From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Yinghai Lu To: Jesse Barnes Cc: Ram Pai , Dominik Brodowski , Linus Torvalds , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Yinghai Lu Subject: [PATCH 7/7] PCI: only enable pci realloc when SRIOV bar is not assigned Date: Fri, 10 Feb 2012 15:33:52 -0800 Message-Id: <1328916832-6588-8-git-send-email-yinghai@kernel.org> In-Reply-To: <1328916832-6588-1-git-send-email-yinghai@kernel.org> References: <1328916832-6588-1-git-send-email-yinghai@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: If bios does not assign those BAR or wrong address, then kernel will try to do pci realloc. in that case, user still can use pci=realloc=off to override it. -v2: According to Jesse, adding one CONFIG option for distribution to disable it or enable it. Signed-off-by: Yinghai Lu --- drivers/pci/Kconfig | 10 ++++++++++ drivers/pci/setup-bus.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 38 insertions(+), 0 deletions(-) diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 37856f7..ee29565 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -31,6 +31,16 @@ config PCI_DEBUG When in doubt, say N. +config PCI_REALLOC_ENABLE_DETECT + bool "PCI Realloc Enable Detecting" + depends on PCI + help + Say Y here if you want the PCI core to detect if pci realloc + need to be enabled. You can always use pci=realloc=on or + pci=realloc=off to override it. + + When in doubt, say N. + config PCI_STUB tristate "PCI Stub driver" depends on PCI diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index c73244a..3aef181 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1293,6 +1293,31 @@ static bool __init pci_realloc_enabled(void) return pci_realloc_enable >= enable_yes_user; } +static void __init pci_realloc_detect(void) +{ +#if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_DETECT) + struct pci_dev *dev = NULL; + + if (pci_realloc_enable != enable_not_set) + return; + + for_each_pci_dev(dev) { + int i; + + for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) { + struct resource *r = &dev->resource[i]; + + /* Not assigned, or rejected by kernel ? */ + if (r->flags && !r->start) { + pci_realloc_enable = enable_yes_detected; + + return; + } + } + } +#endif +} + /* * first try will not touch pci bridge res * second and later try will clear small leaf bridge res @@ -1314,6 +1339,7 @@ pci_assign_unassigned_resources(void) int pci_try_num = 1; /* don't realloc if asked to do so */ + pci_realloc_detect(); if (pci_realloc_enabled()) { int max_depth = pci_get_max_depth(); @@ -1348,6 +1374,8 @@ again: if (tried_times >= pci_try_num) { if (pci_realloc_enable == enable_not_set) printk(KERN_INFO "Some PCI device resources are unassigned, try booting with pci=realloc\n"); + else if (pci_realloc_enable == enable_yes_detected) + printk(KERN_INFO "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n"); free_list(&fail_head); goto enable_and_dump; -- 1.7.7