[edk2 0/2] RISC-V SBI-backed SerialLib

[edk2 0/2] RISC-V SBI-backed SerialLib

[Andrei Warkentin]

Hello!

Here are two patches that give a SerialLib backed by
SBI console. Both legacy and DBCN mechanisms are
supported and have been tested (with UART and HTIF).

This is also available at https://github.com/andreiw/edk2-rv-wip/tree/patchset-2

Andrei Warkentin (2):
  MdePkg: BaseRiscVSbiLib: make more useful to consumers
  MdePkg: add BaseSerialPortLibRiscVSbi

 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.inf |  32 +++
 MdePkg/Include/Library/BaseRiscVSbiLib.h                               |  40 ++-
 MdePkg/Library/BaseRiscVSbiLib/BaseRiscVSbiLib.c                       |   3 +-
 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.c   | 260 ++++++++++++++++++++
 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.uni |  16 ++
 5 files changed, 346 insertions(+), 5 deletions(-)
 create mode 100644 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.inf
 create mode 100644 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.c
 create mode 100644 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.uni

-- 
2.25.1

[edk2 1/2] MdePkg: BaseRiscVSbiLib: make more useful to consumers

[Andrei Warkentin]

Add a few more definitions and make SbiCall and TranslateError
usable (not static) by library users.

Cc: Daniel Schaefer <git@danielschaefer.me>
Cc: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Andrei Warkentin <andrei.warkentin@intel.com>
---
 MdePkg/Include/Library/BaseRiscVSbiLib.h         | 40 ++++++++++++++++++--
 MdePkg/Library/BaseRiscVSbiLib/BaseRiscVSbiLib.c |  3 +-
 2 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/MdePkg/Include/Library/BaseRiscVSbiLib.h b/MdePkg/Include/Library/BaseRiscVSbiLib.h
index e75520b4b888..2244165a6b6a 100644
--- a/MdePkg/Include/Library/BaseRiscVSbiLib.h
+++ b/MdePkg/Include/Library/BaseRiscVSbiLib.h
@@ -2,6 +2,7 @@
   Library to call the RISC-V SBI ecalls
 
   Copyright (c) 2021-2022, Hewlett Packard Development LP. All rights reserved.<BR>
+  Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -18,10 +19,28 @@
 #include <Uefi.h>
 
 /* SBI Extension IDs */
-#define SBI_EXT_TIME  0x54494D45
-#define SBI_EXT_SRST  0x53525354
+#define SBI_EXT_0_1_CONSOLE_PUTCHAR  0x1
+#define SBI_EXT_0_1_CONSOLE_GETCHAR  0x2
+#define SBI_EXT_BASE                 0x10
+#define SBI_EXT_DBCN                 0x4442434E
+#define SBI_EXT_TIME                 0x54494D45
+#define SBI_EXT_SRST                 0x53525354
 
-/* SBI function IDs for TIME extension*/
+/* SBI function IDs for base extension */
+#define SBI_EXT_BASE_SPEC_VERSION   0x0
+#define SBI_EXT_BASE_IMPL_ID        0x1
+#define SBI_EXT_BASE_IMPL_VERSION   0x2
+#define SBI_EXT_BASE_PROBE_EXT      0x3
+#define SBI_EXT_BASE_GET_MVENDORID  0x4
+#define SBI_EXT_BASE_GET_MARCHID    0x5
+#define SBI_EXT_BASE_GET_MIMPID     0x6
+
+/* SBI function IDs for DBCN extension */
+#define SBI_EXT_DBCN_WRITE       0x0
+#define SBI_EXT_DBCN_READ        0x1
+#define SBI_EXT_DBCN_WRITE_BYTE  0x2
+
+/* SBI function IDs for TIME extension */
 #define SBI_EXT_TIME_SET_TIMER  0x0
 
 /* SBI function IDs for SRST extension */
@@ -62,6 +81,21 @@ typedef struct {
   UINTN    Value; ///< Value returned
 } SBI_RET;
 
