + sgl_data_size,
+ GDMA_WQE_ALIGNMENT_UNIT_SIZE);
+ uint8_t *wq_buffer_pointer;
+ uint32_t queue_free_units = queue->count - (queue->head - queue->tail);
+
+ if (wqe_size / GDMA_WQE_ALIGNMENT_UNIT_SIZE > queue_free_units) {
+ DRV_LOG(DEBUG, "WQE size %u queue count %u head %u tail %u",
+ wqe_size, queue->count, queue->head, queue->tail);
+ return -EBUSY;
+ }
+
+ DRV_LOG(DEBUG, "client_oob_size %u sgl_data_size %u wqe_size %u",
+ client_oob_size, sgl_data_size, wqe_size);
+
+ if (wqe_info) {
+ wqe_info->wqe_index =
+ ((queue->head * GDMA_WQE_ALIGNMENT_UNIT_SIZE) &
+ (queue->size - 1)) / GDMA_WQE_ALIGNMENT_UNIT_SIZE;
+ wqe_info->unmasked_queue_offset = queue->head;
+ wqe_info->wqe_size_in_bu =
+ wqe_size / GDMA_WQE_ALIGNMENT_UNIT_SIZE;
+ }
+
+ wq_buffer_pointer = gdma_get_wqe_pointer(queue);
+ wq_buffer_pointer += write_dma_client_oob(wq_buffer_pointer, work_req,
+ client_oob_size);
+ if (wq_buffer_pointer >= ((uint8_t *)queue->buffer) + queue->size)
+ wq_buffer_pointer -= queue->size;
+
+ write_scatter_gather_list((uint8_t *)queue->buffer,
+ (uint8_t *)queue->buffer + queue->size,
+ wq_buffer_pointer, work_req);
+
+ queue->head += wqe_size / GDMA_WQE_ALIGNMENT_UNIT_SIZE;
+
+ return 0;
+}
+
+union gdma_doorbell_entry {
+ uint64_t as_uint64;
+
+ struct {
+ uint64_t id : 24;
+ uint64_t reserved : 8;
+ uint64_t tail_ptr : 31;
+ uint64_t arm : 1;
+ } cq;
+
+ struct {
+ uint64_t id : 24;
+ uint64_t wqe_cnt : 8;
+ uint64_t tail_ptr : 32;
+ } rq;
+
+ struct {
+ uint64_t id : 24;
+ uint64_t reserved : 8;
+ uint64_t tail_ptr : 32;
+ } sq;
+
+ struct {
+ uint64_t id : 16;
+ uint64_t reserved : 16;
+ uint64_t tail_ptr : 31;
+ uint64_t arm : 1;
+ } eq;
+}; /* HW DATA */
+
+#define DOORBELL_OFFSET_SQ 0x0
+#define DOORBELL_OFFSET_RQ 0x400
+#define DOORBELL_OFFSET_CQ 0x800
+#define DOORBELL_OFFSET_EQ 0xFF8
+
+int mana_ring_doorbell(void *db_page, enum gdma_queue_types queue_type,
+ uint32_t queue_id, uint32_t tail)
+{
+ uint8_t *addr = db_page;
+ union gdma_doorbell_entry e = {};
+
+ switch (queue_type) {
+ case gdma_queue_send:
+ e.sq.id = queue_id;
+ e.sq.tail_ptr = tail;
+ addr += DOORBELL_OFFSET_SQ;
+ break;
+
+ case gdma_queue_receive:
+ e.rq.id = queue_id;
+ e.rq.tail_ptr = tail;
+ e.rq.wqe_cnt = 1;
+ addr += DOORBELL_OFFSET_RQ;
+ break;
+
+ case gdma_queue_completion:
+ e.cq.id = queue_id;
+ e.cq.tail_ptr = tail;
+ e.cq.arm = 1;
+ addr += DOORBELL_OFFSET_CQ;
+ break;
+
+ default:
+ DRV_LOG(ERR, "Unsupported queue type %d", queue_type);
+ return -1;
+ }
+
+ rte_wmb();
+ DRV_LOG(DEBUG, "db_page %p addr %p queue_id %u type %u tail %u",
+ db_page, addr, queue_id, queue_type, tail);
+
+ rte_write64(e.as_uint64, addr);
+ return 0;
