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