mei: implement client dma setup.

Implement HBM message protocol to setup and tear down
DMA buffer on behalf of an client. On top there DMA
buffer allocation and its life time management.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210206144325.25682-5-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 124 insertions, 0 deletions

diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
index 6e748da7e55d..d0277c7fed10 100644
--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -595,6 +595,117 @@ static void mei_hbm_cl_notify(struct mei_device *dev,
 }
 
 /**
+ * mei_hbm_cl_dma_map_req - send client dma map request
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ *
+ * Return: 0 on success and -EIO on write failure
+ */
+int mei_hbm_cl_dma_map_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_client_dma_map_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+
+	req.hbm_cmd = MEI_HBM_CLIENT_DMA_MAP_REQ_CMD;
+	req.client_buffer_id = cl->dma.buffer_id;
+	req.address_lsb = lower_32_bits(cl->dma.daddr);
+	req.address_msb = upper_32_bits(cl->dma.daddr);
+	req.size = cl->dma.size;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret)
+		dev_err(dev->dev, "dma map request failed: ret = %d\n", ret);
+
+	return ret;
+}
+
+/**
+ * mei_hbm_cl_dma_unmap_req - send client dma unmap request
+ *
+ * @dev: the device structure
+ * @cl: mei host client
+ *
+ * Return: 0 on success and -EIO on write failure
+ */
+int mei_hbm_cl_dma_unmap_req(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_msg_hdr mei_hdr;
+	struct hbm_client_dma_unmap_request req;
+	int ret;
+
+	mei_hbm_hdr(&mei_hdr, sizeof(req));
+
+	memset(&req, 0, sizeof(req));
+
+	req.hbm_cmd = MEI_HBM_CLIENT_DMA_UNMAP_REQ_CMD;
+	req.client_buffer_id = cl->dma.buffer_id;
+
+	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+	if (ret)
+		dev_err(dev->dev, "dma unmap request failed: ret = %d\n", ret);
+
+	return ret;
+}
+
+static void mei_hbm_cl_dma_map_res(struct mei_device *dev,
+				   struct hbm_client_dma_response *res)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+
+	cl = NULL;
+	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
+		if (cb->fop_type != MEI_FOP_DMA_MAP)
+			continue;
+		if (!cb->cl->dma.buffer_id || cb->cl->dma_mapped)
+			continue;
+
+		cl = cb->cl;
+		break;
+	}
+	if (!cl)
+		return;
+
+	dev_dbg(dev->dev, "cl dma map result = %d\n", res->status);
+	cl->status = res->status;
+	if (!cl->status)
+		cl->dma_mapped = 1;
+	wake_up(&cl->wait);
+}
+
+static void mei_hbm_cl_dma_unmap_res(struct mei_device *dev,
+				     struct hbm_client_dma_response *res)
+{
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+
+	cl = NULL;
+	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
+		if (cb->fop_type != MEI_FOP_DMA_UNMAP)
+			continue;
+		if (!cb->cl->dma.buffer_id || !cb->cl->dma_mapped)
+			continue;
+
+		cl = cb->cl;
+		break;
+	}
+	if (!cl)
+		return;
+
+	dev_dbg(dev->dev, "cl dma unmap result = %d\n", res->status);
+	cl->status = res->status;
+	if (!cl->status)
+		cl->dma_mapped = 0;
+	wake_up(&cl->wait);
+}
+
+/**
  * mei_hbm_prop_req - request property for a single client
  *
  * @dev: the device structure
@@ -1133,6 +1244,7 @@ int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
 	struct mei_hbm_cl_cmd *cl_cmd;
 	struct hbm_client_connect_request *disconnect_req;
 	struct hbm_flow_control *fctrl;
+	struct hbm_client_dma_response *client_dma_res;
 
 	/* read the message to our buffer */
 	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
@@ -1459,6 +1571,18 @@ int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
 		mei_hbm_cl_notify(dev, cl_cmd);
 		break;
 
+	case MEI_HBM_CLIENT_DMA_MAP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client dma map response: message received.\n");
+		client_dma_res = (struct hbm_client_dma_response *)mei_msg;
+		mei_hbm_cl_dma_map_res(dev, client_dma_res);
+		break;
+
+	case MEI_HBM_CLIENT_DMA_UNMAP_RES_CMD:
+		dev_dbg(dev->dev, "hbm: client dma unmap response: message received.\n");
+		client_dma_res = (struct hbm_client_dma_response *)mei_msg;
+		mei_hbm_cl_dma_unmap_res(dev, client_dma_res);
+		break;
+
 	default:
 		WARN(1, "hbm: wrong command %d\n", mei_msg->hbm_cmd);
 		return -EPROTO;