+SBI_RET
+EFIAPI
+SbiCall (
+  IN  UINTN  ExtId,
+  IN  UINTN  FuncId,
+  IN  UINTN  NumArgs,
+  ...
+  );
+
+EFI_STATUS
+EFIAPI
+TranslateError (
+  IN  UINTN  SbiError
+  );
+
 VOID
 EFIAPI
 SbiSetTimer (
diff --git a/MdePkg/Library/BaseRiscVSbiLib/BaseRiscVSbiLib.c b/MdePkg/Library/BaseRiscVSbiLib/BaseRiscVSbiLib.c
index 2ba8f5ed366a..1141abfab9d0 100644
--- a/MdePkg/Library/BaseRiscVSbiLib/BaseRiscVSbiLib.c
+++ b/MdePkg/Library/BaseRiscVSbiLib/BaseRiscVSbiLib.c
@@ -4,6 +4,7 @@
   It allows calling an SBI function via an ecall from S-Mode.
 
   Copyright (c) 2021-2022, Hewlett Packard Development LP. All rights reserved.<BR>
+  Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -31,7 +32,6 @@
   @retval  Returns SBI_RET structure with value and error code.
 
 **/
-STATIC
 SBI_RET
 EFIAPI
 SbiCall (
@@ -88,7 +88,6 @@ SbiCall (
   @param[in] SbiError   SBI error code
   @retval EFI_STATUS
 **/
-STATIC
 EFI_STATUS
 EFIAPI
 TranslateError (
-- 
2.25.1

[edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Andrei Warkentin]

This is an implementation of SerialPortLib using SBI console services.

Tested with:
- Qemu RiscVVirt (non-DBCN case, backed by UART)
- TinyEMU + RiscVVirt (non-DBCN case, HTIF)
- TinyEMU + RiscVVirt (DBCN case, HTIF)

Cc: Daniel Schaefer <git@danielschaefer.me>
Cc: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Andrei Warkentin <andrei.warkentin@intel.com>
---
 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.inf |  32 +++
 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.c   | 260 ++++++++++++++++++++
 MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.uni |  16 ++
 3 files changed, 308 insertions(+)

