Sami, The BaseSerialPortLib16550 supports I/O port, MMIO, and PCI based UARTs.
PCDs are used to select the modes. I would like to see the BaseSerialPortLib16550 used instead of the serial port lib in PcAtChipsetPkg. Mike > -----Original Message----- > From: edk2-devel [mailto:[email protected]] > On Behalf Of Sami Mujawar > Sent: Friday, October 12, 2018 8:06 AM > To: Ard Biesheuvel <[email protected]> > Cc: Ni, Ruiyu <[email protected]>; nd <[email protected]>; > Stephanie Hughes-Fitt <[email protected]>; > [email protected] > Subject: Re: [edk2] [PATCH v1 1/6] PcAtChipsetPkg: Add > MMIO Support to SerialIo Lib > > Hi Ard, > > I believe you are referring to > MdeModulePkg\Library\BaseSerialPortLib16550\BaseSerialPor > tLib16550.inf > I have tried using this Serial Port Library. However, > this has a dependency on PciLib which is difficult to > resolve as we use the Serial port early in the boot. > Please do let me know if you know a workaround to solve > this issue. > > Regards, > > Sami Mujawar > > -----Original Message----- > From: Ard Biesheuvel <[email protected]> > Sent: 12 October 2018 03:50 PM > To: Sami Mujawar <[email protected]> > Cc: [email protected]; Leif Lindholm > <[email protected]>; Ruiyu Ni > <[email protected]>; Evan Lloyd <[email protected]>; > Matteo Carlini <[email protected]>; Stephanie > Hughes-Fitt <[email protected]>; nd > <[email protected]> > Subject: Re: [PATCH v1 1/6] PcAtChipsetPkg: Add MMIO > Support to SerialIo Lib > > On 12 October 2018 at 16:40, Sami Mujawar > <[email protected]> wrote: > > Some virtual machine managers like kvmtool emulate the > PC AT Serial > > Port UART in the MMIO space so that architectures that > do not support > > I/O Mapped I/O can use the UART. > > > > This patch adds MMIO support to the PC AT > SerialPortLib. > > > > PcdSerialUseMmio is used to select I/O or MMIO support. > > If PcdSerialUseMmio is > > TRUE - The value is read/written from MMIO space. > > FALSE - The value is read/written from I/O space. > > The Default is I/O space. > > > > IIUC kvmtool exposes a 8250, and our 8250 driver already > implements support for MMIO mapped registers. Can't you > use that instead? > > > Contributed-under: TianoCore Contribution Agreement 1.1 > > Signed-off-by: Sami Mujawar <[email protected]> > > --- > > The changes can be seen at > > > https://github.com/samimujawar/edk2/commit/84f908387d2031 > def5d374759e7 > > ad4cf90786c91 > > > > Notes: > > v1: > > - Add support to read/write from UART registers > using MMIO access > > [SAMI] > > > > PcAtChipsetPkg/Library/SerialIoLib/SerialIoLib.inf | > 4 + > > PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c | 98 > > ++++++++++++++++---- > > 2 files changed, 84 insertions(+), 18 deletions(-) > > > > diff --git > a/PcAtChipsetPkg/Library/SerialIoLib/SerialIoLib.inf > > b/PcAtChipsetPkg/Library/SerialIoLib/SerialIoLib.inf > > index > > > 959d6e27c9812d201d44d9249070ab7758cbfe00..d0689793040fd93 > 0701b02dae51f > > f59ea16a10c4 100644 > > --- > a/PcAtChipsetPkg/Library/SerialIoLib/SerialIoLib.inf > > +++ > b/PcAtChipsetPkg/Library/SerialIoLib/SerialIoLib.inf > > @@ -2,6 +2,7 @@ > > # Library instance for SerialIo library class > > # > > # Copyright (c) 2006 - 2014, Intel Corporation. All > rights > > reserved.<BR> > > +# Copyright (c) 2018, ARM Limited. All rights > reserved.