NTB: debugfs device entry

Create a debugfs entry for the NTB device to log the basic device info,
as well as display the error count on a number of registers.

Signed-off-by: Jon Mason <jon.mason@intel.com>

3 files changed, 107 insertions, 2 deletions

diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c
index 372e08c4ffef..a3990363a171 100644
--- a/drivers/ntb/ntb_hw.c
+++ b/drivers/ntb/ntb_hw.c
@@ -1344,6 +1344,101 @@ static void ntb_free_callbacks(struct ntb_device *ndev)
         kfree(ndev->db_cb);
 }
 
+static ssize_t ntb_debugfs_read(struct file *filp, char __user *ubuf,
+                                size_t count, loff_t *offp)
+{
+        struct ntb_device *ndev;
+        char *buf;
+        ssize_t ret, offset, out_count;
+
+        out_count = 500;
+
+        buf = kmalloc(out_count, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+
+        ndev = filp->private_data;
+        offset = 0;
+        offset += snprintf(buf + offset, out_count - offset,
+                           "NTB Device Information:\n");
+        offset += snprintf(buf + offset, out_count - offset,
+                           "Connection Type - \t\t%s\n",
+                           ndev->conn_type == NTB_CONN_TRANSPARENT ?
+                           "Transparent" : (ndev->conn_type == NTB_CONN_B2B) ?
+                           "Back to back" : "Root Port");
+        offset += snprintf(buf + offset, out_count - offset,
+                           "Device Type - \t\t\t%s\n",
+                           ndev->dev_type == NTB_DEV_USD ?
+                           "DSD/USP" : "USD/DSP");
+        offset += snprintf(buf + offset, out_count - offset,
+                           "Max Number of Callbacks - \t%u\n",
+                           ntb_max_cbs(ndev));
+        offset += snprintf(buf + offset, out_count - offset,
+                           "Link Status - \t\t\t%s\n",
+                           ntb_hw_link_status(ndev) ? "Up" : "Down");
+        if (ntb_hw_link_status(ndev)) {
+                offset += snprintf(buf + offset, out_count - offset,
+                                   "Link Speed - \t\t\tPCI-E Gen %u\n",
+                                   ndev->link_speed);
+                offset += snprintf(buf + offset, out_count - offset,
+                                   "Link Width - \t\t\tx%u\n",
+                                   ndev->link_width);
+        }
+
+        if (ndev->hw_type != BWD_HW) {
+                u32 status32;
+                u16 status16;
+                int rc;
+
+                offset += snprintf(buf + offset, out_count - offset,
+                                   "\nNTB Device Statistics:\n");
+                offset += snprintf(buf + offset, out_count - offset,
+                                   "Upstream Memory Miss - \t%u\n",
+                                   readw(ndev->reg_base +
+                                         SNB_USMEMMISS_OFFSET));
+
+                offset += snprintf(buf + offset, out_count - offset,
+                                   "\nNTB Hardware Errors:\n");
+
+                rc = pci_read_config_word(ndev->pdev, SNB_DEVSTS_OFFSET,
+                                          &status16);
+                if (!rc)
+                        offset += snprintf(buf + offset, out_count - offset,
+                                           "DEVSTS - \t%#06x\n", status16);
+
+                rc = pci_read_config_word(ndev->pdev, SNB_LINK_STATUS_OFFSET,
+                                          &status16);
+                if (!rc)
+                        offset += snprintf(buf + offset, out_count - offset,
+                                           "LNKSTS - \t%#06x\n", status16);
+
+                rc = pci_read_config_dword(ndev->pdev, SNB_UNCERRSTS_OFFSET,
+                                           &status32);
+                if (!rc)
+                        offset += snprintf(buf + offset, out_count - offset,
+                                           "UNCERRSTS - \t%#010x\n", status32);
+
+                rc = pci_read_config_dword(ndev->pdev, SNB_CORERRSTS_OFFSET,
+                                           &status32);
+                if (!rc)
+                        offset += snprintf(buf + offset, out_count - offset,
+                                           "CORERRSTS - \t%#010x\n", status32);
+        }
+
+        if (offset > out_count)
+                offset = out_count;
+
+        ret = simple_read_from_buffer(ubuf, count, offp, buf, offset);
+        kfree(buf);
+        return ret;
+}
+
+static const struct file_operations ntb_debugfs_info = {
+        .owner = THIS_MODULE,
+        .open = simple_open,
+        .read = ntb_debugfs_read,
+};
+
 static void ntb_setup_debugfs(struct ntb_device *ndev)
 {
         if (!debugfs_initialized())
@@ -1354,6 +1449,11 @@ static void ntb_setup_debugfs(struct ntb_device *ndev)
 
         ndev->debugfs_dir = debugfs_create_dir(pci_name(ndev->pdev),
                                                debugfs_dir);
+        if (ndev->debugfs_dir)
+                ndev->debugfs_info = debugfs_create_file("info", S_IRUSR,
+                                                         ndev->debugfs_dir,
+                                                         ndev,
+                                                         &ntb_debugfs_info);
 }
 
 static void ntb_free_debugfs(struct ntb_device *ndev)
@@ -1542,4 +1642,5 @@ static struct pci_driver ntb_pci_driver = {
         .probe = ntb_pci_probe,
         .remove = ntb_pci_remove,
 };
+
 module_pci_driver(ntb_pci_driver);
diff --git a/drivers/ntb/ntb_hw.h b/drivers/ntb/ntb_hw.h
index 465517b7393e..ddbcbfda0f49 100644
--- a/drivers/ntb/ntb_hw.h
+++ b/drivers/ntb/ntb_hw.h
@@ -152,6 +152,7 @@ struct ntb_device {
         struct delayed_work lr_timer;
 
         struct dentry *debugfs_dir;
+        struct dentry *debugfs_info;
 };
 
 /**
diff --git a/drivers/ntb/ntb_regs.h b/drivers/ntb/ntb_regs.h
index 9774506419d7..07872057c76e 100644
--- a/drivers/ntb/ntb_regs.h
+++ b/drivers/ntb/ntb_regs.h
@@ -62,10 +62,13 @@
 
 #define SNB_DB_HW_LINK          0x8000
 
+#define SNB_UNCERRSTS_OFFSET    0x014C
+#define SNB_CORERRSTS_OFFSET    0x0158
+#define SNB_LINK_STATUS_OFFSET  0x01A2
 #define SNB_PCICMD_OFFSET       0x0504
 #define SNB_DEVCTRL_OFFSET      0x0598
+#define SNB_DEVSTS_OFFSET       0x059A
 #define SNB_SLINK_STATUS_OFFSET 0x05A2
-#define SNB_LINK_STATUS_OFFSET  0x01A2
 
 #define SNB_PBAR2LMT_OFFSET     0x0000
 #define SNB_PBAR4LMT_OFFSET     0x0008
@@ -84,7 +87,7 @@
 #define SNB_PDBMSK_OFFSET       0x0062
 #define SNB_SDOORBELL_OFFSET    0x0064
 #define SNB_SDBMSK_OFFSET       0x0066
-#define SNB_USMEMMISS           0x0070
+#define SNB_USMEMMISS_OFFSET    0x0070
 #define SNB_SPAD_OFFSET         0x0080
 #define SNB_SPADSEMA4_OFFSET    0x00c0
 #define SNB_WCCNTRL_OFFSET      0x00e0