1 files changed, 360 insertions, 0 deletions

diff --git a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
index 253efba72275..831bfdf40068 100644
--- a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
+++ b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
@@ -15,37 +15,396 @@
 
 #include <linux/switchtec.h>
 #include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
 
 MODULE_DESCRIPTION("Microsemi Switchtec(tm) NTB Driver");
 MODULE_VERSION("0.1");
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Microsemi Corporation");
 
+static bool use_lut_mws;
+module_param(use_lut_mws, bool, 0644);
+MODULE_PARM_DESC(use_lut_mws,
+		 "Enable the use of the LUT based memory windows");
+
+#ifndef ioread64
+#ifdef readq
+#define ioread64 readq
+#else
+#define ioread64 _ioread64
+static inline u64 _ioread64(void __iomem *mmio)
+{
+	u64 low, high;
+
+	low = ioread32(mmio);
+	high = ioread32(mmio + sizeof(u32));
+	return low | (high << 32);
+}
+#endif
+#endif
+
+#ifndef iowrite64
+#ifdef writeq
+#define iowrite64 writeq
+#else
+#define iowrite64 _iowrite64
+static inline void _iowrite64(u64 val, void __iomem *mmio)
+{
+	iowrite32(val, mmio);
+	iowrite32(val >> 32, mmio + sizeof(u32));
+}
+#endif
+#endif
+
+#define SWITCHTEC_NTB_MAGIC 0x45CC0001
+#define MAX_MWS     128
+
+struct shared_mw {
+	u32 magic;
+	u32 partition_id;
+	u64 mw_sizes[MAX_MWS];
+};
+
+#define MAX_DIRECT_MW ARRAY_SIZE(((struct ntb_ctrl_regs *)(0))->bar_entry)
+#define LUT_SIZE SZ_64K
+
 struct switchtec_ntb {
 	struct switchtec_dev *stdev;
+
+	int self_partition;
+	int peer_partition;
+
+	struct ntb_info_regs __iomem *mmio_ntb;
+	struct ntb_ctrl_regs __iomem *mmio_ctrl;
+	struct ntb_dbmsg_regs __iomem *mmio_dbmsg;
+	struct ntb_ctrl_regs __iomem *mmio_self_ctrl;
+	struct ntb_ctrl_regs __iomem *mmio_peer_ctrl;
+	struct ntb_dbmsg_regs __iomem *mmio_self_dbmsg;
+
+	struct shared_mw *self_shared;
+	struct shared_mw __iomem *peer_shared;
+	dma_addr_t self_shared_dma;
+
+	int nr_direct_mw;
+	int nr_lut_mw;
+	int direct_mw_to_bar[MAX_DIRECT_MW];
+
+	int peer_nr_direct_mw;
+	int peer_nr_lut_mw;
+	int peer_direct_mw_to_bar[MAX_DIRECT_MW];
 };
 
