Subject: [Patch v2 04/12] net: mana: Add functions for allocating doorbell page from GDMA

From: [email-masked]
Date: Tue, 24 May 2022 01:56:04 -0700

From: Long Li <[email-masked]>

The RDMA device needs to allocate doorbell pages for each user context.
Implement those functions and expose them for use by the RDMA driver.

Signed-off-by: Long Li <[email-masked]>
---
 drivers/net/ethernet/microsoft/mana/gdma.h    | 29 ++++++++++
 .../net/ethernet/microsoft/mana/gdma_main.c   | 54 +++++++++++++++++++
 2 files changed, 83 insertions(+)

diff --git a/drivers/net/ethernet/microsoft/mana/gdma.h b/drivers/net/ethernet/microsoft/mana/gdma.h
index c724ca410fcb..f945755760dc 100644
--- a/drivers/net/ethernet/microsoft/mana/gdma.h
+++ b/drivers/net/ethernet/microsoft/mana/gdma.h
@@ -22,11 +22,15 @@ enum gdma_request_type {
 	GDMA_GENERATE_TEST_EQE		= 10,
 	GDMA_CREATE_QUEUE		= 12,
 	GDMA_DISABLE_QUEUE		= 13,
+	GDMA_ALLOCATE_RESOURCE_RANGE	= 22,
+	GDMA_DESTROY_RESOURCE_RANGE	= 24,
 	GDMA_CREATE_DMA_REGION		= 25,
 	GDMA_DMA_REGION_ADD_PAGES	= 26,
 	GDMA_DESTROY_DMA_REGION		= 27,
 };
 
+#define GDMA_RESOURCE_DOORBELL_PAGE	27
+
 enum gdma_queue_type {
 	GDMA_INVALID_QUEUE,
 	GDMA_SQ,
@@ -568,6 +572,26 @@ struct gdma_register_device_resp {
 	u32 db_id;
 }; /* HW DATA */
 
+struct gdma_allocate_resource_range_req {
+	struct gdma_req_hdr hdr;
+	u32 resource_type;
+	u32 num_resources;
+	u32 alignment;
+	u32 allocated_resources;
+};
+
+struct gdma_allocate_resource_range_resp {
+	struct gdma_resp_hdr hdr;
+	u32 allocated_resources;
+};
+
+struct gdma_destroy_resource_range_req {
+	struct gdma_req_hdr hdr;
+	u32 resource_type;
+	u32 num_resources;
+	u32 allocated_resources;
+};
+
 /* GDMA_CREATE_QUEUE */
 struct gdma_create_queue_req {
 	struct gdma_req_hdr hdr;
@@ -676,4 +700,9 @@ void mana_gd_free_memory(struct gdma_mem_info *gmi);
 
 int mana_gd_send_request(struct gdma_context *gc, u32 req_len, const void *req,
 			 u32 resp_len, void *resp);
+
+int mana_gd_allocate_doorbell_page(struct gdma_context *gc, int *doorbell_page);
+
+int mana_gd_destroy_doorbell_page(struct gdma_context *gc, int doorbell_page);
+
 #endif /* _GDMA_H */
diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c
index 9fafaa0c8e76..86ffe0e39df0 100644
--- a/drivers/net/ethernet/microsoft/mana/gdma_main.c
+++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c
@@ -153,6 +153,60 @@ void mana_gd_free_memory(struct gdma_mem_info *gmi)
 			  gmi->dma_handle);
 }
 
+int mana_gd_destroy_doorbell_page(struct gdma_context *gc, int doorbell_page)
+{
+	struct gdma_destroy_resource_range_req req = {};
+	struct gdma_resp_hdr resp = {};
+	int err;
+
+	mana_gd_init_req_hdr(&req.hdr, GDMA_DESTROY_RESOURCE_RANGE,
+			     sizeof(req), sizeof(resp));
+
+	req.resource_type = GDMA_RESOURCE_DOORBELL_PAGE;
+	req.num_resources = 1;
+	req.allocated_resources = doorbell_page;
+
+	err = mana_gd_send_request(gc, sizeof(req), &req, sizeof(resp), &resp);
+	if (err || resp.status) {
+		dev_err(gc->dev,
+			"Failed to destroy doorbell page: ret %d, 0x%x\n",
+			err, resp.status);
+		return err ? err : -EPROTO;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(mana_gd_destroy_doorbell_page);
+
+int mana_gd_allocate_doorbell_page(struct gdma_context *gc,
+				   int *doorbell_page)
+{
+	struct gdma_allocate_resource_range_req req = {};
+	struct gdma_allocate_resource_range_resp resp = {};
+	int err;
+
+	mana_gd_init_req_hdr(&req.hdr, GDMA_ALLOCATE_RESOURCE_RANGE,
+			     sizeof(req), sizeof(resp));
+
+	req.resource_type = GDMA_RESOURCE_DOORBELL_PAGE;
+	req.num_resources = 1;
+	req.alignment = 0;
+	req.allocated_resources = 0; // have GDMA start searching from 0
+
+	err = mana_gd_send_request(gc, sizeof(req), &req, sizeof(resp), &resp);
+	if (err || resp.hdr.status) { // resp.hdr.status should be >=0
+		dev_err(gc->dev,
+			"Failed to allocate doorbell page: ret %d, 0x%x\n",
+			err, resp.hdr.status);
+		return err ? err : -EPROTO;
+	}
+
+	*doorbell_page = resp.allocated_resources;
+
+	return 0;
+}
+EXPORT_SYMBOL(mana_gd_allocate_doorbell_page);
+
 static int mana_gd_create_hw_eq(struct gdma_context *gc,
 				struct gdma_queue *queue)
 {
-- 
2.17.1