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Thu, 13 Oct 2022 02:59:22 -0700 (PDT) From: "Sunil V L" To: devel@edk2.groups.io Cc: Eric Dong , Ray Ni , Rahul Kumar , Daniel Schaefer Subject: [edk2-staging/RiscV64QemuVirt PATCH V3 16/34] UefiCpuPkg/CpuExceptionHandlerLib: Add support for RISC-V Date: Thu, 13 Oct 2022 15:28:11 +0530 Message-Id: <20221013095829.1454581-17-sunilvl@ventanamicro.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221013095829.1454581-1-sunilvl@ventanamicro.com> References: <20221013095829.1454581-1-sunilvl@ventanamicro.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4076 Cc: Eric Dong Cc: Ray Ni Cc: Rahul Kumar Cc: Daniel Schaefer Signed-off-by: Sunil V L --- .../DxeCpuExceptionHandlerLib.inf | 7 +- .../SecPeiCpuExceptionHandlerLib.inf | 7 +- .../RiscV64/CpuExceptionHandlerLib.h | 116 +++++++++++++++ .../RiscV64/CpuExceptionHandlerLib.c | 133 ++++++++++++++++++ .../RiscV64/SupervisorTrapHandler.S | 105 ++++++++++++++ 5 files changed, 366 insertions(+), 2 deletions(-) create mode 100644 UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerLib.h create mode 100644 UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerLib.c create mode 100644 UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/SupervisorTrapHandler.S diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/DxeCpuExceptionHandlerLib.inf b/UefiCpuPkg/Library/CpuExceptionHandlerLib/DxeCpuExceptionHandlerLib.inf index ef07b05c080a..b689e7af56e7 100644 --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/DxeCpuExceptionHandlerLib.inf +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/DxeCpuExceptionHandlerLib.inf @@ -18,7 +18,7 @@ [Defines] # # The following information is for reference only and not required by the build tools. # -# VALID_ARCHITECTURES = IA32 X64 +# VALID_ARCHITECTURES = IA32 X64 RISCV64 # [Sources.Ia32] @@ -38,6 +38,11 @@ [Sources.IA32, Sources.X64] Ia32_X64/PeiDxeSmmCpuException.c Ia32_X64/DxeException.c +[Sources.RISCV64] + RiscV64/SupervisorTrapHandler.S + RiscV64/CpuExceptionHandlerLib.c + RiscV64/CpuExceptionHandlerLib.h + [Pcd] gEfiMdeModulePkgTokenSpaceGuid.PcdCpuStackGuard gUefiCpuPkgTokenSpaceGuid.PcdCpuStackSwitchExceptionList diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuExceptionHandlerLib.inf b/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuExceptionHandlerLib.inf index 28341abd4493..b490ef5aff8a 100644 --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuExceptionHandlerLib.inf +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuExceptionHandlerLib.inf @@ -18,7 +18,7 @@ [Defines] # # The following information is for reference only and not required by the build tools. # -# VALID_ARCHITECTURES = IA32 X64 +# VALID_ARCHITECTURES = IA32 X64 RISCV64 # [Sources.Ia32] @@ -37,6 +37,11 @@ [Sources.IA32, Sources.X64] Ia32_X64/CpuExceptionCommon.c Ia32_X64/SecPeiCpuException.c +[Sources.RISCV64] + RiscV64/SupervisorTrapHandler.S + RiscV64/CpuExceptionHandlerLib.c + RiscV64/CpuExceptionHandlerLib.h + [Packages] MdePkg/MdePkg.dec MdeModulePkg/MdeModulePkg.dec diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerLib.h b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerLib.h new file mode 100644 index 000000000000..30f47e87552b --- /dev/null +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerLib.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.
+ + SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#ifndef RISCV_CPU_EXECPTION_HANDLER_LIB_H_ +#define RISCV_CPU_EXECPTION_HANDLER_LIB_H_ + +#include + +/** + 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/CpuExceptionHandlerLib.c b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerLib.c new file mode 100644 index 000000000000..f1ee7d236aec --- /dev/null +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/CpuExceptionHandlerLib.c @@ -0,0 +1,133 @@ +/** @file + RISC-V Exception Handler library implementation. + + Copyright (c) 2016 - 2022, Hewlett Packard Enterprise Development LP. All rights reserved.
+ + SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#include +#include +#include +#include +#include + +#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/SupervisorTrapHandler.S b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/SupervisorTrapHandler.S new file mode 100644 index 000000000000..649c4c5becf4 --- /dev/null +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/RiscV64/SupervisorTrapHandler.S @@ -0,0 +1,105 @@ +/** @file + RISC-V Processor supervisor mode trap handler + + Copyright (c) 2019, Hewlett Packard Enterprise Development LP. All rights reserved.
+ + SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#include +#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 -- 2.25.1