#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,
return;
stdev->sndev = NULL;
+ switchtec_ntb_deinit_shared_mw(sndev);
kfree(sndev);
dev_info(dev, "ntb device unregistered");
}