diff --git a/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.inf b/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.inf
new file mode 100644
index 000000000000..70c8e48ea48e
--- /dev/null
+++ b/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.inf
@@ -0,0 +1,32 @@
+## @file
+#  Serial Port Library backed by SBI console.
+#
+#  Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = BaseSerialPortLibRiscVSbi
+  MODULE_UNI_FILE                = BaseSerialPortLibRiscVSbi.uni
+  FILE_GUID                      = E4541241-8897-4bba-91F8-7D7E45654346
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = SerialPortLib
+
+
+#
+#  VALID_ARCHITECTURES           = RISCV64
+#
+
+[Sources]
+  BaseSerialPortLibRiscVSbi.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+
+[LibraryClasses]
+  RiscVSbiLib
diff --git a/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.c b/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.c
new file mode 100644
index 000000000000..46bdf26fec71
--- /dev/null
+++ b/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.c
@@ -0,0 +1,260 @@
+/** @file
+  Serial Port Library backed by SBI console.
+
+  Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Base.h>
+#include <Library/SerialPortLib.h>
+#include <Library/BaseRiscVSbiLib.h>
+
+STATIC BOOLEAN  mHaveDbcn    = FALSE;
+STATIC INT64    mLastGetChar = -1;
+
+/**
+  Initialize the serial device hardware.
+
+  If no initialization is required, then return RETURN_SUCCESS.
+  If the serial device was successfully initialized, then return RETURN_SUCCESS.
+  If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.
+
+  @retval RETURN_SUCCESS        The serial device was initialized.
+  @retval RETURN_DEVICE_ERROR   The serial device could not be initialized.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortInitialize (
+  VOID
+  )
+{
+  SBI_RET  Ret;
+
+  Ret = SbiCall (SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, 1, SBI_EXT_DBCN);
+  if ((TranslateError (Ret.Error) == EFI_SUCCESS) &&
+      (Ret.Value != 0))
+  {
+    mHaveDbcn = TRUE;
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  Write data from buffer to serial device.
+
+  Writes NumberOfBytes data bytes from Buffer to the serial device.
+  The number of bytes actually written to the serial device is returned.
+  If the return value is less than NumberOfBytes, then the write operation failed.
+  If Buffer is NULL, then ASSERT().
+  If NumberOfBytes is zero, then return 0.
+
+  @param  Buffer           The pointer to the data buffer to be written.
+  @param  NumberOfBytes    The number of bytes to written to the serial device.
+
+  @retval 0                NumberOfBytes is 0.
+  @retval >0               The number of bytes written to the serial device.
+                           If this value is less than NumberOfBytes, then the write operation failed.
+
+**/
+UINTN
+EFIAPI
+SerialPortWrite (
+  IN UINT8  *Buffer,
+  IN UINTN  NumberOfBytes
+  )
+{
+  UINTN  Index;
+
+  if (mHaveDbcn) {
+    SBI_RET  Ret;
+    Ret = SbiCall (
+            SBI_EXT_DBCN,
+            SBI_EXT_DBCN_WRITE,
+            3,
+            NumberOfBytes,
+            ((UINTN)Buffer),
+            0
+            );
+    if (TranslateError (Ret.Error) != EFI_SUCCESS) {
+      return 0;
+    }
+
+    return Ret.Value;
+  }
+
+  for (Index = 0; Index < NumberOfBytes; Index++) {
+    SbiCall (SBI_EXT_0_1_CONSOLE_PUTCHAR, 0, 1, Buffer[Index]);
+  }
+
+  return Index;
+}
+
+/**
+  Read data from serial device and save the datas in buffer.
+
+  Reads NumberOfBytes data bytes from a serial device into the buffer
+  specified by Buffer. The number of bytes actually read is returned.
+  If the return value is less than NumberOfBytes, then the rest operation failed.
+  If Buffer is NULL, then ASSERT().
+  If NumberOfBytes is zero, then return 0.
+
+  @param  Buffer           The pointer to the data buffer to store the data read from the serial device.
+  @param  NumberOfBytes    The number of bytes which will be read.
+
+  @retval 0                Read data failed; No data is to be read.
+  @retval >0               The actual number of bytes read from serial device.
+
+**/
+UINTN
+EFIAPI
+SerialPortRead (
+  OUT UINT8  *Buffer,
+  IN  UINTN  NumberOfBytes
+  )
+{
+  UINTN  Index = 0;
+
+  while ((Index < NumberOfBytes) && SerialPortPoll ()) {
+    Buffer[Index++] = (UINT8)mLastGetChar;
+    mLastGetChar    = -1;
+  }
+
+  return Index;
+}
+
+/**
+  Polls a serial device to see if there is any data waiting to be read.
+
+  Polls a serial device to see if there is any data waiting to be read.
+  If there is data waiting to be read from the serial device, then TRUE is returned.
+  If there is no data waiting to be read from the serial device, then FALSE is returned.
+
+  @retval TRUE             Data is waiting to be read from the serial device.
+  @retval FALSE            There is no data waiting to be read from the serial device.
+
+**/
+BOOLEAN
+EFIAPI
+SerialPortPoll (
+  VOID
+  )
+{
+  /*
