 8885b7b637
			
		
	
	
	8885b7b637
	
	
	
		
			
			Most architectures implement this in exactly the same way. Instead of having each architecture duplicate this function, provide a single implementation in the core and make it a weak symbol so that it can be overridden on architectures where it is required. Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
		
			
				
	
	
		
			87 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			87 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *	Low-Level PCI Support for SGI Visual Workstation
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|  *
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|  *	(c) 1999--2000 Martin Mares <mj@ucw.cz>
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/pci.h>
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| #include <linux/init.h>
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| 
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| #include <asm/setup.h>
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| #include <asm/pci_x86.h>
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| #include <asm/visws/cobalt.h>
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| #include <asm/visws/lithium.h>
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| 
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| static int pci_visws_enable_irq(struct pci_dev *dev) { return 0; }
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| static void pci_visws_disable_irq(struct pci_dev *dev) { }
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| 
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| /* int (*pcibios_enable_irq)(struct pci_dev *dev) = &pci_visws_enable_irq; */
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| /* void (*pcibios_disable_irq)(struct pci_dev *dev) = &pci_visws_disable_irq; */
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| 
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| /* void __init pcibios_penalize_isa_irq(int irq, int active) {} */
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| 
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| 
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| unsigned int pci_bus0, pci_bus1;
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| 
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| static int __init visws_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
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| {
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| 	int irq, bus = dev->bus->number;
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| 
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| 	pin--;
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| 
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| 	/* Nothing useful at PIIX4 pin 1 */
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| 	if (bus == pci_bus0 && slot == 4 && pin == 0)
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| 		return -1;
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| 
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| 	/* PIIX4 USB is on Bus 0, Slot 4, Line 3 */
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| 	if (bus == pci_bus0 && slot == 4 && pin == 3) {
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| 		irq = CO_IRQ(CO_APIC_PIIX4_USB);
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| 		goto out;
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| 	}
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| 
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| 	/* First pin spread down 1 APIC entry per slot */
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| 	if (pin == 0) {
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| 		irq = CO_IRQ((bus == pci_bus0 ? CO_APIC_PCIB_BASE0 :
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| 						CO_APIC_PCIA_BASE0) + slot);
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| 		goto out;
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| 	}
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| 
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| 	/* lines 1,2,3 from any slot is shared in this twirly pattern */
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| 	if (bus == pci_bus1) {
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| 		/* lines 1-3 from devices 0 1 rotate over 2 apic entries */
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| 		irq = CO_IRQ(CO_APIC_PCIA_BASE123 + ((slot + (pin - 1)) % 2));
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| 	} else { /* bus == pci_bus0 */
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| 		/* lines 1-3 from devices 0-3 rotate over 3 apic entries */
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| 		if (slot == 0)
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| 			slot = 3; /* same pattern */
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| 		irq = CO_IRQ(CO_APIC_PCIA_BASE123 + ((3 - slot) + (pin - 1) % 3));
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| 	}
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| out:
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| 	printk(KERN_DEBUG "PCI: Bus %d Slot %d Line %d -> IRQ %d\n", bus, slot, pin, irq);
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| 	return irq;
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| }
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| 
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| int __init pci_visws_init(void)
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| {
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| 	pcibios_enable_irq = &pci_visws_enable_irq;
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| 	pcibios_disable_irq = &pci_visws_disable_irq;
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| 
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| 	/* The VISWS supports configuration access type 1 only */
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| 	pci_probe = (pci_probe | PCI_PROBE_CONF1) &
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| 		    ~(PCI_PROBE_BIOS | PCI_PROBE_CONF2);
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| 
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| 	pci_bus0 = li_pcib_read16(LI_PCI_BUSNUM) & 0xff;
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| 	pci_bus1 = li_pcia_read16(LI_PCI_BUSNUM) & 0xff;
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| 
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| 	printk(KERN_INFO "PCI: Lithium bridge A bus: %u, "
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| 		"bridge B (PIIX4) bus: %u\n", pci_bus1, pci_bus0);
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| 
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| 	raw_pci_ops = &pci_direct_conf1;
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| 	pci_scan_bus_with_sysdata(pci_bus0);
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| 	pci_scan_bus_with_sysdata(pci_bus1);
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| 	pci_fixup_irqs(pci_common_swizzle, visws_map_irq);
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| 	pcibios_resource_survey();
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| 	/* Request bus scan */
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| 	return 1;
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| }
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