| Message ID | 20171117185859.2756-1-gpiccoli@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 45baee1416a0086dccaa8a94c70e6721a6906fa2 |
| Headers | show |
| Series | [v3] powerpc/powernv: Add ppc_pci_reset_phbs parameter to issue a PHB reset | expand |
On Fri, 2017-11-17 at 18:58:59 UTC, "Guilherme G. Piccoli" wrote: > During a kdump kernel boot in PowerPC, we request a reset of the PHBs > to the FW. It makes sense, since if we are booting a kdump kernel it > means we had some trouble before and we cannot rely in the adapters' > health; they could be in a bad state, hence the reset is needed. > > But this reset is useful not only in kdump - there are situations, > specially when debugging drivers, that we could break an adapter in > a way it requires such reset. One can tell to just go ahead and > reboot the machine, but happens that many times doing kexec is much > faster, and so preferable than a full power cycle. > > This patch adds the ppc_pci_reset_phbs parameter to perform such reset. > > Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/45baee1416a0086dccaa8a94c70e67 cheers
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index fb5cd7511189..19f1b0021585 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda.c +++ b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -89,6 +89,7 @@ void pe_level_printk(const struct pnv_ioda_pe *pe, const char *level, } static bool pnv_iommu_bypass_disabled __read_mostly; +static bool pci_reset_phbs __read_mostly; static int __init iommu_setup(char *str) { @@ -110,6 +111,14 @@ static int __init iommu_setup(char *str) } early_param("iommu", iommu_setup); +static int __init pci_reset_phbs_setup(char *str) +{ + pci_reset_phbs = true; + return 0; +} + +early_param("ppc_pci_reset_phbs", pci_reset_phbs_setup); + static inline bool pnv_pci_is_m64(struct pnv_phb *phb, struct resource *r) { /* @@ -4014,9 +4023,10 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np, * If we're running in kdump kernel, the previous kernel never * shutdown PCI devices correctly. We already got IODA table * cleaned out. So we have to issue PHB reset to stop all PCI - * transactions from previous kernel. + * transactions from previous kernel. The ppc_pci_reset_phbs + * kernel parameter will force this reset too. */ - if (is_kdump_kernel()) { + if (is_kdump_kernel() || pci_reset_phbs) { pr_info(" Issue PHB reset ...\n"); pnv_eeh_phb_reset(hose, EEH_RESET_FUNDAMENTAL); pnv_eeh_phb_reset(hose, EEH_RESET_DEACTIVATE);
During a kdump kernel boot in PowerPC, we request a reset of the PHBs to the FW. It makes sense, since if we are booting a kdump kernel it means we had some trouble before and we cannot rely in the adapters' health; they could be in a bad state, hence the reset is needed. But this reset is useful not only in kdump - there are situations, specially when debugging drivers, that we could break an adapter in a way it requires such reset. One can tell to just go ahead and reboot the machine, but happens that many times doing kexec is much faster, and so preferable than a full power cycle. This patch adds the ppc_pci_reset_phbs parameter to perform such reset. Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> --- * v3: Changed parameter name, adding prefix "ppc_" [mpe suggestion] arch/powerpc/platforms/powernv/pci-ioda.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)