1 files changed, 144 insertions, 13 deletions

diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index 55943fcdaeb8..016588a6f5ed 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c
@@ -22,6 +22,7 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  */
 
+#include <linux/delay.h>
 #include <linux/export.h>
 #include <linux/gfp.h>
 #include <linux/init.h>
@@ -567,30 +568,132 @@ void eeh_pe_state_clear(struct eeh_pe *pe, int state)
         eeh_pe_traverse(pe, __eeh_pe_state_clear, &state);
 }
 
-/**
- * eeh_restore_one_device_bars - Restore the Base Address Registers for one device
- * @data: EEH device
- * @flag: Unused
+/*
+ * Some PCI bridges (e.g. PLX bridges) have primary/secondary
+ * buses assigned explicitly by firmware, and we probably have
+ * lost that after reset. So we have to delay the check until
+ * the PCI-CFG registers have been restored for the parent
+ * bridge.
  *
- * Loads the PCI configuration space base address registers,
- * the expansion ROM base address, the latency timer, and etc.
- * from the saved values in the device node.
+ * Don't use normal PCI-CFG accessors, which probably has been
+ * blocked on normal path during the stage. So we need utilize
+ * eeh operations, which is always permitted.
  */
-static void *eeh_restore_one_device_bars(void *data, void *flag)
+static void eeh_bridge_check_link(struct pci_dev *pdev,
+                                  struct device_node *dn)
+{
+        int cap;
+        uint32_t val;
+        int timeout = 0;
+
+        /*
+         * We only check root port and downstream ports of
+         * PCIe switches
+         */
+        if (!pci_is_pcie(pdev) ||
+            (pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT &&
+             pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM))
+                return;
+
+        pr_debug("%s: Check PCIe link for %s ...\n",
+                 __func__, pci_name(pdev));
+
+        /* Check slot status */
+        cap = pdev->pcie_cap;
+        eeh_ops->read_config(dn, cap + PCI_EXP_SLTSTA, 2, &val);
+        if (!(val & PCI_EXP_SLTSTA_PDS)) {
+                pr_debug("  No card in the slot (0x%04x) !\n", val);
+                return;
+        }
+
+        /* Check power status if we have the capability */
+        eeh_ops->read_config(dn, cap + PCI_EXP_SLTCAP, 2, &val);
+        if (val & PCI_EXP_SLTCAP_PCP) {
+                eeh_ops->read_config(dn, cap + PCI_EXP_SLTCTL, 2, &val);
+                if (val & PCI_EXP_SLTCTL_PCC) {
+                        pr_debug("  In power-off state, power it on ...\n");
+                        val &= ~(PCI_EXP_SLTCTL_PCC | PCI_EXP_SLTCTL_PIC);
+                        val |= (0x0100 & PCI_EXP_SLTCTL_PIC);
+                        eeh_ops->write_config(dn, cap + PCI_EXP_SLTCTL, 2, val);
+                        msleep(2 * 1000);
+                }
+        }
+
+        /* Enable link */
+        eeh_ops->read_config(dn, cap + PCI_EXP_LNKCTL, 2, &val);
+        val &= ~PCI_EXP_LNKCTL_LD;
+        eeh_ops->write_config(dn, cap + PCI_EXP_LNKCTL, 2, val);
+
+        /* Check link */
+        eeh_ops->read_config(dn, cap + PCI_EXP_LNKCAP, 4, &val);
+        if (!(val & PCI_EXP_LNKCAP_DLLLARC)) {
+                pr_debug("  No link reporting capability (0x%08x) \n", val);
+                msleep(1000);
+                return;
+        }
+
+        /* Wait the link is up until timeout (5s) */
+        timeout = 0;
+        while (timeout < 5000) {
+                msleep(20);
+                timeout += 20;
+
+                eeh_ops->read_config(dn, cap + PCI_EXP_LNKSTA, 2, &val);
+                if (val & PCI_EXP_LNKSTA_DLLLA)
+                        break;
+        }
+
+        if (val & PCI_EXP_LNKSTA_DLLLA)
+                pr_debug("  Link up (%s)\n",
+                         (val & PCI_EXP_LNKSTA_CLS_2_5GB) ? "2.5GB" : "5GB");
+        else
+                pr_debug("  Link not ready (0x%04x)\n", val);
+}
+
+#define BYTE_SWAP(OFF)  (8*((OFF)/4)+3-(OFF))
+#define SAVED_BYTE(OFF) (((u8 *)(edev->config_space))[BYTE_SWAP(OFF)])
+
+static void eeh_restore_bridge_bars(struct pci_dev *pdev,
+                                    struct eeh_dev *edev,
+                                    struct device_node *dn)
+{
+        int i;
+
+        /*
+         * Device BARs: 0x10 - 0x18
+         * Bus numbers and windows: 0x18 - 0x30
+         */
+        for (i = 4; i < 13; i++)
+                eeh_ops->write_config(dn, i*4, 4, edev->config_space[i]);
+        /* Rom: 0x38 */
+        eeh_ops->write_config(dn, 14*4, 4, edev->config_space[14]);
+
+        /* Cache line & Latency timer: 0xC 0xD */
+        eeh_ops->write_config(dn, PCI_CACHE_LINE_SIZE, 1,
+                SAVED_BYTE(PCI_CACHE_LINE_SIZE));
+        eeh_ops->write_config(dn, PCI_LATENCY_TIMER, 1,
+                SAVED_BYTE(PCI_LATENCY_TIMER));
+        /* Max latency, min grant, interrupt ping and line: 0x3C */
+        eeh_ops->write_config(dn, 15*4, 4, edev->config_space[15]);
+
+        /* PCI Command: 0x4 */
+        eeh_ops->write_config(dn, PCI_COMMAND, 4, edev->config_space[1]);
+
+        /* Check the PCIe link is ready */
+        eeh_bridge_check_link(pdev, dn);
+}
+
+static void eeh_restore_device_bars(struct eeh_dev *edev,
+                                    struct device_node *dn)
 {
         int i;
         u32 cmd;
-        struct eeh_dev *edev = (struct eeh_dev *)data;
-        struct device_node *dn = eeh_dev_to_of_node(edev);
 
