diff options
Diffstat (limited to 'qemu/roms/openbios/arch/sparc64/cpustate.h')
| -rw-r--r-- | qemu/roms/openbios/arch/sparc64/cpustate.h | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/qemu/roms/openbios/arch/sparc64/cpustate.h b/qemu/roms/openbios/arch/sparc64/cpustate.h new file mode 100644 index 000000000..0c276bfd1 --- /dev/null +++ b/qemu/roms/openbios/arch/sparc64/cpustate.h @@ -0,0 +1,244 @@ +/* + * Save/restore CPU state macros + * + * Copyright (C) 2015 Mark Cave-Ayland (mark.cave-ayland@ilande.co.uk>) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 + * + */ + +/* State size for context (see below) */ +#define CONTEXT_STATE_SIZE 0x510 + +/* Stack size for context (allocated inline of the context stack) */ +#define CONTEXT_STACK_SIZE 0x2000 + +/* + * SAVE_CPU_STATE and RESTORE_CPU_STATE are macros used to enable a context switch + * to C to occur within the MMU I/D TLB miss handlers. + * + * Because these handlers are called on a TLB miss, we cannot use flushw to store + * processor window state on the stack, as the memory areas used by each window's + * stack pointer may not be in the TLB, causing recursive TLB miss traps. + * + * For this reason, we save window state by manually rotating the window registers + * and saving their contents (along with other vital registers) into a special + * tlb_handler_stack defined above which is guaranteed to be locked in the TLB, and + * so won't cause issues with trap recursion. + * + * Once this process is complete, we remain in a TL=0, CWP=0 state (with IE=1 to allow + * window fill/spill traps if required), switch to our safe tlb_handler_stack and + * invoke the miss handler. + */ + +#define SAVE_CPU_WINDOW_STATE(type) \ + /* Save window state into context at %g1 */ \ + rdpr %cwp, %g7; \ + stx %g7, [%g1]; \ + rdpr %cansave, %g7; \ + stx %g7, [%g1 + 0x8]; \ + rdpr %canrestore, %g7; \ + stx %g7, [%g1 + 0x10]; \ + rdpr %otherwin, %g7; \ + stx %g7, [%g1 + 0x18]; \ + rdpr %wstate, %g7; \ + stx %g7, [%g1 + 0x20]; \ + rdpr %cleanwin, %g7; \ + stx %g7, [%g1 + 0x28]; \ + \ + stx %o0, [%g1 + 0x30]; \ + stx %o1, [%g1 + 0x38]; \ + stx %o2, [%g1 + 0x40]; \ + stx %o3, [%g1 + 0x48]; \ + stx %o4, [%g1 + 0x50]; \ + stx %o5, [%g1 + 0x58]; \ + stx %o6, [%g1 + 0x60]; \ + stx %o7, [%g1 + 0x68]; \ + \ + rdpr %pstate, %g7; \ + stx %g7, [%g1 + 0x70]; \ + rd %y, %g7; \ + stx %g7, [%g1 + 0x78]; \ + rd %fprs, %g7; \ + stx %g7, [%g1 + 0x80]; \ + rdpr %tl, %g7; \ + stx %g7, [%g1 + 0x88]; \ + \ + /* Now iterate through all of the windows saving all l and i registers */ \ + add %g1, 0x90, %g5; \ + \ + /* Get the number of windows in %g6 */ \ + rdpr %ver, %g6; \ + and %g6, 0xf, %g6; \ + \ + mov %g6, %g4; \ + inc %g4; \ + \ + /* Starting cwp in g7 */ \ + rdpr %cwp, %g7; \ + \ +save_cpu_window_##type: \ + wrpr %g7, %cwp; \ + stx %l0, [%g5]; \ + stx %l1, [%g5 + 0x8]; \ + stx %l2, [%g5 + 0x10]; \ + stx %l3, [%g5 + 0x18]; \ + stx %l4, [%g5 + 0x20]; \ + stx %l5, [%g5 + 0x28]; \ + stx %l6, [%g5 + 0x30]; \ + stx %l7, [%g5 + 0x38]; \ + stx %i0, [%g5 + 0x40]; \ + stx %i1, [%g5 + 0x48]; \ + stx %i2, [%g5 + 0x50]; \ + stx %i3, [%g5 + 0x58]; \ + stx %i4, [%g5 + 0x60]; \ + stx %i5, [%g5 + 0x68]; \ + stx %i6, [%g5 + 0x70]; \ + stx %i7, [%g5 + 0x78]; \ + dec %g7; \ + and %g7, %g6, %g7; \ + subcc %g4, 1, %g4; \ + bne save_cpu_window_##type; \ + add %g5, 0x80, %g5; \ + \ + /* For 8 