[char-misc-next v2 2/7] mei: hbm: setup dma ring

From: Tomas Winkler
Date: Thu Nov 22 2018 - 06:12:33 EST


DMA ring is allocated upon HBM handshake and the ring parameters are set
via dedicated HBM_DMA_SETUP request command. The firmware will perform
its setup and respond with a status. On failure the DMA buffers are
released.

Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
---
drivers/misc/mei/hbm.c | 86 ++++++++++++++++++++++++++++++++++++++++--
drivers/misc/mei/hbm.h | 2 +
2 files changed, 85 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
index fe67381b34c3..b458c5612245 100644
--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -65,6 +65,7 @@ const char *mei_hbm_state_str(enum mei_hbm_state state)
MEI_HBM_STATE(IDLE);
MEI_HBM_STATE(STARTING);
MEI_HBM_STATE(STARTED);
+ MEI_HBM_STATE(DR_SETUP);
MEI_HBM_STATE(ENUM_CLIENTS);
MEI_HBM_STATE(CLIENT_PROPERTIES);
MEI_HBM_STATE(STOPPED);
@@ -295,6 +296,46 @@ int mei_hbm_start_req(struct mei_device *dev)
return 0;
}

+/**
+ * mei_hbm_dma_setup_req() - setup DMA request
+ * @dev: the device structure
+ *
+ * Return: 0 on success and < 0 on failure
+ */
+static int mei_hbm_dma_setup_req(struct mei_device *dev)
+{
+ struct mei_msg_hdr mei_hdr;
+ struct hbm_dma_setup_request req;
+ const size_t len = sizeof(struct hbm_dma_setup_request);
+ unsigned int i;
+ int ret;
+
+ mei_hbm_hdr(&mei_hdr, len);
+
+ memset(&req, 0, len);
+ req.hbm_cmd = MEI_HBM_DMA_SETUP_REQ_CMD;
+ for (i = 0; i < DMA_DSCR_NUM; i++) {
+ phys_addr_t paddr;
+
+ paddr = dev->dr_dscr[i].daddr;
+ req.dma_dscr[i].addr_hi = upper_32_bits(paddr);
+ req.dma_dscr[i].addr_lo = lower_32_bits(paddr);
+ req.dma_dscr[i].size = dev->dr_dscr[i].size;
+ }
+
+ ret = mei_hbm_write_message(dev, &mei_hdr, &req);
+ if (ret) {
+ dev_err(dev->dev, "dma setup request write failed: ret = %d.\n",
+ ret);
+ return ret;
+ }
+
+ dev->hbm_state = MEI_HBM_DR_SETUP;
+ dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
+ mei_schedule_stall_timer(dev);
+ return 0;
+}
+
/**
* mei_hbm_enum_clients_req - sends enumeration client request message.
*
@@ -1044,6 +1085,7 @@ int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
struct hbm_host_version_response *version_res;
struct hbm_props_response *props_res;
struct hbm_host_enum_response *enum_res;
+ struct hbm_dma_setup_response *dma_setup_res;
struct hbm_add_client_request *add_cl_req;
int ret;

@@ -1108,14 +1150,52 @@ int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
return -EPROTO;
}

- if (mei_hbm_enum_clients_req(dev)) {
- dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
- return -EIO;
+ if (dev->hbm_f_dr_supported) {
+ if (mei_dmam_ring_alloc(dev))
+ dev_info(dev->dev, "running w/o dma ring\n");
+ if (mei_dma_ring_is_allocated(dev)) {
+ if (mei_hbm_dma_setup_req(dev))
+ return -EIO;
+
+ wake_up(&dev->wait_hbm_start);
+ break;
+ }
}

+ dev->hbm_f_dr_supported = 0;
+ mei_dmam_ring_free(dev);
+
+ if (mei_hbm_enum_clients_req(dev))
+ return -EIO;
+
wake_up(&dev->wait_hbm_start);
break;

+ case MEI_HBM_DMA_SETUP_RES_CMD:
+ dev_dbg(dev->dev, "hbm: dma setup response: message received.\n");
+
+ dev->init_clients_timer = 0;
+
+ if (dev->hbm_state != MEI_HBM_DR_SETUP) {
+ dev_err(dev->dev, "hbm: dma setup response: state mismatch, [%d, %d]\n",
+ dev->dev_state, dev->hbm_state);
+ return -EPROTO;
+ }
+
+ dma_setup_res = (struct hbm_dma_setup_response *)mei_msg;
+
+ if (dma_setup_res->status) {
+ dev_info(dev->dev, "hbm: dma setup response: failure = %d %s\n",
+ dma_setup_res->status,
+ mei_hbm_status_str(dma_setup_res->status));
+ dev->hbm_f_dr_supported = 0;
+ mei_dmam_ring_free(dev);
+ }
+
+ if (mei_hbm_enum_clients_req(dev))
+ return -EIO;
+ break;
+
case CLIENT_CONNECT_RES_CMD:
dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
diff --git a/drivers/misc/mei/hbm.h b/drivers/misc/mei/hbm.h
index a2025a5083a3..0171a7e79bab 100644
--- a/drivers/misc/mei/hbm.h
+++ b/drivers/misc/mei/hbm.h
@@ -26,6 +26,7 @@ struct mei_cl;
*
* @MEI_HBM_IDLE : protocol not started
* @MEI_HBM_STARTING : start request message was sent
+ * @MEI_HBM_DR_SETUP : dma ring setup request message was sent
* @MEI_HBM_ENUM_CLIENTS : enumeration request was sent
* @MEI_HBM_CLIENT_PROPERTIES : acquiring clients properties
* @MEI_HBM_STARTED : enumeration was completed
@@ -34,6 +35,7 @@ struct mei_cl;
enum mei_hbm_state {
MEI_HBM_IDLE = 0,
MEI_HBM_STARTING,
+ MEI_HBM_DR_SETUP,
MEI_HBM_ENUM_CLIENTS,
MEI_HBM_CLIENT_PROPERTIES,
MEI_HBM_STARTED,
--
2.17.2