Add crosslink initialization

Author: lsgunth

linux/switchtec.h

@@ -172,6 +172,15 @@ struct ntb_info_regs {
 	u16 reserved1;
 	u64 ep_map;
 	u16 requester_id;
+	u16 reserved2;
+	u32 reserved3[4];
+	struct {
+		u8 enabled;
+		u8 partition_vec_low;
+		u8 partition_vec_high;
+		u8 reserved1;
+		u32 reserved2[3];
+	} crosslink[48];
 } __packed;
 
 struct part_cfg_regs {

ntb_hw_switchtec.c

@@ -95,6 +95,8 @@ struct switchtec_ntb {
 	struct ntb_ctrl_regs __iomem *mmio_peer_ctrl;
 	struct ntb_dbmsg_regs __iomem *mmio_self_dbmsg;
 
+	void __iomem *mmio_xlink_win;
+
 	struct shared_mw *self_shared;
 	struct shared_mw __iomem *peer_shared;
 	dma_addr_t self_shared_dma;
@@ -442,6 +444,13 @@ static void switchtec_ntb_set_link_speed(struct switchtec_ntb *sndev)
 	sndev->link_width = min(self_width, peer_width);
 }
 
+static int crosslink_is_enabled(struct switchtec_ntb *sndev)
+{
+	struct ntb_info_regs __iomem *inf = sndev->mmio_ntb;
+
+	return ioread8(&inf->crosslink[sndev->self_partition].enabled);
+}
+
 enum {
 	LINK_MESSAGE = 0,
 	MSG_LINK_UP = 1,
@@ -774,8 +783,7 @@ static void switchtec_ntb_init_sndev(struct switchtec_ntb *sndev)
 
 static int config_rsvd_lut_win(struct switchtec_ntb *sndev,
 			       struct ntb_ctrl_regs __iomem *ctl,
-			       int lut_idx, int partition,
-			       dma_addr_t addr)
+			       int lut_idx, int partition, u64 addr)
 {
 	int bar = sndev->direct_mw_to_bar[0];
 	u32 ctl_val;
@@ -861,6 +869,181 @@ static int config_req_id_table(struct switchtec_ntb *sndev,
 	return 0;
 }
 
