dmaengine: ioatdma: add PCIe AER handlers

Adding AER handlers in order to handle any PCIe errors.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 86 insertions, 2 deletions

diff --git a/drivers/dma/ioat/init.c b/drivers/dma/ioat/init.c
index 793c5dd6a0e7..4ef0c5e07912 100644
--- a/drivers/dma/ioat/init.c
+++ b/drivers/dma/ioat/init.c
@@ -27,6 +27,7 @@
 #include <linux/workqueue.h>
 #include <linux/prefetch.h>
 #include <linux/dca.h>
+#include <linux/aer.h>
 #include "dma.h"
 #include "registers.h"
 #include "hw.h"
@@ -1211,14 +1212,91 @@ static void ioat_shutdown(struct pci_dev *pdev)
         ioat_disable_interrupts(ioat_dma);
 }
 
+void ioat_resume(struct ioatdma_device *ioat_dma)
+{
+        struct ioatdma_chan *ioat_chan;
+        u32 chanerr;
+        int i;
+
+        for (i = 0; i < IOAT_MAX_CHANS; i++) {
+                ioat_chan = ioat_dma->idx[i];
+                if (!ioat_chan)
+                        continue;
+
+                spin_lock_bh(&ioat_chan->prep_lock);
+                clear_bit(IOAT_CHAN_DOWN, &ioat_chan->state);
+                spin_unlock_bh(&ioat_chan->prep_lock);
+
+                chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
+                writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
+
+                /* no need to reset as shutdown already did that */
+        }
+}
+
 #define DRV_NAME "ioatdma"
 
+static pci_ers_result_t ioat_pcie_error_detected(struct pci_dev *pdev,
+                                                 enum pci_channel_state error)
+{
+        dev_dbg(&pdev->dev, "%s: PCIe AER error %d\n", DRV_NAME, error);
+
+        /* quiesce and block I/O */
+        ioat_shutdown(pdev);
+
+        return PCI_ERS_RESULT_NEED_RESET;
+}
+
+static pci_ers_result_t ioat_pcie_error_slot_reset(struct pci_dev *pdev)
+{
+        pci_ers_result_t result = PCI_ERS_RESULT_RECOVERED;
+        int err;
+
+        dev_dbg(&pdev->dev, "%s post reset handling\n", DRV_NAME);
+
+        if (pci_enable_device_mem(pdev) < 0) {
+                dev_err(&pdev->dev,
+                        "Failed to enable PCIe device after reset.\n");
+                result = PCI_ERS_RESULT_DISCONNECT;
+        } else {
+                pci_set_master(pdev);
+                pci_restore_state(pdev);
+                pci_save_state(pdev);
+                pci_wake_from_d3(pdev, false);
+        }
+
+        err = pci_cleanup_aer_uncorrect_error_status(pdev);
+        if (err) {
+                dev_err(&pdev->dev,
+                        "AER uncorrect error status clear failed: %#x\n", err);
+        }
+
+        return result;
+}
+
+static void ioat_pcie_error_resume(struct pci_dev *pdev)
+{
+        struct ioatdma_device *ioat_dma = pci_get_drvdata(pdev);
+
+        dev_dbg(&pdev->dev, "%s: AER handling resuming\n", DRV_NAME);
+
+        /* initialize and bring everything back */
+        ioat_resume(ioat_dma);
+}
+
+static const struct pci_error_handlers ioat_err_handler = {
+        .error_detected = ioat_pcie_error_detected,
+        .slot_reset = ioat_pcie_error_slot_reset,
+        .resume = ioat_pcie_error_resume,
+};
+
 static struct pci_driver ioat_pci_driver = {
         .name           = DRV_NAME,
         .id_table       = ioat_pci_tbl,
         .probe          = ioat_pci_probe,
         .remove         = ioat_remove,
         .shutdown       = ioat_shutdown,
+        .err_handler    = &ioat_err_handler,
 };
 
 static struct ioatdma_device *
@@ -1271,13 +1349,17 @@ static int ioat_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
         pci_set_drvdata(pdev, device);
 
         device->version = readb(device->reg_base + IOAT_VER_OFFSET);
-        if (device->version >= IOAT_VER_3_0)
+        if (device->version >= IOAT_VER_3_0) {
                 err = ioat3_dma_probe(device, ioat_dca_enabled);
-        else
+
+                if (device->version >= IOAT_VER_3_3)
+                        pci_enable_pcie_error_reporting(pdev);
+        } else
                 return -ENODEV;
 
         if (err) {
                 dev_err(dev, "Intel(R) I/OAT DMA Engine init failed\n");
+                pci_disable_pcie_error_reporting(pdev);
                 return -ENODEV;
         }
 
@@ -1297,6 +1379,8 @@ static void ioat_remove(struct pci_dev *pdev)
                 free_dca_provider(device->dca);
                 device->dca = NULL;
         }
+
+        pci_disable_pcie_error_reporting(pdev);
         ioat_dma_remove(device);
 }