/*
* QEMU PowerPC Booke hardware System Emulator
*
* Copyright (c) 2011 AdaCore
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "hw/ppc/ppc.h"
#include "qemu/timer.h"
#include "sysemu/reset.h"
#include "sysemu/runstate.h"
#include "qemu/log.h"
#include "hw/loader.h"
#include "kvm_ppc.h"
/* Timer Control Register */
#define TCR_WP_SHIFT 30 /* Watchdog Timer Period */
#define TCR_WP_MASK (0x3U << TCR_WP_SHIFT)
#define TCR_WRC_SHIFT 28 /* Watchdog Timer Reset Control */
#define TCR_WRC_MASK (0x3U << TCR_WRC_SHIFT)
#define TCR_WIE (1U << 27) /* Watchdog Timer Interrupt Enable */
#define TCR_DIE (1U << 26) /* Decrementer Interrupt Enable */
#define TCR_FP_SHIFT 24 /* Fixed-Interval Timer Period */
#define TCR_FP_MASK (0x3U << TCR_FP_SHIFT)
#define TCR_FIE (1U << 23) /* Fixed-Interval Timer Interrupt Enable */
#define TCR_ARE (1U << 22) /* Auto-Reload Enable */
/* Timer Control Register (e500 specific fields) */
#define TCR_E500_FPEXT_SHIFT 13 /* Fixed-Interval Timer Period Extension */
#define TCR_E500_FPEXT_MASK (0xf << TCR_E500_FPEXT_SHIFT)
#define TCR_E500_WPEXT_SHIFT 17 /* Watchdog Timer Period Extension */
#define TCR_E500_WPEXT_MASK (0xf << TCR_E500_WPEXT_SHIFT)
/* Timer Status Register */
#define TSR_FIS (1U << 26) /* Fixed-Interval Timer Interrupt Status */
#define TSR_DIS (1U << 27) /* Decrementer Interrupt Status */
#define TSR_WRS_SHIFT 28 /* Watchdog Timer Reset Status */
#define TSR_WRS_MASK (0x3U << TSR_WRS_SHIFT)
#define TSR_WIS (1U << 30) /* Watchdog Timer Interrupt Status */
#define TSR_ENW (1U << 31) /* Enable Next Watchdog Timer */
typedef struct booke_timer_t booke_timer_t;
struct booke_timer_t {
uint64_t fit_next;
QEMUTimer *fit_timer;
uint64_t wdt_next;
QEMUTimer *wdt_timer;
uint32_t flags;
};
static void booke_update_irq(PowerPCCPU *cpu)
{
CPUPPCState *env = &cpu->env;
ppc_set_irq(cpu, PPC_INTERRUPT_DECR,
(env->spr[SPR_BOOKE_TSR] & TSR_DIS
&& env->spr[SPR_BOOKE_TCR] & TCR_DIE));
ppc_set_irq(cpu, PPC_INTERRUPT_WDT,
(env->spr[SPR_BOOKE_TSR] & TSR_WIS
&& env->spr[SPR_BOOKE_TCR] & TCR_WIE));
ppc_set_irq(cpu, PPC_INTERRUPT_FIT,
(env->spr[SPR_BOOKE_TSR] & TSR_FIS
&& env->spr[SPR_BOOKE_TCR] & TCR_FIE));
}
/* Return the location of the bit of time base at which the FIT will raise an
interrupt */
static uint8_t booke_get_fit_target(CPUPPCState *env, ppc_tb_t *tb_env)
{
uint8_t fp = (env->spr[SPR_BOOKE_TCR] & TCR_FP_MASK) >> TCR_FP_SHIFT;
if (tb_env->flags & PPC_TIMER_E500) {
/* e500 Fixed-interval timer period extension */
uint32_t fpext = (env->spr[SPR_BOOKE_TCR] & TCR_E500_FPEXT_MASK)
>> TCR_E500_FPEXT_SHIFT;
fp = 63 - (fp | fpext << 2);
} else {
fp = env->fit_period[fp];
}
return fp;
}
/* Return the location of the bit of time base at which the WDT will raise an
interrupt */
static uint8_t booke_get_wdt_target(CPUPPCState *env, ppc_tb_t *tb_env)
{
uint8_t wp = (env->spr[SPR_BOOKE_TCR] & TCR_WP_MASK) >> TCR_WP_SHIFT;
if (tb_env->flags & PPC_TIMER_E500) {
/* e500 Watchdog timer period extension */
uint32_t wpext = (env->spr[SPR_BOOKE_TCR] & TCR_E500_WPEXT_MASK)
>> TCR_E500_WPEXT_SHIFT;
wp = 63 - (wp | wpext << 2);
} else {
wp = env->wdt_period[wp];
}
return wp;
}
static void booke_update_fixed_timer(CPUPPCState *env,
uint8_t target_bit,
uint64_t *next,
QEMUTimer *timer,
int tsr_bit)
{
ppc_tb_t *tb_env = env->tb_env;
uint64_t delta_tick, ticks = 0;
uint64_t tb;
uint64_t period;
uint64_t now;
if (!(env->spr[SPR_BOOKE_TSR] & tsr_bit)) {
/*
* Don't arm the timer again when the guest has the current
* interrupt still pending. Wait for it to ack it.
