-----Original Message-----
From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Sunil V L
Sent: Sunday, January 29, 2023 3:18 AM
To: devel@edk2.groups.io
Cc: Dong, Eric <eric.dong@...>; Ni, Ray <ray.ni@...>; Kumar,
Rahul R <rahul.r.kumar@...>; Daniel Schaefer
<git@...>; Abner Chang <abner.chang@...>; Gerd
Hoffmann <kraxel@...>
Subject: [edk2-devel] [edk2-staging/RiscV64QemuVirt PATCH V7 06/20]
UefiCpuPkg/CpuExceptionHandlerLib: Add RISC-V instance

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4076

Add Cpu Exception Handler library for RISC-V. This is copied
from edk2-platforms/Silicon/RISC-V/ProcessorPkg/Library/RiscVExceptionLib

Cc: Eric Dong <eric.dong@...>
Cc: Ray Ni <ray.ni@...>
Cc: Rahul Kumar <rahul1.kumar@...>
Cc: Daniel Schaefer <git@...>
Cc: Abner Chang <abner.chang@...>
Cc: Gerd Hoffmann <kraxel@...>
Signed-off-by: Sunil V L <sunilvl@...>
Acked-by: Abner Chang <abner.chang@...>
---
UefiCpuPkg/UefiCpuPkg.dsc | 1 +

UefiCpuPkg/Library/CpuExceptionHandlerLib/BaseRiscV64CpuExceptionHan
dlerLib.inf | 42 +++++++

UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerL
ib.h | 116 +++++++++++++++++

UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerL
ib.c | 133 ++++++++++++++++++++

UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/SupervisorTrapHandle
r.S | 105 ++++++++++++++++
5 files changed, 397 insertions(+)

diff --git a/UefiCpuPkg/UefiCpuPkg.dsc b/UefiCpuPkg/UefiCpuPkg.dsc
index 96f6770281fe..251a8213f022 100644
--- a/UefiCpuPkg/UefiCpuPkg.dsc
+++ b/UefiCpuPkg/UefiCpuPkg.dsc
@@ -197,6 +197,7 @@ [Components.X64]

[Components.RISCV64]
UefiCpuPkg/CpuTimerDxe/CpuTimerDxe.inf
+
UefiCpuPkg/Library/CpuExceptionHandlerLib/BaseRiscV64CpuExceptionHan
dlerLib.inf

