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Remove mstatus.CRG (#443)
The CRG bit is associated with the matching translation table base register. As there is no matp (only satp), remove the mstatus.CRG bit. Fixes: #441
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src/cheri-pte-ext.adoc

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@@ -10,6 +10,8 @@ capabilities in memory at the page granularity. For this reason, the
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{cheri_pte_ext_name} extension adds new bits to RISC-V's Page Table Entry (PTE)
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format.
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{cheri_pte_ext_name} requires at least one virtual memory translation scheme (_Sv39_, _Sv48_ or _Sv57_) to be implemented.
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=== Limiting Capability Propagation
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Page table enforcement can allow the operating system to limit the flow
@@ -155,55 +157,11 @@ bit value of the capability read. This will introduce additional traps during re
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a hardware updating mechanism.
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[#xstatus_pte]
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=== Extending the Machine (mstatus), Supervisor (sstatus) and Virtual Supervisor (vsstatus) Status Registers
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The <<mstatusreg_pte,mstatus>>, <<sstatusreg_pte,status>> and <<vsstatusreg_pte,vsstatus>> CSRs are extended to include the new Capability Read Generation (CRG) bit as shown.
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=== Extending the Supervisor (sstatus) and Virtual Supervisor (vsstatus) Status Registers
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mstatus.CRG is made visible in sstatus.CRG.
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The <<sstatusreg_pte,sstatus>> and <<vsstatusreg_pte,vsstatus>> CSRs are extended to include the new Capability Read Generation (CRG) bit as shown.
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When V=1 vsstatus.CRG is in effect.
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[#mstatusreg_pte]
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.Machine-mode status (*mstatus*) register when MXLEN=64
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[wavedrom, ,svg]
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....
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{reg: [
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{bits: 1, name: 'WPRI'},
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{bits: 1, name: 'SIE'},
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{bits: 1, name: 'WPRI'},
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{bits: 1, name: 'MIE'},
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{bits: 1, name: 'WPRI'},
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{bits: 1, name: 'SPIE'},
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{bits: 1, name: 'UBE'},
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{bits: 1, name: 'MPIE'},
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{bits: 1, name: 'SPP'},
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{bits: 2, name: 'VS[1:0]'},
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{bits: 2, name: 'MPP[1:0]'},
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{bits: 2, name: 'FS[1:0]'},
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{bits: 2, name: 'XS[1:0]'},
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{bits: 1, name: 'MPRV'},
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{bits: 1, name: 'SUM'},
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{bits: 1, name: 'MXR'},
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{bits: 1, name: 'TVM'},
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{bits: 1, name: 'TW'},
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{bits: 1, name: 'TSR'},
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{bits: 1, name: 'SPELP'},
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{bits: 1, name: 'SDT'},
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{bits: 7, name: 'WPRI'},
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{bits: 2, name: 'UXL[1:0]'},
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{bits: 2, name: 'SXL[1:0]'},
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{bits: 1, name: 'SBE'},
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{bits: 1, name: 'MBE'},
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{bits: 1, name: 'GVA'},
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{bits: 1, name: 'MPV'},
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{bits: 1, name: 'WPRI'},
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{bits: 1, name: 'MPELP'},
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{bits: 1, name: 'MDT'},
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{bits: 19, name: 'WPRI'},
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{bits: 1, name: 'CRG'},
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{bits: 1, name: 'SD'},
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], config:{lanes: 4, hspace:1024}}
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....
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When V=1 <<vsstatusreg_pte,vsstatus>>.CRG is in effect.
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[#sstatusreg_pte]
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.Supervisor-mode status (*sstatus*) register when SXLEN=64

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