[SeaBIOS] [PATCH 10/12] Calculate pci region stats on demand

[Alexey Korolev]

A flowed text. Please apply another [10/12] in this series.


On Tue, 2012-04-24 at 18:23 +1200, Alexey Korolev wrote:
> Do not store pci region stats - instead calulate the
> sum and alignment on demand.
> 
> Signed-off-by: Alexey Korolev <alexey.korolev at endace.com>
> ---
>  src/pciinit.c |   57
> +++++++++++++++++++++++++++++++++++----------------------
>  1 files changed, 35 insertions(+), 22 deletions(-)
> 
> diff --git a/src/pciinit.c b/src/pciinit.c
> index 0d66dbe..a6cf98b 100644
> --- a/src/pciinit.c
> +++ b/src/pciinit.c
> @@ -40,8 +40,6 @@ struct pci_region_entry {
>  };
>  
>  struct pci_region {
> -    /* pci region stats */
> -    u64 sum, align;
>      /* pci region assignments */
>      u64 base;
>      struct pci_region_entry *list;
> @@ -369,6 +367,25 @@ static int pci_bios_bridge_region_is64(struct
> pci_region *r,
>      return 1;
>  }
>  
> +static u64 pci_region_align(struct pci_region *r)
> +{
> +    if (!r->list)
> +        return 1;
> +    // The first entry in the sorted list has the largest alignment
> +    return r->list->align;
> +}
> +
> +static u64 pci_region_sum(struct pci_region *r)
> +{
> +    struct pci_region_entry *entry = r->list;
> +    u64 sum = 0;
> +    while (entry) {
> +        sum += entry->size;
> +        entry = entry->next;
> +   }
> +   return sum;
> +}
> +
>  static struct pci_region_entry *
>  pci_region_create_entry(struct pci_bus *bus, struct pci_device *dev,
>                          int bar, u64 size, u64 align, int type, int
> is64)
> @@ -394,10 +411,6 @@ pci_region_create_entry(struct pci_bus *bus, struct
> pci_device *dev,
>      }
>      entry->next = *pprev;
>      *pprev = entry;
> -
> -    bus->r[type].sum += size;
> -    if (bus->r[type].align < align)
> -        bus->r[type].align = align;
>      return entry;
>  }
>  
> @@ -446,9 +459,9 @@ static int pci_bios_check_devices(struct pci_bus
> *busses)
>          for (type = 0; type < PCI_REGION_TYPE_COUNT; type++) {
>              u64 align = (type == PCI_REGION_TYPE_IO) ?
>                  PCI_BRIDGE_IO_MIN : PCI_BRIDGE_MEM_MIN;
> -            if (s->r[type].align > align)
> -                align = s->r[type].align;
> -            u64 size = ALIGN(s->r[type].sum, align);
> +            if (pci_region_align(&s->r[type]) > align)
> +                 align = pci_region_align(&s->r[type]);
> +            u64 size = ALIGN(pci_region_sum(&s->r[type]), align);
>              int is64 = pci_bios_bridge_region_is64(&s->r[type],
>                                              s->bus_dev, type);
>              // entry->bar is -1 if the entry represents a bridge region
> @@ -464,26 +477,26 @@ static int pci_bios_check_devices(struct pci_bus
> *busses)
>      return 0;
>  }
>  
> -#define ROOT_BASE(top, sum, align) ALIGN_DOWN((top)-(sum),(align) ?: 1)
> -
>  // Setup region bases (given the regions' size and alignment)
>  static void pci_bios_init_root_regions(struct pci_bus *bus)
>  {
> -    u64 start = BUILD_PCIMEM_START;
> -    u64 end   = BUILD_PCIMEM_END;
> -
>      bus->r[PCI_REGION_TYPE_IO].base = 0xc000;
>  
> -    int reg1 = PCI_REGION_TYPE_PREFMEM, reg2 = PCI_REGION_TYPE_MEM;
> -    if (bus->r[reg1].align < bus->r[reg2].align) {
> +    struct pci_region *r_end = &bus->r[PCI_REGION_TYPE_PREFMEM];
> +    struct pci_region *r_start = &bus->r[PCI_REGION_TYPE_MEM];
> +
> +    if (pci_region_align(r_start) < pci_region_align(r_end)) {
>          // Swap regions to improve alignment.
> -        reg1 = PCI_REGION_TYPE_MEM;
> -        reg2 = PCI_REGION_TYPE_PREFMEM;
> +        r_end = r_start;
> +        r_start = &bus->r[PCI_REGION_TYPE_PREFMEM];
>      }
> -    bus->r[reg2].base = ROOT_BASE(end, bus->r[reg2].sum,
> bus->r[reg2].align);
> -    bus->r[reg1].base = ROOT_BASE(bus->r[reg2].base, bus->r[reg1].sum
> -                                  , bus->r[reg1].align);
> -    if (bus->r[reg1].base < start)
> +    r_end->base = ALIGN_DOWN((BUILD_PCIMEM_END -
> pci_region_sum(r_end)),
> +                                pci_region_align(r_end));
> +    r_start->base = ALIGN_DOWN((r_end->base - pci_region_sum(r_start)),
> +                                pci_region_align(r_start));
> +
> +    if ((r_start->base < BUILD_PCIMEM_START) ||
> +         (r_start->base > BUILD_PCIMEM_END))
>          // Memory range requested is larger than available.
>          panic("PCI: out of address space\n");
>  }