[BuildOptions]
*_*_*_CC_FLAGS = -D DISABLE_NEW_DEPRECATED_INTERFACES
diff --git
a/UefiCpuPkg/Library/CpuExceptionHandlerLib/BaseRiscV64CpuExceptionHa
ndlerLib.inf
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/BaseRiscV64CpuExceptionHa
ndlerLib.inf
new file mode 100644
index 000000000000..82ca22c4bfec
--- /dev/null
+++
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/BaseRiscV64CpuExceptionHa
ndlerLib.inf
@@ -0,0 +1,42 @@
+## @file
+# RISC-V CPU Exception Handler Library
+#
+# Copyright (c) 2022, Ventana Micro Systems Inc. All rights reserved.<BR>
+#
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+ INF_VERSION = 0x0001001B
+ BASE_NAME = BaseRiscV64CpuExceptionHandlerLib
+ MODULE_UNI_FILE = BaseRiscV64CpuExceptionHandlerLib.uni
+ FILE_GUID = 6AB0D5FD-E615-45A3-9374-E284FB061FC9
+ MODULE_TYPE = BASE
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = CpuExceptionHandlerLib
+
+#
+# The following information is for reference only and not required by the
build tools.
+#
+# VALID_ARCHITECTURES = RISCV64
+#
+
+[Sources]
+ RiscV64/SupervisorTrapHandler.S
+ RiscV64/CpuExceptionHandlerLib.c
+ RiscV64/CpuExceptionHandlerLib.h
+
+[Packages]
+ MdePkg/MdePkg.dec
+ MdeModulePkg/MdeModulePkg.dec
+ UefiCpuPkg/UefiCpuPkg.dec
+
+[LibraryClasses]
+ BaseLib
+ SerialPortLib
+ PrintLib
+ SynchronizationLib
+ PeCoffGetEntryPointLib
+ MemoryAllocationLib
+ DebugLib
diff --git
a/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandl
erLib.h
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandl
erLib.h
new file mode 100644
index 000000000000..30f47e87552b
--- /dev/null
+++
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandl
erLib.h
@@ -0,0 +1,116 @@
+/** @file
+
+ RISC-V Exception Handler library definition file.
+
+ Copyright (c) 2019-2022, Hewlett Packard Enterprise Development LP. All
rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef RISCV_CPU_EXECPTION_HANDLER_LIB_H_
+#define RISCV_CPU_EXECPTION_HANDLER_LIB_H_
+
+#include <Register/RiscV64/RiscVImpl.h>
+
+/**
+ Trap Handler for S-mode
+
+**/
+VOID
+SupervisorModeTrap (
+ VOID
+ );
+
+//
+// Index of SMode trap register
+//
+#define SMODE_TRAP_REGS_zero 0
+#define SMODE_TRAP_REGS_ra 1
+#define SMODE_TRAP_REGS_sp 2
+#define SMODE_TRAP_REGS_gp 3
+#define SMODE_TRAP_REGS_tp 4
+#define SMODE_TRAP_REGS_t0 5
+#define SMODE_TRAP_REGS_t1 6
+#define SMODE_TRAP_REGS_t2 7
+#define SMODE_TRAP_REGS_s0 8
+#define SMODE_TRAP_REGS_s1 9
+#define SMODE_TRAP_REGS_a0 10
+#define SMODE_TRAP_REGS_a1 11
+#define SMODE_TRAP_REGS_a2 12
+#define SMODE_TRAP_REGS_a3 13
+#define SMODE_TRAP_REGS_a4 14
+#define SMODE_TRAP_REGS_a5 15
+#define SMODE_TRAP_REGS_a6 16
+#define SMODE_TRAP_REGS_a7 17
+#define SMODE_TRAP_REGS_s2 18
+#define SMODE_TRAP_REGS_s3 19
+#define SMODE_TRAP_REGS_s4 20
+#define SMODE_TRAP_REGS_s5 21
+#define SMODE_TRAP_REGS_s6 22
+#define SMODE_TRAP_REGS_s7 23
+#define SMODE_TRAP_REGS_s8 24
+#define SMODE_TRAP_REGS_s9 25
+#define SMODE_TRAP_REGS_s10 26
+#define SMODE_TRAP_REGS_s11 27
+#define SMODE_TRAP_REGS_t3 28
+#define SMODE_TRAP_REGS_t4 29
+#define SMODE_TRAP_REGS_t5 30
+#define SMODE_TRAP_REGS_t6 31
+#define SMODE_TRAP_REGS_sepc 32
+#define SMODE_TRAP_REGS_sstatus 33
+#define SMODE_TRAP_REGS_sie 34
+#define SMODE_TRAP_REGS_last 35
+
