Implement the SBI IPI (Inter-Processor Interrupt) extension to enable
guest VMs to send software interrupts between virtual CPUs.
The implementation handles the SBI_IPI_SEND_IPI function call, which
allows a guest to target one or more vCPUs using either:
- A mask (bitmap of target harts relative to a base hart ID)
- Broadcast mode (when mask_base is UINT64_MAX)
The IPI is delivered by asserting the VS-level software interrupt
(VSSIP, bit 2) on each target vCPU. Proper validation is performed
to ensure hart IDs are within valid range and all masked harts exist.
Tracked-On: #8851
Signed-off-by: Haoyu Tang <haoyu.tang@intel.com>
Acked-by: Wang Yu1 <yu1.wang@intel.com>
Implement the SBI TIME (Timer) extension to allow guest VMs to program
virtual timer interrupts through the SBI interface.
The implementation handles the SBI_TIME_SET_TIMER function call, which
allows guests to set the vstimecmp CSR to schedule timer interrupts.
The vstimecmp value is written directly to the CSR and saved in the
vCPU context.
Tracked-On: #8851
Signed-off-by: Haoyu Tang <haoyu.tang@intel.com>
Acked-by: Wang Yu1 <yu1.wang@intel.com>
Add virtual exception handling infrastructure for RISC-V hypervisor
and enables proper virtualization of RISC-V exceptions by allowing
the hypervisor to inject exceptions into guest VS-mode.
- Implement vcpu_set_trap() to inject traps to VS-mode
- Implement vcpu_queue_exception() to queue exceptions for vCPU injection
- Process pending exception requests in riscv_process_vcpu_requests()
v1->v2:
change vcpu_redirect_trap -> vcpu_set_trap
Tracked-On: #8844
Signed-off-by: Yi Y Sun <yi.y.sun@intel.com>
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Wang Yu1 <yu1.wang@intel.com>
Currently dbcn outputs directly to console. Outputs to ACRN
shell vm_console when other dependencies are ready.
Tracked-On: #8841
Signed-off-by: Yifan Liu <yifan1.liu@intel.com>
Acked-by: Wang Yu1 <yu1.wang@intel.com>
Unlike x86 which explicitly distinguishes guest traps and host traps (VM
exits vs. IDT trap gates), risc-v unifies them to a single trap gate
with bits in multiple CSRs representing the privilege mode before the
trap. This commit follows this design.
Due to this change the arch_vcpu_thread in risc-v was basically
abandoned, and used only as a first-time entry point to guest, with the
rest of the original x86 arch_vcpu_thread being re-implemented following
above single-entry design.
Save/restore routine is also being re-implemented to account for
both hs-mode traps and v-mode traps. sscratch is used to mark the place
where the context is being saved to/restored from. When sscratch is
zero at the time of the trap, the context is saved into host stack.
When sscratch is non-zero, the context is saved to vcpu->arch.regs
(similar for restore).
Tracked-On: #8841
Signed-off-by: Yifan Liu <yifan1.liu@intel.com>
Signed-off-by: Haicheng Li <haicheng.li@intel.com>
Acked-by: Wang Yu1 <yu1.wang@intel.com>
Besides implementing copy_from/to_gpa, this commit also wraps a dummy
commit in mmu.c that exposes API of adding hv mmu mapping.
Tracked-On: #8830
Signed-off-by: Yifan Liu <yifan1.liu@intel.com>
Reviewed-by: Fei Li <fei1.li@intel.com>
Acked-by: Wang Yu1 <yu1.wang@intel.com>
Add stack protector implementation for RISC-V architecture using a
global __stack_chk_guard variable. This differs from x86 which uses
per-CPU stack canaries.
Tracked-On: #8834
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Reviewed-by: Fei Li <fei1.li@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
Add RISC-V specific implementation of arch_get_random_value() that
combines entropy from rdcycle and rdtime counters. This provides a
portable solution since the Zkr entropy extension is optional in RVA23
profile.