+   * Careful. OpenSBI with HTIF console will return -1 followed by -2
+   * if there is no character received. So just check for values >= 0.
+   */
+
+  if (mLastGetChar >= 0) {
+    return TRUE;
+  }
+
+  if (mHaveDbcn) {
+    UINT8    Buffer;
+    SBI_RET  Ret = SbiCall (
+                     SBI_EXT_DBCN,
+                     SBI_EXT_DBCN_READ,
+                     3,
+                     1,
+                     ((UINTN)&Buffer),
+                     0
+                     );
+    if ((TranslateError (Ret.Error) == EFI_SUCCESS) &&
+        (Ret.Value == 1))
+    {
+      mLastGetChar = Buffer;
+    }
+  } else {
+    mLastGetChar = (INT64)SbiCall (SBI_EXT_0_1_CONSOLE_GETCHAR, 0, 0).Error;
+  }
+
+  return mLastGetChar >= 0;
+}
+
+/**
+  Sets the control bits on a serial device.
+
+  @param Control                Sets the bits of Control that are settable.
+
+  @retval RETURN_SUCCESS        The new control bits were set on the serial device.
+  @retval RETURN_UNSUPPORTED    The serial device does not support this operation.
+  @retval RETURN_DEVICE_ERROR   The serial device is not functioning correctly.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortSetControl (
+  IN UINT32  Control
+  )
+{
+  return RETURN_SUCCESS;
+}
+
+/**
+  Retrieve the status of the control bits on a serial device.
+
+  @param Control                A pointer to return the current control signals from the serial device.
+
+  @retval RETURN_SUCCESS        The control bits were read from the serial device.
+  @retval RETURN_UNSUPPORTED    The serial device does not support this operation.
+  @retval RETURN_DEVICE_ERROR   The serial device is not functioning correctly.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortGetControl (
+  OUT UINT32  *Control
+  )
+{
+  *Control = 0;
+  return RETURN_SUCCESS;
+}
+
+/**
+  Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,
+  data bits, and stop bits on a serial device.
+
+  @param BaudRate           The requested baud rate. A BaudRate value of 0 will use the
+                            device's default interface speed.
+                            On output, the value actually set.
+  @param ReveiveFifoDepth   The requested depth of the FIFO on the receive side of the
+                            serial interface. A ReceiveFifoDepth value of 0 will use
+                            the device's default FIFO depth.
+                            On output, the value actually set.
+  @param Timeout            The requested time out for a single character in microseconds.
+                            This timeout applies to both the transmit and receive side of the
+                            interface. A Timeout value of 0 will use the device's default time
+                            out value.
+                            On output, the value actually set.
+  @param Parity             The type of parity to use on this serial device. A Parity value of
+                            DefaultParity will use the device's default parity value.
+                            On output, the value actually set.
+  @param DataBits           The number of data bits to use on the serial device. A DataBits
+                            vaule of 0 will use the device's default data bit setting.
+                            On output, the value actually set.
+  @param StopBits           The number of stop bits to use on this serial device. A StopBits
+                            value of DefaultStopBits will use the device's default number of
+                            stop bits.
+                            On output, the value actually set.
+
+  @retval RETURN_SUCCESS            The new attributes were set on the serial device.
+  @retval RETURN_UNSUPPORTED        The serial device does not support this operation.
+  @retval RETURN_INVALID_PARAMETER  One or more of the attributes has an unsupported value.
+  @retval RETURN_DEVICE_ERROR       The serial device is not functioning correctly.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortSetAttributes (
+  IN OUT UINT64              *BaudRate,
+  IN OUT UINT32              *ReceiveFifoDepth,
+  IN OUT UINT32              *Timeout,
+  IN OUT EFI_PARITY_TYPE     *Parity,
+  IN OUT UINT8               *DataBits,
+  IN OUT EFI_STOP_BITS_TYPE  *StopBits
+  )
+{
+  return RETURN_SUCCESS;
+}
diff --git a/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.uni b/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.uni
new file mode 100644
index 000000000000..7b22caa5a090
--- /dev/null
+++ b/MdePkg/Library/BaseSerialPortLibRiscVSbi/BaseSerialPortLibRiscVSbi.uni
@@ -0,0 +1,16 @@
+// /** @file
+// Serial Port Library backed by SBI console.
+//
+// Serial Port Library backed by SBI console.
+//
+// Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+// **/
+
+
+#string STR_MODULE_ABSTRACT             #language en-US "Serial Port Library backed by SBI console"
+
+#string STR_MODULE_DESCRIPTION          #language en-US "Serial Port Library backed by SBI console."
+
-- 
2.25.1