+static int crosslink_setup_mws(struct switchtec_ntb *sndev, int ntb_lut_idx,
+			       u64 *mw_addrs, int mw_count)
+{
+	int rc, i;
+	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_self_ctrl;
+	u64 addr;
+	size_t size, offset;
+	int bar;
+	int xlate_pos;
+	u32 ctl_val;
+
+	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
+				   NTB_CTRL_PART_STATUS_LOCKED);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < sndev->nr_lut_mw; i++) {
+		if (i == ntb_lut_idx)
+			continue;
+
+		addr = mw_addrs[0] + LUT_SIZE * i;
+
+		iowrite64((NTB_CTRL_LUT_EN | (sndev->peer_partition << 1) |
+			   addr),
+			  &ctl->lut_entry[i]);
+	}
+
+	sndev->nr_direct_mw = min_t(int, sndev->nr_direct_mw, mw_count);
+
+	for (i = 0; i < sndev->nr_direct_mw; i++) {
+		bar = sndev->direct_mw_to_bar[i];
+		offset = (i == 0) ? LUT_SIZE * sndev->nr_lut_mw : 0;
+		addr = mw_addrs[i] + offset;
+		size = pci_resource_len(sndev->ntb.pdev, bar) - offset;
+		xlate_pos = ilog2(size);
+
+		if (offset && size > offset)
+			size = offset;
+
+		ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
+		ctl_val |= NTB_CTRL_BAR_DIR_WIN_EN;
+
+		iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
+		iowrite32(xlate_pos | size, &ctl->bar_entry[bar].win_size);
+		iowrite64(sndev->peer_partition | addr,
+			  &ctl->bar_entry[bar].xlate_addr);
+	}
+
+	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_CFG,
+				   NTB_CTRL_PART_STATUS_NORMAL);
+	if (rc) {
+		u32 bar_error, lut_error;
+
+		bar_error = ioread32(&ctl->bar_error);
+		lut_error = ioread32(&ctl->lut_error);
+		dev_err(&sndev->stdev->dev,
+			"Error setting up cross link windows: %08x / %08x",
+			bar_error, lut_error);
+		return rc;
+	}
+
+	return 0;
+}
+
+static int crosslink_setup_req_ids(struct switchtec_ntb *sndev,
+	struct ntb_ctrl_regs __iomem *mmio_ctrl)
+{
+	int req_ids[16];
+	int i;
+	u32 proxy_id;
+
+	for (i = 0; i < ARRAY_SIZE(req_ids); i++) {
+		proxy_id = ioread32(&sndev->mmio_self_ctrl->req_id_table[i]);
+
+		if (!(proxy_id & NTB_CTRL_REQ_ID_EN))
+			break;
+
+		req_ids[i] = ((proxy_id >> 1) & 0xFF);
+	}
+
+	return config_req_id_table(sndev, mmio_ctrl, req_ids, i);
+}
+
+/*
+ * In crosslink configuration there is a virtual partition in the
+ * middle of the two switches. The BARs in this partition have to be
+ * enumerated and assigned addresses.
+ */
+static int crosslink_enum_partition(struct switchtec_ntb *sndev,
+				    u64 *bar_addrs)
+{
+	struct part_cfg_regs __iomem *part_cfg =
+		&sndev->stdev->mmio_part_cfg_all[sndev->peer_partition];
+	u32 pff = ioread32(&part_cfg->vep_pff_inst_id);
+	struct pff_csr_regs __iomem *mmio_pff =
+		&sndev->stdev->mmio_pff_csr[pff];
+	const u64 bar_space = 0x1000000000LL;
+	u64 bar_addr;
+	int bar_cnt = 0;
+	int i;
+
+	iowrite16(0x6, &mmio_pff->pcicmd);
+
+	for (i = 0; i < ARRAY_SIZE(mmio_pff->pci_bar64); i++) {
+		iowrite64(bar_space * i, &mmio_pff->pci_bar64[i]);
+		bar_addr = ioread64(&mmio_pff->pci_bar64[i]);
+		bar_addr &= ~0xf;
+
+		dev_dbg(&sndev->stdev->dev,
+			"Crosslink BAR%d addr: %llx\n",
+			i, bar_addr);
+
+		if (bar_addr != bar_space * i)
+			continue;
+
+		bar_addrs[bar_cnt++] = bar_addr;
+	}
+
+	return bar_cnt;
+}
+
+static int switchtec_ntb_init_crosslink(struct switchtec_ntb *sndev)
+{
+	int rc;
+	int bar = sndev->direct_mw_to_bar[0];
+	const int ntb_lut_idx = 1;
+	u64 bar_addrs[6];
+	u64 addr;
+	int bar_cnt;
+
+	if (!crosslink_is_enabled(sndev))
+		return 0;
+
+	dev_info(&sndev->stdev->dev, "Using crosslink configuration");
+
+	bar_cnt = crosslink_enum_partition(sndev, bar_addrs);
+	if (bar_cnt < sndev->nr_direct_mw + 1) {
+		dev_err(&sndev->stdev->dev,
+			"Error enumerating crosslink partition\n");
+		return -EINVAL;
+	}
+
+	addr = bar_addrs[0];
+	rc = config_rsvd_lut_win(sndev, sndev->mmio_self_ctrl, ntb_lut_idx,
+				 sndev->peer_partition, addr);
+	if (rc)
+		return rc;
+
+	rc = crosslink_setup_mws(sndev, ntb_lut_idx, &bar_addrs[1],
+				 bar_cnt - 1);
+	if (rc)
+		return rc;
+
+	rc = crosslink_setup_req_ids(sndev, sndev->mmio_peer_ctrl);
+	if (rc)
+		return rc;
+
+	sndev->mmio_xlink_win = pci_iomap_range(sndev->stdev->pdev, bar,
+						LUT_SIZE, LUT_SIZE);
+	if (!sndev->mmio_xlink_win) {
+		rc = -ENOMEM;
+		return rc;
+	}
+
+	sndev->nr_rsvd_luts++;
+
+	return 0;
+}
+
+static void switchtec_ntb_deinit_crosslink(struct switchtec_ntb *sndev)
+{
+	if (sndev->mmio_xlink_win)
+		pci_iounmap(sndev->stdev->pdev, sndev->mmio_xlink_win);
+}
+
 static int map_bars(int *map, struct ntb_ctrl_regs __iomem *ctrl)
 {
 	int i;
@@ -1147,17 +1330,22 @@ static int switchtec_ntb_add(struct device *dev,
 	sndev->stdev = stdev;
 	switchtec_ntb_init_sndev(sndev);
 	switchtec_ntb_init_mw(sndev);
-	switchtec_ntb_init_db(sndev);
-	switchtec_ntb_init_msgs(sndev);
 
 	rc = switchtec_ntb_init_req_id_table(sndev);
 	if (rc)
 		goto free_and_exit;
 
-	rc = switchtec_ntb_init_shared_mw(sndev);
+	rc = switchtec_ntb_init_crosslink(sndev);
 	if (rc)
 		goto free_and_exit;
 
+	switchtec_ntb_init_db(sndev);
+	switchtec_ntb_init_msgs(sndev);
+
+	rc = switchtec_ntb_init_shared_mw(sndev);
+	if (rc)
+		goto deinit_crosslink;
+
 	rc = switchtec_ntb_init_db_msg_irq(sndev);
 	if (rc)
 		goto deinit_shared_and_exit;
@@ -1176,6 +1364,8 @@ static int switchtec_ntb_add(struct device *dev,
 	switchtec_ntb_deinit_db_msg_irq(sndev);
 deinit_shared_and_exit:
 	switchtec_ntb_deinit_shared_mw(sndev);
+deinit_crosslink:
+	switchtec_ntb_deinit_crosslink(sndev);
 free_and_exit:
 	kfree(sndev);
 	dev_err(dev, "failed to register ntb device: %d", rc);
@@ -1196,6 +1386,7 @@ void switchtec_ntb_remove(struct device *dev,
 	ntb_unregister_device(&sndev->ntb);
 	switchtec_ntb_deinit_db_msg_irq(sndev);
 	switchtec_ntb_deinit_shared_mw(sndev);
+	switchtec_ntb_deinit_crosslink(sndev);
 	kfree(sndev);
 	dev_info(dev, "ntb device unregistered");
 }