         for (i = 4; i < 10; i++)
                 eeh_ops->write_config(dn, i*4, 4, edev->config_space[i]);
         /* 12 == Expansion ROM Address */
         eeh_ops->write_config(dn, 12*4, 4, edev->config_space[12]);
 
-#define BYTE_SWAP(OFF) (8*((OFF)/4)+3-(OFF))
-#define SAVED_BYTE(OFF) (((u8 *)(edev->config_space))[BYTE_SWAP(OFF)])
-
         eeh_ops->write_config(dn, PCI_CACHE_LINE_SIZE, 1,
                 SAVED_BYTE(PCI_CACHE_LINE_SIZE));
         eeh_ops->write_config(dn, PCI_LATENCY_TIMER, 1,
@@ -613,6 +716,34 @@ static void *eeh_restore_one_device_bars(void *data, void *flag)
         else
                 cmd &= ~PCI_COMMAND_SERR;
         eeh_ops->write_config(dn, PCI_COMMAND, 4, cmd);
+}
+
+/**
+ * eeh_restore_one_device_bars - Restore the Base Address Registers for one device
+ * @data: EEH device
+ * @flag: Unused
+ *
+ * Loads the PCI configuration space base address registers,
+ * the expansion ROM base address, the latency timer, and etc.
+ * from the saved values in the device node.
+ */
+static void *eeh_restore_one_device_bars(void *data, void *flag)
+{
+        struct pci_dev *pdev = NULL;
+        struct eeh_dev *edev = (struct eeh_dev *)data;
+        struct device_node *dn = eeh_dev_to_of_node(edev);
+
+        /* Trace the PCI bridge */
+        if (eeh_probe_mode_dev()) {
+                pdev = eeh_dev_to_pci_dev(edev);
+                if (pdev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
+                        pdev = NULL;
+        }
+
+        if (pdev)
+                eeh_restore_bridge_bars(pdev, edev, dn);
+        else
+                eeh_restore_device_bars(edev, dn);
 
         return NULL;
 }