[U-Boot] [PATCH] PCI: add 64-bit prefetchable memory support

[Bin Meng]

Hi David,

On Mon, Feb 2, 2015 at 11:30 AM,  <fenghua at phytium.com.cn> wrote:
> From: David Feng <fenghua at phytium.com.cn>
>
> PCI specification allow prefetchable memory to be 32-bit or 64-bit.
> PCI express specification states that all memmory bars for prefetchable
> memory must be implemented as 64-bit. They all require that 64 bit
> prefetchble memory are suported especially when u-boot is ported to
> more and more 64bit processors.
>
> Signed-off-by: David Feng <fenghua at phytium.com.cn>
> ---

This patch looks good to me, except a minor issue below.

>  drivers/pci/pci_auto.c |   36 +++++++++++++++++++++++++++++++++++-
>  1 file changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/pci_auto.c b/drivers/pci/pci_auto.c
> index ed92857..5ddb0b8 100644
> --- a/drivers/pci/pci_auto.c
> +++ b/drivers/pci/pci_auto.c
> @@ -223,9 +223,12 @@ void pciauto_prescan_setup_bridge(struct pci_controller *hose,
>         struct pci_region *pci_mem = hose->pci_mem;
>         struct pci_region *pci_prefetch = hose->pci_prefetch;
>         struct pci_region *pci_io = hose->pci_io;
> -       u16 cmdstat;
> +       u16 cmdstat, prefechable_64;
>
>         pci_hose_read_config_word(hose, dev, PCI_COMMAND, &cmdstat);
> +       pci_hose_read_config_word(hose, dev, PCI_PREF_MEMORY_BASE,
> +                               &prefechable_64);
> +       prefechable_64 &= 0x1;

Please use PCI_PREF_RANGE_TYPE_64.

>
>         /* Configure bus number registers */
>         pci_hose_write_config_byte(hose, dev, PCI_PRIMARY_BUS,
> @@ -252,12 +255,26 @@ void pciauto_prescan_setup_bridge(struct pci_controller *hose,
>                 /* Set up memory and I/O filter limits, assume 32-bit I/O space */
>                 pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE,
>                                         (pci_prefetch->bus_lower & 0xfff00000) >> 16);
> +               if (prefechable_64)
> +#ifdef CONFIG_SYS_PCI_64BIT
> +                       pci_hose_write_config_dword(hose, dev,
> +                                       PCI_PREF_BASE_UPPER32,
> +                                       pci_prefetch->bus_lower >> 32);
> +#else
> +                       pci_hose_write_config_dword(hose, dev,
> +                                       PCI_PREF_BASE_UPPER32,
> +                                       0x0);
> +#endif
>
>                 cmdstat |= PCI_COMMAND_MEMORY;
>         } else {
>                 /* We don't support prefetchable memory for now, so disable */
>                 pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE, 0x1000);
>                 pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT, 0x0);
> +               if (prefechable_64) {
> +                       pci_hose_write_config_word(hose, dev, PCI_PREF_BASE_UPPER32, 0x0);
> +                       pci_hose_write_config_word(hose, dev, PCI_PREF_LIMIT_UPPER32, 0x0);
> +               }
>         }
>
>         if (pci_io) {
> @@ -297,11 +314,28 @@ void pciauto_postscan_setup_bridge(struct pci_controller *hose,
>         }
>
>         if (pci_prefetch) {
> +               u16 prefechable_64;
> +
> +               pci_hose_read_config_word(hose, dev,
> +                                       PCI_PREF_MEMORY_LIMIT,
> +                                       &prefechable_64);
>
> +               prefechable_64 &= 0x1;

Ditto.

>                 /* Round memory allocator to 1MB boundary */
>                 pciauto_region_align(pci_prefetch, 0x100000);
>
>                 pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT,
>                                 (pci_prefetch->bus_lower - 1) >> 16);
> +               if (prefechable_64)
> +#ifdef CONFIG_SYS_PCI_64BIT
> +                       pci_hose_write_config_dword(hose, dev,
> +                                       PCI_PREF_LIMIT_UPPER32,
> +                                       (pci_prefetch->bus_lower - 1) >> 32);
> +#else
> +                       pci_hose_write_config_dword(hose, dev,
> +                                       PCI_PREF_LIMIT_UPPER32,
> +                                       0x0);
> +#endif
>         }
>
>         if (pci_io) {
> --

Regards,
Bin