+#define SMODE_TRAP_REGS_OFFSET(x) ((SMODE_TRAP_REGS_##x) *
__SIZEOF_POINTER__)
+#define SMODE_TRAP_REGS_SIZE SMODE_TRAP_REGS_OFFSET(last)
+
+#pragma pack(1)
+typedef struct {
+ //
+ // Below are follow the format of EFI_SYSTEM_CONTEXT
+ //
+ UINT64 zero;
+ UINT64 ra;
+ UINT64 sp;
+ UINT64 gp;
+ UINT64 tp;
+ UINT64 t0;
+ UINT64 t1;
+ UINT64 t2;
+ UINT64 s0;
+ UINT64 s1;
+ UINT64 a0;
+ UINT64 a1;
+ UINT64 a2;
+ UINT64 a3;
+ UINT64 a4;
+ UINT64 a5;
+ UINT64 a6;
+ UINT64 a7;
+ UINT64 s2;
+ UINT64 s3;
+ UINT64 s4;
+ UINT64 s5;
+ UINT64 s6;
+ UINT64 s7;
+ UINT64 s8;
+ UINT64 s9;
+ UINT64 s10;
+ UINT64 s11;
+ UINT64 t3;
+ UINT64 t4;
+ UINT64 t5;
+ UINT64 t6;
+ //
+ // Below are the additional information to
+ // EFI_SYSTEM_CONTEXT, private to supervisor mode trap
+ // and not public to EFI environment.
+ //
+ UINT64 sepc;
+ UINT64 sstatus;
+ UINT64 sie;
+} SMODE_TRAP_REGISTERS;
+#pragma pack()
+
+#endif
diff --git
a/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandl
erLib.c
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandl
erLib.c
new file mode 100644
index 000000000000..f1ee7d236aec
--- /dev/null
+++
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandl
erLib.c
@@ -0,0 +1,133 @@
+/** @file
+ RISC-V Exception Handler library implementation.
+
+ Copyright (c) 2016 - 2022, Hewlett Packard Enterprise Development LP. All
rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiPei.h>
+#include <Library/CpuExceptionHandlerLib.h>
+#include <Library/DebugLib.h>
+#include <Library/BaseLib.h>
+#include <Register/RiscV64/RiscVEncoding.h>
+
+#include "CpuExceptionHandlerLib.h"
+
+STATIC EFI_CPU_INTERRUPT_HANDLER mInterruptHandlers[2];
+
+/**
+ Initializes all CPU exceptions entries and provides the default exception
handlers.
+
+ Caller should try to get an array of interrupt and/or exception vectors that
are in use and need to
+ persist by EFI_VECTOR_HANDOFF_INFO defined in PI 1.3 specification.
+ If caller cannot get reserved vector list or it does not exists, set VectorInfo
to NULL.
+ If VectorInfo is not NULL, the exception vectors will be initialized per
vector attribute accordingly.
+
+ @param[in] VectorInfo Pointer to reserved vector list.
+
+ @retval EFI_SUCCESS CPU Exception Entries have been successfully
initialized
+ with default exception handlers.
+ @retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content
if VectorInfo is not NULL.
+ @retval EFI_UNSUPPORTED This function is not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+InitializeCpuExceptionHandlers (
+ IN EFI_VECTOR_HANDOFF_INFO *VectorInfo OPTIONAL
+ )
+{
+ RiscVSetSupervisorStvec ((UINT64)SupervisorModeTrap);
+ return EFI_SUCCESS;
+}
+
+/**
+ Registers a function to be called from the processor interrupt handler.
+
+ This function registers and enables the handler specified by
InterruptHandler for a processor
+ interrupt or exception type specified by InterruptType. If InterruptHandler
is NULL, then the
+ handler for the processor interrupt or exception type specified by
InterruptType is uninstalled.
+ The installed handler is called once for each processor interrupt or
exception.
+ NOTE: This function should be invoked after
InitializeCpuExceptionHandlers() or
+ InitializeCpuInterruptHandlers() invoked, otherwise EFI_UNSUPPORTED