*/
return;
}
now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
tb = cpu_ppc_get_tb(tb_env, now, tb_env->tb_offset);
period = 1ULL << target_bit;
delta_tick = period - (tb & (period - 1));
/* the timer triggers only when the selected bit toggles from 0 to 1 */
if (tb & period) {
ticks = period;
}
if (ticks + delta_tick < ticks) {
/* Overflow, so assume the biggest number we can express. */
ticks = UINT64_MAX;
} else {
ticks += delta_tick;
}
*next = now + muldiv64(ticks, NANOSECONDS_PER_SECOND, tb_env->tb_freq);
if ((*next < now) || (*next > INT64_MAX)) {
/* Overflow, so assume the biggest number the qemu timer supports. */
*next = INT64_MAX;
}
/* XXX: If expire time is now. We can't run the callback because we don't
* have access to it. So we just set the timer one nanosecond later.
*/
if (*next == now) {
(*next)++;
} else {
/*
* There's no point to fake any granularity that's more fine grained
* than milliseconds. Anything beyond that just overloads the system.
*/
*next = MAX(*next, now + SCALE_MS);
}
/* Fire the next timer */
timer_mod(timer, *next);
}
static void booke_decr_cb(void *opaque)
{
PowerPCCPU *cpu = opaque;
CPUPPCState *env = &cpu->env;
env->spr[SPR_BOOKE_TSR] |= TSR_DIS;
booke_update_irq(cpu);
if (env->spr[SPR_BOOKE_TCR] & TCR_ARE) {
/* Do not reload 0, it is already there. It would just trigger
* the timer again and lead to infinite loop */
if (env->spr[SPR_BOOKE_DECAR] != 0) {
/* Auto Reload */
cpu_ppc_store_decr(env, env->spr[SPR_BOOKE_DECAR]);
}
}
}
static void booke_fit_cb(void *opaque)
{
PowerPCCPU *cpu = opaque;
CPUPPCState *env = &cpu->env;
ppc_tb_t *tb_env;
booke_timer_t *booke_timer;
tb_env = env->tb_env;
booke_timer = tb_env->opaque;
env->spr[SPR_BOOKE_TSR] |= TSR_FIS;
booke_update_irq(cpu);
booke_update_fixed_timer(env,
booke_get_fit_target(env, tb_env),
&booke_timer->fit_next,
booke_timer->fit_timer,
TSR_FIS);
}
static void booke_wdt_cb(void *opaque)
{
PowerPCCPU *cpu = opaque;
CPUPPCState *env = &cpu->env;
ppc_tb_t *tb_env;
booke_timer_t *booke_timer;
tb_env = env->tb_env;
booke_timer = tb_env->opaque;
/* TODO: There's lots of complicated stuff to do here */
booke_update_irq(cpu);
booke_update_fixed_timer(env,
booke_get_wdt_target(env, tb_env),
&booke_timer->wdt_next,
booke_timer->wdt_timer,
TSR_WIS);
}
void store_booke_tsr(CPUPPCState *env, target_ulong val)
{
PowerPCCPU *cpu = env_archcpu(env);
ppc_tb_t *tb_env = env->tb_env;
booke_timer_t *booke_timer = tb_env->opaque;
env->spr[SPR_BOOKE_TSR] &= ~val;
kvmppc_clear_tsr_bits(cpu, val);
if (val & TSR_FIS) {
booke_update_fixed_timer(env,
booke_get_fit_target(env, tb_env),
&booke_timer->fit_next,
booke_timer->fit_timer,
