| 76,8 → 76,6 |
|---|
| * Handler of the Fast Data Access MMU Miss trap. If the trap occurred in the kernel |
| * (context 0), an identity mapping (with displacement) is installed. Otherwise |
| * a higher level service routine is called. |
| * |
| * TODO implement calling the higher level service routine |
| */ |
| .macro FAST_DATA_ACCESS_MMU_MISS_HANDLER tl |
| |
| 84,11 → 82,9 |
|---|
| mov SCRATCHPAD_MMU_FSA, %g1 |
| ldxa [%g1] ASI_SCRATCHPAD, %g1 ! g1 <= RA of MMU fault status area |
| |
| /* service by higher-level routine when context != 0 */ |
| /* read faulting context */ |
| add %g1, FSA_DFC_OFFSET, %g2 ! g2 <= RA of data fault context |
| ldxa [%g2] ASI_REAL, %g3 ! read the fault context |
| brnz %g3, 0f |
| nop |
| |
| /* read the faulting address */ |
| add %g1, FSA_DFA_OFFSET, %g2 ! g2 <= RA of data fault address |
| 96,19 → 92,80 |
|---|
| srlx %g1, TTE_DATA_TADDR_OFFSET, %g1 ! truncate it to page boundary |
| sllx %g1, TTE_DATA_TADDR_OFFSET, %g1 |
| |
| /* service by higher-level routine when context != 0 */ |
| brnz %g3, 0f |
| nop |
| |
| /* exclude page number 0 from installing the identity mapping */ |
| brz %g1, 0f |
| nop |
| |
| /* installing the identity does not fit into 32 instructions, call a separate routine */ |
| /* |
| * Installing the identity does not fit into 32 instructions, call |
| * a separate routine. The routine performs RETRY, hence the call never |
| * returns. |
| */ |
| ba install_identity_mapping |
| nop |
| |
| 0: ! TODO - call higher level service routine |
| 0: |
| |
| /* |
| * One of the scenarios in which this trap can occur is when the |
| * register window spill/fill handler accesses a memory which is not |
| * mapped. In such a case, this handler will be called from TL = 1. |
| * We handle the situation by pretending that the MMU miss occurred |
| * on TL = 0. Once the MMU miss trap is services, the instruction which |
| * caused the spill/fill trap is restarted, the spill/fill trap occurs, |
| * but this time its handler accesse memory which IS mapped. |
| */ |
| .if (\tl > 0) |
| wrpr %g0, 1, %tl |
| .endif |
| |
| /* |
| * Save the faulting virtual page and faulting context to the %g2 |
| * register. The most significant 51 bits of the %g2 register will |
| * contain the virtual address which caused the fault truncated to the |
| * page boundary. The least significant 13 bits of the %g2 register |
| * will contain the number of the context in which the fault occurred. |
| * The value of the %g2 register will be passed as a parameter to the |
| * higher level service routine. |
| */ |
| or %g1, %g3, %g2 |
| |
| PREEMPTIBLE_HANDLER fast_data_access_mmu_miss |
| .endm |
| |
| /* |
| * Handler of the Fast Data MMU Protection trap. Finds the trapping address |
| * and context and calls higher level service routine. |
| */ |
| .macro FAST_DATA_ACCESS_PROTECTION_HANDLER tl |
| /* |
| * The same special case as in FAST_DATA_ACCESS_MMU_MISS_HANDLER. |
| */ |
| .if (\tl > 0) |
| wrpr %g0, 1, %tl |
| .endif |
| |
| mov SCRATCHPAD_MMU_FSA, %g1 |
| ldxa [%g1] ASI_SCRATCHPAD, %g1 ! g1 <= RA of MMU fault status area |
| |
| /* read faulting context */ |
| add %g1, FSA_DFC_OFFSET, %g2 ! g2 <= RA of data fault context |
| ldxa [%g2] ASI_REAL, %g3 ! read the fault context |
| |
| /* read the faulting address */ |
| add %g1, FSA_DFA_OFFSET, %g2 ! g2 <= RA of data fault address |
| ldxa [%g2] ASI_REAL, %g1 ! read the fault address |
| srlx %g1, TTE_DATA_TADDR_OFFSET, %g1 ! truncate it to page boundary |
| sllx %g1, TTE_DATA_TADDR_OFFSET, %g1 |
| |
| /* the same as for FAST_DATA_ACCESS_MMU_MISS_HANDLER */ |
| or %g1, %g3, %g2 |
| |
| PREEMPTIBLE_HANDLER fast_data_access_protection |
| .endm |
| |
| #endif /* __ASM__ */ |