returned.
+
+ @param[in] InterruptType Defines which interrupt or exception to hook.
+ @param[in] InterruptHandler A pointer to a function of type
EFI_CPU_INTERRUPT_HANDLER that is called
+ when a processor interrupt occurs. If this parameter is NULL,
then the handler
+ will be uninstalled.
+
+ @retval EFI_SUCCESS The handler for the processor interrupt was
successfully installed or uninstalled.
+ @retval EFI_ALREADY_STARTED InterruptHandler is not NULL, and a
handler for InterruptType was
+ previously installed.
+ @retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler
for InterruptType was not
+ previously installed.
+ @retval EFI_UNSUPPORTED The interrupt specified by InterruptType is
not supported,
+ or this function is not supported.
+**/
+EFI_STATUS
+EFIAPI
+RegisterCpuInterruptHandler (
+ IN EFI_EXCEPTION_TYPE InterruptType,
+ IN EFI_CPU_INTERRUPT_HANDLER InterruptHandler
+ )
+{
+ DEBUG ((DEBUG_INFO, "%a: Type:%x Handler: %x\n", __FUNCTION__,
InterruptType, InterruptHandler));
+ mInterruptHandlers[InterruptType] = InterruptHandler;
+ return EFI_SUCCESS;
+}
+
+/**
+ Setup separate stacks for certain exception handlers.
+ If the input Buffer and BufferSize are both NULL, use global variable if
possible.
+
+ @param[in] Buffer Point to buffer used to separate exception stack.
+ @param[in, out] BufferSize On input, it indicates the byte size of Buffer.
+ If the size is not enough, the return status will
+ be EFI_BUFFER_TOO_SMALL, and output BufferSize
+ will be the size it needs.
+
+ @retval EFI_SUCCESS The stacks are assigned successfully.
+ @retval EFI_UNSUPPORTED This function is not supported.
+ @retval EFI_BUFFER_TOO_SMALL This BufferSize is too small.
+**/
+EFI_STATUS
+EFIAPI
+InitializeSeparateExceptionStacks (
+ IN VOID *Buffer,
+ IN OUT UINTN *BufferSize
+ )
+{
+ return EFI_SUCCESS;
+}
+
+/**
+ Supervisor mode trap handler.
+
+ @param[in] SmodeTrapReg Registers before trap occurred.
+
+**/
+VOID
+RiscVSupervisorModeTrapHandler (
+ SMODE_TRAP_REGISTERS *SmodeTrapReg
+ )
+{
+ UINTN SCause;
+ EFI_SYSTEM_CONTEXT RiscVSystemContext;
+
+ RiscVSystemContext.SystemContextRiscV64 =
(EFI_SYSTEM_CONTEXT_RISCV64 *)SmodeTrapReg;
+ //
+ // Check scasue register.
+ //
+ SCause = (UINTN)RiscVGetSupervisorTrapCause ();
+ if ((SCause & (1UL << (sizeof (UINTN) * 8- 1))) != 0) {
+ //
+ // This is interrupt event.
+ //
+ SCause &= ~(1UL << (sizeof (UINTN) * 8- 1));
+ if ((SCause == IRQ_S_TIMER) &&
(mInterruptHandlers[EXCEPT_RISCV_TIMER_INT] != NULL)) {
+
mInterruptHandlers[EXCEPT_RISCV_TIMER_INT](EXCEPT_RISCV_TIMER_INT,
RiscVSystemContext);
+ }
+ }
+}
diff --git
a/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/SupervisorTrapHand
ler.S
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/SupervisorTrapHand
ler.S
new file mode 100644
index 000000000000..649c4c5becf4
--- /dev/null
+++
b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/SupervisorTrapHand
ler.S
@@ -0,0 +1,105 @@
+/** @file
+ RISC-V Processor supervisor mode trap handler
+
+ Copyright (c) 2019, Hewlett Packard Enterprise Development LP. All rights
reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Base.h>
+#include "CpuExceptionHandlerLib.h"
+
+ .align 3
+ .section .entry, "ax", %progbits
