qemu/hw/ppce500_spin.c
Stefan Weil 5f2c23e61a ppce500_spin: Replace assert by hw_error (fixes compiler warning)
The default case in function spin_read should never be reached,
therefore the old code used assert(0) to abort QEMU.

This does not work when QEMU is compiled with macro NDEBUG defined.
In this case (and also when the compiler does not know that assert
never returns), there is a compiler warning because of the missing
return value.

Using hw_error allows an improved error message and aborts always.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
[agraf: use __func__]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-01 21:47:01 +02:00

227 lines
5.7 KiB
C

/*
* QEMU PowerPC e500v2 ePAPR spinning code
*
* Copyright (C) 2011 Freescale Semiconductor, Inc. All rights reserved.
*
* Author: Alexander Graf, <agraf@suse.de>
*
* 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/>.
*
* This code is not really a device, but models an interface that usually
* firmware takes care of. It's used when QEMU plays the role of firmware.
*
* Specification:
*
* https://www.power.org/resources/downloads/Power_ePAPR_APPROVED_v1.1.pdf
*
*/
#include "hw.h"
#include "sysemu.h"
#include "sysbus.h"
#include "kvm.h"
#define MAX_CPUS 32
typedef struct spin_info {
uint64_t addr;
uint64_t r3;
uint32_t resv;
uint32_t pir;
uint64_t reserved;
} __attribute__ ((packed)) SpinInfo;
typedef struct spin_state {
SysBusDevice busdev;
MemoryRegion iomem;
SpinInfo spin[MAX_CPUS];
} SpinState;
typedef struct spin_kick {
CPUPPCState *env;
SpinInfo *spin;
} SpinKick;
static void spin_reset(void *opaque)
{
SpinState *s = opaque;
int i;
for (i = 0; i < MAX_CPUS; i++) {
SpinInfo *info = &s->spin[i];
info->pir = i;
info->r3 = i;
info->addr = 1;
}
}
/* Create -kernel TLB entries for BookE, linearly spanning 256MB. */
static inline target_phys_addr_t booke206_page_size_to_tlb(uint64_t size)
{
return (ffs(size >> 10) - 1) >> 1;
}
static void mmubooke_create_initial_mapping(CPUPPCState *env,
target_ulong va,
target_phys_addr_t pa,
target_phys_addr_t len)
{
ppcmas_tlb_t *tlb = booke206_get_tlbm(env, 1, 0, 1);
target_phys_addr_t size;
size = (booke206_page_size_to_tlb(len) << MAS1_TSIZE_SHIFT);
tlb->mas1 = MAS1_VALID | size;
tlb->mas2 = (va & TARGET_PAGE_MASK) | MAS2_M;
tlb->mas7_3 = pa & TARGET_PAGE_MASK;
tlb->mas7_3 |= MAS3_UR | MAS3_UW | MAS3_UX | MAS3_SR | MAS3_SW | MAS3_SX;
env->tlb_dirty = true;
}
static void spin_kick(void *data)
{
SpinKick *kick = data;
CPUPPCState *env = kick->env;
SpinInfo *curspin = kick->spin;
target_phys_addr_t map_size = 64 * 1024 * 1024;
target_phys_addr_t map_start;
cpu_synchronize_state(env);
stl_p(&curspin->pir, env->spr[SPR_PIR]);
env->nip = ldq_p(&curspin->addr) & (map_size - 1);
env->gpr[3] = ldq_p(&curspin->r3);
env->gpr[4] = 0;
env->gpr[5] = 0;
env->gpr[6] = 0;
env->gpr[7] = map_size;
env->gpr[8] = 0;
env->gpr[9] = 0;
map_start = ldq_p(&curspin->addr) & ~(map_size - 1);
mmubooke_create_initial_mapping(env, 0, map_start, map_size);
env->halted = 0;
env->exception_index = -1;
env->stopped = 0;
qemu_cpu_kick(env);
}
static void spin_write(void *opaque, target_phys_addr_t addr, uint64_t value,
unsigned len)
{
SpinState *s = opaque;
int env_idx = addr / sizeof(SpinInfo);
CPUPPCState *env;
SpinInfo *curspin = &s->spin[env_idx];
uint8_t *curspin_p = (uint8_t*)curspin;
for (env = first_cpu; env != NULL; env = env->next_cpu) {
if (env->cpu_index == env_idx) {
break;
}
}
if (!env) {
/* Unknown CPU */
return;
}
if (!env->cpu_index) {
/* primary CPU doesn't spin */
return;
}
curspin_p = &curspin_p[addr % sizeof(SpinInfo)];
switch (len) {
case 1:
stb_p(curspin_p, value);
break;
case 2:
stw_p(curspin_p, value);
break;
case 4:
stl_p(curspin_p, value);
break;
}
if (!(ldq_p(&curspin->addr) & 1)) {
/* run CPU */
SpinKick kick = {
.env = env,
.spin = curspin,
};
run_on_cpu(env, spin_kick, &kick);
}
}
static uint64_t spin_read(void *opaque, target_phys_addr_t addr, unsigned len)
{
SpinState *s = opaque;
uint8_t *spin_p = &((uint8_t*)s->spin)[addr];
switch (len) {
case 1:
return ldub_p(spin_p);
case 2:
return lduw_p(spin_p);
case 4:
return ldl_p(spin_p);
default:
hw_error("ppce500: unexpected %s with len = %u", __func__, len);
}
}
static const MemoryRegionOps spin_rw_ops = {
.read = spin_read,
.write = spin_write,
.endianness = DEVICE_BIG_ENDIAN,
};
static int ppce500_spin_initfn(SysBusDevice *dev)
{
SpinState *s;
s = FROM_SYSBUS(SpinState, sysbus_from_qdev(dev));
memory_region_init_io(&s->iomem, &spin_rw_ops, s, "e500 spin pv device",
sizeof(SpinInfo) * MAX_CPUS);
sysbus_init_mmio(dev, &s->iomem);
qemu_register_reset(spin_reset, s);
return 0;
}
static void ppce500_spin_class_init(ObjectClass *klass, void *data)
{
SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
k->init = ppce500_spin_initfn;
}
static TypeInfo ppce500_spin_info = {
.name = "e500-spin",
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(SpinState),
.class_init = ppce500_spin_class_init,
};
static void ppce500_spin_register_types(void)
{
type_register_static(&ppce500_spin_info);
}
type_init(ppce500_spin_register_types)