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Gerd Hoffmann]

  Hi,

> +  while ((Index < NumberOfBytes) && SerialPortPoll ()) {
> +    Buffer[Index++] = (UINT8)mLastGetChar;
> +    mLastGetChar    = -1;
> +  }

Why do you use a global variable to pass the character?  SerialPortPoll
could just return it directly ...

take care,
  Gerd

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Andrei Warkentin]

[-- Attachment #1: Type: text/plain, Size: 1078 bytes --]

The library caller could call Poll() first, then call Read(), and the expectation is the char won't be lost. SBI doesn't have a poll call itself, so best you could do is read and stash. So you have to stash it globally. And read must use the stashed char, if it exists, before requesting more data from SBI. At that point, reading is easy to treat as continued polling - just to keep the code simple.

A
________________________________
От: Gerd Hoffmann <kraxel@redhat.com>
Отправлено: Wednesday, March 1, 2023 2:13:32 AM
Кому: devel@edk2.groups.io <devel@edk2.groups.io>; Warkentin, Andrei <andrei.warkentin@intel.com>
Копия: Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>
Тема: Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

  Hi,

> +  while ((Index < NumberOfBytes) && SerialPortPoll ()) {
> +    Buffer[Index++] = (UINT8)mLastGetChar;
> +    mLastGetChar    = -1;
> +  }

Why do you use a global variable to pass the character?  SerialPortPoll
could just return it directly ...

take care,
  Gerd


[-- Attachment #2: Type: text/html, Size: 1901 bytes --]

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Gerd Hoffmann]

On Wed, Mar 01, 2023 at 08:50:38AM +0000, Warkentin, Andrei wrote:
> The library caller could call Poll() first,

Ah, Poll is part of the library API, not just an internal helper.
Ok, makes sense then.

series:
Acked-by: Gerd Hoffmann <kraxel@redhat.com>

take care,
  Gerd

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Michael D Kinney]

Using a global is not compatible with XIP code where only const globals are supported.

A module of type BASE is considered compatible with XIP components.


Mike

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Gerd Hoffmann
> Sent: Wednesday, March 1, 2023 1:07 AM
> To: Warkentin, Andrei <andrei.warkentin@intel.com>
> Cc: devel@edk2.groups.io; Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>
> Subject: Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi
> 
> On Wed, Mar 01, 2023 at 08:50:38AM +0000, Warkentin, Andrei wrote:
> > The library caller could call Poll() first,
> 
> Ah, Poll is part of the library API, not just an internal helper.
> Ok, makes sense then.
> 
> series:
> Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> 
> take care,
>   Gerd
> 
> 
> 
> 
> 

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Andrei Warkentin]

Hi Michael,

What module type should I use instead? The reason being this SerialPortLib implementation specifically fits into the class of UEFI implementations, where RAM is always available (initialized by something else prior to Tiano) and non-const globals can be used (e.g. PrePi).

A

-----Original Message-----
From: Kinney, Michael D <michael.d.kinney@intel.com> 
Sent: Wednesday, March 1, 2023 10:56 AM
To: devel@edk2.groups.io; kraxel@redhat.com; Warkentin, Andrei <andrei.warkentin@intel.com>
Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

Using a global is not compatible with XIP code where only const globals are supported.

A module of type BASE is considered compatible with XIP components.


Mike

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Gerd Hoffmann
> Sent: Wednesday, March 1, 2023 1:07 AM
> To: Warkentin, Andrei <andrei.warkentin@intel.com>
> Cc: devel@edk2.groups.io; Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>
> Subject: Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi
> 
> On Wed, Mar 01, 2023 at 08:50:38AM +0000, Warkentin, Andrei wrote:
> > The library caller could call Poll() first,
> 
> Ah, Poll is part of the library API, not just an internal helper.
> Ok, makes sense then.
> 
> series:
> Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> 
> take care,
>   Gerd
> 
> 
> 
> 
> 

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Michael D Kinney]

If a dependency on MdePkg\Include\Library\ BaseRiscVSbiLib.h and SBI services assumed memory is available
and code loaded is loaded into RAM and not XIP, then BASE is ok for this component.

You may want to make sure the library class header file and INF file header for BaseRiscVSbiLib 
describe that environment assumption and the INF for BaseSerialPortLibRiscVSbi also 
describes that environment assumption.

Mike

> -----Original Message-----
> From: Warkentin, Andrei <andrei.warkentin@intel.com>
> Sent: Wednesday, March 1, 2023 9:26 AM
> To: Kinney, Michael D <michael.d.kinney@intel.com>; devel@edk2.groups.io; kraxel@redhat.com
> Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>
> Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi
> 
> Hi Michael,
> 
> What module type should I use instead? The reason being this SerialPortLib implementation specifically fits into the class of
> UEFI implementations, where RAM is always available (initialized by something else prior to Tiano) and non-const globals can be
> used (e.g. PrePi).
> 
> A
> 
> -----Original Message-----
> From: Kinney, Michael D <michael.d.kinney@intel.com>
> Sent: Wednesday, March 1, 2023 10:56 AM
> To: devel@edk2.groups.io; kraxel@redhat.com; Warkentin, Andrei <andrei.warkentin@intel.com>
> Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>; Kinney, Michael D
> <michael.d.kinney@intel.com>
> Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi
> 
> Using a global is not compatible with XIP code where only const globals are supported.
> 
> A module of type BASE is considered compatible with XIP components.
> 
> 
> Mike
> 
> > -----Original Message-----
> > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Gerd Hoffmann
> > Sent: Wednesday, March 1, 2023 1:07 AM
> > To: Warkentin, Andrei <andrei.warkentin@intel.com>
> > Cc: devel@edk2.groups.io; Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>
> > Subject: Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi
> >
> > On Wed, Mar 01, 2023 at 08:50:38AM +0000, Warkentin, Andrei wrote:
> > > The library caller could call Poll() first,
> >
> > Ah, Poll is part of the library API, not just an internal helper.
> > Ok, makes sense then.
> >
> > series:
> > Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> >
> > take care,
> >   Gerd
> >
> >
> >
> > 
> >

