diff options
Diffstat (limited to 'kernel/arch/x86/pci/numachip.c')
-rw-r--r-- | kernel/arch/x86/pci/numachip.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/kernel/arch/x86/pci/numachip.c b/kernel/arch/x86/pci/numachip.c new file mode 100644 index 000000000..2e565e65c --- /dev/null +++ b/kernel/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 <support@numascale.com> + * + * PCI accessor functions derived from mmconfig_64.c + * + */ + +#include <linux/pci.h> +#include <asm/pci_x86.h> + +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; +} + +static 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; +} |