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

[Laszlo Ersek <lersek@redhat.com>]

On 12/01/16 20:34, Jordan Justen wrote:
> 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.

Adding this stuff to "OvmfPkg/Include/Library/QemuFwCfgLib.h" sounds
good to me; I'll do that in v2.

Thanks!
Laszlo

> -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
>>
>>