target/linux/cns3xxx/patches-4.4/060-pcie_abort.patch

   1 --- a/arch/arm/mach-cns3xxx/pcie.c
   2 +++ b/arch/arm/mach-cns3xxx/pcie.c
   3 @@ -86,6 +86,79 @@ static void __iomem *cns3xxx_pci_map_bus
   4         return base + (where & 0xffc) + (devfn << 12);
   5  }
   6
   7 +static inline int check_master_abort(struct pci_bus *bus, unsigned int devfn, int where)
   8 +{
   9 +       struct cns3xxx_pcie *cnspci = pbus_to_cnspci(bus);
  10 +
  11 +  /* check PCI-compatible status register after access */
  12 +       if (cnspci->linked) {
  13 +               void __iomem *host_base;
  14 +               u32 sreg, ereg;
  15 +
  16 +               host_base = (void __iomem *) cnspci->cfg_bases[CNS3XXX_HOST_TYPE].virtual;
  17 +               sreg = __raw_readw(host_base + 0x6) & 0xF900;
  18 +               ereg = __raw_readl(host_base + 0x104); // Uncorrectable Error Status Reg
  19 +
  20 +               if (sreg | ereg) {
  21 +                       /* SREG:
  22 +                        *  BIT15 - Detected Parity Error
  23 +                        *  BIT14 - Signaled System Error
  24 +                        *  BIT13 - Received Master Abort
  25 +                        *  BIT12 - Received Target Abort
  26 +                        *  BIT11 - Signaled Target Abort
  27 +                        *  BIT08 - Master Data Parity Error
  28 +                        *
  29 +                        * EREG:
  30 +                        *  BIT20 - Unsupported Request
  31 +                        *  BIT19 - ECRC
  32 +                        *  BIT18 - Malformed TLP
  33 +                        *  BIT17 - Receiver Overflow
  34 +                        *  BIT16 - Unexpected Completion
  35 +                        *  BIT15 - Completer Abort
  36 +                        *  BIT14 - Completion Timeout
  37 +                        *  BIT13 - Flow Control Protocol Error
  38 +                        *  BIT12 - Poisoned TLP
  39 +                        *  BIT04 - Data Link Protocol Error
  40 +                        *
  41 +                        * TODO: see Documentation/pci-error-recovery.txt
  42 +                        *    implement error_detected handler
  43 +                        */
  44 +/*
  45 +                       printk("pci error: %04d:%02x:%02x.%02x sreg=0x%04x ereg=0x%08x", pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn), sreg, ereg);
  46 +                       if (sreg & BIT(15)) printk(" <PERR");
  47 +                       if (sreg & BIT(14)) printk(" >SERR");
  48 +                       if (sreg & BIT(13)) printk(" <MABRT");
  49 +                       if (sreg & BIT(12)) printk(" <TABRT");
  50 +                       if (sreg & BIT(11)) printk(" >TABRT");
  51 +                       if (sreg & BIT( 8)) printk(" MPERR");
  52 +
  53 +                       if (ereg & BIT(20)) printk(" Unsup");
  54 +                       if (ereg & BIT(19)) printk(" ECRC");
  55 +                       if (ereg & BIT(18)) printk(" MTLP");
  56 +                       if (ereg & BIT(17)) printk(" OFLOW");
  57 +                       if (ereg & BIT(16)) printk(" Unex");
  58 +                       if (ereg & BIT(15)) printk(" ABRT");
  59 +                       if (ereg & BIT(14)) printk(" COMPTO");
  60 +                       if (ereg & BIT(13)) printk(" FLOW");
  61 +                       if (ereg & BIT(12)) printk(" PTLP");
  62 +                       if (ereg & BIT( 4)) printk(" DLINK");
  63 +                       printk("\n");
  64 +*/
  65 +                       pr_debug("%s failed port%d sreg=0x%04x\n", __func__,
  66 +                               pci_domain_nr(bus), sreg);
  67 +
  68 +                       /* make sure the status bits are reset */
  69 +                       __raw_writew(sreg, host_base + 6);
  70 +                       __raw_writel(ereg, host_base + 0x104);
  71 +                       return 1;
  72 +               }
  73 +       }
  74 +       else
  75 +               return 1;
  76 +
  77 +  return 0;
  78 +}
  79 +
  80  static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
  81                                    int where, int size, u32 *val)
  82  {
  83 @@ -95,6 +168,11 @@ static int cns3xxx_pci_read_config(struc
  84
  85         ret = pci_generic_config_read32(bus, devfn, where, size, val);
  86
  87 +       if (check_master_abort(bus, devfn, where)) {
  88 +               printk(KERN_ERR "pci error: %04d:%02x:%02x.%02x %02x(%d)= master_abort on read\n", pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn), where, size);
  89 +               return PCIBIOS_DEVICE_NOT_FOUND;
  90 +       }
  91 +
  92         if (ret == PCIBIOS_SUCCESSFUL && !bus->number && !devfn &&
  93             (where & 0xffc) == PCI_CLASS_REVISION)
  94                 /*
  95 @@ -257,8 +335,14 @@ static void __init cns3xxx_pcie_hw_init(
  96  static int cns3xxx_pcie_abort_handler(unsigned long addr, unsigned int fsr,
  97                                       struct pt_regs *regs)
  98  {
  99 +#if 0
 100 +/* R14_ABORT = PC+4 for XSCALE but not ARM11MPCORE
 101 + * ignore imprecise aborts and use PCI-compatible Status register to
 102 + * determine errors instead
 103 + */
 104         if (fsr & (1 << 10))
 105                 regs->ARM_pc += 4;
 106 +#endif
 107         return 0;
 108  }
 109