[LinuxBIOS] Enabling APIC 82801xx

joe at smittys.pointclark.net joe at smittys.pointclark.net
Fri Sep 28 08:40:00 CEST 2007


OK, I have a new booting problem. LB dies on the  
i82801xx_enable_ioapic() function in 82801xx_lpc.c:


void i82801xx_enable_ioapic(struct device *dev)
{
	uint32_t reg32;
	volatile uint32_t *ioapic_index = (volatile uint32_t *)0xfec00000;
	volatile uint32_t *ioapic_data = (volatile uint32_t *)0xfec00010;

	reg32 = pci_read_config32(dev, GEN_CNTL);
	reg32 |= (3 << 7);	/* Enable IOAPIC */
	reg32 |= (1 << 13);	/* Coprocessor error enable */
	reg32 |= (1 << 1);	/* Delayed transaction enable */
	reg32 |= (1 << 2);	/* DMA collection buffer enable */
	pci_write_config32(dev, GEN_CNTL, reg32);
	printk_debug("IOAPIC Southbridge enabled %x\n", reg32);

	*ioapic_index = 0;
	*ioapic_data = (1 << 25);

	*ioapic_index = 0;
	reg32 = *ioapic_data;
	printk_debug("Southbridge APIC ID = %x\n", reg32);
	if (reg32 != (1 << 25))
		die("APIC Error\n");

	/* TODO: From i82801ca, needed/useful on other ICH? */
	*ioapic_index = 3;	// Select Boot Configuration register
	*ioapic_data = 1;	// Use Processor System Bus to deliver interrupts
}

Initializing devices...
Root Device init
PCI: 00:00.0 init
Northbridge init
PCI: 00:1d.0 init
PCI: 00:1d.1 init
PCI: 00:1d.2 init
PCI: 00:1d.7 init
EHCI: Setting up controller.. done.
PCI: 00:1e.0 init
PCI: 00:1f.0 init
IOAPIC Southbridge enabled 2186
Southbridge APIC ID = 0
APIC Error

What is going on here? Why is *ioapic_data coming back as 0x0 after it  
has been set to 0x2000000 (1 << 25)? Help?


Thanks - Joe




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