linux/linux-5.4.31/arch/sparc/kernel/etrap_64.S

285 lines
7.1 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* etrap.S: Preparing for entry into the kernel on Sparc V9.
*
* Copyright (C) 1996, 1997 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1997, 1998, 1999 Jakub Jelinek (jj@ultra.linux.cz)
*/
#include <asm/asi.h>
#include <asm/pstate.h>
#include <asm/ptrace.h>
#include <asm/page.h>
#include <asm/spitfire.h>
#include <asm/head.h>
#include <asm/processor.h>
#include <asm/mmu.h>
#define TASK_REGOFF (THREAD_SIZE-TRACEREG_SZ-STACKFRAME_SZ)
#define ETRAP_PSTATE1 (PSTATE_TSO | PSTATE_PRIV)
#define ETRAP_PSTATE2 \
(PSTATE_TSO | PSTATE_PEF | PSTATE_PRIV | PSTATE_IE)
/*
* On entry, %g7 is return address - 0x4.
* %g4 and %g5 will be preserved %l4 and %l5 respectively.
*/
.text
.align 64
.globl etrap_syscall, etrap, etrap_irq, etraptl1
etrap: rdpr %pil, %g2
etrap_irq: clr %g3
etrap_syscall: TRAP_LOAD_THREAD_REG(%g6, %g1)
rdpr %tstate, %g1
or %g1, %g3, %g1
sllx %g2, 20, %g3
andcc %g1, TSTATE_PRIV, %g0
or %g1, %g3, %g1
bne,pn %xcc, 1f
sub %sp, STACKFRAME_SZ+TRACEREG_SZ-STACK_BIAS, %g2
661: wrpr %g0, 7, %cleanwin
.section .fast_win_ctrl_1insn_patch, "ax"
.word 661b
.word 0x85880000 ! allclean
.previous
sethi %hi(TASK_REGOFF), %g2
sethi %hi(TSTATE_PEF), %g3
or %g2, %lo(TASK_REGOFF), %g2
and %g1, %g3, %g3
brnz,pn %g3, 1f
add %g6, %g2, %g2
wr %g0, 0, %fprs
1: rdpr %tpc, %g3
stx %g1, [%g2 + STACKFRAME_SZ + PT_V9_TSTATE]
rdpr %tnpc, %g1
stx %g3, [%g2 + STACKFRAME_SZ + PT_V9_TPC]
rd %y, %g3
stx %g1, [%g2 + STACKFRAME_SZ + PT_V9_TNPC]
rdpr %tt, %g1
st %g3, [%g2 + STACKFRAME_SZ + PT_V9_Y]
sethi %hi(PT_REGS_MAGIC), %g3
or %g3, %g1, %g1
st %g1, [%g2 + STACKFRAME_SZ + PT_V9_MAGIC]
rdpr %cansave, %g1
brnz,pt %g1, etrap_save
nop
rdpr %cwp, %g1
add %g1, 2, %g1
wrpr %g1, %cwp
be,pt %xcc, etrap_user_spill
mov ASI_AIUP, %g3
rdpr %otherwin, %g3
brz %g3, etrap_kernel_spill
mov ASI_AIUS, %g3
etrap_user_spill:
wr %g3, 0x0, %asi
ldx [%g6 + TI_FLAGS], %g3
and %g3, _TIF_32BIT, %g3
brnz,pt %g3, etrap_user_spill_32bit
nop
ba,a,pt %xcc, etrap_user_spill_64bit
etrap_save: save %g2, -STACK_BIAS, %sp
mov %g6, %l6
bne,pn %xcc, 3f
mov PRIMARY_CONTEXT, %l4
661: rdpr %canrestore, %g3
.section .fast_win_ctrl_1insn_patch, "ax"
.word 661b
nop
.previous
rdpr %wstate, %g2
661: wrpr %g0, 0, %canrestore
.section .fast_win_ctrl_1insn_patch, "ax"
.word 661b
nop
.previous
sll %g2, 3, %g2
/* Set TI_SYS_FPDEPTH to 1 and clear TI_SYS_NOERROR. */
mov 1, %l5
sth %l5, [%l6 + TI_SYS_NOERROR]
661: wrpr %g3, 0, %otherwin
.section .fast_win_ctrl_1insn_patch, "ax"
.word 661b
.word 0x87880000 ! otherw
.previous
wrpr %g2, 0, %wstate
sethi %hi(sparc64_kern_pri_context), %g2
ldx [%g2 + %lo(sparc64_kern_pri_context)], %g3
661: stxa %g3, [%l4] ASI_DMMU
.section .sun4v_1insn_patch, "ax"
.word 661b
stxa %g3, [%l4] ASI_MMU
.previous
sethi %hi(KERNBASE), %l4
flush %l4
mov ASI_AIUS, %l7
2: mov %g4, %l4
mov %g5, %l5
add %g7, 4, %l2
/* Go to trap time globals so we can save them. */
661: wrpr %g0, ETRAP_PSTATE1, %pstate
.section .sun4v_1insn_patch, "ax"
.word 661b
SET_GL(0)
.previous
stx %g1, [%sp + PTREGS_OFF + PT_V9_G1]
stx %g2, [%sp + PTREGS_OFF + PT_V9_G2]
sllx %l7, 24, %l7
stx %g3, [%sp + PTREGS_OFF + PT_V9_G3]
rdpr %cwp, %l0
stx %g4, [%sp + PTREGS_OFF + PT_V9_G4]
stx %g5, [%sp + PTREGS_OFF + PT_V9_G5]
stx %g6, [%sp + PTREGS_OFF + PT_V9_G6]
stx %g7, [%sp + PTREGS_OFF + PT_V9_G7]
or %l7, %l0, %l7
661: sethi %hi(TSTATE_TSO | TSTATE_PEF), %l0
/* If userspace is using ADI, it could potentially pass
* a pointer with version tag embedded in it. To maintain
* the ADI security, we must enable PSTATE.mcde. Userspace
* would have already set TTE.mcd in an earlier call to
* kernel and set the version tag for the address being
* dereferenced. Setting PSTATE.mcde would ensure any
* access to userspace data through a system call honors
* ADI and does not allow a rogue app to bypass ADI by
* using system calls. Setting PSTATE.mcde only affects
* accesses to virtual addresses that have TTE.mcd set.
