Re: [PATCH V3 3/4] PCI: Add support for non-BAR ROMs

[Don Dutile <ddutile@redhat.com>]

On 08/23/2012 12:36 PM, Matthew Garrett wrote:
> Platforms may provide their own mechanisms for obtaining ROMs. Add support
> for using data provided by the platform in that case.
>
> Signed-off-by: Matthew Garrett<mjg@redhat.com>
> ---
>   drivers/pci/rom.c   | 11 +++++++++--
>   include/linux/pci.h |  2 ++
>   2 files changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c
> index 48ebdb2..46026e4 100644
> --- a/drivers/pci/rom.c
> +++ b/drivers/pci/rom.c
> @@ -118,11 +118,17 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
>   	void __iomem *rom;
>
>   	/*
> +	 * Some devices may provide ROMs via a source other than the BAR
> +	 */
> +	if (pdev->rom&&  pdev->romlen) {
> +		*size = pdev->romlen;
> +		return phys_to_virt((phys_addr_t)pdev->rom);
                        ^^^^^
                          ioremap_nocache() ? ... or is caching rom ok?

> +	/*
>   	 * IORESOURCE_ROM_SHADOW set on x86, x86_64 and IA64 supports legacy
>   	 * memory map if the VGA enable bit of the Bridge Control register is
>   	 * set for embedded VGA.
>   	 */
> -	if (res->flags&  IORESOURCE_ROM_SHADOW) {
> +	} else if (res->flags&  IORESOURCE_ROM_SHADOW) {
>   		/* primary video rom always starts here */
>   		start = (loff_t)0xC0000;
>   		*size = 0x20000; /* cover C000:0 through E000:0 */
> @@ -219,7 +225,8 @@ void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom)
>   	if (res->flags&  (IORESOURCE_ROM_COPY | IORESOURCE_ROM_BIOS_COPY))
>   		return;
>
> -	iounmap(rom);
> +	if (!pdev->rom || !pdev->romlen)
> +		iounmap(rom);
>
>   	/* Disable again before continuing, leave enabled if pci=rom */
>   	if (!(res->flags&  (IORESOURCE_ROM_ENABLE | IORESOURCE_ROM_SHADOW)))
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 6a2625c..2668bb9 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -355,6 +355,8 @@ struct pci_dev {
>   	};
>   	struct pci_ats	*ats;	/* Address Translation Service */
>   #endif
> +	void *rom; /* Physical pointer to ROM if it's not from the BAR */
> +	size_t romlen; /* Length of ROM if it's not from the BAR */
>   };
>
>   static inline struct pci_dev *pci_physfn(struct pci_dev *dev)