root/arch/x86/kernel/vsmp_64.c

DEFINITIONS

1. vsmp_save_fl
2. vsmp_restore_fl
3. vsmp_irq_disable
4. vsmp_irq_enable
5. vsmp_patch
6. set_vsmp_pv_ops
7. set_vsmp_pv_ops
8. detect_vsmp_box
9. is_vsmp_box
10. detect_vsmp_box
11. is_vsmp_box
12. vsmp_init

/*
 * 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 <asm/apic.h>
#include <asm/pci-direct.h>
#include <asm/io.h>
#include <asm/paravirt.h>
#include <asm/setup.h>

#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.
 */

static 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;
}

static 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);
}

static void vsmp_irq_disable(void)
{
        unsigned long flags = native_save_fl();

        native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC);
}

static void vsmp_irq_enable(void)
{
        unsigned long flags = native_save_fl();

        native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC));
}

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 *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 (cap & ctl & (1 << 4)) {
                /* Setup irq ops and turn on vSMP  IRQ fastpath handling */
                pv_irq_ops.irq_disable = vsmp_irq_disable;
                pv_irq_ops.irq_enable  = vsmp_irq_enable;
                pv_irq_ops.save_fl  = vsmp_save_fl;
                pv_irq_ops.restore_fl  = vsmp_restore_fl;
                pv_init_ops.patch = vsmp_patch;

                ctl &= ~(1 << 4);
                writel(ctl, address + 4);
                ctl = readl(address + 4);
                printk(KERN_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;
}

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)
{
}
int is_vsmp_box(void)
{
        return 0;
}
#endif

void __init vsmp_init(void)
{
        detect_vsmp_box();
        if (!is_vsmp_box())
                return;

        set_vsmp_pv_ops();
        return;
}