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Andrei Warkentin]

Thanks... let me go a different route.

I'll have 1 more variant that can be used in classical SEC and PEI - only capable of output (input doesn't matter) and rename the one I already shared.  I'll name these SecPeiSerialPortLibRiscVSbi and PrePiDxeSerialPortLibRiscVSbi, respectively.

Does this sound acceptable?

-----Original Message-----
From: Kinney, Michael D <michael.d.kinney@intel.com> 
Sent: Wednesday, March 1, 2023 11:51 AM
To: Warkentin, Andrei <andrei.warkentin@intel.com>; devel@edk2.groups.io; kraxel@redhat.com
Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

If a dependency on MdePkg\Include\Library\ BaseRiscVSbiLib.h and SBI services assumed memory is available and code loaded is loaded into RAM and not XIP, then BASE is ok for this component.

You may want to make sure the library class header file and INF file header for BaseRiscVSbiLib describe that environment assumption and the INF for BaseSerialPortLibRiscVSbi also describes that environment assumption.

Mike

> -----Original Message-----
> From: Warkentin, Andrei <andrei.warkentin@intel.com>
> Sent: Wednesday, March 1, 2023 9:26 AM
> To: Kinney, Michael D <michael.d.kinney@intel.com>; 
> devel@edk2.groups.io; kraxel@redhat.com
> Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L 
> <sunilvl@ventanamicro.com>
> Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add 
> BaseSerialPortLibRiscVSbi
> 
> Hi Michael,
> 
> What module type should I use instead? The reason being this 
> SerialPortLib implementation specifically fits into the class of UEFI 
> implementations, where RAM is always available (initialized by something else prior to Tiano) and non-const globals can be used (e.g. PrePi).
> 
> A
> 
> -----Original Message-----
> From: Kinney, Michael D <michael.d.kinney@intel.com>
> Sent: Wednesday, March 1, 2023 10:56 AM
> To: devel@edk2.groups.io; kraxel@redhat.com; Warkentin, Andrei 
> <andrei.warkentin@intel.com>
> Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L 
> <sunilvl@ventanamicro.com>; Kinney, Michael D 
> <michael.d.kinney@intel.com>
> Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add 
> BaseSerialPortLibRiscVSbi
> 
> Using a global is not compatible with XIP code where only const globals are supported.
> 
> A module of type BASE is considered compatible with XIP components.
> 
> 
> Mike
> 
> > -----Original Message-----
> > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Gerd 
> > Hoffmann
> > Sent: Wednesday, March 1, 2023 1:07 AM
> > To: Warkentin, Andrei <andrei.warkentin@intel.com>
> > Cc: devel@edk2.groups.io; Daniel Schaefer <git@danielschaefer.me>; 
> > Sunil V L <sunilvl@ventanamicro.com>
> > Subject: Re: [edk2-devel] [edk2 2/2] MdePkg: add 
> > BaseSerialPortLibRiscVSbi
> >
> > On Wed, Mar 01, 2023 at 08:50:38AM +0000, Warkentin, Andrei wrote:
> > > The library caller could call Poll() first,
> >
> > Ah, Poll is part of the library API, not just an internal helper.
> > Ok, makes sense then.
> >
> > series:
> > Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> >
> > take care,
> >   Gerd
> >
> >
> >
> > 
> >

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Sunil V L]

Hi Andrei,

It is not just mLastGetChar but mHaveDbcn also will have the same issue
with XIP. So, I am wondering why not probe for the extension in every write
for the SecPei case? I understand the performance concerns but does it really
matter for debug output? I believe it is minor compared to the
flexibility it provides for not having a fixed serial port
implementation.

