1 /* 2 * vSMPowered(tm) systems specific initialization 3 * Copyright (C) 2005 ScaleMP Inc. 4 * 5 * Use of this code is subject to the terms and conditions of the 6 * GNU general public license version 2. See "COPYING" or 7 * http://www.gnu.org/licenses/gpl.html 8 * 9 * Ravikiran Thirumalai <kiran@scalemp.com>, 10 * Shai Fultheim <shai@scalemp.com> 11 * Paravirt ops integration: Glauber de Oliveira Costa <gcosta@redhat.com>, 12 * Ravikiran Thirumalai <kiran@scalemp.com> 13 */ 14 15 #include <linux/init.h> 16 #include <linux/pci_ids.h> 17 #include <linux/pci_regs.h> 18 19 #include <asm/apic.h> 20 #include <asm/pci-direct.h> 21 #include <asm/io.h> 22 #include <asm/paravirt.h> 23 #include <asm/setup.h> 24 25 #if defined CONFIG_PCI && defined CONFIG_PARAVIRT 26 /* 27 * Interrupt control on vSMPowered systems: 28 * ~AC is a shadow of IF. If IF is 'on' AC should be 'off' 29 * and vice versa. 30 */ 31 32 static unsigned long vsmp_save_fl(void) 33 { 34 unsigned long flags = native_save_fl(); 35 36 if (!(flags & X86_EFLAGS_IF) || (flags & X86_EFLAGS_AC)) 37 flags &= ~X86_EFLAGS_IF; 38 return flags; 39 } 40 41 static void vsmp_restore_fl(unsigned long flags) 42 { 43 if (flags & X86_EFLAGS_IF) 44 flags &= ~X86_EFLAGS_AC; 45 else 46 flags |= X86_EFLAGS_AC; 47 native_restore_fl(flags); 48 } 49 50 static void vsmp_irq_disable(void) 51 { 52 unsigned long flags = native_save_fl(); 53 54 native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC); 55 } 56 57 static void vsmp_irq_enable(void) 58 { 59 unsigned long flags = native_save_fl(); 60 61 native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC)); 62 } 63 64 static unsigned __init vsmp_patch(u8 type, u16 clobbers, void *ibuf, 65 unsigned long addr, unsigned len) 66 { 67 switch (type) { 68 case PARAVIRT_PATCH(pv_irq_ops.irq_enable): 69 case PARAVIRT_PATCH(pv_irq_ops.irq_disable): 70 case PARAVIRT_PATCH(pv_irq_ops.save_fl): 71 case PARAVIRT_PATCH(pv_irq_ops.restore_fl): 72 return paravirt_patch_default(type, clobbers, ibuf, addr, len); 73 default: 74 return native_patch(type, clobbers, ibuf, addr, len); 75 } 76 77 } 78 79 static void __init set_vsmp_pv_ops(void) 80 { 81 void *address; 82 unsigned int cap, ctl, cfg; 83 84 /* set vSMP magic bits to indicate vSMP capable kernel */ 85 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0); 86 address = early_ioremap(cfg, 8); 87 cap = readl(address); 88 ctl = readl(address + 4); 89 printk(KERN_INFO "vSMP CTL: capabilities:0x%08x control:0x%08x\n", 90 cap, ctl); 91 if (cap & ctl & (1 << 4)) { 92 /* Setup irq ops and turn on vSMP IRQ fastpath handling */ 93 pv_irq_ops.irq_disable = vsmp_irq_disable; 94 pv_irq_ops.irq_enable = vsmp_irq_enable; 95 pv_irq_ops.save_fl = vsmp_save_fl; 96 pv_irq_ops.restore_fl = vsmp_restore_fl; 97 pv_init_ops.patch = vsmp_patch; 98 99 ctl &= ~(1 << 4); 100 writel(ctl, address + 4); 101 ctl = readl(address + 4); 102 printk(KERN_INFO "vSMP CTL: control set to:0x%08x\n", ctl); 103 } 104 105 early_iounmap(address, 8); 106 } 107 #else 108 static void __init set_vsmp_pv_ops(void) 109 { 110 } 111 #endif 112 113 #ifdef CONFIG_PCI 114 static int is_vsmp = -1; 115 116 static void __init detect_vsmp_box(void) 117 { 118 is_vsmp = 0; 119 120 if (!early_pci_allowed()) 121 return; 122 123 /* Check if we are running on a ScaleMP vSMPowered box */ 124 if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) == 125 (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16))) 126 is_vsmp = 1; 127 } 128 129 int is_vsmp_box(void) 130 { 131 if (is_vsmp != -1) 132 return is_vsmp; 133 else { 134 WARN_ON_ONCE(1); 135 return 0; 136 } 137 } 138 #else 139 static void __init detect_vsmp_box(void) 140 { 141 } 142 int is_vsmp_box(void) 143 { 144 return 0; 145 } 146 #endif 147 148 void __init vsmp_init(void) 149 { 150 detect_vsmp_box(); 151 if (!is_vsmp_box()) 152 return; 153 154 set_vsmp_pv_ops(); 155 return; 156 } 157