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[POWERPC] Define pci_unmap_addr() et al. when CONFIG_NOT_COHERENT_CACHE=y

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The current PowerPC code makes pci_unmap_addr(), pci_unmap_addr_set(),
and friends trivial for all 32-bit kernels.  This is reasonable, since
for those kernels it is true that pci_unmap_single() does not need the
DMA address from the original DMA mapping -- in fact, it is a NOP.

However, I recently tried the tg3 driver on a PowerPC 440SPe machine,
which runs a 32-bit kernel and has non-cache-coherent PCI DMA.  I
found that the tg3 driver crashed in pci_dma_sync_single_for_cpu(),
since for non-coherent systems, that function must invalidate the
cache for the DMA address range requested, and therefore it does use
the address passed in.  tg3 uses a DMA address it stashes away with
pci_unmap_addr_set() and retrieves with pci_unmap_addr().  Of course,
since pci_unmap_addr() is defined to (0) right now, this doesn't work.

It seems to me that the tg3 driver is using pci_unmap_addr() in a
legitimate way -- I wouldn't want to have to teach all drivers that
they should use pci_unmap_addr() if they only need the address for
unmapping functions, but if they want the pci_dma_sync functions, then
they have to store the DMA address without the helper macros.
The right fix therefore seems to be in the definition of the macros in
<asm/pci.h> -- we should use the trivial versions only for 32-bit
kernels for coherent systems, and the real versions for both 64-bit
kernels and non-coherent systems.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Roland Dreier 2006-12-06 15:15:38 -08:00 committed by Paul Mackerras
parent 885ed0fb48
commit 1d4454e7ce
2 changed files with 45 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
include/asm-powerpc/pci.h
View File

@ -143,8 +143,13 @@ int pci_mmap_page_range(struct pci_dev *pdev, struct vm_area_struct *vma,
/* Tell drivers/pci/proc.c that we have pci_mmap_page_range() */
#define HAVE_PCI_MMAP 1
#ifdef CONFIG_PPC64
/* pci_unmap_{single,page} is not a nop, thus... */
#if defined(CONFIG_PPC64) || defined(CONFIG_NOT_COHERENT_CACHE)
/*
* For 64-bit kernels, pci_unmap_{single,page} is not a nop.
* For 32-bit non-coherent kernels, pci_dma_sync_single_for_cpu() and
* so on are not nops.
* and thus...
*/
#define DECLARE_PCI_UNMAP_ADDR(ADDR_NAME) \
dma_addr_t ADDR_NAME;
#define DECLARE_PCI_UNMAP_LEN(LEN_NAME) \
@ -158,6 +163,20 @@ int pci_mmap_page_range(struct pci_dev *pdev, struct vm_area_struct *vma,
#define pci_unmap_len_set(PTR, LEN_NAME, VAL) \
(((PTR)->LEN_NAME) = (VAL))
#else /* 32-bit && coherent */
/* pci_unmap_{page,single} is a nop so... */
#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 /* CONFIG_PPC64 || CONFIG_NOT_COHERENT_CACHE */
#ifdef CONFIG_PPC64
/* The PCI address space does not equal the physical memory address
* space (we have an IOMMU). The IDE and SCSI device layers use
* this boolean for bounce buffer decisions.
@ -172,16 +191,8 @@ int pci_mmap_page_range(struct pci_dev *pdev, struct vm_area_struct *vma,
*/
#define PCI_DMA_BUS_IS_PHYS (1)
/* pci_unmap_{page,single} is a nop so... */
#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 /* CONFIG_PPC64 */
extern void pcibios_resource_to_bus(struct pci_dev *dev,
struct pci_bus_region *region,
struct resource *res);

23
include/asm-ppc/pci.h
View File

@ -61,6 +61,27 @@ extern unsigned long pci_bus_to_phys(unsigned int ba, int busnr);
*/
#define PCI_DMA_BUS_IS_PHYS (1)
#ifdef CONFIG_NOT_COHERENT_CACHE
/*
* pci_unmap_{page,single} are NOPs but pci_dma_sync_single_for_cpu()
* and so on are not, so...
*/
#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 /* coherent */
/* pci_unmap_{page,single} is a nop so... */
#define DECLARE_PCI_UNMAP_ADDR(ADDR_NAME)
#define DECLARE_PCI_UNMAP_LEN(LEN_NAME)
@ -69,6 +90,8 @@ extern unsigned long pci_bus_to_phys(unsigned int ba, int busnr);
#define pci_unmap_len(PTR, LEN_NAME) (0)
#define pci_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0)
#endif /* CONFIG_NOT_COHERENT_CACHE */
#ifdef CONFIG_PCI
static inline void pci_dma_burst_advice(struct pci_dev *pdev,
enum pci_dma_burst_strategy *strat,