arch/alpha/kernel/pci_impl.h

Source file repositories/reference/linux-study-clean/arch/alpha/kernel/pci_impl.h

File Facts

System
Linux kernel
Corpus path
arch/alpha/kernel/pci_impl.h
Extension
.h
Size
6398 bytes
Lines
194
Domain
Architecture Layer
Bucket
arch/alpha
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct pci_dev;
struct pci_controller;
struct pci_iommu_arena;

/*
 * We can't just blindly use 64K for machines with EISA busses; they
 * may also have PCI-PCI bridges present, and then we'd configure the
 * bridge incorrectly.
 *
 * Also, we start at 0x8000 or 0x9000, in hopes to get all devices'
 * IO space areas allocated *before* 0xC000; this is because certain
 * BIOSes (Millennium for one) use PCI Config space "mechanism #2"
 * accesses to probe the bus. If a device's registers appear at 0xC000,
 * it may see an INx/OUTx at that address during BIOS emulation of the
 * VGA BIOS, and some cards, notably Adaptec 2940UW, take mortal offense.
 */

#define EISA_DEFAULT_IO_BASE	0x9000	/* start above 8th slot */
#define DEFAULT_IO_BASE		0x8000	/* start at 8th slot */

/*
 * We try to make the DEFAULT_MEM_BASE addresses *always* have more than
 * a single bit set. This is so that devices like the broken Myrinet card
 * will always have a PCI memory address that will never match a IDSEL
 * address in PCI Config space, which can cause problems with early rev cards.
 */

/*
 * An XL is AVANTI (APECS) family, *but* it has only 27 bits of ISA address
 * that get passed through the PCI<->ISA bridge chip. Although this causes
 * us to set the PCI->Mem window bases lower than normal, we still allocate
 * PCI bus devices' memory addresses *below* the low DMA mapping window,
 * and hope they fit below 64Mb (to avoid conflicts), and so that they can
 * be accessed via SPARSE space.
 *
 * We accept the risk that a broken Myrinet card will be put into a true XL
 * and thus can more easily run into the problem described below.
 */
#define XL_DEFAULT_MEM_BASE ((16+2)*1024*1024) /* 16M to 64M-1 is avail */

/*
 * APECS and LCA have only 34 bits for physical addresses, thus limiting PCI
 * bus memory addresses for SPARSE access to be less than 128Mb.
 */
#define APECS_AND_LCA_DEFAULT_MEM_BASE ((16+2)*1024*1024)

/*
 * Because MCPCIA and T2 core logic support more bits for
 * physical addresses, they should allow an expanded range of SPARSE
 * memory addresses.  However, we do not use them all, in order to
 * avoid the HAE manipulation that would be needed.
 */
#define MCPCIA_DEFAULT_MEM_BASE ((32+2)*1024*1024)
#define T2_DEFAULT_MEM_BASE ((16+1)*1024*1024)

/*
 * Because CIA and PYXIS have more bits for physical addresses,
 * they support an expanded range of SPARSE memory addresses.
 */
#define DEFAULT_MEM_BASE ((128+16)*1024*1024)

/* ??? Experimenting with no HAE for CIA.  */
#define CIA_DEFAULT_MEM_BASE ((32+2)*1024*1024)

#define IRONGATE_DEFAULT_MEM_BASE ((256*8-16)*1024*1024)

#define DEFAULT_AGP_APER_SIZE	(64*1024*1024)

/* 
 * A small note about bridges and interrupts.  The DECchip 21050 (and
 * later) adheres to the PCI-PCI bridge specification.  This says that
 * the interrupts on the other side of a bridge are swizzled in the
 * following manner:
 *
 * Dev    Interrupt   Interrupt 
 *        Pin on      Pin on 
 *        Device      Connector
 *
 *   4    A           A
 *        B           B
 *        C           C
 *        D           D
 * 
 *   5    A           B
 *        B           C
 *        C           D
 *        D           A
 *
 *   6    A           C
 *        B           D

Annotation

Implementation Notes