+}
+
+int gdma_poll_completion_queue(struct mana_gdma_queue *cq,
+ struct gdma_comp *comp)
+{
+ struct gdma_hardware_completion_entry *cqe;
+ uint32_t head = cq->head % cq->count;
+ uint32_t new_owner_bits, old_owner_bits;
+ uint32_t cqe_owner_bits;
+ struct gdma_hardware_completion_entry *buffer = cq->buffer;
+
+ cqe = &buffer[head];
+ new_owner_bits = (cq->head / cq->count) & COMPLETION_QUEUE_OWNER_MASK;
+ old_owner_bits = (cq->head / cq->count - 1) &
+ COMPLETION_QUEUE_OWNER_MASK;
+ cqe_owner_bits = cqe->owner_bits;
+
+ DRV_LOG(DEBUG, "comp cqe bits 0x%x owner bits 0x%x",
+ cqe_owner_bits, old_owner_bits);
+
+ if (cqe_owner_bits == old_owner_bits)
+ return 0; /* No new entry */
+
+ if (cqe_owner_bits != new_owner_bits) {
+ DRV_LOG(ERR, "CQ overflowed, ID %u cqe 0x%x new 0x%x",
+ cq->id, cqe_owner_bits, new_owner_bits);
+ return -1;
+ }
+
+ comp->work_queue_number = cqe->wq_num;
+ comp->send_work_queue = cqe->is_sq;
+
+ memcpy(comp->completion_data, cqe->dma_client_data, GDMA_COMP_DATA_SIZE);
+
+ cq->head++;
+
+ DRV_LOG(DEBUG, "comp new 0x%x old 0x%x cqe 0x%x wq %u sq %u head %u",
+ new_owner_bits, old_owner_bits, cqe_owner_bits,
+ comp->work_queue_number, comp->send_work_queue, cq->head);
+ return 1;
+}
diff --git a/drivers/net/mana/mana.h b/drivers/net/mana/mana.h
index 9e15b43275..d87358ab15 100644
--- a/drivers/net/mana/mana.h
+++ b/drivers/net/mana/mana.h
@@ -50,6 +50,178 @@ struct mana_shared_data {
#define MAX_RECEIVE_BUFFERS_PER_QUEUE 256
#define MAX_SEND_BUFFERS_PER_QUEUE 256
+#define GDMA_WQE_ALIGNMENT_UNIT_SIZE 32
+
+#define COMP_ENTRY_SIZE 64
+#define MAX_TX_WQE_SIZE 512
+#define MAX_RX_WQE_SIZE 256
+
+/* Values from the GDMA specification document, WQE format description */
+#define INLINE_OOB_SMALL_SIZE_IN_BYTES 8
+#define INLINE_OOB_LARGE_SIZE_IN_BYTES 24
+
+#define NOT_USING_CLIENT_DATA_UNIT 0
+
+enum gdma_queue_types {
+ gdma_queue_type_invalid = 0,
+ gdma_queue_send,
+ gdma_queue_receive,
+ gdma_queue_completion,
+ gdma_queue_event,
+ gdma_queue_type_max = 16,
+ /*Room for expansion */
+
+ /* This enum can be expanded to add more queue types but
+ * it's expected to be done in a contiguous manner.
+ * Failing that will result in unexpected behavior.
+ */
+};
+
+#define WORK_QUEUE_NUMBER_BASE_BITS 10
+
+struct gdma_header {
+ /* size of the entire gdma structure, including the entire length of
+ * the struct that is formed by extending other gdma struct. i.e.
+ * GDMA_BASE_SPEC extends gdma_header, GDMA_EVENT_QUEUE_SPEC extends
+ * GDMA_BASE_SPEC, StructSize for GDMA_EVENT_QUEUE_SPEC will be size of
+ * GDMA_EVENT_QUEUE_SPEC which includes size of GDMA_BASE_SPEC and size
+ * of gdma_header.
