From f9726bfd4b14401d294207a70c7c0c4be8a8c6cc Mon Sep 17 00:00:00 2001 From: Daniel J Blueman Date: Fri, 7 Dec 2012 14:24:32 -0700 Subject: [PATCH] x86/PCI: Add NumaChip remote PCI support Add NumaChip-specific PCI access mechanism via MMCONFIG cycles, but preventing access to AMD Northbridges which shouldn't respond. Signed-off-by: Daniel J Blueman Signed-off-by: Bjorn Helgaas --- arch/x86/Kconfig | 1 + arch/x86/include/asm/numachip/numachip.h | 19 +++++ arch/x86/kernel/apic/apic_numachip.c | 2 + arch/x86/pci/Makefile | 1 + arch/x86/pci/numachip.c | 129 +++++++++++++++++++++++++++++++ 5 files changed, 152 insertions(+) create mode 100644 arch/x86/include/asm/numachip/numachip.h create mode 100644 arch/x86/pci/numachip.c diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 46c3bff..17fb8eb 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -374,6 +374,7 @@ config X86_NUMACHIP depends on NUMA depends on SMP depends on X86_X2APIC + depends on PCI_MMCONFIG ---help--- Adds support for Numascale NumaChip large-SMP systems. Needed to enable more than ~168 cores. diff --git a/arch/x86/include/asm/numachip/numachip.h b/arch/x86/include/asm/numachip/numachip.h new file mode 100644 index 0000000..1c6f7f6 --- /dev/null +++ b/arch/x86/include/asm/numachip/numachip.h @@ -0,0 +1,19 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Numascale NumaConnect-specific header file + * + * Copyright (C) 2012 Numascale AS. All rights reserved. + * + * Send feedback to + * + */ + +#ifndef _ASM_X86_NUMACHIP_NUMACHIP_H +#define _ASM_X86_NUMACHIP_NUMACHIP_H + +extern int __init pci_numachip_init(void); + +#endif /* _ASM_X86_NUMACHIP_NUMACHIP_H */ diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c index a65829a..9c2aa89 100644 --- a/arch/x86/kernel/apic/apic_numachip.c +++ b/arch/x86/kernel/apic/apic_numachip.c @@ -22,6 +22,7 @@ #include #include +#include #include #include #include @@ -179,6 +180,7 @@ static int __init numachip_system_init(void) return 0; x86_cpuinit.fixup_cpu_id = fixup_cpu_id; + x86_init.pci.arch_init = pci_numachip_init; map_csrs(); diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile index 3af5a1e..ee0af58 100644 --- a/arch/x86/pci/Makefile +++ b/arch/x86/pci/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_STA2X11) += sta2x11-fixup.o obj-$(CONFIG_X86_VISWS) += visws.o obj-$(CONFIG_X86_NUMAQ) += numaq_32.o +obj-$(CONFIG_X86_NUMACHIP) += numachip.o obj-$(CONFIG_X86_INTEL_MID) += mrst.o diff --git a/arch/x86/pci/numachip.c b/arch/x86/pci/numachip.c new file mode 100644 index 0000000..7307d9d --- /dev/null +++ b/arch/x86/pci/numachip.c @@ -0,0 +1,129 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Numascale NumaConnect-specific PCI code + * + * Copyright (C) 2012 Numascale AS. All rights reserved. + * + * Send feedback to + * + * PCI accessor functions derived from mmconfig_64.c + * + */ + +#include +#include + +static u8 limit __read_mostly; + +static inline char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn) +{ + struct pci_mmcfg_region *cfg = pci_mmconfig_lookup(seg, bus); + + if (cfg && cfg->virt) + return cfg->virt + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12)); + return NULL; +} + +static int pci_mmcfg_read_numachip(unsigned int seg, unsigned int bus, + unsigned int devfn, int reg, int len, u32 *value) +{ + char __iomem *addr; + + /* Why do we have this when nobody checks it. How about a BUG()!? -AK */ + if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) { +err: *value = -1; + return -EINVAL; + } + + /* Ensure AMD Northbridges don't decode reads to other devices */ + if (unlikely(bus == 0 && devfn >= limit)) { + *value = -1; + return 0; + } + + rcu_read_lock(); + addr = pci_dev_base(seg, bus, devfn); + if (!addr) { + rcu_read_unlock(); + goto err; + } + + switch (len) { + case 1: + *value = mmio_config_readb(addr + reg); + break; + case 2: + *value = mmio_config_readw(addr + reg); + break; + case 4: + *value = mmio_config_readl(addr + reg); + break; + } + rcu_read_unlock(); + + return 0; +} + +static int pci_mmcfg_write_numachip(unsigned int seg, unsigned int bus, + unsigned int devfn, int reg, int len, u32 value) +{ + char __iomem *addr; + + /* Why do we have this when nobody checks it. How about a BUG()!? -AK */ + if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) + return -EINVAL; + + /* Ensure AMD Northbridges don't decode writes to other devices */ + if (unlikely(bus == 0 && devfn >= limit)) + return 0; + + rcu_read_lock(); + addr = pci_dev_base(seg, bus, devfn); + if (!addr) { + rcu_read_unlock(); + return -EINVAL; + } + + switch (len) { + case 1: + mmio_config_writeb(addr + reg, value); + break; + case 2: + mmio_config_writew(addr + reg, value); + break; + case 4: + mmio_config_writel(addr + reg, value); + break; + } + rcu_read_unlock(); + + return 0; +} + +const struct pci_raw_ops pci_mmcfg_numachip = { + .read = pci_mmcfg_read_numachip, + .write = pci_mmcfg_write_numachip, +}; + +int __init pci_numachip_init(void) +{ + int ret = 0; + u32 val; + + /* For remote I/O, restrict bus 0 access to the actual number of AMD + Northbridges, which starts at device number 0x18 */ + ret = raw_pci_read(0, 0, PCI_DEVFN(0x18, 0), 0x60, sizeof(val), &val); + if (ret) + goto out; + + /* HyperTransport fabric size in bits 6:4 */ + limit = PCI_DEVFN(0x18 + ((val >> 4) & 7) + 1, 0); + + /* Use NumaChip PCI accessors for non-extended and extended access */ + raw_pci_ops = raw_pci_ext_ops = &pci_mmcfg_numachip; +out: + return ret; +} -- 2.7.4