Thanks,
Sunil

On Wed, Mar 01, 2023 at 05:56:36PM +0000, Andrei Warkentin wrote:
> Thanks... let me go a different route.
> 
> I'll have 1 more variant that can be used in classical SEC and PEI - only capable of output (input doesn't matter) and rename the one I already shared.  I'll name these SecPeiSerialPortLibRiscVSbi and PrePiDxeSerialPortLibRiscVSbi, respectively.
> 
> Does this sound acceptable?
> 
> -----Original Message-----
> From: Kinney, Michael D <michael.d.kinney@intel.com> 
> Sent: Wednesday, March 1, 2023 11:51 AM
> To: Warkentin, Andrei <andrei.warkentin@intel.com>; devel@edk2.groups.io; kraxel@redhat.com
> Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>; Kinney, Michael D <michael.d.kinney@intel.com>
> Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi
> 
> If a dependency on MdePkg\Include\Library\ BaseRiscVSbiLib.h and SBI services assumed memory is available and code loaded is loaded into RAM and not XIP, then BASE is ok for this component.
> 
> You may want to make sure the library class header file and INF file header for BaseRiscVSbiLib describe that environment assumption and the INF for BaseSerialPortLibRiscVSbi also describes that environment assumption.
> 
> Mike
> 
> > -----Original Message-----
> > From: Warkentin, Andrei <andrei.warkentin@intel.com>
> > Sent: Wednesday, March 1, 2023 9:26 AM
> > To: Kinney, Michael D <michael.d.kinney@intel.com>; 
> > devel@edk2.groups.io; kraxel@redhat.com
> > Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L 
> > <sunilvl@ventanamicro.com>
> > Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add 
> > BaseSerialPortLibRiscVSbi
> > 
> > Hi Michael,
> > 
> > What module type should I use instead? The reason being this 
> > SerialPortLib implementation specifically fits into the class of UEFI 
> > implementations, where RAM is always available (initialized by something else prior to Tiano) and non-const globals can be used (e.g. PrePi).
> > 
> > A
> > 
> > -----Original Message-----
> > From: Kinney, Michael D <michael.d.kinney@intel.com>
> > Sent: Wednesday, March 1, 2023 10:56 AM
> > To: devel@edk2.groups.io; kraxel@redhat.com; Warkentin, Andrei 
> > <andrei.warkentin@intel.com>
> > Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L 
> > <sunilvl@ventanamicro.com>; Kinney, Michael D 
> > <michael.d.kinney@intel.com>
> > Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add 
> > BaseSerialPortLibRiscVSbi
> > 
> > Using a global is not compatible with XIP code where only const globals are supported.
> > 
> > A module of type BASE is considered compatible with XIP components.
> > 
> > 
> > Mike
> > 
> > > -----Original Message-----
> > > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Gerd 
> > > Hoffmann
> > > Sent: Wednesday, March 1, 2023 1:07 AM
> > > To: Warkentin, Andrei <andrei.warkentin@intel.com>
> > > Cc: devel@edk2.groups.io; Daniel Schaefer <git@danielschaefer.me>; 
> > > Sunil V L <sunilvl@ventanamicro.com>
> > > Subject: Re: [edk2-devel] [edk2 2/2] MdePkg: add 
> > > BaseSerialPortLibRiscVSbi
> > >
> > > On Wed, Mar 01, 2023 at 08:50:38AM +0000, Warkentin, Andrei wrote:
> > > > The library caller could call Poll() first,
> > >
> > > Ah, Poll is part of the library API, not just an internal helper.
> > > Ok, makes sense then.
> > >
> > > series:
> > > Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> > >
> > > take care,
> > >   Gerd
> > >
> > >
> > >
> > > 
> > >
> 
> 
> 
> 
> 
> 

Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

[Andrei Warkentin]

[-- Attachment #1: Type: text/plain, Size: 4520 bytes --]

That's exactly what I did. The SecPei variant has no globals and always probes (but can't read, only writes)

Will send an updated patch set later today.

