[PATCH v3 21/30] ARM: Add fixed PCI i/o mapping

[Nicolas Pitre]

On Thu, 1 Mar 2012, Rob Herring wrote:

> From: Rob Herring <rob.herring at calxeda.com>
> 
> This adds a fixed virtual mapping for PCI i/o addresses. The mapping is
> located at the last 1MB of vmalloc region (0xfef00000).

Please also document this in Documentation/arm/memory.txt.

> Signed-off-by: Rob Herring <rob.herring at calxeda.com>
> Cc: Russell King <linux at arm.linux.org.uk>

With the above comment addressed:

Acked-by: Nicolas Pitre <nico at linaro.org>

> ---
>  arch/arm/include/asm/io.h       |    5 +++++
>  arch/arm/include/asm/mach/pci.h |   18 ++++++++++++++++++
>  arch/arm/kernel/bios32.c        |   23 +++++++++++++++++++++++
>  3 files changed, 46 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
> index d7861b9..5a01930 100644
> --- a/arch/arm/include/asm/io.h
> +++ b/arch/arm/include/asm/io.h
> @@ -106,11 +106,16 @@ static inline void __iomem *__typesafe_io(unsigned long addr)
>  #define __iowmb()		do { } while (0)
>  #endif
>  
> +#define PCI_IO_VIRT_BASE	0xfef00000
> +
>  /*
>   * Now, pick up the machine-defined IO definitions
>   */
>  #ifdef CONFIG_NEED_MACH_IO_H
>  #include <mach/io.h>
> +#elif defined(CONFIG_PCI)
> +#define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
> +#define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
>  #else
>  #define __io(a)		({ (void)(a); __typesafe_io(0); })
>  #endif
> diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
> index d943b7d..6d326d7 100644
> --- a/arch/arm/include/asm/mach/pci.h
> +++ b/arch/arm/include/asm/mach/pci.h
> @@ -60,6 +60,24 @@ struct pci_sys_data {
>  void pci_common_init(struct hw_pci *);
>  
>  /*
> + * Setup fixed I/O mapping. Must be called from .map_io function.
> + */
> +#ifdef CONFIG_PCI
> +extern void pci_map_io_pfn(unsigned long pfn[], int nr);
> +#else
> +static inline void pci_map_io_pfn(unsigned long pfn[], int nr) {}
> +#endif
> +static inline void __init pci_map_io_single_pfn(unsigned long pfn)
> +{
> +	pci_map_io_pfn(&pfn, 1);
> +}
> +
> +static inline void __init pci_map_io_single(unsigned long paddr)
> +{
> +	pci_map_io_single_pfn(__phys_to_pfn(paddr));
> +}
> +
> +/*
>   * PCI controllers
>   */
>  extern int iop3xx_pci_setup(int nr, struct pci_sys_data *);
> diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
> index f58ba35..199f383 100644
> --- a/arch/arm/kernel/bios32.c
> +++ b/arch/arm/kernel/bios32.c
> @@ -13,6 +13,7 @@
>  #include <linux/io.h>
>  
>  #include <asm/mach-types.h>
> +#include <asm/mach/map.h>
>  #include <asm/mach/pci.h>
>  
>  static int debug_pci;
> @@ -674,3 +675,25 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
>  
>  	return 0;
>  }
> +
> +static struct map_desc pci_io_desc __initdata = {
> +	.virtual	= PCI_IO_VIRT_BASE,
> +	.length		= SZ_1M,
> +	.type		= MT_DEVICE,
> +};
> +
> +void __init pci_map_io_pfn(unsigned long pfn[], int nr)
> +{
> +	int i;
> +
> +	if (nr > 1)
> +		pci_io_desc.length = SZ_64K;
> +
> +	for (i = 0; i < nr; i++) {
> +		pci_io_desc.pfn = pfn[i];
> +		iotable_init(&pci_io_desc, 1);
> +
> +		pci_io_desc.virtual += SZ_64K;
> +	}
> +}
> +
> -- 
> 1.7.5.4
>