From: Shivaprasad G Bhat <[email protected]> The IBM Spyre accelerator (PCI ID 1014:06a7) requires a dedicated warm reset method for reliable EEH recovery on pSeries/ppc64 platforms.
FLR alone is insufficient because it does not re-initialize the Spyre firmware state machine. On ppc64 with EEH enabled, pcibios_set_pcie_reset_state() is overridden in arch/powerpc/kernel/eeh.c to drive the platform-level PERST# signal via EEH PE operations, which is the correct mechanism for full device recovery after an EEH event. The reset function is placed in arch/powerpc/platforms/pseries/pci.c where the EEH infrastructure is already present, declared in pseries.h, and registered in the generic pci_dev_reset_methods[] table in drivers/pci/quirks.c under a CONFIG_PPC_PSERIES guard. This reset method is only registered when CONFIG_PPC_PSERIES is enabled, so it is not available on other platforms. Reset sequence: - Assert PERST# via pcie_warm_reset, hold 250 ms - Deassert PERST# via pcie_deassert_reset - Wait 250 ms for PCIe link retrain and device recovery Signed-off-by: Avinash Roy <[email protected]> Signed-off-by: Shivaprasad G Bhat <[email protected]> --- diff --git a/arch/powerpc/platforms/pseries/pci.c b/arch/powerpc/platforms/pseries/pci.c index 84e4ffe957a8..7aa58d57208f 100644 --- a/arch/powerpc/platforms/pseries/pci.c +++ b/arch/powerpc/platforms/pseries/pci.c @@ -11,6 +11,7 @@ #include <linux/kernel.h> #include <linux/pci.h> #include <linux/string.h> +#include <linux/delay.h> #include <asm/eeh.h> #include <asm/pci-bridge.h> @@ -236,6 +237,41 @@ static void fixup_winbond_82c105(struct pci_dev* dev) DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_82C105, fixup_winbond_82c105); +/* + * Reset Spyre adapter using pci_set_pcie_reset_state() + * This is specifically for PPC platforms where EEH (Enhanced Error Handling) + * requires this reset method for proper device recovery. + */ +int reset_spyre(struct pci_dev *dev, bool probe) +{ + int ret; + + if (probe) + return 0; + + /* Assert warm reset */ + ret = pci_set_pcie_reset_state(dev, pcie_warm_reset); + if (ret) { + pci_err(dev, "Failed to assert reset: %d\n", ret); + return ret; + } + + /* Wait for reset to take effect */ + msleep(250); + + /* Deassert reset */ + ret = pci_set_pcie_reset_state(dev, pcie_deassert_reset); + if (ret) { + pci_err(dev, "Failed to deassert reset: %d\n", ret); + return ret; + } + + /* Wait for device to recover */ + msleep(250); + + return 0; +} + static enum pci_bus_speed prop_to_pci_speed(u32 prop) { switch (prop) { diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h index 3968a6970fa8..79c194aeb3c6 100644 --- a/arch/powerpc/platforms/pseries/pseries.h +++ b/arch/powerpc/platforms/pseries/pseries.h @@ -92,6 +92,10 @@ extern struct pci_controller_ops pseries_pci_controller_ops; int pseries_msi_allocate_domains(struct pci_controller *phb); void pseries_msi_free_domains(struct pci_controller *phb); +/* PCI device reset method for Spyre adapter */ +struct pci_dev; +int reset_spyre(struct pci_dev *dev, bool probe); + extern int CMO_PrPSP; extern int CMO_SecPSP; extern unsigned long CMO_PageSize; diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index b09f27f7846f..1b8ab5d9764b 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4237,6 +4237,11 @@ static int reset_hinic_vf_dev(struct pci_dev *pdev, bool probe) return 0; } +#ifdef CONFIG_PPC_PSERIES +/* Defined in arch/powerpc/platforms/pseries/pci.c */ +int reset_spyre(struct pci_dev *dev, bool probe); +#endif + static const struct pci_dev_reset_methods pci_dev_reset_methods[] = { { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82599_SFP_VF, reset_intel_82599_sfp_virtfn }, @@ -4252,6 +4257,10 @@ static const struct pci_dev_reset_methods pci_dev_reset_methods[] = { reset_chelsio_generic_dev }, { PCI_VENDOR_ID_HUAWEI, PCI_DEVICE_ID_HINIC_VF, reset_hinic_vf_dev }, +#ifdef CONFIG_PPC_PSERIES + { PCI_VENDOR_ID_IBM, 0x06a7, + reset_spyre}, +#endif { 0 } };