+static int switchtec_ntb_part_op(struct switchtec_ntb *sndev,
+				 struct ntb_ctrl_regs __iomem *ctl,
+				 u32 op, int wait_status)
+{
+	static const char * const op_text[] = {
+		[NTB_CTRL_PART_OP_LOCK] = "lock",
+		[NTB_CTRL_PART_OP_CFG] = "configure",
+		[NTB_CTRL_PART_OP_RESET] = "reset",
+	};
+
+	int i;
+	u32 ps;
+	int status;
+
+	switch (op) {
+	case NTB_CTRL_PART_OP_LOCK:
+		status = NTB_CTRL_PART_STATUS_LOCKING;
+		break;
+	case NTB_CTRL_PART_OP_CFG:
+		status = NTB_CTRL_PART_STATUS_CONFIGURING;
+		break;
+	case NTB_CTRL_PART_OP_RESET:
+		status = NTB_CTRL_PART_STATUS_RESETTING;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	iowrite32(op, &ctl->partition_op);
+
+	for (i = 0; i < 1000; i++) {
+		if (msleep_interruptible(50) != 0) {
+			iowrite32(NTB_CTRL_PART_OP_RESET, &ctl->partition_op);
+			return -EINTR;
+		}
+
+		ps = ioread32(&ctl->partition_status) & 0xFFFF;
+
+		if (ps != status)
+			break;
+	}
+
+	if (ps == wait_status)
+		return 0;
+
+	if (ps == status) {
+		dev_err(&sndev->stdev->dev,
+			"Timed out while peforming %s (%d). (%08x)",
+			op_text[op], op,
+			ioread32(&ctl->partition_status));
+
+		return -ETIMEDOUT;
+	}
+
+	return -EIO;
+}
+
+static void switchtec_ntb_init_sndev(struct switchtec_ntb *sndev)
+{
+	u64 part_map;
+
+	sndev->self_partition = sndev->stdev->partition;
+
+	sndev->mmio_ntb = sndev->stdev->mmio_ntb;
+	part_map = ioread64(&sndev->mmio_ntb->ep_map);
+	part_map &= ~(1 << sndev->self_partition);
+	sndev->peer_partition = ffs(part_map) - 1;
+
+	dev_dbg(&sndev->stdev->dev, "Partition ID %d of %d (%llx)",
+		sndev->self_partition, sndev->stdev->partition_count,
+		part_map);
+
+	sndev->mmio_ctrl = (void * __iomem)sndev->mmio_ntb +
+		SWITCHTEC_NTB_REG_CTRL_OFFSET;
+	sndev->mmio_dbmsg = (void * __iomem)sndev->mmio_ntb +
+		SWITCHTEC_NTB_REG_DBMSG_OFFSET;
+
+	sndev->mmio_self_ctrl = &sndev->mmio_ctrl[sndev->self_partition];
+	sndev->mmio_peer_ctrl = &sndev->mmio_ctrl[sndev->peer_partition];
+	sndev->mmio_self_dbmsg = &sndev->mmio_dbmsg[sndev->self_partition];
+}
+
+static int map_bars(int *map, struct ntb_ctrl_regs __iomem *ctrl)
+{
+	int i;
+	int cnt = 0;
+
+	for (i = 0; i < ARRAY_SIZE(ctrl->bar_entry); i++) {
+		u32 r = ioread32(&ctrl->bar_entry[i].ctl);
+
+		if (r & NTB_CTRL_BAR_VALID)
+			map[cnt++] = i;
+	}
+
+	return cnt;
+}
+
+static void switchtec_ntb_init_mw(struct switchtec_ntb *sndev)
+{
+	sndev->nr_direct_mw = map_bars(sndev->direct_mw_to_bar,
+				       sndev->mmio_self_ctrl);
+
+	sndev->nr_lut_mw = ioread16(&sndev->mmio_self_ctrl->lut_table_entries);
+	sndev->nr_lut_mw = rounddown_pow_of_two(sndev->nr_lut_mw);
+
+	dev_dbg(&sndev->stdev->dev, "MWs: %d direct, %d lut",
+		sndev->nr_direct_mw, sndev->nr_lut_mw);
+
+	sndev->peer_nr_direct_mw = map_bars(sndev->peer_direct_mw_to_bar,
+					    sndev->mmio_peer_ctrl);
+
+	sndev->peer_nr_lut_mw =
+		ioread16(&sndev->mmio_peer_ctrl->lut_table_entries);
+	sndev->peer_nr_lut_mw = rounddown_pow_of_two(sndev->peer_nr_lut_mw);
+
+	dev_dbg(&sndev->stdev->dev, "Peer MWs: %d direct, %d lut",
+		sndev->peer_nr_direct_mw, sndev->peer_nr_lut_mw);
+
+}
+
+static int switchtec_ntb_init_req_id_table(struct switchtec_ntb *sndev)
+{
+	int rc = 0;
+	u16 req_id;
+	u32 error;
+
+	req_id = ioread16(&sndev->mmio_ntb->requester_id);
+
+	if (ioread32(&sndev->mmio_self_ctrl->req_id_table_size) < 2) {
+		dev_err(&sndev->stdev->dev,
+			"Not enough requester IDs available.");
+		return -EFAULT;
+	}
+
+	rc = switchtec_ntb_part_op(sndev, sndev->mmio_self_ctrl,
+				   NTB_CTRL_PART_OP_LOCK,
+				   NTB_CTRL_PART_STATUS_LOCKED);
+	if (rc)
+		return rc;
+
+	iowrite32(NTB_PART_CTRL_ID_PROT_DIS,
+		  &sndev->mmio_self_ctrl->partition_ctrl);
+
+	/*
+	 * Root Complex Requester ID (which is 0:00.0)
+	 */
+	iowrite32(0 << 16 | NTB_CTRL_REQ_ID_EN,
+		  &sndev->mmio_self_ctrl->req_id_table[0]);
+
+	/*
+	 * Host Bridge Requester ID (as read from the mmap address)
+	 */
+	iowrite32(req_id << 16 | NTB_CTRL_REQ_ID_EN,
+		  &sndev->mmio_self_ctrl->req_id_table[1]);
+
+	rc = switchtec_ntb_part_op(sndev, sndev->mmio_self_ctrl,
+				   NTB_CTRL_PART_OP_CFG,
+				   NTB_CTRL_PART_STATUS_NORMAL);
+	if (rc == -EIO) {
+		error = ioread32(&sndev->mmio_self_ctrl->req_id_error);
+		dev_err(&sndev->stdev->dev,
+			"Error setting up the requester ID table: %08x",
+			error);
+	}
+
+	return rc;
+}
+
+static void switchtec_ntb_init_shared(struct switchtec_ntb *sndev)
+{
+	int i;
+
+	memset(sndev->self_shared, 0, LUT_SIZE);
+	sndev->self_shared->magic = SWITCHTEC_NTB_MAGIC;
+	sndev->self_shared->partition_id = sndev->stdev->partition;
+
+	for (i = 0; i < sndev->nr_direct_mw; i++) {
+		int bar = sndev->direct_mw_to_bar[i];
+		resource_size_t sz = pci_resource_len(sndev->stdev->pdev, bar);
+
+		if (i == 0)
+			sz = min_t(resource_size_t, sz,
+				   LUT_SIZE * sndev->nr_lut_mw);
+
+		sndev->self_shared->mw_sizes[i] = sz;
+	}
+
+	for (i = 0; i < sndev->nr_lut_mw; i++) {
+		int idx = sndev->nr_direct_mw + i;
+
+		sndev->self_shared->mw_sizes[idx] = LUT_SIZE;
+	}
+}
+
+static int switchtec_ntb_init_shared_mw(struct switchtec_ntb *sndev)
+{
+	struct ntb_ctrl_regs __iomem *ctl = sndev->mmio_peer_ctrl;
+	int bar = sndev->direct_mw_to_bar[0];
+	u32 ctl_val;
+	int rc;
+
+	sndev->self_shared = dma_zalloc_coherent(&sndev->stdev->pdev->dev,
+						 LUT_SIZE,
+						 &sndev->self_shared_dma,
+						 GFP_KERNEL);
+	if (!sndev->self_shared) {
+		dev_err(&sndev->stdev->dev,
+			"unable to allocate memory for shared mw");
+		return -ENOMEM;
+	}
+
+	switchtec_ntb_init_shared(sndev);
+
+	rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
+				   NTB_CTRL_PART_STATUS_LOCKED);
+	if (rc)
+		goto unalloc_and_exit;
+
+	ctl_val = ioread32(&ctl->bar_entry[bar].ctl);
+	ctl_val &= 0xFF;
+	ctl_val |= NTB_CTRL_BAR_LUT_WIN_EN;
+	ctl_val |= ilog2(LUT_SIZE) << 8;
+	ctl_val |= (sndev->nr_lut_mw - 1) << 14;
+	iowrite32(ctl_val, &ctl->bar_entry[bar].ctl);
+
+	iowrite64((NTB_CTRL_LUT_EN | (sndev->self_partition << 1) |
+		   sndev->self_shared_dma),
+		  &ctl->lut_entry[0]);
+
+	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 shared MW: %08x / %08x",
+			bar_error, lut_error);
+		goto unalloc_and_exit;
+	}
+
+	sndev->peer_shared = pci_iomap(sndev->stdev->pdev, bar, LUT_SIZE);
+	if (!sndev->peer_shared) {
+		rc = -ENOMEM;
+		goto unalloc_and_exit;
+	}
+
+	dev_dbg(&sndev->stdev->dev, "Shared MW Ready");
+	return 0;
+
+unalloc_and_exit:
+	dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
+			  sndev->self_shared, sndev->self_shared_dma);
+
+	return rc;
+}
+
+static void switchtec_ntb_deinit_shared_mw(struct switchtec_ntb *sndev)
+{
+	if (sndev->peer_shared)
+		pci_iounmap(sndev->stdev->pdev, sndev->peer_shared);
+
+	if (sndev->self_shared)
+		dma_free_coherent(&sndev->stdev->pdev->dev, LUT_SIZE,
+				  sndev->self_shared,
+				  sndev->self_shared_dma);
+}
+
 static int switchtec_ntb_add(struct device *dev,
 			     struct class_interface *class_intf)
 {
 	struct switchtec_dev *stdev = to_stdev(dev);
 	struct switchtec_ntb *sndev;
+	int rc;
 
