kernel-aes67/include/asm-sh64/pci.h
David S. Miller e24c2d963a [PATCH] PCI: DMA bursting advice
After seeing, at best, "guesses" as to the following kind
of information in several drivers, I decided that we really
need a way for platforms to specifically give advice in this
area for what works best with their PCI controller implementation.

Basically, this new interface gives DMA bursting advice on
PCI.  There are three forms of the advice:

1) Burst as much as possible, it is not necessary to end bursts
   on some particular boundary for best performance.

2) Burst on some byte count multiple.  A DMA burst to some multiple of
   number of bytes may be done, but it is important to end the burst
   on an exact multiple for best performance.

   The best example of this I am aware of are the PPC64 PCI
   controllers, where if you end a burst mid-cacheline then
   chip has to refetch the data and the IOMMU translations
   which hurts performance a lot.

3) Burst on a single byte count multiple.  Bursts shall end
   exactly on the next multiple boundary for best performance.

   Sparc64 and Alpha's PCI controllers operate this way.  They
   disconnect any device which tries to burst across a cacheline
   boundary.

   Actually, newer sparc64 PCI controllers do not have this behavior.
   That is why the "pdev" is passed into the interface, so I can
   add code later to check which PCI controller the system is using
   and give advice accordingly.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-27 21:52:45 -07:00

119 lines
3.3 KiB
C

#ifndef __ASM_SH64_PCI_H
#define __ASM_SH64_PCI_H
#ifdef __KERNEL__
#include <linux/dma-mapping.h>
/* Can be used to override the logic in pci_scan_bus for skipping
already-configured bus numbers - to be used for buggy BIOSes
or architectures with incomplete PCI setup by the loader */
#define pcibios_assign_all_busses() 1
/*
* These are currently the correct values for the STM overdrive board
* We need some way of setting this on a board specific way, it will
* not be the same on other boards I think
*/
#if defined(CONFIG_CPU_SUBTYPE_SH5_101) || defined(CONFIG_CPU_SUBTYPE_SH5_103)
#define PCIBIOS_MIN_IO 0x2000
#define PCIBIOS_MIN_MEM 0x40000000
#endif
extern void pcibios_set_master(struct pci_dev *dev);
/*
* Set penalize isa irq function
*/
static inline void pcibios_penalize_isa_irq(int irq)
{
/* We don't do dynamic PCI IRQ allocation */
}
/* Dynamic DMA mapping stuff.
* SuperH has everything mapped statically like x86.
*/
/* The PCI address space does equal the physical memory
* address space. The networking and block device layers use
* this boolean for bounce buffer decisions.
*/
#define PCI_DMA_BUS_IS_PHYS (1)
#include <linux/types.h>
#include <linux/slab.h>
#include <asm/scatterlist.h>
#include <linux/string.h>
#include <asm/io.h>
/* pci_unmap_{single,page} being a nop depends upon the
* configuration.
*/
#ifdef CONFIG_SH_PCIDMA_NONCOHERENT
#define DECLARE_PCI_UNMAP_ADDR(ADDR_NAME) \
dma_addr_t ADDR_NAME;
#define DECLARE_PCI_UNMAP_LEN(LEN_NAME) \
__u32 LEN_NAME;
#define pci_unmap_addr(PTR, ADDR_NAME) \
((PTR)->ADDR_NAME)
#define pci_unmap_addr_set(PTR, ADDR_NAME, VAL) \
(((PTR)->ADDR_NAME) = (VAL))
#define pci_unmap_len(PTR, LEN_NAME) \
((PTR)->LEN_NAME)
#define pci_unmap_len_set(PTR, LEN_NAME, VAL) \
(((PTR)->LEN_NAME) = (VAL))
#else
#define DECLARE_PCI_UNMAP_ADDR(ADDR_NAME)
#define DECLARE_PCI_UNMAP_LEN(LEN_NAME)
#define pci_unmap_addr(PTR, ADDR_NAME) (0)
#define pci_unmap_addr_set(PTR, ADDR_NAME, VAL) do { } while (0)
#define pci_unmap_len(PTR, LEN_NAME) (0)
#define pci_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0)
#endif
/* Not supporting more than 32-bit PCI bus addresses now, but
* must satisfy references to this function. Change if needed.
*/
#define pci_dac_dma_supported(pci_dev, mask) (0)
/* These macros should be used after a pci_map_sg call has been done
* to get bus addresses of each of the SG entries and their lengths.
* You should only work with the number of sg entries pci_map_sg
* returns, or alternatively stop on the first sg_dma_len(sg) which
* is 0.
*/
#define sg_dma_address(sg) ((sg)->dma_address)
#define sg_dma_len(sg) ((sg)->length)
static inline void pci_dma_burst_advice(struct pci_dev *pdev,
enum pci_dma_burst_strategy *strat,
unsigned long *strategy_parameter)
{
*strat = PCI_DMA_BURST_INFINITY;
*strategy_parameter = ~0UL;
}
/* Board-specific fixup routines. */
extern void pcibios_fixup(void);
extern void pcibios_fixup_irqs(void);
#ifdef CONFIG_PCI_AUTO
extern int pciauto_assign_resources(int busno, struct pci_channel *hose);
#endif
static inline void pcibios_add_platform_entries(struct pci_dev *dev)
{
}
#endif /* __KERNEL__ */
/* generic pci stuff */
#include <asm-generic/pci.h>
/* generic DMA-mapping stuff */
#include <asm-generic/pci-dma-compat.h>
#endif /* __ASM_SH64_PCI_H */