[PATCH -v2] x86, k8 nb: Enable k8_northbridges unconditionally on AMD
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From: Borislav Petkov on 12 Mar 2010 09:50 From: Ingo Molnar <mingo(a)elte.hu> Date: Thu, Mar 11, 2010 at 02:22:02PM +0100 > alas, your patch doesnt always build: > > drivers/built-in.o: In function `agp_amd64_probe': > amd64-agp.c:(.devinit.text+0x81d2): undefined reference to `cache_k8_northbridges' > amd64-agp.c:(.devinit.text+0x8207): undefined reference to `k8_northbridges' > amd64-agp.c:(.devinit.text+0x8409): undefined reference to `num_k8_northbridges' > amd64-agp.c:(.devinit.text+0x8500): undefined reference to `k8_northbridges' Ok, this is because this patch inverts dependencies and I need AGP_AMD64 and GART_IOMMU to depend explicitly on K8_NB, which is the more natural thing to do. Here's a better version, it survived a couple of hundred randconfig builds last night: -- From: Borislav Petkov <borislav.petkov(a)amd.com> Date: Mon, 8 Mar 2010 14:27:01 +0100 Subject: [PATCH -v2] x86, k8 nb: Enable k8_northbridges unconditionally on AMD de957628ce7c84764ff41331111036b3ae5bad0f changed setting of the x86_init.iommu.iommu_init function ptr only when GART IOMMU is found. One side effect of it is that num_k8_northbridges is not initialized anymore if not explicitly called. This resulted in uninitialized pointers in <arch/x86/kernel/cpu/intel_cacheinfo.c:amd_calc_l3_indices()>, for example, which uses the num_k8_northbridges thing through node_to_k8_nb_misc(). Fix that through an initcall that runs right after the PCI subsystem and does all the scanning. Then, remove initialization in gart_iommu_init() which is a rootfs_initcall and we're running before that. What is more, since num_k8_northbridges is being used in other places beside GART IOMMU, include it whenever we add AMD CPU support. The previous dependency chain in kconfig contained K8_NB depends on AGP_AMD64|GART_IOMMU which was clearly incorrect. The more natural way in terms of hardware dependency should be AGP_AMD64|GART_IOMMU depends on K8_NB depends on CPU_SUP_AMD && PCI. Make it so Number One! Signed-off-by: Borislav Petkov <borislav.petkov(a)amd.com> Tested-by: Joerg Roedel <joerg.roedel(a)amd.com> --- arch/x86/Kconfig | 4 ++-- arch/x86/kernel/k8.c | 14 ++++++++++++++ arch/x86/kernel/pci-gart_64.c | 2 +- drivers/char/agp/Kconfig | 2 +- 4 files changed, 18 insertions(+), 4 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index e984403..736b1b6 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -659,7 +659,7 @@ config GART_IOMMU bool "GART IOMMU support" if EMBEDDED default y select SWIOTLB - depends on X86_64 && PCI + depends on X86_64 && PCI && K8_NB ---help--- Support for full DMA access of devices with 32bit memory access only on systems with more than 3GB. This is usually needed for USB, @@ -2058,7 +2058,7 @@ endif # X86_32 config K8_NB def_bool y - depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) + depends on CPU_SUP_AMD && PCI source "drivers/pcmcia/Kconfig" diff --git a/arch/x86/kernel/k8.c b/arch/x86/kernel/k8.c index cbc4332..9b89546 100644 --- a/arch/x86/kernel/k8.c +++ b/arch/x86/kernel/k8.c @@ -121,3 +121,17 @@ void k8_flush_garts(void) } EXPORT_SYMBOL_GPL(k8_flush_garts); +static __init int init_k8_nbs(void) +{ + int err = 0; + + err = cache_k8_northbridges(); + + if (err < 0) + printk(KERN_NOTICE "K8 NB: Cannot enumerate AMD northbridges.\n"); + + return err; +} + +/* This has to go after the PCI subsystem */ +fs_initcall(init_k8_nbs); diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c index 34de53b..f3af115 100644 --- a/arch/x86/kernel/pci-gart_64.c +++ b/arch/x86/kernel/pci-gart_64.c @@ -735,7 +735,7 @@ int __init gart_iommu_init(void) unsigned long scratch; long i; - if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0) + if (num_k8_northbridges == 0) return 0; #ifndef CONFIG_AGP_AMD64 diff --git a/drivers/char/agp/Kconfig b/drivers/char/agp/Kconfig index 2fb3a48..4b66c69 100644 --- a/drivers/char/agp/Kconfig +++ b/drivers/char/agp/Kconfig @@ -57,7 +57,7 @@ config AGP_AMD config AGP_AMD64 tristate "AMD Opteron/Athlon64 on-CPU GART support" - depends on AGP && X86 + depends on AGP && X86 && K8_NB help This option gives you AGP support for the GLX component of X using the on-CPU northbridge of the AMD Athlon64/Opteron CPUs. -- 1.7.0.2 -- Regards/Gruss, Boris. - Advanced Micro Devices, Inc. Operating Systems Research Center -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |