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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-23 18:16:40 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-23 18:16:40 (GMT) |
commit | 44bc40e1489622234169786b0ad5a1f4a01e1090 (patch) | |
tree | cd247a6f130b8993e92ac62f76ced2b023491d09 /arch/x86/kernel | |
parent | 02171b4a7c5b555d08c3321332e0c45776518276 (diff) | |
parent | ead91d4b8c3b1fb08a73aaa4a191230ecf717ee0 (diff) | |
download | linux-44bc40e1489622234169786b0ad5a1f4a01e1090.tar.xz |
Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 platform changes from Ingo Molnar:
"This tree includes assorted platform driver updates and a preparatory
series for a platform with custom DMA remapping semantics (sta2x11 I/O
hub)."
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vsmp: Fix number of CPUs when vsmp is disabled
keyboard: Use BIOS Keyboard variable to set Numlock
x86/olpc/xo1/sci: Report RTC wakeup events
x86/olpc/xo1/sci: Produce wakeup events for buttons and switches
x86, platform: Initial support for sta2x11 I/O hub
x86: Introduce CONFIG_X86_DMA_REMAP
x86-32: Introduce CONFIG_X86_DEV_DMA_OPS
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/vsmp_64.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c index a1d804b..8eeb55a 100644 --- a/arch/x86/kernel/vsmp_64.c +++ b/arch/x86/kernel/vsmp_64.c @@ -15,6 +15,7 @@ #include <linux/init.h> #include <linux/pci_ids.h> #include <linux/pci_regs.h> +#include <linux/smp.h> #include <asm/apic.h> #include <asm/pci-direct.h> @@ -22,6 +23,8 @@ #include <asm/paravirt.h> #include <asm/setup.h> +#define TOPOLOGY_REGISTER_OFFSET 0x10 + #if defined CONFIG_PCI && defined CONFIG_PARAVIRT /* * Interrupt control on vSMPowered systems: @@ -149,12 +152,49 @@ int is_vsmp_box(void) return 0; } #endif + +static void __init vsmp_cap_cpus(void) +{ +#if !defined(CONFIG_X86_VSMP) && defined(CONFIG_SMP) + void __iomem *address; + unsigned int cfg, topology, node_shift, maxcpus; + + /* + * CONFIG_X86_VSMP is not configured, so limit the number CPUs to the + * ones present in the first board, unless explicitly overridden by + * setup_max_cpus + */ + if (setup_max_cpus != NR_CPUS) + return; + + /* Read the vSMP Foundation topology register */ + cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0); + address = early_ioremap(cfg + TOPOLOGY_REGISTER_OFFSET, 4); + if (WARN_ON(!address)) + return; + + topology = readl(address); + node_shift = (topology >> 16) & 0x7; + if (!node_shift) + /* The value 0 should be decoded as 8 */ + node_shift = 8; + maxcpus = (topology & ((1 << node_shift) - 1)) + 1; + + pr_info("vSMP CTL: Capping CPUs to %d (CONFIG_X86_VSMP is unset)\n", + maxcpus); + setup_max_cpus = maxcpus; + early_iounmap(address, 4); +#endif +} + void __init vsmp_init(void) { detect_vsmp_box(); if (!is_vsmp_box()) return; + vsmp_cap_cpus(); + set_vsmp_pv_ops(); return; } |