A
________________________________
От: Sunil V L <sunilvl@ventanamicro.com>
Отправлено: четверг, марта 2, 2023 4:35 AM
Кому: devel@edk2.groups.io <devel@edk2.groups.io>; Warkentin, Andrei <andrei.warkentin@intel.com>
Копия: Kinney, Michael D <michael.d.kinney@intel.com>; kraxel@redhat.com <kraxel@redhat.com>; Daniel Schaefer <git@danielschaefer.me>
Тема: Re: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi

Hi Andrei,

It is not just mLastGetChar but mHaveDbcn also will have the same issue
with XIP. So, I am wondering why not probe for the extension in every write
for the SecPei case? I understand the performance concerns but does it really
matter for debug output? I believe it is minor compared to the
flexibility it provides for not having a fixed serial port
implementation.

Thanks,
Sunil

On Wed, Mar 01, 2023 at 05:56:36PM +0000, Andrei Warkentin wrote:
> Thanks... let me go a different route.
>
> I'll have 1 more variant that can be used in classical SEC and PEI - only capable of output (input doesn't matter) and rename the one I already shared.  I'll name these SecPeiSerialPortLibRiscVSbi and PrePiDxeSerialPortLibRiscVSbi, respectively.
>
> Does this sound acceptable?
>
> -----Original Message-----
> From: Kinney, Michael D <michael.d.kinney@intel.com>
> Sent: Wednesday, March 1, 2023 11:51 AM
> To: Warkentin, Andrei <andrei.warkentin@intel.com>; devel@edk2.groups.io; kraxel@redhat.com
> Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L <sunilvl@ventanamicro.com>; Kinney, Michael D <michael.d.kinney@intel.com>
> Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add BaseSerialPortLibRiscVSbi
>
> If a dependency on MdePkg\Include\Library\ BaseRiscVSbiLib.h and SBI services assumed memory is available and code loaded is loaded into RAM and not XIP, then BASE is ok for this component.
>
> You may want to make sure the library class header file and INF file header for BaseRiscVSbiLib describe that environment assumption and the INF for BaseSerialPortLibRiscVSbi also describes that environment assumption.
>
> Mike
>
> > -----Original Message-----
> > From: Warkentin, Andrei <andrei.warkentin@intel.com>
> > Sent: Wednesday, March 1, 2023 9:26 AM
> > To: Kinney, Michael D <michael.d.kinney@intel.com>;
> > devel@edk2.groups.io; kraxel@redhat.com
> > Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L
> > <sunilvl@ventanamicro.com>
> > Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add
> > BaseSerialPortLibRiscVSbi
> >
> > Hi Michael,
> >
> > What module type should I use instead? The reason being this
> > SerialPortLib implementation specifically fits into the class of UEFI
> > implementations, where RAM is always available (initialized by something else prior to Tiano) and non-const globals can be used (e.g. PrePi).
> >
> > A
> >
> > -----Original Message-----
> > From: Kinney, Michael D <michael.d.kinney@intel.com>
> > Sent: Wednesday, March 1, 2023 10:56 AM
> > To: devel@edk2.groups.io; kraxel@redhat.com; Warkentin, Andrei
> > <andrei.warkentin@intel.com>
> > Cc: Daniel Schaefer <git@danielschaefer.me>; Sunil V L
> > <sunilvl@ventanamicro.com>; Kinney, Michael D
> > <michael.d.kinney@intel.com>
> > Subject: RE: [edk2-devel] [edk2 2/2] MdePkg: add
> > BaseSerialPortLibRiscVSbi
> >
> > Using a global is not compatible with XIP code where only const globals are supported.
> >
> > A module of type BASE is considered compatible with XIP components.
> >
> >
> > Mike
> >
> > > -----Original Message-----
> > > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Gerd
> > > Hoffmann
> > > Sent: Wednesday, March 1, 2023 1:07 AM
> > > To: Warkentin, Andrei <andrei.warkentin@intel.com>
> > > Cc: devel@edk2.groups.io; Daniel Schaefer <git@danielschaefer.me>;
> > > Sunil V L <sunilvl@ventanamicro.com>
> > > Subject: Re: [edk2-devel] [edk2 2/2] MdePkg: add
> > > BaseSerialPortLibRiscVSbi
> > >
> > > On Wed, Mar 01, 2023 at 08:50:38AM +0000, Warkentin, Andrei wrote:
> > > > The library caller could call Poll() first,
> > >
> > > Ah, Poll is part of the library API, not just an internal helper.
> > > Ok, makes sense then.
> > >
> > > series:
> > > Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> > >
> > > take care,
> > >   Gerd
> > >
> > >
> > >
> > >
> > >
>
>
>
> 
>
>

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