TSR_FIS);
}
if (val & TSR_WIS) {
booke_update_fixed_timer(env,
booke_get_wdt_target(env, tb_env),
&booke_timer->wdt_next,
booke_timer->wdt_timer,
TSR_WIS);
}
booke_update_irq(cpu);
}
void store_booke_tcr(CPUPPCState *env, target_ulong val)
{
PowerPCCPU *cpu = env_archcpu(env);
ppc_tb_t *tb_env = env->tb_env;
booke_timer_t *booke_timer = tb_env->opaque;
env->spr[SPR_BOOKE_TCR] = val;
kvmppc_set_tcr(cpu);
booke_update_irq(cpu);
booke_update_fixed_timer(env,
booke_get_fit_target(env, tb_env),
&booke_timer->fit_next,
booke_timer->fit_timer,
TSR_FIS);
booke_update_fixed_timer(env,
booke_get_wdt_target(env, tb_env),
&booke_timer->wdt_next,
booke_timer->wdt_timer,
TSR_WIS);
}
static void ppc_booke_timer_reset_handle(void *opaque)
{
PowerPCCPU *cpu = opaque;
CPUPPCState *env = &cpu->env;
store_booke_tcr(env, 0);
store_booke_tsr(env, -1);
}
/*
* This function will be called whenever the CPU state changes.
* CPU states are defined "typedef enum RunState".
* Regarding timer, When CPU state changes to running after debug halt
* or similar cases which takes time then in between final watchdog
* expiry happenes. This will cause exit to QEMU and configured watchdog
* action will be taken. To avoid this we always clear the watchdog state when
* state changes to running.
*/
static void cpu_state_change_handler(void *opaque, bool running, RunState state)
{
PowerPCCPU *cpu = opaque;
CPUPPCState *env = &cpu->env;
if (!running) {
return;
}
/*
* Clear watchdog interrupt condition by clearing TSR.
*/
store_booke_tsr(env, TSR_ENW | TSR_WIS | TSR_WRS_MASK);
}
void ppc_booke_timers_init(PowerPCCPU *cpu, uint32_t freq, uint32_t flags)
{
ppc_tb_t *tb_env;
booke_timer_t *booke_timer;
int ret = 0;
tb_env = g_malloc0(sizeof(ppc_tb_t));
booke_timer = g_malloc0(sizeof(booke_timer_t));
cpu->env.tb_env = tb_env;
tb_env->flags = flags | PPC_TIMER_BOOKE | PPC_DECR_ZERO_TRIGGERED;
tb_env->tb_freq = freq;
tb_env->decr_freq = freq;
tb_env->opaque = booke_timer;
tb_env->decr_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &booke_decr_cb, cpu);
booke_timer->fit_timer =
timer_new_ns(QEMU_CLOCK_VIRTUAL, &booke_fit_cb, cpu);
booke_timer->wdt_timer =
timer_new_ns(QEMU_CLOCK_VIRTUAL, &booke_wdt_cb, cpu);
ret = kvmppc_booke_watchdog_enable(cpu);
if (ret) {
/* TODO: Start the QEMU emulated watchdog if not running on KVM.
* Also start the QEMU emulated watchdog if KVM does not support
* emulated watchdog or somehow it is not enabled (supported but
* not enabled is though some bug and requires debugging :)).
*/
}
qemu_add_vm_change_state_handler(cpu_state_change_handler, cpu);
qemu_register_reset(ppc_booke_timer_reset_handle, cpu);
}
