linux_dsm_epyc7002/arch/i386/kernel/quirks.c

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/*
* This file contains work-arounds for x86 and x86_64 platform bugs.
*/
#include <linux/pci.h>
#include <linux/irq.h>
#include <asm/pci-direct.h>
#include <asm/genapic.h>
#include <asm/cpu.h>
#if defined(CONFIG_X86_IO_APIC) && defined(CONFIG_SMP) && defined(CONFIG_PCI)
static void __devinit verify_quirk_intel_irqbalance(struct pci_dev *dev)
{
u8 config, rev;
u32 word;
/* BIOS may enable hardware IRQ balancing for
* E7520/E7320/E7525(revision ID 0x9 and below)
* based platforms.
* For those platforms, make sure that the genapic is set to 'flat'
*/
pci_read_config_byte(dev, PCI_CLASS_REVISION, &rev);
if (rev > 0x9)
return;
/* enable access to config space*/
pci_read_config_byte(dev, 0xf4, &config);
pci_write_config_byte(dev, 0xf4, config|0x2);
/* read xTPR register */
raw_pci_ops->read(0, 0, 0x40, 0x4c, 2, &word);
if (!(word & (1 << 13))) {
#ifdef CONFIG_X86_64
if (genapic != &apic_flat)
panic("APIC mode must be flat on this system\n");
#elif defined(CONFIG_X86_GENERICARCH)
if (genapic != &apic_default)
panic("APIC mode must be default(flat) on this system. Use apic=default\n");
#endif
}
/* put back the original value for config space*/
if (!(config & 0x2))
pci_write_config_byte(dev, 0xf4, config);
}
void __init quirk_intel_irqbalance(void)
{
u8 config, rev;
u32 word;
/* BIOS may enable hardware IRQ balancing for
* E7520/E7320/E7525(revision ID 0x9 and below)
* based platforms.
* Disable SW irqbalance/affinity on those platforms.
*/
rev = read_pci_config_byte(0, 0, 0, PCI_CLASS_REVISION);
if (rev > 0x9)
return;
printk(KERN_INFO "Intel E7520/7320/7525 detected.");
/* enable access to config space */
config = read_pci_config_byte(0, 0, 0, 0xf4);
write_pci_config_byte(0, 0, 0, 0xf4, config|0x2);
/* read xTPR register */
word = read_pci_config_16(0, 0, 0x40, 0x4c);
if (!(word & (1 << 13))) {
printk(KERN_INFO "Disabling irq balancing and affinity\n");
#ifdef CONFIG_IRQBALANCE
irqbalance_disable("");
#endif
noirqdebug_setup("");
#ifdef CONFIG_PROC_FS
no_irq_affinity = 1;
#endif
#ifdef CONFIG_HOTPLUG_CPU
printk(KERN_INFO "Disabling cpu hotplug control\n");
enable_cpu_hotplug = 0;
#endif
#ifdef CONFIG_X86_64
/* force the genapic selection to flat mode so that
* interrupts can be redirected to more than one CPU.
*/
genapic_force = &apic_flat;
#endif
}
/* put back the original value for config space */
if (!(config & 0x2))
write_pci_config_byte(0, 0, 0, 0xf4, config);
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7320_MCH, verify_quirk_intel_irqbalance);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7525_MCH, verify_quirk_intel_irqbalance);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7520_MCH, verify_quirk_intel_irqbalance);
#endif