windows with 16 registers to save in the window, memory required \ + is 16*8*8 = 0x400 bytes */ \ + \ + /* Now we should be in window 0 so update the other window registers */ \ + rdpr %ver, %g6; \ + and %g6, 0xf, %g6; \ + dec %g6; \ + wrpr %g6, %cansave; \ + \ + wrpr %g0, %cleanwin; \ + wrpr %g0, %canrestore; \ + wrpr %g0, %otherwin; \ + + +#define SAVE_CPU_TRAP_STATE(type) \ + /* Save trap state into context at %g1 */ \ + add %g1, 0x490, %g5; \ + mov 4, %g6; \ + \ +save_trap_state_##type: \ + deccc %g6; \ + wrpr %g6, %tl; \ + rdpr %tpc, %g7; \ + stx %g7, [%g5]; \ + rdpr %tnpc, %g7; \ + stx %g7, [%g5 + 0x8]; \ + rdpr %tstate, %g7; \ + stx %g7, [%g5 + 0x10]; \ + rdpr %tt, %g7; \ + stx %g7, [%g5 + 0x18]; \ + bne save_trap_state_##type; \ + add %g5, 0x20, %g5; \ + \ + /* For 4 trap levels with 4 registers, memory required is \ + 4*8*4 = 0x80 bytes */ + +/* Save all state into context at %g1 */ +#define SAVE_CPU_STATE(type) \ + SAVE_CPU_WINDOW_STATE(type); \ + SAVE_CPU_TRAP_STATE(type); + + +#define RESTORE_CPU_WINDOW_STATE(type) \ + /* Restore window state from context at %g1 */ \ + \ + /* Get the number of windows in %g6 */ \ + rdpr %ver, %g6; \ + and %g6, 0xf, %g6; \ + \ + mov %g6, %g4; \ + inc %g4; \ + \ + /* Set starting window */ \ + ldx [%g1], %g7; \ + \ + /* Now iterate through all of the windows restoring all l and i registers */ \ + add %g1, 0x90, %g5; \ + \ +restore_cpu_window_##type: \ + wrpr %g7, %cwp; \ + ldx [%g5], %l0; \ + ldx [%g5 + 0x8], %l1; \ + ldx [%g5 + 0x10], %l2; \ + ldx [%g5 + 0x18], %l3; \ + ldx [%g5 + 0x20], %l4; \ + ldx [%g5 + 0x28], %l5; \ + ldx [%g5 + 0x30], %l6; \ + ldx [%g5 + 0x38], %l7; \ + ldx [%g5 + 0x40], %i0; \ + ldx [%g5 + 0x48], %i1; \ + ldx [%g5 + 0x50], %i2; \ + ldx [%g5 + 0x58], %i3; \ + ldx [%g5 + 0x60], %i4; \ + ldx [%g5 + 0x68], %i5; \ + ldx [%g5 + 0x70], %i6; \ + ldx [%g5 + 0x78], %i7; \ + dec %g7; \ + and %g7, %g6, %g7; \ + subcc %g4, 1, %g4; \ + bne restore_cpu_window_##type; \ + add %g5, 0x80, %g5; \ + \ + /* Restore the window registers to their original value */ \ + ldx [%g1], %g7; \ + wrpr %g7, %cwp; \ + ldx [%g1 + 0x8], %g7; \ + wrpr %g7, %cansave; \ + ldx [%g1 + 0x10], %g7; \ + wrpr %g7, %canrestore; \ + ldx [%g1 + 0x18], %g7; \ + wrpr %g7, %otherwin; \ + ldx [%g1 + 0x20], %g7; \ + wrpr %g7, %wstate; \ + ldx [%g1 + 0x28], %g7; \ + wrpr %g7, %cleanwin; \ + \ + ldx [%g1 + 0x30], %o0; \ + ldx [%g1 + 0x38], %o1; \ + ldx [%g1 + 0x40], %o2; \ + ldx [%g1 + 0x48], %o3; \ + ldx [%g1 + 0x50], %o4; \ + ldx [%g1 + 0x58], %o5; \ + ldx [%g1 + 0x60], %o6; \ + ldx [%g1 + 0x68], %o7; \ + \ + ldx [%g1 + 0x70], %g7; \ + wrpr %g7, %pstate; \ + ldx [%g1 + 0x78], %g7; \ + wr %g7, 0, %y; \ + ldx [%g1 + 0x80], %g7; \ + wr %g7, 0, %fprs; \ + + +#define RESTORE_CPU_TRAP_STATE(type) \ + /* Restore trap state from context at %g1 */ \ + add %g1, 0x490, %g5; \ + mov 4, %g6; \ + \ +restore_trap_state_##type: \ + deccc %g6; \ + wrpr %g6, %tl; \ + ldx [%g5], %g7; \ + wrpr %g7, %tpc; \ + ldx [%g5 + 0x8], %g7; \ + wrpr %g7, %tnpc; \ + ldx [%g5 + 0x10], %g7; \ + wrpr %g7, %tstate; \ + ldx [%g5 + 0x18], %g7; \ + wrpr %g7, %tt; \ + bne restore_trap_state_##type; \ + add %g5, 0x20, %g5; \ + \ + ldx [%g1 + 0x88], %g7; \ + wrpr %g7, %tl + +/* Restore all state from context at %g1 */ +#define RESTORE_CPU_STATE(type) \ + RESTORE_CPU_WINDOW_STATE(type); \ + RESTORE_CPU_TRAP_STATE(type); |