> -----Original Message-----
> From: Loh, Tien Hock
> Sent: Thursday, April 25, 2019 2:13 PM
> To: thlo...@gmail.com devel@edk2.groups.io; Kinney, Michael D
> Cc: Loh, Tien Hock; Wang, Jian J; Wu, Hao A
> Subject: [PATCH 1/1] MdeModulePkg: BaseSerialPortLib16550: Add Mmio32
> support
>
> From: "Tien Hock, Loh" <tien.hock....@intel.com>
>
> Some busses doesn't allow 8 bit MMIO read/write, this adds support for
> 32 bits read/write
>
> Signed-off-by: "Tien Hock, Loh" <tien.hock....@intel.com>
> Cc: Jian J Wang <jian.j.w...@intel.com>
> Cc: Hao Wu <hao.a...@intel.com>
>
> ---
> v4
> - Updates Pcd name to a better name: PcdSerialRegisterAccessWidth
> v3
> - Updates the Pcd to be UINT8 to allow more options such as 16 bits access
> in the future
> - Updated copyright date
> v2
> - Updates the Pcd name to PcdSerialMmio32BitAccess and access 32 bits
> register if PcdSerialUseMmio and PcdSerialMmio32BitAccess is set
> ---
> .../Library/BaseSerialPortLib16550/BaseSerialPortLib16550.c | 12
> +++++++++++-
> .../BaseSerialPortLib16550/BaseSerialPortLib16550.inf | 3 ++-
> MdeModulePkg/MdeModulePkg.dec | 7 +++++++
> 3 files changed, 20 insertions(+), 2 deletions(-)
>
> diff --git
> a/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.c
> b/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.c
> index 34df34d..5910606 100644
> --- a/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.c
> +++
> b/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.c
> @@ -2,7 +2,7 @@
> 16550 UART Serial Port library functions
>
> (C) Copyright 2014 Hewlett-Packard Development Company, L.P.<BR>
> - Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
> + Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> Copyright (c) 2018, AMD Incorporated. All rights reserved.<BR>
>
> SPDX-License-Identifier: BSD-2-Clause-Patent
> @@ -77,6 +77,11 @@ SerialPortReadRegister (
> )
> {
> if (PcdGetBool (PcdSerialUseMmio)) {
> + if (PcdGet8 (PcdSerialRegisterAccessWidth) == 8) {
> + return MmioRead8 (Base + Offset * PcdGet32 (PcdSerialRegisterStride));
> + } else if (PcdGet8 (PcdSerialRegisterAccessWidth) == 32) {
> + return (UINT8) MmioRead32 (Base + Offset * PcdGet32
> (PcdSerialRegisterStride));
> + }
> return MmioRead8 (Base + Offset * PcdGet32 (PcdSerialRegisterStride));
Hello Tien Hock,
Sorry for the delayed response.
The above codes deal with 3 cases (also true for SerialPortWriteRegister):
1. PcdSerialRegisterAccessWidth is set to 8
2. PcdSerialRegisterAccessWidth is set to 32
3. PcdSerialRegisterAccessWidth is set to values other than 8 or 32
(For 3, the behavior falls back to default, which is okay to me)
For case 1 and 3, they end up calling MmioRead8(). So IMO, maybe we can
simplifies the logic to:
if (PcdGet8 (PcdSerialRegisterAccessWidth) == 32) {
MmioRead32 (...);
} else {
MmioRead8 (...);
}
What do you think?
Also, could you help to update the function description comments for
* SerialPortReadRegister()
* SerialPortWriteRegister()
to reflect their behavior with regard to the new PCD?
Lastly, when sending a new version of the patch, could you help to append
option '--subject-prefix="PATCH vN"' to the 'git-format-patch' command. So
for this v4 patch, it will be '--subject-prefix="PATCH v4"'.
Best Regards,
Hao Wu
> } else {
> return IoRead8 (Base + Offset * PcdGet32 (PcdSerialRegisterStride));
> @@ -104,6 +109,11 @@ SerialPortWriteRegister (
> )
> {
> if (PcdGetBool (PcdSerialUseMmio)) {
> + if (PcdGet8 (PcdSerialRegisterAccessWidth) == 8) {
> + return MmioWrite8 (Base + Offset * PcdGet32 (PcdSerialRegisterStride),
> Value);
> + } else if (PcdGet8 (PcdSerialRegisterAccessWidth) == 32) {
> + return (UINT8) MmioWrite32 (Base + Offset * PcdGet32
> (PcdSerialRegisterStride), (UINT8)Value);
> + }
> return MmioWrite8 (Base + Offset * PcdGet32 (PcdSerialRegisterStride),
> Value);
> } else {
> return IoWrite8 (Base + Offset * PcdGet32 (PcdSerialRegisterStride),
> Value);
> diff --git
> a/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
> b/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
> index b60779c..8b4ae3f 100644
> ---
> a/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
> +++
> b/MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
> @@ -1,7 +1,7 @@
> ## @file
> # SerialPortLib instance for 16550 UART.
> #
> -# Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> # SPDX-License-Identifier: BSD-2-Clause-Patent
> #
> ##
> @@ -29,6 +29,7 @@
> BaseSerialPortLib16550.c
>
> [Pcd]
> + gEfiMdeModulePkgTokenSpaceGuid.PcdSerialRegisterAccessWidth ##
> SOMETIMES_CONSUMES
> gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseMmio ##
> CONSUMES
> gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseHardwareFlowControl ##
> CONSUMES
> gEfiMdeModulePkgTokenSpaceGuid.PcdSerialDetectCable ##
> SOMETIMES_CONSUMES
> diff --git a/MdeModulePkg/MdeModulePkg.dec
> b/MdeModulePkg/MdeModulePkg.dec
> index be84916..2ef48f2 100644
> --- a/MdeModulePkg/MdeModulePkg.dec
> +++ b/MdeModulePkg/MdeModulePkg.dec
> @@ -1170,6 +1170,13 @@
> # @Prompt Serial port registers use MMIO.
>
> gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseMmio|FALSE|BOOLEAN|0x00
> 020000
>
> + ## Indicates the access width for 16550 serial port registers.
> + # Default is 8-bit access mode.<BR><BR>
> + # 8 - 16550 serial port registers are accessed in 8-bit width.<BR>
> + # 32 - 16550 serial port registers are accessed in 32-bit width.<BR>
> + # @Prompt Serial port register access width.
> +
> gEfiMdeModulePkgTokenSpaceGuid.PcdSerialRegisterAccessWidth|8|UINT8|0x
> 00020007
> +
> ## Indicates if the 16550 serial port hardware flow control will be
> enabled.
> Default is FALSE.<BR><BR>
> # TRUE - 16550 serial port hardware flow control will be enabled.<BR>
> # FALSE - 16550 serial port hardware flow control will be disabled.<BR>
> --
> 2.2.2
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#39622): https://edk2.groups.io/g/devel/message/39622
Mute This Topic: https://groups.io/mt/31318235/21656
Group Owner: devel+ow...@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com]
-=-=-=-=-=-=-=-=-=-=-=-
