> On Apr 27, 2016, at 8:10 PM, Ni, Ruiyu <ruiyu...@intel.com> wrote:
>
>>
>> -----Original Message-----
>> From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of Heyi
>> Guo
>> Sent: Saturday, April 23, 2016 4:54 PM
>> To: edk2-devel@lists.01.org
>> Cc: Kinney, Michael D <michael.d.kin...@intel.com>; Heyi Guo
>> <heyi....@linaro.org>; Tian, Feng <feng.t...@intel.com>;
>> Zeng, Star <star.z...@intel.com>
>> Subject: [edk2] [PATCH] MdeModulePkg/TerminalDxe: Set polling rate by serial
>> IO mode
>>
>> Calculate serial input polling rate according to parameters from
>> serial IO mode as below, to fix potential input truncation.
>>
>> Polling interval (100ns) =
>> FifoDepth * (StartBit + DataBits + StopBits + ParityBits) * 10,000,000
>> / BaudRate
>> (StopBits is assumed to be 1 and ParityBits is ignored for simplicity.
>>
>> However, as the event is time sensitive, we need to align the interval
>> to timer interrupt period to make sure the event will be triggered at
>> the expected rate. E.g. if the interval is 2.7ms and timer interrupt
>> period is 1ms, the event will be triggered by time slice sequence as
>> below:
>> 3ms 3ms 2ms 3ms 3ms 2ms...
>>
>> In such case we will adjust the polling interval to be 2ms.
>
> Heyi,
> I remember we had a discussion about the polling interval calculation
> equation a month ago. The equation used in the patch looks good to me.
> Because the timer handler is called sometimes every 3ms but not 2.7ms
> resulting the key loss?
> Just want to confirm with you.
>
Is it safe to make assumptions based on an implementation of an AP? Other
platforms could be using different code?
Thanks,
Andrew Fish
>
> Regards,
> Ray
>
>>
>> Contributed-under: TianoCore Contribution Agreement 1.0
>> Signed-off-by: Heyi Guo <heyi....@linaro.org>
>> Cc: Feng Tian <feng.t...@intel.com>
>> Cc: Star Zeng <star.z...@intel.com>
>> Cc: Michael D Kinney <michael.d.kin...@intel.com>
>> ---
>> .../Universal/Console/TerminalDxe/Terminal.c | 5 +-
>> .../Universal/Console/TerminalDxe/Terminal.h | 28 ++++++-
>> .../Universal/Console/TerminalDxe/TerminalConIn.c | 92
>> ++++++++++++++++++++++
>> .../Universal/Console/TerminalDxe/TerminalDxe.inf | 1 +
>> 4 files changed, 123 insertions(+), 3 deletions(-)
>>
>> diff --git a/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c
>> b/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c
>> index 6fde3b2..2944707 100644
>> --- a/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c
>> +++ b/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c
>> @@ -71,6 +71,7 @@ TERMINAL_DEV mTerminalDevTemplate = {
>> },
>> NULL, // TerminalConsoleModeData
>> 0, // SerialInTimeOut
>> + 0, // KeyboardTimerInterval
>>
>> NULL, // RawFifo
>> NULL, // UnicodeFiFo
>> @@ -984,10 +985,12 @@ TerminalDriverBindingStart (
>> );
>> ASSERT_EFI_ERROR (Status);
>>
>> + TerminalDevice->KeyboardTimerInterval = GetKeyboardTimerInterval (Mode);
>> +
>> Status = gBS->SetTimer (
>> TerminalDevice->TimerEvent,
>> TimerPeriodic,
>> - KEYBOARD_TIMER_INTERVAL
>> + TerminalDevice->KeyboardTimerInterval
>> );
>> ASSERT_EFI_ERROR (Status);
>>
>> diff --git a/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.h
>> b/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.h
>> index 269d2ae..a1ff595 100644
>> --- a/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.h
>> +++ b/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.h
>> @@ -28,6 +28,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER
>> EXPRESS OR IMPLIED.
>> #include <Protocol/DevicePath.h>
>> #include <Protocol/SimpleTextIn.h>
>> #include <Protocol/SimpleTextInEx.h>
>> +#include <Protocol/Timer.h>
>>
>> #include <Library/DebugLib.h>
>> #include <Library/UefiDriverEntryPoint.h>
>> @@ -68,8 +69,6 @@ typedef struct {
>> UINTN Rows;
>> } TERMINAL_CONSOLE_MODE_DATA;
>>
>> -#define KEYBOARD_TIMER_INTERVAL 200000 // 0.02s
>> -
>> #define TERMINAL_DEV_SIGNATURE SIGNATURE_32 ('t', 'm', 'n', 'l')
>>
>> #define TERMINAL_CONSOLE_IN_EX_NOTIFY_SIGNATURE SIGNATURE_32 ('t', 'm', 'e',
>> 'n')
>> @@ -91,6 +90,7 @@ typedef struct {
>> EFI_SIMPLE_TEXT_OUTPUT_MODE SimpleTextOutputMode;
>> TERMINAL_CONSOLE_MODE_DATA *TerminalConsoleModeData;
>> UINTN SerialInTimeOut;
>> + UINT64 KeyboardTimerInterval;
>> RAW_DATA_FIFO *RawFiFo;
>> UNICODE_FIFO *UnicodeFiFo;
>> EFI_KEY_FIFO *EfiKeyFiFo;
>> @@ -1358,4 +1358,28 @@ TerminalConInTimerHandler (
>> IN EFI_EVENT Event,
>> IN VOID *Context
>> );
>> +
>> +/**
>> + Calculate input polling timer interval by serial IO mode.
>> +
>> + @param Mode Pointer to serial IO mode.