+ * Above example is for illustration purpose and is not in code
+ */
+ size_t struct_size;
+};
+
+/* The following macros are from GDMA SPEC 3.6, "Table 2: CQE data structure"
+ * and "Table 4: Event Queue Entry (EQE) data format"
+ */
+#define GDMA_COMP_DATA_SIZE 0x3C /* Must be a multiple of 4 */
+#define GDMA_COMP_DATA_SIZE_IN_UINT32 (GDMA_COMP_DATA_SIZE / 4)
+
+#define COMPLETION_QUEUE_ENTRY_WORK_QUEUE_INDEX 0
+#define COMPLETION_QUEUE_ENTRY_WORK_QUEUE_SIZE 24
+#define COMPLETION_QUEUE_ENTRY_SEND_WORK_QUEUE_INDEX 24
+#define COMPLETION_QUEUE_ENTRY_SEND_WORK_QUEUE_SIZE 1
+#define COMPLETION_QUEUE_ENTRY_OWNER_BITS_INDEX 29
+#define COMPLETION_QUEUE_ENTRY_OWNER_BITS_SIZE 3
+
+#define COMPLETION_QUEUE_OWNER_MASK \
+ ((1 << (COMPLETION_QUEUE_ENTRY_OWNER_BITS_SIZE)) - 1)
+
+struct gdma_comp {
+ struct gdma_header gdma_header;
+
+ /* Filled by GDMA core */
+ uint32_t completion_data[GDMA_COMP_DATA_SIZE_IN_UINT32];
+
+ /* Filled by GDMA core */
+ uint32_t work_queue_number;
+
+ /* Filled by GDMA core */
+ bool send_work_queue;
+};
+
+struct gdma_hardware_completion_entry {
+ char dma_client_data[GDMA_COMP_DATA_SIZE];
+ union {
+ uint32_t work_queue_owner_bits;
+ struct {
+ uint32_t wq_num : 24;
+ uint32_t is_sq : 1;
+ uint32_t reserved : 4;
+ uint32_t owner_bits : 3;
+ };
+ };
+}; /* HW DATA */
+
+struct gdma_posted_wqe_info {
+ struct gdma_header gdma_header;
+
+ /* size of the written wqe in basic units (32B), filled by GDMA core.
+ * Use this value to progress the work queue after the wqe is processed
+ * by hardware.
+ */
+ uint32_t wqe_size_in_bu;
+
+ /* At the time of writing the wqe to the work queue, the offset in the
+ * work queue buffer where by the wqe will be written. Each unit
+ * represents 32B of buffer space.
+ */
+ uint32_t wqe_index;
+
+ /* Unmasked offset in the queue to which the WQE was written.
+ * In 32 byte units.
+ */
+ uint32_t unmasked_queue_offset;
+};
+
+struct gdma_sgl_element {
+ uint64_t address;
+ uint32_t memory_key;
+ uint32_t size;
+};
+
+#define MAX_SGL_ENTRIES_FOR_TRANSMIT 30
+
+struct one_sgl {
+ struct gdma_sgl_element gdma_sgl[MAX_SGL_ENTRIES_FOR_TRANSMIT];
+};
+
+struct gdma_work_request {
+ struct gdma_header gdma_header;
+ struct gdma_sgl_element *sgl;
+ uint32_t num_sgl_elements;
+ uint32_t inline_oob_size_in_bytes;
+ void *inline_oob_data;
+ uint32_t flags; /* From _gdma_work_request_FLAGS */
+ uint32_t client_data_unit; /* For LSO, this is the MTU of the data */
+};
+
+enum mana_cqe_type {
+ CQE_INVALID = 0,
+};
+
+struct mana_cqe_header {
+ uint32_t cqe_type : 6;
+ uint32_t client_type : 2;
+ uint32_t vendor_err : 24;
+}; /* HW DATA */
+
+/* NDIS HASH Types */
+#define BIT(nr) (1 << (nr))
+#define NDIS_HASH_IPV4 BIT(0)
+#define NDIS_HASH_TCP_IPV4 BIT(1)
+#define NDIS_HASH_UDP_IPV4 BIT(2)
+#define NDIS_HASH_IPV6 BIT(3)
+#define NDIS_HASH_TCP_IPV6 BIT(4)
+#define NDIS_HASH_UDP_IPV6 BIT(5)
+#define NDIS_HASH_IPV6_EX BIT(6)
+#define NDIS_HASH_TCP_IPV6_EX BIT(7)
+#define NDIS_HASH_UDP_IPV6_EX BIT(8)
+
+#define MANA_HASH_L3 (NDIS_HASH_IPV4 | NDIS_HASH_IPV6 | NDIS_HASH_IPV6_EX)
+#define MANA_HASH_L4 \
+ (NDIS_HASH_TCP_IPV4 | NDIS_HASH_UDP_IPV4 | NDIS_HASH_TCP_IPV6 | \
+ NDIS_HASH_UDP_IPV6 | NDIS_HASH_TCP_IPV6_EX | NDIS_HASH_UDP_IPV6_EX)
+
+struct gdma_wqe_dma_oob {
+ uint32_t reserved:24;