Tracked-On: #8834
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Reviewed-by: Fei Li <fei1.li@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
The following flags are assigned to CFLAGS/LDFLAGS when trying to build
a relocatable acrn.out (ELF):
- CFLAGS += -fpie & ASFLAGS += -fpie:
- Produces position-independent code suitable for executables (not shared libraries).
- Uses PC-relative addressing for global variables and function calls
- Generates code that can be loaded at any memory address
- Together with -mcmodel=medany is used to support "Medium Position
Independent Code Model"
- CFLAGS += -fvisibility=hidden:
- Enabled with --gc-sections, the -fvisibility=hidden compiler flag
increases the number of symbols the linker can identify and remove
as unused. This reduces the final binary size and can improve
performance
- LDFLAGS += -shared:
- Create a shared object (ELF::e_type == 3) instead of an executable
- This is required to support a relocatable acrn.out
- LDFLAGS += -Wl,-z,notext
- Allow relocations in read-only segments (text relocations)
- Resolves linking errors when absolute addresses exist in read-only
sections
- LDFLAGS += -Wl,-Bsymbolic
- Prioritizes local symbol definitions over external ones
- Improves performance by avoiding PLT (Procedure Linkage Table) calls
for local symbols
- LDFLAGS += -Wl,-z,defs
- Forces the linker to resolve all symbol references at link time
- Report undefined symbol errors during linking
In summary:
- -fpie + -shared: Creates a position-independent shared object that can
be loaded as an executables
- -z,notext + -Bsymbolic: Allows internal relocations while keeping
symbols local
- -z,defs: Ensures all symbols are properly defined, preventing runtime
errors
We are using --start-group/--end-group to link all the modules. When
using -shared, the linker discards unused symbols by default, even if
they are marked with KEEP() in the linker script. This is because shared
libraries typically allow undefined symbols to be resolved at runtime.
To ensure the entry point is included, we need to add EXTERN(_start) to
the linker script, which forces the linker to treat _start as a required
symbol that must be resolved during the linking process.
Tracked-On: #8825
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
This patch implements relocation support for ACRN RISC-V to enable
position-independent execution. The hypervisor can now be loaded at any
physical address and will automatically relocate itself at runtime. Key
changes:
- Add relocate() function to process R_RISCV_RELATIVE relocations in
.rela sections during early boot
- Implement arch_get_hv_image_delta() to calculate the load address offset
from the configured base address
- Add relocation processing in cpu_entry.S before jumping to C code
- Update linker script to include .rela sections for relocation data
- Define R_RISCV_RELATIVE relocation type and linker symbol definitions
Tracked-On: #8825
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
Add hypervisor pagetable manipulate interface to riscv arch directory,
which is needed by the common interface, and add riscv ppt pgtable
structure implementation.
Tracked-On: #8831
Signed-off-by: Haicheng Li <haicheng.li@intel.com>
Co-developed-by: hangliu1 <hang1.liu@intel.com>
Signed-off-by: hangliu1 <hang1.liu@intel.com>
Reviewed-by: Fei Li <fei1.li@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
For now, BOARD should use the qemu-riscv for risc-v.
For RISC-V:
make hypervisor BOARD=qemu-riscv SCENARIO=shared ARCH=riscv CROSS_COMPILE=riscv64-linux-gnu-
For x86:
make hypervisor BOARD=qemu SCENARIO=shared [ARCH=x86]
Tracked-On: #8805
Signed-off-by: Fei Li <fei1.li@intel.com>
This patch implements interrupt initialization and the basic
exception/interrupt handling flow on RISC-V.
init_interrupt() needs to be invoked during CPU initialization to
set up the trap vector and enable the interrupt.
RISC-V exception and interrupt handling includes:
- Saving and restoring CPU registers around traps
- Implementing handlers for:
- Supervisor software interrupt
- Supervisor timer interrupt
- Halting the CPU for all other interrupts and exceptions
------
TODOs:
1. add support for registering interrupt handlers via request_irq() and
further adoption of the common IRQ framework.
