diff options
| -rw-r--r-- | linux-user/sparc/signal.c | 74 | ||||
| -rw-r--r-- | target/sparc/cpu.h | 4 |
2 files changed, 46 insertions, 32 deletions
diff --git a/linux-user/sparc/signal.c b/linux-user/sparc/signal.c index d12adc8..0057b48 100644 --- a/linux-user/sparc/signal.c +++ b/linux-user/sparc/signal.c @@ -402,8 +402,10 @@ void sparc64_set_context(CPUSPARCState *env) abi_ulong ucp_addr; struct target_ucontext *ucp; target_mc_gregset_t *grp; + target_mc_fpu_t *fpup; abi_ulong pc, npc, tstate; unsigned int i; + unsigned char fenab; ucp_addr = env->regwptr[WREG_O0]; if (!lock_user_struct(VERIFY_READ, ucp, ucp_addr, 1)) { @@ -467,26 +469,42 @@ void sparc64_set_context(CPUSPARCState *env) __get_user(env->regwptr[WREG_FP], &(ucp->tuc_mcontext.mc_fp)); __get_user(env->regwptr[WREG_I7], &(ucp->tuc_mcontext.mc_i7)); - /* FIXME this does not match how the kernel handles the FPU in - * its sparc64_set_context implementation. In particular the FPU - * is only restored if fenab is non-zero in: - * __get_user(fenab, &(ucp->tuc_mcontext.mc_fpregs.mcfpu_enab)); - */ - __get_user(env->fprs, &(ucp->tuc_mcontext.mc_fpregs.mcfpu_fprs)); - { - uint32_t *src = ucp->tuc_mcontext.mc_fpregs.mcfpu_fregs.sregs; - for (i = 0; i < 64; i++, src++) { - if (i & 1) { - __get_user(env->fpr[i/2].l.lower, src); - } else { - __get_user(env->fpr[i/2].l.upper, src); + fpup = &ucp->tuc_mcontext.mc_fpregs; + + __get_user(fenab, &(fpup->mcfpu_enab)); + if (fenab) { + abi_ulong fprs; + + /* + * We use the FPRS from the guest only in deciding whether + * to restore the upper, lower, or both banks of the FPU regs. + * The kernel here writes the FPU register data into the + * process's current_thread_info state and unconditionally + * clears FPRS and TSTATE_PEF: this disables the FPU so that the + * next FPU-disabled trap will copy the data out of + * current_thread_info and into the real FPU registers. + * QEMU doesn't need to handle lazy-FPU-state-restoring like that, + * so we always load the data directly into the FPU registers + * and leave FPRS and TSTATE_PEF alone (so the FPU stays enabled). + * Note that because we (and the kernel) always write zeroes for + * the fenab and fprs in sparc64_get_context() none of this code + * will execute unless the guest manually constructed or changed + * the context structure. + */ + __get_user(fprs, &(fpup->mcfpu_fprs)); + if (fprs & FPRS_DL) { + for (i = 0; i < 16; i++) { + __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i])); + } + } + if (fprs & FPRS_DU) { + for (i = 16; i < 32; i++) { + __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i])); } } + __get_user(env->fsr, &(fpup->mcfpu_fsr)); + __get_user(env->gsr, &(fpup->mcfpu_gsr)); } - __get_user(env->fsr, - &(ucp->tuc_mcontext.mc_fpregs.mcfpu_fsr)); - __get_user(env->gsr, - &(ucp->tuc_mcontext.mc_fpregs.mcfpu_gsr)); unlock_user_struct(ucp, ucp_addr, 0); return; do_sigsegv: @@ -509,7 +527,9 @@ void sparc64_get_context(CPUSPARCState *env) if (!lock_user_struct(VERIFY_WRITE, ucp, ucp_addr, 0)) { goto do_sigsegv; } - + + memset(ucp, 0, sizeof(*ucp)); + mcp = &ucp->tuc_mcontext; grp = &mcp->mc_gregs; @@ -572,19 +592,11 @@ void sparc64_get_context(CPUSPARCState *env) __put_user(env->regwptr[WREG_FP], &(mcp->mc_fp)); __put_user(env->regwptr[WREG_I7], &(mcp->mc_i7)); - { - uint32_t *dst = ucp->tuc_mcontext.mc_fpregs.mcfpu_fregs.sregs; - for (i = 0; i < 64; i++, dst++) { - if (i & 1) { - __put_user(env->fpr[i/2].l.lower, dst); - } else { - __put_user(env->fpr[i/2].l.upper, dst); - } - } - } - __put_user(env->fsr, &(mcp->mc_fpregs.mcfpu_fsr)); - __put_user(env->gsr, &(mcp->mc_fpregs.mcfpu_gsr)); - __put_user(env->fprs, &(mcp->mc_fpregs.mcfpu_fprs)); + /* + * We don't write out the FPU state. This matches the kernel's + * implementation (which has the code for doing this but + * hidden behind an "if (fenab)" where fenab is always 0). + */ if (err) goto do_sigsegv; diff --git a/target/sparc/cpu.h b/target/sparc/cpu.h index b936939..2772547 100644 --- a/target/sparc/cpu.h +++ b/target/sparc/cpu.h @@ -156,7 +156,9 @@ enum { #define PS_IE (1<<1) #define PS_AG (1<<0) /* v9, zero on UA2007 */ -#define FPRS_FEF (1<<2) +#define FPRS_DL (1 << 0) +#define FPRS_DU (1 << 1) +#define FPRS_FEF (1 << 2) #define HS_PRIV (1<<2) #endif |