Initial import

1 files changed, 245 insertions, 0 deletions

diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
new file mode 100644
index 000000000..ee22c1d93
--- /dev/null
+++ b/arch/x86/kernel/vsmp_64.c
@@ -0,0 +1,245 @@
+/*
+ * vSMPowered(tm) systems specific initialization
+ * Copyright (C) 2005 ScaleMP Inc.
+ *
+ * Use of this code is subject to the terms and conditions of the
+ * GNU general public license version 2. See "COPYING" or
+ * http://www.gnu.org/licenses/gpl.html
+ *
+ * Ravikiran Thirumalai <kiran@scalemp.com>,
+ * Shai Fultheim <shai@scalemp.com>
+ * Paravirt ops integration: Glauber de Oliveira Costa <gcosta@redhat.com>,
+ *			     Ravikiran Thirumalai <kiran@scalemp.com>
+ */
+
+#include <linux/init.h>
+#include <linux/pci_ids.h>
+#include <linux/pci_regs.h>
+#include <linux/smp.h>
+#include <linux/irq.h>
+
+#include <asm/apic.h>
+#include <asm/pci-direct.h>
+#include <asm/io.h>
+#include <asm/paravirt.h>
+#include <asm/setup.h>
+
+#define TOPOLOGY_REGISTER_OFFSET 0x10
+
+/* Flag below is initialized once during vSMP PCI initialization. */
+static int irq_routing_comply = 1;
+
+#if defined CONFIG_PCI && defined CONFIG_PARAVIRT
+/*
+ * Interrupt control on vSMPowered systems:
+ * ~AC is a shadow of IF.  If IF is 'on' AC should be 'off'
+ * and vice versa.
+ */
+
+asmlinkage __visible unsigned long vsmp_save_fl(void)
+{
+	unsigned long flags = native_save_fl();
+
+	if (!(flags & X86_EFLAGS_IF) || (flags & X86_EFLAGS_AC))
+		flags &= ~X86_EFLAGS_IF;
+	return flags;
+}
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl);
+
+__visible void vsmp_restore_fl(unsigned long flags)
+{
+	if (flags & X86_EFLAGS_IF)
+		flags &= ~X86_EFLAGS_AC;
+	else
+		flags |= X86_EFLAGS_AC;
+	native_restore_fl(flags);
+}
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl);
+
+asmlinkage __visible void vsmp_irq_disable(void)
+{
+	unsigned long flags = native_save_fl();
+
+	native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
+}
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable);
+
+asmlinkage __visible void vsmp_irq_enable(void)
+{
+	unsigned long flags = native_save_fl();
+
+	native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
+}
+PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_enable);
+
+static unsigned __init_or_module vsmp_patch(u8 type, u16 clobbers, void *ibuf,
+				  unsigned long addr, unsigned len)
+{
+	switch (type) {
+	case PARAVIRT_PATCH(pv_irq_ops.irq_enable):
+	case PARAVIRT_PATCH(pv_irq_ops.irq_disable):
+	case PARAVIRT_PATCH(pv_irq_ops.save_fl):
+	case PARAVIRT_PATCH(pv_irq_ops.restore_fl):
+		return paravirt_patch_default(type, clobbers, ibuf, addr, len);
+	default:
+		return native_patch(type, clobbers, ibuf, addr, len);
+	}
+
+}
+
+static void __init set_vsmp_pv_ops(void)
+{
+	void __iomem *address;
+	unsigned int cap, ctl, cfg;
+
+	/* set vSMP magic bits to indicate vSMP capable kernel */
+	cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0);
+	address = early_ioremap(cfg, 8);
+	cap = readl(address);
+	ctl = readl(address + 4);
+	printk(KERN_INFO "vSMP CTL: capabilities:0x%08x  control:0x%08x\n",
+	       cap, ctl);
+
+	/* If possible, let the vSMP foundation route the interrupt optimally */
+#ifdef CONFIG_SMP
+	if (cap & ctl & BIT(8)) {
+		ctl &= ~BIT(8);
+
+		/* Interrupt routing set to ignore */
+		irq_routing_comply = 0;
+
+#ifdef CONFIG_PROC_FS
+		/* Don't let users change irq affinity via procfs */
+		no_irq_affinity = 1;
+#endif
+	}
+#endif
+
+	if (cap & ctl & (1 << 4)) {
+		/* Setup irq ops and turn on vSMP  IRQ fastpath handling */
+		pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable);
+		pv_irq_ops.irq_enable  = PV_CALLEE_SAVE(vsmp_irq_enable);
+		pv_irq_ops.save_fl  = PV_CALLEE_SAVE(vsmp_save_fl);
+		pv_irq_ops.restore_fl  = PV_CALLEE_SAVE(vsmp_restore_fl);
+		pv_init_ops.patch = vsmp_patch;
+		ctl &= ~(1 << 4);
+	}
+	writel(ctl, address + 4);
+	ctl = readl(address + 4);
+	pr_info("vSMP CTL: control set to:0x%08x\n", ctl);
+
+	early_iounmap(address, 8);
+}
+#else
+static void __init set_vsmp_pv_ops(void)
+{
+}
+#endif
+
+#ifdef CONFIG_PCI
+static int is_vsmp = -1;
+
+static void __init detect_vsmp_box(void)
+{
+	is_vsmp = 0;
+
+	if (!early_pci_allowed())
+		return;
+
+	/* Check if we are running on a ScaleMP vSMPowered box */
+	if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
+	     (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
+		is_vsmp = 1;
+}
+
+static int is_vsmp_box(void)
+{
+	if (is_vsmp != -1)
+		return is_vsmp;
+	else {
+		WARN_ON_ONCE(1);
+		return 0;
+	}
+}
+
+#else
+static void __init detect_vsmp_box(void)
+{
+}
+static 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
+}
+
+static int apicid_phys_pkg_id(int initial_apic_id, int index_msb)
+{
+	return hard_smp_processor_id() >> index_msb;
+}
+
+/*
+ * In vSMP, all cpus should be capable of handling interrupts, regardless of
+ * the APIC used.
+ */
+static void fill_vector_allocation_domain(int cpu, struct cpumask *retmask,
+					  const struct cpumask *mask)
+{
+	cpumask_setall(retmask);
+}
+
+static void vsmp_apic_post_init(void)
+{
+	/* need to update phys_pkg_id */
+	apic->phys_pkg_id = apicid_phys_pkg_id;
+
+	if (!irq_routing_comply)
+		apic->vector_allocation_domain = fill_vector_allocation_domain;
+}
+
+void __init vsmp_init(void)
+{
+	detect_vsmp_box();
+	if (!is_vsmp_box())
+		return;
+
+	x86_platform.apic_post_init = vsmp_apic_post_init;
+
+	vsmp_cap_cpus();
+
+	set_vsmp_pv_ops();
+	return;
+}