2. add support for external interrupt.
Tracked-On: #8813
Signed-off-by: Haicheng Li <haicheng.li@intel.com>
Co-developed-by: Shiqing Gao <shiqing.gao@intel.com>
Signed-off-by: Shiqing Gao <shiqing.gao@intel.com>
Reviewed-by: Yifan Liu <yifan1.liu@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
Without -fpie or -fno-pie specified in the CFLAGS and ASFLAGS, different
versions of riscv64-linux-gnu-gcc have different behavior, for example,
Ubuntu 13.3.0-6ubuntu2~24.04 will compile as if -fpie, but 15.1.0 will
compile as if -fno-pie. To make the build consistent specify -fpie when
CONFIG_RELOC=y and -fno-pie otherwize explicitly.
Tracked-On: #8791
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
Extension Zihintpause (Pause hint) is mandatory for RVA23. asm_pause
is implemented based on "pause" instruction.
Tracked-On: #8791
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
This is just for temporary build and should be reverted when
common debug module is integrated.
Tracked-On: #8791
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
This patch implements risc-v specific timer codes. Basically,
risc-v adapts to acrn timer framework with some specific
behaviors. So far, it enables sstc support in h-mode.
Tracked-On: #8792
Signed-off-by: Haicheng Li <haicheng.li@outlook.com>
Co-developed-by: Yong Li <yong.li@intel.com>
Signed-off-by: Yong Li <yong.li@intel.com>
Co-developed-by: Yi Y Sun <yi.y.sun@intel.com>
Signed-off-by: Yi Y Sun <yi.y.sun@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
This patch implements the IPI for RISC-V using SBI interface.
There is no common IPI concept abstracted, due to the following reasons:
- RISC-V:
Software delivers an IPI to target CPUs via software interrupts.
The interrupt number is fixed for each privilege mode (e.g.,
Supervisor Software Interrupt = IRQ 1, Machine Software Interrupt = IRQ 3).
The actual purpose of the IPI is indicated by an IPI message type,
which is a software-level concept. When the IPI is received,
the target CPU must check the message type to determine the required action.
- x86:
Software delivers an IPI to target CPUs using a specific vector number.
During CPU initialization, software can assign dedicated vectors for
particular purposes. When the IPI is received, the target CPU could
directly invoke the handler bound to that vector.
Each architecture provides its own IPI implementation, and other SW modules
directly call these arch-specific functions.
------
Notes:
* To ensure RISC-V builds pass, an empty `include/arch/riscv/asm/cpu.h`
is added since `debug/logmsg.h` includes `asm/cpu.h`.
* Implemented IPI functionality using the SBI IPI Extension (EID #0x735049).
Legacy SBI extensions are not supported in ACRN.
----------
Changelog:
* Updated commit message and code comments to state explicitly that
legacy SBI extensions are not supported in ACRN.
* Refined the prototype of sbi_send_ipi() to align with the SBI spec:
From: int64_t sbi_send_ipi(uint64_t mask)
To: int64_t sbi_send_ipi(uint64_t mask, uint64_t mask_base)
In ACRN it is invoked as sbi_send_ipi(dest_mask, 0UL), with mask_base
set to 0UL.
* Renamed send_single_ipi() and send_dest_ipi_mask() to
arch_send_single_ipi() and arch_send_dest_ipi_mask() respectively.
Tracked-On: #8786
Signed-off-by: Haicheng Li <haicheng.li@intel.com>
Co-developed-by: Shiqing Gao <shiqing.gao@intel.com>
Signed-off-by: Shiqing Gao <shiqing.gao@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
This commit adds riscv build skeleton and adds some dummy files that
prints out hello world.
To build riscv acrn.out/acrn.bin, simply:
make hypervisor \
BOARD=<any existing board> \
SCENARIO=<any existing scenario> \
ARCH=riscv
We still need to specify board and scenario as those were required by
project level makefile.
Tracked-On: #8782
Signed-off-by: Yifan Liu <yifan1.liu@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>
