File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
new file mode 100644
index 0000000..b034b1b
--- /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 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;
+}