[U-Boot] [PATCH 3/3] drivers: pci: pci-uclass: Get PCI dma regions support

[Bin Meng]

Hi Vladimir,

On Sat, Nov 23, 2019 at 6:23 AM Vladimir Olovyannikov
<vladimir.olovyannikov at broadcom.com> wrote:
>
> From: Srinath Mannam <srinath.mannam at broadcom.com>
>
> Add API to parse dma-regions given in PCIe host controller
> DT node.
>
> Signed-off-by: Srinath Mannam <srinath.mannam at broadcom.com>
> Signed-off-by: Vladimir Olovyannikov <vladimir.olovyannikov at broadcom.com>
> ---
>  drivers/pci/pci-uclass.c | 41 ++++++++++++++++++++++++++++++++++++++++
>  include/pci.h            |  2 ++
>  2 files changed, 43 insertions(+)
>
> diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
> index eb7a01fd55..ddc2d5cf2c 100644
> --- a/drivers/pci/pci-uclass.c
> +++ b/drivers/pci/pci-uclass.c
> @@ -1166,6 +1166,47 @@ ulong pci_conv_size_to_32(ulong old, ulong value, uint offset,
>         return value;
>  }
>
> +int pci_get_dma_regions(struct udevice *dev, struct pci_region *memp, int index)
> +{
> +       int pci_addr_cells, addr_cells, size_cells;
> +       int cells_per_record;
> +       const u32 *prop;
> +       int len;
> +       int i = 0;
> +
> +       prop = ofnode_get_property(dev_ofnode(dev), "dma-ranges", &len);
> +       if (!prop) {
> +               dev_err(dev, "%s: Cannot decode dma-ranges\n", __func__);
> +               return -EINVAL;
> +       }
> +
> +       pci_addr_cells = ofnode_read_simple_addr_cells(dev_ofnode(dev));
> +       addr_cells = ofnode_read_simple_addr_cells(dev_ofnode(dev->parent));
> +       size_cells = ofnode_read_simple_size_cells(dev_ofnode(dev));
> +
> +       /* PCI addresses are always 3-cells */
> +       len /= sizeof(u32);
> +       cells_per_record = pci_addr_cells + addr_cells + size_cells;
> +       debug("%s: len=%d, cells_per_record=%d\n", __func__, len,
> +             cells_per_record);
> +
> +       while (len) {
> +               memp->bus_start = fdtdec_get_number(prop + 1, 2);
> +               prop += pci_addr_cells;
> +               memp->phys_start = fdtdec_get_number(prop, addr_cells);
> +               prop += addr_cells;
> +               memp->size = fdtdec_get_number(prop, size_cells);
> +               prop += size_cells;
> +
> +               if (i == index)
> +                       return 0;
> +               i++;
> +               len -= cells_per_record;
> +       }
> +
> +       return -EINVAL;
> +}
> +
>  int pci_get_regions(struct udevice *dev, struct pci_region **iop,
>                     struct pci_region **memp, struct pci_region **prefp)
>  {
> diff --git a/include/pci.h b/include/pci.h
> index ff59ac0e69..ef55f54ea5 100644
> --- a/include/pci.h
> +++ b/include/pci.h
> @@ -1284,6 +1284,8 @@ struct udevice *pci_get_controller(struct udevice *dev);
>  int pci_get_regions(struct udevice *dev, struct pci_region **iop,
>                     struct pci_region **memp, struct pci_region **prefp);
>
> +int

nits: this should be put on the same line of the function name.
Besides, would you please add the function descriptions with
parameters and return value?

> +pci_get_dma_regions(struct udevice *dev, struct pci_region *memp, int index);

Should have one blank line

>  /**
>   * dm_pci_write_bar32() - Write the address of a BAR
>   *
> --

Regards,
Bin