+ uint32_t last_v_bytes:8;
+ union {
+ uint32_t flags;
+ struct {
+ uint32_t num_sgl_entries:8;
+ uint32_t inline_client_oob_size_in_dwords:3;
+ uint32_t client_oob_in_sgl:1;
+ uint32_t consume_credit:1;
+ uint32_t fence:1;
+ uint32_t reserved1:2;
+ uint32_t client_data_unit:14;
+ uint32_t check_sn:1;
+ uint32_t sgl_direct:1;
+ };
+ };
+};
+
struct mana_mr_cache {
uint32_t lkey;
uintptr_t addr;
@@ -190,12 +362,23 @@ extern int mana_logtype_init;
#define PMD_INIT_FUNC_TRACE() PMD_INIT_LOG(DEBUG, " >>")
+int mana_ring_doorbell(void *db_page, enum gdma_queue_types queue_type,
+ uint32_t queue_id, uint32_t tail);
+
+int gdma_post_work_request(struct mana_gdma_queue *queue,
+ struct gdma_work_request *work_req,
+ struct gdma_posted_wqe_info *wqe_info);
+uint8_t *gdma_get_wqe_pointer(struct mana_gdma_queue *queue);
+
uint16_t mana_rx_burst_removed(void *dpdk_rxq, struct rte_mbuf **pkts,
uint16_t pkts_n);
uint16_t mana_tx_burst_removed(void *dpdk_rxq, struct rte_mbuf **pkts,
uint16_t pkts_n);
+int gdma_poll_completion_queue(struct mana_gdma_queue *cq,
+ struct gdma_comp *comp);
+
struct mana_mr_cache *mana_find_pmd_mr(struct mana_mr_btree *local_tree,
struct mana_priv *priv,
struct rte_mbuf *mbuf);
diff --git a/drivers/net/mana/meson.build b/drivers/net/mana/meson.build
index 59b18923df..35b93d7b73 100644
--- a/drivers/net/mana/meson.build
+++ b/drivers/net/mana/meson.build
@@ -12,6 +12,7 @@ deps += ['pci', 'bus_pci', 'net', 'eal', 'kvargs']
sources += files(
'mana.c',
'mr.c',
+ 'gdma.c',
'mp.c',
)
--
2.17.1
next prev parent reply other threads:[~2022-07-06 0:30 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-06 0:28 [Patch v2 00/17] Introduce Microsoft Azure Network Adatper (MANA) PMD longli
2022-07-06 0:28 ` [Patch v2 01/17] net/mana: add basic driver, build environment and doc longli
2022-07-06 15:09 ` Stephen Hemminger
2022-07-06 16:07 ` Long Li
2022-07-06 16:19 ` David Marchand
2022-07-06 16:25 ` Long Li
2022-07-06 0:28 ` [Patch v2 02/17] net/mana: add device configuration and stop longli
2022-07-06 0:28 ` [Patch v2 03/17] net/mana: add function to report support ptypes longli
2022-07-06 0:28 ` [Patch v2 04/17] net/mana: add link update longli
2022-07-06 0:28 ` [Patch v2 05/17] net/mana: add function for device removal interrupts longli
2022-07-06 0:28 ` [Patch v2 06/17] net/mana: add device info longli
2022-07-06 0:28 ` [Patch v2 07/17] net/mana: add function to configure RSS longli
2022-07-06 0:28 ` [Patch v2 08/17] net/mana: add function to configure RX queues longli
2022-07-06 0:28 ` [Patch v2 09/17] net/mana: add function to configure TX queues longli
2022-07-06 0:28 ` [Patch v2 10/17] net/mana: implement memory registration longli
2022-07-06 0:28 ` longli [this message]
2022-07-06 0:28 ` [Patch v2 12/17] net/mana: add function to start/stop TX queues longli
2022-07-06 0:28 ` [Patch v2 13/17] net/mana: add function to start/stop RX queues longli
2022-07-06 0:28 ` [Patch v2 14/17] net/mana: add function to receive packets longli
2022-07-06 0:28 ` [Patch v2 15/17] net/mana: add function to send packets longli
2022-07-06 0:28 ` [Patch v2 16/17] net/mana: add function to start/stop device longli
2022-07-06 0:28 ` [Patch v2 17/17] net/mana: add function to report queue stats longli
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