when amisaligned load or store(4、6)causes an access-fault or page-fault exception, then stval will contain the virtual address of the portion of the access that caused the fault. when aninstruction access-fault
对于R=0 且 W=1的情况不符合实际含义,故作为保留,以便未来某些情况下使用。 当一条指令试图execute, load, store但遭到拒绝时,分别触发instruction access-fault exception, load access-fault exception, store access-fault exception。 Address Matching 之前说明了,一个PMP entry由一个地址寄存器和一个配置寄存器组...
01Instruction access fault 02Illegal instruction 03Breakpoint 04Load address misaligned 05Load access ...
01Instruction access fault 02Illegal Instruction 03Breakpoint 04Load address misaligned 05Load access ...
01Instructionaccess fault 02Illegal instruction 03Breakpoint 04Load address misaligned 05Load access fault 06Store/AMO address misaligned 07Store/AMO access fault 08Environment call from U-mode 09Environment call from S-mode 010–11Reserved 012Instruction page fault ...
1 指令访问错误(Instruction access fault) 同步 取指令访存错误。 mdcause提供详细的指令放错误类型: 2 非法指令(Illegal instruction) 同步 非法指令。 3 断点(Breakpoint) 同步 RISC-V架构定义了EBREAK指令,当处理器执行到该指令时,会发生异常进入异常服务程序。该指令往往用于调试器(Debugger)使用,譬如设置断点 ...
配置寄存器包含权限位，如R、W、X，分别表示读、写、执行权限，为1表示有权限，为0表示无权限。R=0且W=1的情况是预留的，以供未来使用。当指令尝试执行、加载或存储时遭到拒绝，会触发相应的异常：instruction access-fault exception、load access-fault exception、store access-fault exception。一个...
Failed read or write accesses generate a load or store access exception, and an instruction access fault would occur on a failed instruction fetch. When an exception occurs while attempting to execute from a region without execute permissions, the fault occurs on the fetch and not the branch, ...
Access fault for non-existent regions Performance monitors Program code performance tuning StackSafe™ hardware stack protection Easy identification of stack size threshold during development Hardware error detection of stack overflow and underflow at runtime Multiplier options Fast multiplier: pipelined, 2...
Access fault for non-existent regions Performance monitors Program code performance tuning Multiplier options Fast multiplier: pipelined, 2-cycle Small multipliers: producing 1, 2, 4, or 8 bits per cycle Option to choose between speed and area according to application's requirements PowerBrake technol...