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

1 files changed, 40 insertions, 0 deletions

diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
index a1d804bcd483..8eeb55a551b4 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;
 }