Re: [Qemu-devel] [PATCH v6 2/3] pci: add QEMU-specific PCI capability structure

[Marcel Apfelbaum]

On 13/08/2017 19:03, Aleksandr Bezzubikov wrote:
> On PCI init PCI bridge devices may need some
> extra info about bus number to reserve, IO, memory and
> prefetchable memory limits. QEMU can provide this
> with special vendor-specific PCI capability.
>
> This capability is intended to be used only
> for Red Hat PCI bridges, i.e. QEMU cooperation.


Reviewed-by: Marcel Apfelbaum <address@hidden>

Thanks,
Marcel

> Signed-off-by: Aleksandr Bezzubikov <address@hidden>
> ---
>   src/fw/dev-pci.h | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 53 insertions(+)
>   create mode 100644 src/fw/dev-pci.h
>
> diff --git a/src/fw/dev-pci.h b/src/fw/dev-pci.h
> new file mode 100644
> index 0000000..0dc5556
> --- /dev/null
> +++ b/src/fw/dev-pci.h
> @@ -0,0 +1,53 @@
> +#ifndef _PCI_CAP_H
> +#define _PCI_CAP_H
> +
> +#include "types.h"
> +
> +/*
> + *
> + * QEMU-specific vendor(Red Hat)-specific capability.
> + * It's intended to provide some hints for firmware to init PCI devices.
> + *
> + * Its structure is shown below:
> + *
> + * Header:
> + *
> + * u8 id;       Standard PCI Capability Header field
> + * u8 next;     Standard PCI Capability Header field
> + * u8 len;      Standard PCI Capability Header field
> + * u8 type;     Red Hat vendor-specific capability type
> + * Data:
> + *
> + * u32 bus_res;     minimum bus number to reserve;
> + *                  this is necessary for PCI Express Root Ports
> + *                  to support PCI bridges hotplug
> + * u64 io;          IO space to reserve
> + * u32 mem;         non-prefetchable memory to reserve
> + *
> + * At most of the following two fields may be set to a value
> + * different from 0xFF...F:
> + * u32 prefetchable_mem_32;     prefetchable memory to reserve (32-bit MMIO)
> + * u64 prefetchable_mem_64;     prefetchable memory to reserve (64-bit MMIO)
> + *
> + * If any field value in Data section is 0xFF...F,
> + * it means that such kind of reservation is not needed and must be ignored.
> + *
> +*/
> +
> +/* Offset of vendor-specific capability type field */
> +#define PCI_CAP_REDHAT_TYPE_OFFSET  3
> +
> +/* List of valid Red Hat vendor-specific capability types */
> +#define REDHAT_CAP_RESOURCE_RESERVE 1
> +
> +
> +/* Offsets of RESOURCE_RESERVE capability fields */
> +#define RES_RESERVE_BUS_RES        4
> +#define RES_RESERVE_IO             8
> +#define RES_RESERVE_MEM            16
> +#define RES_RESERVE_PREF_MEM_32    20
> +#define RES_RESERVE_PREF_MEM_64    24
> +#define RES_RESERVE_CAP_SIZE       32
> +
> +#endif /* _PCI_CAP_H */
> +