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 PV_CALLEE_SAVE_REGS_THUNK(vsmp_save_fl); 41 42 static void vsmp_restore_fl(unsigned long flags) 43 { 44 if (flags & X86_EFLAGS_IF) 45 flags &= ~X86_EFLAGS_AC; 46 else 47 flags |= X86_EFLAGS_AC; 48 native_restore_fl(flags); 49 } 50 PV_CALLEE_SAVE_REGS_THUNK(vsmp_restore_fl); 51 52 static void vsmp_irq_disable(void) 53 { 54 unsigned long flags = native_save_fl(); 55 56 native_restore_fl((flags & ~X86_EFLAGS_IF) | X86_EFLAGS_AC); 57 } 58 PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_disable); 59 60 static void vsmp_irq_enable(void) 61 { 62 unsigned long flags = native_save_fl(); 63 64 native_restore_fl((flags | X86_EFLAGS_IF) & (~X86_EFLAGS_AC)); 65 } 66 PV_CALLEE_SAVE_REGS_THUNK(vsmp_irq_enable); 67 68 static unsigned __init_or_module vsmp_patch(u8 type, u16 clobbers, void *ibuf, 69 unsigned long addr, unsigned len) 70 { 71 switch (type) { 72 case PARAVIRT_PATCH(pv_irq_ops.irq_enable): 73 case PARAVIRT_PATCH(pv_irq_ops.irq_disable): 74 case PARAVIRT_PATCH(pv_irq_ops.save_fl): 75 case PARAVIRT_PATCH(pv_irq_ops.restore_fl): 76 return paravirt_patch_default(type, clobbers, ibuf, addr, len); 77 default: 78 return native_patch(type, clobbers, ibuf, addr, len); 79 } 80 81 } 82 83 static void __init set_vsmp_pv_ops(void) 84 { 85 void __iomem *address; 86 unsigned int cap, ctl, cfg; 87 88 /* set vSMP magic bits to indicate vSMP capable kernel */ 89 cfg = read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0); 90 address = early_ioremap(cfg, 8); 91 cap = readl(address); 92 ctl = readl(address + 4); 93 printk(KERN_INFO "vSMP CTL: capabilities:0x%08x control:0x%08x\n", 94 cap, ctl); 95 if (cap & ctl & (1 << 4)) { 96 /* Setup irq ops and turn on vSMP IRQ fastpath handling */ 97 pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable); 98 pv_irq_ops.irq_enable = PV_CALLEE_SAVE(vsmp_irq_enable); 99 pv_irq_ops.save_fl = PV_CALLEE_SAVE(vsmp_save_fl); 100 pv_irq_ops.restore_fl = PV_CALLEE_SAVE(vsmp_restore_fl); 101 pv_init_ops.patch = vsmp_patch; 102 103 ctl &= ~(1 << 4); 104 writel(ctl, address + 4); 105 ctl = readl(address + 4); 106 printk(KERN_INFO "vSMP CTL: control set to:0x%08x\n", ctl); 107 } 108 109 early_iounmap(address, 8); 110 } 111 #else 112 static void __init set_vsmp_pv_ops(void) 113 { 114 } 115 #endif 116 117 #ifdef CONFIG_PCI 118 static int is_vsmp = -1; 119 120 static void __init detect_vsmp_box(void) 121 { 122 is_vsmp = 0; 123 124 if (!early_pci_allowed()) 125 return; 126 127 /* Check if we are running on a ScaleMP vSMPowered box */ 128 if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) == 129 (PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16))) 130 is_vsmp = 1; 131 } 132 133 int is_vsmp_box(void) 134 { 135 if (is_vsmp != -1) 136 return is_vsmp; 137 else { 138 WARN_ON_ONCE(1); 139 return 0; 140 } 141 } 142 143 #else 144 static void __init detect_vsmp_box(void) 145 { 146 } 147 int is_vsmp_box(void) 148 { 149 return 0; 150 } 151 #endif 152 void __init vsmp_init(void) 153 { 154 detect_vsmp_box(); 155 if (!is_vsmp_box()) 156 return; 157 158 set_vsmp_pv_ops(); 159 return; 160 } 161