* Set PMCDPER to ensure any exceptions caused by ADI
* version tag mismatch are exposed before system call
* returns to userspace. Setting PMCDPER affects only
* writes to virtual addresses that have TTE.mcd set and
* have a version tag set as well.
*/
.section .sun_m7_1insn_patch, "ax"
.word 661b
sethi %hi(TSTATE_TSO | TSTATE_PEF | TSTATE_MCDE), %l0
.previous
661: nop
.section .sun_m7_1insn_patch, "ax"
.word 661b
.word 0xaf902001 /* wrpr %g0, 1, %pmcdper */
.previous
or %l7, %l0, %l7
wrpr %l2, %tnpc
wrpr %l7, (TSTATE_PRIV | TSTATE_IE), %tstate
stx %i0, [%sp + PTREGS_OFF + PT_V9_I0]
stx %i1, [%sp + PTREGS_OFF + PT_V9_I1]
stx %i2, [%sp + PTREGS_OFF + PT_V9_I2]
stx %i3, [%sp + PTREGS_OFF + PT_V9_I3]
stx %i4, [%sp + PTREGS_OFF + PT_V9_I4]
stx %i5, [%sp + PTREGS_OFF + PT_V9_I5]
stx %i6, [%sp + PTREGS_OFF + PT_V9_I6]
mov %l6, %g6
stx %i7, [%sp + PTREGS_OFF + PT_V9_I7]
LOAD_PER_CPU_BASE(%g5, %g6, %g4, %g3, %l1)
ldx [%g6 + TI_TASK], %g4
done
3: mov ASI_P, %l7
ldub [%l6 + TI_FPDEPTH], %l5
add %l6, TI_FPSAVED + 1, %l4
srl %l5, 1, %l3
add %l5, 2, %l5
/* Set TI_SYS_FPDEPTH to %l5 and clear TI_SYS_NOERROR. */
sth %l5, [%l6 + TI_SYS_NOERROR]
ba,pt %xcc, 2b
stb %g0, [%l4 + %l3]
nop
etraptl1: /* Save tstate/tpc/tnpc of TL 1-->4 and the tl register itself.
* We place this right after pt_regs on the trap stack.
* The layout is:
* 0x00 TL1's TSTATE
* 0x08 TL1's TPC
* 0x10 TL1's TNPC
* 0x18 TL1's TT
* ...
* 0x58 TL4's TT
* 0x60 TL
*/
TRAP_LOAD_THREAD_REG(%g6, %g1)
sub %sp, ((4 * 8) * 4) + 8, %g2
rdpr %tl, %g1
wrpr %g0, 1, %tl
rdpr %tstate, %g3
stx %g3, [%g2 + STACK_BIAS + 0x00]
rdpr %tpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x08]
rdpr %tnpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x10]
rdpr %tt, %g3
stx %g3, [%g2 + STACK_BIAS + 0x18]
wrpr %g0, 2, %tl
rdpr %tstate, %g3
stx %g3, [%g2 + STACK_BIAS + 0x20]
rdpr %tpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x28]
rdpr %tnpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x30]
rdpr %tt, %g3
stx %g3, [%g2 + STACK_BIAS + 0x38]
sethi %hi(is_sun4v), %g3
lduw [%g3 + %lo(is_sun4v)], %g3
brnz,pn %g3, finish_tl1_capture
nop
wrpr %g0, 3, %tl
rdpr %tstate, %g3
stx %g3, [%g2 + STACK_BIAS + 0x40]
rdpr %tpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x48]
rdpr %tnpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x50]
rdpr %tt, %g3
stx %g3, [%g2 + STACK_BIAS + 0x58]
wrpr %g0, 4, %tl
rdpr %tstate, %g3
stx %g3, [%g2 + STACK_BIAS + 0x60]
rdpr %tpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x68]
rdpr %tnpc, %g3
stx %g3, [%g2 + STACK_BIAS + 0x70]
rdpr %tt, %g3
stx %g3, [%g2 + STACK_BIAS + 0x78]
stx %g1, [%g2 + STACK_BIAS + 0x80]
finish_tl1_capture:
wrpr %g0, 1, %tl
661: nop
.section .sun4v_1insn_patch, "ax"
.word 661b
SET_GL(1)
.previous
rdpr %tstate, %g1
sub %g2, STACKFRAME_SZ + TRACEREG_SZ - STACK_BIAS, %g2
ba,pt %xcc, 1b
andcc %g1, TSTATE_PRIV, %g0
#undef TASK_REGOFF
#undef ETRAP_PSTATE1