qemu-e2k/target/ppc/cpu.c

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/*
* PowerPC CPU routines for qemu.
*
* Copyright (c) 2017 Nikunj A Dadhania, IBM Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "cpu-models.h"
#include "cpu-qom.h"
#include "exec/log.h"
#include "fpu/softfloat-helpers.h"
#include "mmu-hash64.h"
#include "helper_regs.h"
#include "sysemu/tcg.h"
target_ulong cpu_read_xer(const CPUPPCState *env)
{
if (is_isa300(env)) {
return env->xer | (env->so << XER_SO) |
(env->ov << XER_OV) | (env->ca << XER_CA) |
(env->ov32 << XER_OV32) | (env->ca32 << XER_CA32);
}
return env->xer | (env->so << XER_SO) | (env->ov << XER_OV) |
(env->ca << XER_CA);
}
void cpu_write_xer(CPUPPCState *env, target_ulong xer)
{
env->so = (xer >> XER_SO) & 1;
env->ov = (xer >> XER_OV) & 1;
env->ca = (xer >> XER_CA) & 1;
/* write all the flags, while reading back check of isa300 */
env->ov32 = (xer >> XER_OV32) & 1;
env->ca32 = (xer >> XER_CA32) & 1;
env->xer = xer & ~((1ul << XER_SO) |
(1ul << XER_OV) | (1ul << XER_CA) |
(1ul << XER_OV32) | (1ul << XER_CA32));
}
void ppc_store_vscr(CPUPPCState *env, uint32_t vscr)
{
env->vscr = vscr & ~(1u << VSCR_SAT);
/* Which bit we set is completely arbitrary, but clear the rest. */
env->vscr_sat.u64[0] = vscr & (1u << VSCR_SAT);
env->vscr_sat.u64[1] = 0;
set_flush_to_zero((vscr >> VSCR_NJ) & 1, &env->vec_status);
}
uint32_t ppc_get_vscr(CPUPPCState *env)
{
uint32_t sat = (env->vscr_sat.u64[0] | env->vscr_sat.u64[1]) != 0;
return env->vscr | (sat << VSCR_SAT);
}
/* GDBstub can read and write MSR... */
void ppc_store_msr(CPUPPCState *env, target_ulong value)
{
hreg_store_msr(env, value, 0);
}
void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
{
PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
CPUPPCState *env = &cpu->env;
env->spr[SPR_LPCR] = val & pcc->lpcr_mask;
/* The gtse bit affects hflags */
hreg_compute_hflags(env);
}
static inline void fpscr_set_rounding_mode(CPUPPCState *env)
{
int rnd_type;
/* Set rounding mode */
switch (env->fpscr & FP_RN) {
case 0:
/* Best approximation (round to nearest) */
rnd_type = float_round_nearest_even;
break;
case 1:
/* Smaller magnitude (round toward zero) */
rnd_type = float_round_to_zero;
break;
case 2:
/* Round toward +infinite */
rnd_type = float_round_up;
break;
default:
case 3:
/* Round toward -infinite */
rnd_type = float_round_down;
break;
}
set_float_rounding_mode(rnd_type, &env->fp_status);
}
void ppc_store_fpscr(CPUPPCState *env, target_ulong val)
{
val &= FPSCR_MTFS_MASK;
if (val & FPSCR_IX) {
val |= FP_VX;
}
if ((val >> FPSCR_XX) & (val >> FPSCR_XE) & 0x1f) {
val |= FP_FEX;
}
env->fpscr = val;
if (tcg_enabled()) {
fpscr_set_rounding_mode(env);
}
}