Openwrt/target/linux/cns3xxx/patches-4.19/060-pcie_abort.patch
Koen Vandeputte c6bebe1a94 cns3xxx: add support for kernel 4.19
Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
2019-01-28 18:17:32 +01:00

110 lines
3.5 KiB
Diff

--- a/arch/arm/mach-cns3xxx/pcie.c
+++ b/arch/arm/mach-cns3xxx/pcie.c
@@ -86,6 +86,79 @@ static void __iomem *cns3xxx_pci_map_bus
return base + where + (devfn << 12);
}
+static inline int check_master_abort(struct pci_bus *bus, unsigned int devfn, int where)
+{
+ struct cns3xxx_pcie *cnspci = pbus_to_cnspci(bus);
+
+ /* check PCI-compatible status register after access */
+ if (cnspci->linked) {
+ void __iomem *host_base;
+ u32 sreg, ereg;
+
+ host_base = (void __iomem *) cnspci->cfg_bases[CNS3XXX_HOST_TYPE].virtual;
+ sreg = __raw_readw(host_base + 0x6) & 0xF900;
+ ereg = __raw_readl(host_base + 0x104); // Uncorrectable Error Status Reg
+
+ if (sreg | ereg) {
+ /* SREG:
+ * BIT15 - Detected Parity Error
+ * BIT14 - Signaled System Error
+ * BIT13 - Received Master Abort
+ * BIT12 - Received Target Abort
+ * BIT11 - Signaled Target Abort
+ * BIT08 - Master Data Parity Error
+ *
+ * EREG:
+ * BIT20 - Unsupported Request
+ * BIT19 - ECRC
+ * BIT18 - Malformed TLP
+ * BIT17 - Receiver Overflow
+ * BIT16 - Unexpected Completion
+ * BIT15 - Completer Abort
+ * BIT14 - Completion Timeout
+ * BIT13 - Flow Control Protocol Error
+ * BIT12 - Poisoned TLP
+ * BIT04 - Data Link Protocol Error
+ *
+ * TODO: see Documentation/pci-error-recovery.txt
+ * implement error_detected handler
+ */
+/*
+ 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);
+ if (sreg & BIT(15)) printk(" <PERR");
+ if (sreg & BIT(14)) printk(" >SERR");
+ if (sreg & BIT(13)) printk(" <MABRT");
+ if (sreg & BIT(12)) printk(" <TABRT");
+ if (sreg & BIT(11)) printk(" >TABRT");
+ if (sreg & BIT( 8)) printk(" MPERR");
+
+ if (ereg & BIT(20)) printk(" Unsup");
+ if (ereg & BIT(19)) printk(" ECRC");
+ if (ereg & BIT(18)) printk(" MTLP");
+ if (ereg & BIT(17)) printk(" OFLOW");
+ if (ereg & BIT(16)) printk(" Unex");
+ if (ereg & BIT(15)) printk(" ABRT");
+ if (ereg & BIT(14)) printk(" COMPTO");
+ if (ereg & BIT(13)) printk(" FLOW");
+ if (ereg & BIT(12)) printk(" PTLP");
+ if (ereg & BIT( 4)) printk(" DLINK");
+ printk("\n");
+*/
+ pr_debug("%s failed port%d sreg=0x%04x\n", __func__,
+ pci_domain_nr(bus), sreg);
+
+ /* make sure the status bits are reset */
+ __raw_writew(sreg, host_base + 6);
+ __raw_writel(ereg, host_base + 0x104);
+ return 1;
+ }
+ }
+ else
+ return 1;
+
+ return 0;
+}
+
static int cns3xxx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
@@ -95,6 +168,11 @@ static int cns3xxx_pci_read_config(struc
ret = pci_generic_config_read(bus, devfn, where, size, val);
+ if (check_master_abort(bus, devfn, where)) {
+ 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);
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+
if (ret == PCIBIOS_SUCCESSFUL && !bus->number && !devfn &&
(where & 0xffc) == PCI_CLASS_REVISION)
/*
@@ -257,8 +335,14 @@ static void __init cns3xxx_pcie_hw_init(
static int cns3xxx_pcie_abort_handler(unsigned long addr, unsigned int fsr,
struct pt_regs *regs)
{
+#if 0
+/* R14_ABORT = PC+4 for XSCALE but not ARM11MPCORE
+ * ignore imprecise aborts and use PCI-compatible Status register to
+ * determine errors instead
+ */
if (fsr & (1 << 10))
regs->ARM_pc += 4;
+#endif
return 0;
}