>> +
>> + @retval The required polling timer interval in 100ns.
>> +
>> +**/
>> +UINT64
>> +GetKeyboardTimerInterval (
>> + IN EFI_SERIAL_IO_MODE *Mode
>> + );
>> +
>> +/**
>> + Update period of polling timer event.
>> +
>> + @param TerminalDevice The terminal device to update.
>> +**/
>> +VOID
>> +UpdatePollingRate (
>> + IN TERMINAL_DEV *TerminalDevice
>> + );
>> +
>> #endif
>> diff --git a/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
>> b/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
>> index 3be877b..e7788a0 100644
>> --- a/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
>> +++ b/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
>> @@ -15,6 +15,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER
>> EXPRESS OR IMPLIED.
>>
>> #include "Terminal.h"
>>
>> +EFI_TIMER_ARCH_PROTOCOL *gTimer;
>>
>> /**
>> Reads the next keystroke from the input device. The WaitForKey Event can
>> @@ -502,6 +503,94 @@ TerminalConInWaitForKey (
>> }
>>
>> /**
>> + Calculate input polling timer interval by serial IO mode.
>> +
>> + @param Mode Pointer to serial IO mode.
>> +
>> + @retval The required polling timer interval in 100ns.
>> +
>> +**/
>> +UINT64
>> +GetKeyboardTimerInterval (
>> + IN EFI_SERIAL_IO_MODE *Mode
>> + )
>> +{
>> + UINT32 FifoDepth;
>> + UINT64 BaudRate;
>> + UINT64 Interval;
>> + UINT64 TimerPeriod;
>> + EFI_STATUS Status;
>> +
>> + // Make some assumption if the values are not suitable for calculating.
>> + BaudRate = Mode->BaudRate;
>> + if (BaudRate == 0) {
>> + BaudRate = 115200;
>> + }
>> + FifoDepth = Mode->ReceiveFifoDepth;
>> + if (FifoDepth == 0) {
>> + FifoDepth = 1;
>> + }
>> +
>> + // We assume stop bits to be 1 and ignore parity bit to make it simple
>> + // and fast enough to poll.
>> + Interval = DivU64x64Remainder (
>> + FifoDepth * (1 + Mode->DataBits + 1) * 10000000,
>> + Mode->BaudRate,
>> + NULL
>> + );
>> +
>> + // As this is a time sensitive event, we still need to align the
>> + // interval to timer interrupt period.
>> + if (gTimer == NULL) {
>> + Status = gBS->LocateProtocol (
>> + &gEfiTimerArchProtocolGuid,
>> + EFI_NATIVE_INTERFACE,
>> + (VOID **) &gTimer
>> + );
>> + ASSERT_EFI_ERROR (Status);
>> + }
>> +
>> + Status = gTimer->GetTimerPeriod (gTimer, &TimerPeriod);
>> + ASSERT_EFI_ERROR (Status);
>> +
>> + if (Interval <= TimerPeriod) {
>> + return TimerPeriod;
>> + }
>> + return MultU64x64 (DivU64x64Remainder (Interval, TimerPeriod, NULL),
>> TimerPeriod);
>> +}
>> +
>> +
>> +/**
>> + Update period of polling timer event.
>> +
>> + @param TerminalDevice The terminal device to update.
>> +**/
>> +VOID
>> +UpdatePollingRate (
>> + IN TERMINAL_DEV *TerminalDevice
>> + )
>> +{
>> + UINT64 NewInterval;
>> + EFI_STATUS Status;
>> +
>> + NewInterval = GetKeyboardTimerInterval (TerminalDevice->SerialIo->Mode);
>> +
>> + if (TerminalDevice->KeyboardTimerInterval == NewInterval) {
>> + return;
>> + }
>> +
>> + Status = gBS->SetTimer (
>> + TerminalDevice->TimerEvent,
>> + TimerPeriodic,
>> + NewInterval
>> + );
>> + ASSERT_EFI_ERROR (Status);
>> +
>> + TerminalDevice->KeyboardTimerInterval = NewInterval;
>> +}
>> +
>> +
>> +/**
>> Timer handler to poll the key from serial.
>>
>> @param Event Indicates the event that invoke this
>> function.
>> @@ -560,6 +649,9 @@ TerminalConInTimerHandler (
>> TerminalDevice->SerialInTimeOut = SerialInTimeOut;
>> }
>> }
>> +
>> + UpdatePollingRate (TerminalDevice);
>> +
>> //
>> // Check whether serial buffer is empty.
>> // Skip the key transfer loop only if the SerialIo protocol instance
>> diff --git a/MdeModulePkg/Universal/Console/TerminalDxe/TerminalDxe.inf
>> b/MdeModulePkg/Universal/Console/TerminalDxe/TerminalDxe.inf
>> index 0780296..dfd5035 100644
>> --- a/MdeModulePkg/Universal/Console/TerminalDxe/TerminalDxe.inf
>> +++ b/MdeModulePkg/Universal/Console/TerminalDxe/TerminalDxe.inf
>> @@ -84,6 +84,7 @@
>> gEfiSimpleTextInProtocolGuid ## BY_START
>> gEfiSimpleTextInputExProtocolGuid ## BY_START
>> gEfiSimpleTextOutProtocolGuid ## BY_START
>> + gEfiTimerArchProtocolGuid ## CONSUMES
>>
>> [Pcd]
>> gEfiMdePkgTokenSpaceGuid.PcdDefaultTerminalType ##
>> SOMETIMES_CONSUMES
>> --
>> 2.7.0
>>
>> _______________________________________________
>> edk2-devel mailing list
>> edk2-devel@lists.01.org
>> https://lists.01.org/mailman/listinfo/edk2-devel
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