<BR> > > # 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 @@ -23,6 +24,7 @@ [Defines] > > > > [Packages] > > MdePkg/MdePkg.dec > > + MdeModulePkg/MdeModulePkg.dec > > > > [LibraryClasses] > > BaseLib > > @@ -31,3 +33,5 @@ [LibraryClasses] > > [Sources] > > SerialPortLib.c > > > > +[FixedPcd] > > + gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseMmio > ## CONSUMES > > diff --git > a/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c > > b/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c > > index > > > d1a1c6a03facad09e781b5605e22a24e5f51c618..898e5f957aae998 > 624189c6b5389 > > 12da0439dfe8 100644 > > --- > a/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c > > +++ > b/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c > > @@ -2,6 +2,8 @@ > > UART Serial Port library functions > > > > Copyright (c) 2006 - 2018, Intel Corporation. All > rights > > reserved.<BR> > > + Copyright (c) 2018, ARM Limited. All rights > reserved.<BR> > > + > > 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 > > @@ -57,6 +59,66 @@ UINT8 gParity = 0; > > UINT8 gBreakSet = 0; > > > > /** > > + Reads an 8-bit value from the serial port. > > + > > + This function checks PcdSerialUseMmio to determine > if I/O mapped > > + IO or Memory Mapped IO operations must be performed > on the serial > > + port. It then uses the appropriate interface to read > the Value from > > + the serial port. > > + > > + If PcdSerialUseMmio is TRUE, then the value is read > from MMIO space. > > + If PcdSerialUseMmio is FALSE, then the value is read > from I/O space. > > + > > + @param Address The UART register to read from. > > + > > + @return The value read from the serial port. > > + > > +**/ > > +STATIC > > +UINT8 > > +SerialPortRead8 ( > > + IN UINTN Address > > +) > > +{ > > + if (FixedPcdGetBool (PcdSerialUseMmio)) { > > + return MmioRead8 (Address); > > + } > > + > > + return IoRead8 (Address); > > +} > > + > > +/** > > + Writes an 8-bit value to the serial port. > > + > > + This function checks PcdSerialUseMmio to determine > if I/O mapped > > + IO or Memory Mapped IO operations must be performed > on the serial > > + port. It then uses the appropriate interface to > write the Value to > > + the serial port. > > + > > + If PcdSerialUseMmio is TRUE, then the value is > written to MMIO space. > > + If PcdSerialUseMmio is FALSE, then the value is > written to I/O space. > > + > > + @param Address The UART register to write. > > + @param Value The value to write to the I/O > port. > > + > > + @return The value written to the serial port. > > + > > +**/ > > +STATIC > > +UINT8 > > +SerialPortWrite8 ( > > + IN UINTN Address, > > + IN UINT8 Value > > +) > > +{ > > + if (FixedPcdGetBool (PcdSerialUseMmio)) { > > + return MmioWrite8 (Address, Value); > > + } > > + > > + return IoWrite8 (Address, Value); > > +} > > + > > +/** > > Initialize the serial device hardware. > > > > If no initialization is required, then return > RETURN_SUCCESS. > > @@ -91,19 +153,19 @@ SerialPortInitialize ( > > // Set communications format > > // > > OutputData = (UINT8) ((DLAB << 7) | (gBreakSet << 6) > | (gParity << > > 3) | (gStop << 2) | Data); > > - IoWrite8 (gUartBase + LCR_OFFSET, OutputData); > > + SerialPortWrite8 (gUartBase + LCR_OFFSET, > OutputData); > > > > // > > // Configure baud rate > > // > > - IoWrite8 (gUartBase + BAUD_HIGH_OFFSET, (UINT8) > (Divisor >> 8)); > > - IoWrite8 (gUartBase + BAUD_LOW_OFFSET, (UINT8) > (Divisor & 0xff)); > > + SerialPortWrite8 (gUartBase + BAUD_HIGH_OFFSET, > (UINT8) (Divisor >> > > + 8)); > > + SerialPortWrite8 (gUartBase + BAUD_LOW_OFFSET, > (UINT8) (Divisor & > > + 0xff)); > > > > // > > // Switch back to bank 0 > > // > > OutputData = (UINT8) ( (gBreakSet << 6) | (gParity > << 3) | (gStop > > << 2) | Data); > > - IoWrite8 (gUartBase + LCR_OFFSET, OutputData); > > + SerialPortWrite8 (gUartBase + LCR_OFFSET, > OutputData); > > > > return RETURN_SUCCESS; > > } > > @@ -148,9 +210,9 @@ SerialPortWrite ( > > // Wait for the serail port to be ready. > > // > > do { > > - Data = IoRead8 ((UINT16) gUartBase + > LSR_OFFSET); > > + Data = SerialPortRead8 ((UINT16) gUartBase + > LSR_OFFSET); > > } while ((Data & LSR_TXRDY) == 0); > > - IoWrite8 ((UINT16) gUartBase, *Buffer++); > > + SerialPortWrite8 ((UINT16) gUartBase, *Buffer++); > > } > > > > return Result; > > @@ -189,10 +251,10 @@ SerialPortRead ( > > // Wait for the serail port to be ready. > > // > > do { > > - Data = IoRead8 ((UINT16) gUartBase + > LSR_OFFSET); > > + Data = SerialPortRead8 ((UINT16) gUartBase + > LSR_OFFSET); > > } while ((Data & LSR_RXDA) == 0); > > > > - *Buffer++ = IoRead8 ((UINT16) gUartBase); > > + *Buffer++ = SerialPortRead8 ((UINT16) gUartBase); > > } > > > > return Result; > > @@ -220,7 +282,7 @@ SerialPortPoll ( > > // > > // Read the serial port status. > > // > > - Data = IoRead8 ((UINT16) gUartBase + LSR_OFFSET); > > + Data = SerialPortRead8 ((UINT16) gUartBase + > LSR_OFFSET); > > > > return (BOOLEAN) ((Data & LSR_RXDA) != 0); } @@ - > 253,7 +315,7 @@ > > SerialPortSetControl ( > > // > > // Read the Modem Control Register. > > // > > - Mcr = IoRead8 ((UINT16) gUartBase + MCR_OFFSET); > > + Mcr = SerialPortRead8 ((UINT16) gUartBase + > MCR_OFFSET); > > Mcr &= (~(MCR_DTRC | MCR_RTS)); > > > > if ((Control & EFI_SERIAL_DATA_TERMINAL_READY) == > > EFI_SERIAL_DATA_TERMINAL_READY) { @@ -267,7 +329,7 @@ > SerialPortSetControl ( > > // > > // Write the Modem Control Register. > > // > > - IoWrite8 ((UINT16) gUartBase + MCR_OFFSET, Mcr); > > + SerialPortWrite8 ((UINT16) gUartBase + MCR_OFFSET, > Mcr); > > > > return RETURN_SUCCESS; > > } > > @@ -297,7 +359,7 @@ SerialPortGetControl ( > > // > > // Read the Modem Status Register. > > // > > - Msr = IoRead8 ((UINT16) gUartBase + MSR_OFFSET); > > + Msr = SerialPortRead8 ((UINT16) gUartBase + > MSR_OFFSET); > > > > if ((Msr & MSR_CTS) == MSR_CTS) { > > *Control |= EFI_SERIAL_CLEAR_TO_SEND; @@ -318,7 > +380,7 @@ > > SerialPortGetControl ( > > // > > // Read the Modem Control Register. > > // > > - Mcr = IoRead8 ((UINT16) gUartBase + MCR_OFFSET); > > + Mcr = SerialPortRead8 ((UINT16) gUartBase + > MCR_OFFSET); > > > > if ((Mcr & MCR_DTRC) == MCR_DTRC) { > > *Control |= EFI_SERIAL_DATA_TERMINAL_READY; @@ - > 331,7 +393,7 @@ > > SerialPortGetControl ( > > // > > // Read the Line Status Register. > > // > > - Lsr = IoRead8 ((UINT16) gUartBase + LSR_OFFSET); > > + Lsr = SerialPortRead8 ((UINT16) gUartBase + > LSR_OFFSET); > > > > if ((Lsr & LSR_TXRDY) == LSR_TXRDY) { > > *Control |= EFI_SERIAL_OUTPUT_BUFFER_EMPTY; @@ - > 470,19 +532,19 @@ > > SerialPortSetAttributes ( > > // Set communications format > > // > > OutputData = (UINT8) ((DLAB << 7) | (gBreakSet << 6) > | (LcrParity > > << 3) | (LcrStop << 2) | LcrData); > > - IoWrite8 (gUartBase + LCR_OFFSET, OutputData); > > + SerialPortWrite8 (gUartBase + LCR_OFFSET, > OutputData); > > > > // > > // Configure baud rate > > // > > - IoWrite8 (gUartBase + BAUD_HIGH_OFFSET, (UINT8) > (Divisor >> 8)); > > - IoWrite8 (gUartBase + BAUD_LOW_OFFSET, (UINT8) > (Divisor & 0xff)); > > + SerialPortWrite8 (gUartBase + BAUD_HIGH_OFFSET, > (UINT8) (Divisor >> > > + 8)); > > + SerialPortWrite8 (gUartBase + BAUD_LOW_OFFSET, > (UINT8) (Divisor & > > + 0xff)); > > > > // > > // Switch back to bank 0 > > // > > OutputData = (UINT8) ((gBreakSet << 6) | (LcrParity > << 3) | > > (LcrStop << 2) | LcrData); > > - IoWrite8 (gUartBase + LCR_OFFSET, OutputData); > > + SerialPortWrite8 (gUartBase + LCR_OFFSET, > OutputData); > > > > return RETURN_SUCCESS; > > } > > -- > > 'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)' > > > > > _______________________________________________ > edk2-devel mailing list > [email protected] > https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