+ .globl SupervisorModeTrap
+SupervisorModeTrap:
+ addi sp, sp, -SMODE_TRAP_REGS_SIZE
+
+ /* Save all general regisers except SP */
+ sd t0, SMODE_TRAP_REGS_OFFSET(t0)(sp)
+
+ csrr t0, CSR_SSTATUS
+ and t0, t0, (SSTATUS_SIE | SSTATUS_SPIE)
+ sd t0, SMODE_TRAP_REGS_OFFSET(sstatus)(sp)
+ csrr t0, CSR_SEPC
+ sd t0, SMODE_TRAP_REGS_OFFSET(sepc)(sp)
+ csrr t0, CSR_SIE
+ sd t0, SMODE_TRAP_REGS_OFFSET(sie)(sp)
+ ld t0, SMODE_TRAP_REGS_OFFSET(t0)(sp)
+
+ sd ra, SMODE_TRAP_REGS_OFFSET(ra)(sp)
+ sd gp, SMODE_TRAP_REGS_OFFSET(gp)(sp)
+ sd tp, SMODE_TRAP_REGS_OFFSET(tp)(sp)
+ sd t1, SMODE_TRAP_REGS_OFFSET(t1)(sp)
+ sd t2, SMODE_TRAP_REGS_OFFSET(t2)(sp)
+ sd s0, SMODE_TRAP_REGS_OFFSET(s0)(sp)
+ sd s1, SMODE_TRAP_REGS_OFFSET(s1)(sp)
+ sd a0, SMODE_TRAP_REGS_OFFSET(a0)(sp)
+ sd a1, SMODE_TRAP_REGS_OFFSET(a1)(sp)
+ sd a2, SMODE_TRAP_REGS_OFFSET(a2)(sp)
+ sd a3, SMODE_TRAP_REGS_OFFSET(a3)(sp)
+ sd a4, SMODE_TRAP_REGS_OFFSET(a4)(sp)
+ sd a5, SMODE_TRAP_REGS_OFFSET(a5)(sp)
+ sd a6, SMODE_TRAP_REGS_OFFSET(a6)(sp)
+ sd a7, SMODE_TRAP_REGS_OFFSET(a7)(sp)
+ sd s2, SMODE_TRAP_REGS_OFFSET(s2)(sp)
+ sd s3, SMODE_TRAP_REGS_OFFSET(s3)(sp)
+ sd s4, SMODE_TRAP_REGS_OFFSET(s4)(sp)
+ sd s5, SMODE_TRAP_REGS_OFFSET(s5)(sp)
+ sd s6, SMODE_TRAP_REGS_OFFSET(s6)(sp)
+ sd s7, SMODE_TRAP_REGS_OFFSET(s7)(sp)
+ sd s8, SMODE_TRAP_REGS_OFFSET(s8)(sp)
+ sd s9, SMODE_TRAP_REGS_OFFSET(s9)(sp)
+ sd s10, SMODE_TRAP_REGS_OFFSET(s10)(sp)
+ sd s11, SMODE_TRAP_REGS_OFFSET(s11)(sp)
+ sd t3, SMODE_TRAP_REGS_OFFSET(t3)(sp)
+ sd t4, SMODE_TRAP_REGS_OFFSET(t4)(sp)
+ sd t5, SMODE_TRAP_REGS_OFFSET(t5)(sp)
+ sd t6, SMODE_TRAP_REGS_OFFSET(t6)(sp)
+
+ /* Call to Supervisor mode trap handler in CpuExceptionHandlerLib.c */
+ call RiscVSupervisorModeTrapHandler
+
+ /* Restore all general regisers except SP */
+ ld ra, SMODE_TRAP_REGS_OFFSET(ra)(sp)
+ ld gp, SMODE_TRAP_REGS_OFFSET(gp)(sp)
+ ld tp, SMODE_TRAP_REGS_OFFSET(tp)(sp)
+ ld t2, SMODE_TRAP_REGS_OFFSET(t2)(sp)
+ ld s0, SMODE_TRAP_REGS_OFFSET(s0)(sp)
+ ld s1, SMODE_TRAP_REGS_OFFSET(s1)(sp)
+ ld a0, SMODE_TRAP_REGS_OFFSET(a0)(sp)
+ ld a1, SMODE_TRAP_REGS_OFFSET(a1)(sp)
+ ld a2, SMODE_TRAP_REGS_OFFSET(a2)(sp)
+ ld a3, SMODE_TRAP_REGS_OFFSET(a3)(sp)
+ ld a4, SMODE_TRAP_REGS_OFFSET(a4)(sp)
+ ld a5, SMODE_TRAP_REGS_OFFSET(a5)(sp)
+ ld a6, SMODE_TRAP_REGS_OFFSET(a6)(sp)
+ ld a7, SMODE_TRAP_REGS_OFFSET(a7)(sp)
+ ld s2, SMODE_TRAP_REGS_OFFSET(s2)(sp)
+ ld s3, SMODE_TRAP_REGS_OFFSET(s3)(sp)
+ ld s4, SMODE_TRAP_REGS_OFFSET(s4)(sp)
+ ld s5, SMODE_TRAP_REGS_OFFSET(s5)(sp)
+ ld s6, SMODE_TRAP_REGS_OFFSET(s6)(sp)
+ ld s7, SMODE_TRAP_REGS_OFFSET(s7)(sp)
+ ld s8, SMODE_TRAP_REGS_OFFSET(s8)(sp)
+ ld s9, SMODE_TRAP_REGS_OFFSET(s9)(sp)
+ ld s10, SMODE_TRAP_REGS_OFFSET(s10)(sp)
+ ld s11, SMODE_TRAP_REGS_OFFSET(s11)(sp)
+ ld t3, SMODE_TRAP_REGS_OFFSET(t3)(sp)
+ ld t4, SMODE_TRAP_REGS_OFFSET(t4)(sp)
+ ld t5, SMODE_TRAP_REGS_OFFSET(t5)(sp)
+ ld t6, SMODE_TRAP_REGS_OFFSET(t6)(sp)
+
+ ld t0, SMODE_TRAP_REGS_OFFSET(sepc)(sp)
+ csrw CSR_SEPC, t0
+ ld t0, SMODE_TRAP_REGS_OFFSET(sie)(sp)
+ csrw CSR_SIE, t0
+ csrr t0, CSR_SSTATUS
+ ld t1, SMODE_TRAP_REGS_OFFSET(sstatus)(sp)
+ or t0, t0, t1
+ csrw CSR_SSTATUS, t0
+ ld t1, SMODE_TRAP_REGS_OFFSET(t1)(sp)
+ ld t0, SMODE_TRAP_REGS_OFFSET(t0)(sp)
+ addi sp, sp, SMODE_TRAP_REGS_SIZE
+ sret
--
2.38.0