 	stdev->sndev = NULL;
 
 	if (stdev->pdev->class != MICROSEMI_NTB_CLASSCODE)
 		return -ENODEV;
 
+	if (stdev->partition_count != 2)
+		dev_warn(dev, "ntb driver only supports 2 partitions");
+
 	sndev = kzalloc_node(sizeof(*sndev), GFP_KERNEL, dev_to_node(dev));
 	if (!sndev)
 		return -ENOMEM;
 
 	sndev->stdev = stdev;
 
+	switchtec_ntb_init_sndev(sndev);
+	switchtec_ntb_init_mw(sndev);
+
+	rc = switchtec_ntb_init_req_id_table(sndev);
+	if (rc)
+		goto free_and_exit;
+
+	rc = switchtec_ntb_init_shared_mw(sndev);
+	if (rc)
+		goto free_and_exit;
+
 	stdev->sndev = sndev;
 	dev_info(dev, "NTB device registered");
 
 	return 0;
+
+free_and_exit:
+	kfree(sndev);
+	dev_err(dev, "failed to register ntb device: %d", rc);
+	return rc;
 }
 
 void switchtec_ntb_remove(struct device *dev,
@@ -58,6 +417,7 @@ void switchtec_ntb_remove(struct device *dev,
 		return;
 
 	stdev->sndev = NULL;
+	switchtec_ntb_deinit_shared_mw(sndev);
 	kfree(sndev);
 	dev_info(dev, "ntb device unregistered");
 }