Re: [Qemu-devel] [PATCH v2] qemu-kvm/pci-assign: 64 bits bar emulation

[Alex Williamson <alex.williamson@redhat.com>]

On Wed, 2012-12-19 at 16:47 +0800, Xudong Hao wrote:
> Enable 64 bits bar emulation.
> 
> v2 changes from v1:
> - Change 0lx% to 0x%016 when print a 64 bit variable.
> 
> Test pass with the current seabios which already support 64bit pci bars.
> 
> Signed-off-by: Xudong Hao <xudong.hao@intel.com>
> ---
>  hw/kvm/pci-assign.c |   22 ++++++++++++++--------
>  1 files changed, 14 insertions(+), 8 deletions(-)
> 
> diff --git a/hw/kvm/pci-assign.c b/hw/kvm/pci-assign.c
> index 7a0998c..fb58ca9 100644
> --- a/hw/kvm/pci-assign.c
> +++ b/hw/kvm/pci-assign.c
> @@ -46,6 +46,7 @@
>  #define IORESOURCE_IRQ      0x00000400
>  #define IORESOURCE_DMA      0x00000800
>  #define IORESOURCE_PREFETCH 0x00002000  /* No side effects */
> +#define IORESOURCE_MEM_64   0x00100000
>  
>  //#define DEVICE_ASSIGNMENT_DEBUG
>  
> @@ -442,9 +443,13 @@ static int assigned_dev_register_regions(PCIRegion *io_regions,
>  
>          /* handle memory io regions */
>          if (cur_region->type & IORESOURCE_MEM) {
> -            int t = cur_region->type & IORESOURCE_PREFETCH
> -                ? PCI_BASE_ADDRESS_MEM_PREFETCH
> -                : PCI_BASE_ADDRESS_SPACE_MEMORY;
> +            int t = PCI_BASE_ADDRESS_SPACE_MEMORY;
> +            if (cur_region->type & IORESOURCE_PREFETCH) {
> +                t |= PCI_BASE_ADDRESS_MEM_PREFETCH;
> +            }
> +            if (cur_region->type & IORESOURCE_MEM_64) {
> +                t |= PCI_BASE_ADDRESS_MEM_TYPE_64;
> +            }
>  
>              /* map physical memory */
>              pci_dev->v_addrs[i].u.r_virtbase = mmap(NULL, cur_region->size,
> @@ -468,10 +473,10 @@ static int assigned_dev_register_regions(PCIRegion *io_regions,
>                  (cur_region->base_addr & 0xFFF);
>  
>              if (cur_region->size & 0xFFF) {
> -                error_report("PCI region %d at address 0x%" PRIx64 " has "
> -                             "size 0x%" PRIx64 ", which is not a multiple of "
> -                             "4K.  You might experience some performance hit "
> -                             "due to that.",
> +                error_report("PCI region %d at address 0x%016" PRIx64 " has "
> +                             "size 0x%016" PRIx64 ", which is not a multiple "
> +                             "of 4K.  You might experience some performance "
> +                             "hit due to that.",

nit, these changes to %016 don't make sense.  If the size is not a
multiple of 4k, then it's less than 4k, so adding leading zeros is just
a waste.  Also, are BARs that small likely to be 64bit?  Seems like not,
so more unnecessary zeros.  Thanks,

Alex

>                               i, cur_region->base_addr, cur_region->size);
>                  memory_region_init_io(&pci_dev->v_addrs[i].real_iomem,
>                                        &slow_bar_ops, &pci_dev->v_addrs[i],
> @@ -632,7 +637,8 @@ again:
>          rp->valid = 0;
>          rp->resource_fd = -1;
>          size = end - start + 1;
> -        flags &= IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
> +        flags &= IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH
> +                 | IORESOURCE_MEM_64;
>          if (size == 0 || (flags & ~IORESOURCE_PREFETCH) == 0) {
>              continue;
>          }