diff options
-rw-r--r-- | arch/ia64/kernel/mca_asm.S | 96 | ||||
-rw-r--r-- | include/asm-ia64/mca.h | 5 |
2 files changed, 90 insertions, 11 deletions
diff --git a/arch/ia64/kernel/mca_asm.S b/arch/ia64/kernel/mca_asm.S index 499a065..db32fc1 100644 --- a/arch/ia64/kernel/mca_asm.S +++ b/arch/ia64/kernel/mca_asm.S @@ -489,24 +489,27 @@ ia64_state_save: ;; st8 [temp1]=r17,16 // pal_min_state st8 [temp2]=r6,16 // prev_IA64_KR_CURRENT + mov r6=IA64_KR(CURRENT_STACK) + ;; + st8 [temp1]=r6,16 // prev_IA64_KR_CURRENT_STACK + st8 [temp2]=r0,16 // prev_task, starts off as NULL mov r6=cr.ifa ;; - st8 [temp1]=r0,16 // prev_task, starts off as NULL - st8 [temp2]=r12,16 // cr.isr + st8 [temp1]=r12,16 // cr.isr + st8 [temp2]=r6,16 // cr.ifa mov r12=cr.itir ;; - st8 [temp1]=r6,16 // cr.ifa - st8 [temp2]=r12,16 // cr.itir + st8 [temp1]=r12,16 // cr.itir + st8 [temp2]=r11,16 // cr.iipa mov r12=cr.iim ;; - st8 [temp1]=r11,16 // cr.iipa - st8 [temp2]=r12,16 // cr.iim - mov r6=cr.iha + st8 [temp1]=r12,16 // cr.iim (p1) mov r12=IA64_MCA_COLD_BOOT (p2) mov r12=IA64_INIT_WARM_BOOT + mov r6=cr.iha ;; - st8 [temp1]=r6,16 // cr.iha - st8 [temp2]=r12 // os_status, default is cold boot + st8 [temp2]=r6,16 // cr.iha + st8 [temp1]=r12 // os_status, default is cold boot mov r6=IA64_MCA_SAME_CONTEXT ;; st8 [temp1]=r6 // context, default is same context @@ -823,9 +826,12 @@ ia64_state_restore: ld8 r12=[temp1],16 // sal_ra ld8 r9=[temp2],16 // sal_gp ;; - ld8 r22=[temp1],24 // pal_min_state, virtual. skip prev_task + ld8 r22=[temp1],16 // pal_min_state, virtual ld8 r21=[temp2],16 // prev_IA64_KR_CURRENT ;; + ld8 r16=[temp1],16 // prev_IA64_KR_CURRENT_STACK + ld8 r20=[temp2],16 // prev_task + ;; ld8 temp3=[temp1],16 // cr.isr ld8 temp4=[temp2],16 // cr.ifa ;; @@ -846,6 +852,45 @@ ia64_state_restore: ld8 r8=[temp1] // os_status ld8 r10=[temp2] // context + /* Wire IA64_TR_CURRENT_STACK to the stack that we are resuming to. To + * avoid any dependencies on the algorithm in ia64_switch_to(), just + * purge any existing CURRENT_STACK mapping and insert the new one. + * + * r16 contains prev_IA64_KR_CURRENT_STACK, r21 contains + * prev_IA64_KR_CURRENT, these values may have been changed by the C + * code. Do not use r8, r9, r10, r22, they contain values ready for + * the return to SAL. + */ + + mov r15=IA64_KR(CURRENT_STACK) // physical granule mapped by IA64_TR_CURRENT_STACK + ;; + shl r15=r15,IA64_GRANULE_SHIFT + ;; + dep r15=-1,r15,61,3 // virtual granule + mov r18=IA64_GRANULE_SHIFT<<2 // for cr.itir.ps + ;; + ptr.d r15,r18 + ;; + srlz.d + + extr.u r19=r21,61,3 // r21 = prev_IA64_KR_CURRENT + shl r20=r16,IA64_GRANULE_SHIFT // r16 = prev_IA64_KR_CURRENT_STACK + movl r21=PAGE_KERNEL // page properties + ;; + mov IA64_KR(CURRENT_STACK)=r16 + cmp.ne p6,p0=RGN_KERNEL,r19 // new stack is in the kernel region? + or r21=r20,r21 // construct PA | page properties +(p6) br.spnt 1f // the dreaded cpu 0 idle task in region 5:( + ;; + mov cr.itir=r18 + mov cr.ifa=r21 + mov r20=IA64_TR_CURRENT_STACK + ;; + itr.d dtr[r20]=r21 + ;; + srlz.d +1: + br.sptk b0 //EndStub////////////////////////////////////////////////////////////////////// @@ -982,6 +1027,7 @@ ia64_set_kernel_registers: add temp4=temp4, temp1 // &struct ia64_sal_os_state.os_gp add r12=temp1, temp3 // kernel stack pointer on MCA/INIT stack add r13=temp1, r3 // set current to start of MCA/INIT stack + add r20=temp1, r3 // physical start of MCA/INIT stack ;; ld8 r1=[temp4] // OS GP from SAL OS state ;; @@ -991,7 +1037,35 @@ ia64_set_kernel_registers: ;; mov IA64_KR(CURRENT)=r13 - // FIXME: do I need to wire IA64_KR_CURRENT_STACK and IA64_TR_CURRENT_STACK? + /* Wire IA64_TR_CURRENT_STACK to the MCA/INIT handler stack. To avoid + * any dependencies on the algorithm in ia64_switch_to(), just purge + * any existing CURRENT_STACK mapping and insert the new one. + */ + + mov r16=IA64_KR(CURRENT_STACK) // physical granule mapped by IA64_TR_CURRENT_STACK + ;; + shl r16=r16,IA64_GRANULE_SHIFT + ;; + dep r16=-1,r16,61,3 // virtual granule + mov r18=IA64_GRANULE_SHIFT<<2 // for cr.itir.ps + ;; + ptr.d r16,r18 + ;; + srlz.d + + shr.u r16=r20,IA64_GRANULE_SHIFT // r20 = physical start of MCA/INIT stack + movl r21=PAGE_KERNEL // page properties + ;; + mov IA64_KR(CURRENT_STACK)=r16 + or r21=r20,r21 // construct PA | page properties + ;; + mov cr.itir=r18 + mov cr.ifa=r13 + mov r20=IA64_TR_CURRENT_STACK + ;; + itr.d dtr[r20]=r21 + ;; + srlz.d br.sptk b0 diff --git a/include/asm-ia64/mca.h b/include/asm-ia64/mca.h index 97a28b8..c7d9c9e 100644 --- a/include/asm-ia64/mca.h +++ b/include/asm-ia64/mca.h @@ -80,7 +80,12 @@ struct ia64_sal_os_state { u64 sal_ra; /* Return address in SAL, physical */ u64 sal_gp; /* GP of the SAL - physical */ pal_min_state_area_t *pal_min_state; /* from R17. physical in asm, virtual in C */ + /* Previous values of IA64_KR(CURRENT) and IA64_KR(CURRENT_STACK). + * Note: if the MCA/INIT recovery code wants to resume to a new context + * then it must change these values to reflect the new kernel stack. + */ u64 prev_IA64_KR_CURRENT; /* previous value of IA64_KR(CURRENT) */ + u64 prev_IA64_KR_CURRENT_STACK; struct task_struct *prev_task; /* previous task, NULL if it is not useful */ /* Some interrupt registers are not saved in minstate, pt_regs or * switch_stack. Because MCA/INIT can occur when interrupts are |