Re: [PATCH 3/5] OvmfPkg/IndustryStandard: add QemuFwCfgDma.h

[Jordan Justen <jordan.l.justen@intel.com>]

On 2016-12-01 09:56:31, Laszlo Ersek wrote:
> Add the type and macro definitions related to QEMU's DMA-like fw_cfg
> access method in a dedicated header file.
> 
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Laszlo Ersek <lersek@redhat.com>
> ---
>  OvmfPkg/Include/IndustryStandard/QemuFwCfgDma.h | 50 ++++++++++++++++++++

What do you think about just
OvmfPkg/Include/IndustryStandard/QemuFwCfg.h?

Arguably, the FIRMWARE_CONFIG_ITEM enums could be moved there as
well...

Then again, I think we could also just put this content into
OvmfPkg/Include/Library/QemuFwCfgLib.h.

-Jordan

>  1 file changed, 50 insertions(+)
> 
> diff --git a/OvmfPkg/Include/IndustryStandard/QemuFwCfgDma.h b/OvmfPkg/Include/IndustryStandard/QemuFwCfgDma.h
> new file mode 100644
> index 000000000000..37a5804adb05
> --- /dev/null
> +++ b/OvmfPkg/Include/IndustryStandard/QemuFwCfgDma.h
> @@ -0,0 +1,50 @@
> +/** @file
> +  Macro and type definitions related to QEMU's DMA-like fw_cfg access method,
> +  based on "docs/specs/fw_cfg.txt" in the QEMU tree.
> +
> +  Copyright (C) 2016, Red Hat, Inc.
> +
> +  This program and the accompanying materials are licensed and made available
> +  under the terms and conditions of the BSD License which accompanies this
> +  distribution.  The full text of the license may be found at
> +  http://opensource.org/licenses/bsd-license.php
> +
> +  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
> +  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +**/
> +
> +
> +#ifndef __FW_CFG_DMA__
> +#define __FW_CFG_DMA__
> +
> +#include <Base.h>
> +
> +//
> +// If the following bit is set in the UINT32 fw_cfg revision / feature bitmap
> +// -- read from key 0x0001 with the basic IO Port or MMIO method --, then the
> +// DMA interface is available.
> +//
> +#define FW_CFG_F_DMA BIT1
> +
> +//
> +// Communication structure for the DMA access method. All fields are encoded in
> +// big endian.
> +//
> +#pragma pack (1)
> +typedef struct {
> +  UINT32 Control;
> +  UINT32 Length;
> +  UINT64 Address;
> +} FW_CFG_DMA_ACCESS;
> +#pragma pack ()
> +
> +//
> +// Macros for the FW_CFG_DMA_ACCESS.Control bitmap (in native encoding).
> +//
> +#define FW_CFG_DMA_CTL_ERROR  BIT0
> +#define FW_CFG_DMA_CTL_READ   BIT1
> +#define FW_CFG_DMA_CTL_SKIP   BIT2
> +#define FW_CFG_DMA_CTL_SELECT BIT3
> +#define FW_CFG_DMA_CTL_WRITE  BIT4
> +
> +#endif
> -- 
> 2.9.2
> 
>