qemu-e2k/target/openrisc/machine.c
Stafford Horne f4d1414a93 target/openrisc: Support non-busy idle state using PMR SPR
The OpenRISC architecture has the Power Management Register (PMR)
special purpose register to manage cpu power states.  The interesting
modes are:

 * Doze Mode (DME) - Stop cpu except timer & pic - wake on interrupt
 * Sleep Mode (SME) - Stop cpu and all units - wake on interrupt
 * Suspend Model (SUME) - Stop cpu and all units - wake on reset

The linux kernel will set DME when idle.

This patch implements the PMR SPR and halts the qemu cpu when there is a
change to DME or SME.  This means that openrisc qemu in no longer peggs
a host cpu at 100%.

In order for this to work we need to kick the CPU when timers are
expired.  Update the cpu timer to kick the cpu upon each timer event.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-05-04 09:39:14 +09:00

169 lines
5.2 KiB
C

/*
* OpenRISC Machine
*
* Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com>
*
* 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 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 "qemu-common.h"
#include "cpu.h"
#include "hw/hw.h"
#include "hw/boards.h"
#include "migration/cpu.h"
static int env_post_load(void *opaque, int version_id)
{
CPUOpenRISCState *env = opaque;
/* Restore MMU handlers */
if (env->sr & SR_DME) {
env->tlb->cpu_openrisc_map_address_data =
&cpu_openrisc_get_phys_data;
} else {
env->tlb->cpu_openrisc_map_address_data =
&cpu_openrisc_get_phys_nommu;
}
if (env->sr & SR_IME) {
env->tlb->cpu_openrisc_map_address_code =
&cpu_openrisc_get_phys_code;
} else {
env->tlb->cpu_openrisc_map_address_code =
&cpu_openrisc_get_phys_nommu;
}
return 0;
}
static const VMStateDescription vmstate_tlb_entry = {
.name = "tlb_entry",
.version_id = 1,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.fields = (VMStateField[]) {
VMSTATE_UINTTL(mr, OpenRISCTLBEntry),
VMSTATE_UINTTL(tr, OpenRISCTLBEntry),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_cpu_tlb = {
.name = "cpu_tlb",
.version_id = 1,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.fields = (VMStateField[]) {
VMSTATE_STRUCT_2DARRAY(itlb, CPUOpenRISCTLBContext,
ITLB_WAYS, ITLB_SIZE, 0,
vmstate_tlb_entry, OpenRISCTLBEntry),
VMSTATE_STRUCT_2DARRAY(dtlb, CPUOpenRISCTLBContext,
DTLB_WAYS, DTLB_SIZE, 0,
vmstate_tlb_entry, OpenRISCTLBEntry),
VMSTATE_END_OF_LIST()
}
};
#define VMSTATE_CPU_TLB(_f, _s) \
VMSTATE_STRUCT_POINTER(_f, _s, vmstate_cpu_tlb, CPUOpenRISCTLBContext)
static int get_sr(QEMUFile *f, void *opaque, size_t size, VMStateField *field)
{
CPUOpenRISCState *env = opaque;
cpu_set_sr(env, qemu_get_be32(f));
return 0;
}
static int put_sr(QEMUFile *f, void *opaque, size_t size,
VMStateField *field, QJSON *vmdesc)
{
CPUOpenRISCState *env = opaque;
qemu_put_be32(f, cpu_get_sr(env));
return 0;
}
static const VMStateInfo vmstate_sr = {
.name = "sr",
.get = get_sr,
.put = put_sr,
};
static const VMStateDescription vmstate_env = {
.name = "env",
.version_id = 6,
.minimum_version_id = 6,
.post_load = env_post_load,
.fields = (VMStateField[]) {
VMSTATE_UINTTL_2DARRAY(shadow_gpr, CPUOpenRISCState, 16, 32),
VMSTATE_UINTTL(pc, CPUOpenRISCState),
VMSTATE_UINTTL(ppc, CPUOpenRISCState),
VMSTATE_UINTTL(jmp_pc, CPUOpenRISCState),
VMSTATE_UINTTL(lock_addr, CPUOpenRISCState),
VMSTATE_UINTTL(lock_value, CPUOpenRISCState),
VMSTATE_UINTTL(epcr, CPUOpenRISCState),
VMSTATE_UINTTL(eear, CPUOpenRISCState),
/* Save the architecture value of the SR, not the internally
expanded version. Since this architecture value does not
exist in memory to be stored, this requires a but of hoop
jumping. We want OFFSET=0 so that we effectively pass ENV
to the helper functions, and we need to fill in the name by
hand since there's no field of that name. */
{
.name = "sr",
.version_id = 0,
.size = sizeof(uint32_t),
.info = &vmstate_sr,
.flags = VMS_SINGLE,
.offset = 0
},
VMSTATE_UINT32(vr, CPUOpenRISCState),
VMSTATE_UINT32(upr, CPUOpenRISCState),
VMSTATE_UINT32(cpucfgr, CPUOpenRISCState),
VMSTATE_UINT32(dmmucfgr, CPUOpenRISCState),
VMSTATE_UINT32(immucfgr, CPUOpenRISCState),
VMSTATE_UINT32(evbar, CPUOpenRISCState),
VMSTATE_UINT32(pmr, CPUOpenRISCState),
VMSTATE_UINT32(esr, CPUOpenRISCState),
VMSTATE_UINT32(fpcsr, CPUOpenRISCState),
VMSTATE_UINT64(mac, CPUOpenRISCState),
VMSTATE_CPU_TLB(tlb, CPUOpenRISCState),
VMSTATE_TIMER_PTR(timer, CPUOpenRISCState),
VMSTATE_UINT32(ttmr, CPUOpenRISCState),
VMSTATE_UINT32(ttcr, CPUOpenRISCState),
VMSTATE_UINT32(picmr, CPUOpenRISCState),
VMSTATE_UINT32(picsr, CPUOpenRISCState),
VMSTATE_END_OF_LIST()
}
};
const VMStateDescription vmstate_openrisc_cpu = {
.name = "cpu",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_CPU(),
VMSTATE_STRUCT(env, OpenRISCCPU, 1, vmstate_env, CPUOpenRISCState),
VMSTATE_END_OF_LIST()
}
};