PPC: booke timers

While working on the emulation of the freescale p2010 (e500v2) I realized that
there's no implementation of booke's timers features. Currently mpc8544 uses
ppc_emb (ppc_emb_timers_init) which is close but not exactly like booke (for
example booke uses different SPR).

Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/hw/ppc_booke.c b/hw/ppc_booke.c
new file mode 100644
index 0000000..3e2fff5
--- /dev/null
+++ b/hw/ppc_booke.c
@@ -0,0 +1,266 @@
+/*
+ * 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 "hw.h"
+#include "ppc.h"
+#include "qemu-timer.h"
+#include "sysemu.h"
+#include "nvram.h"
+#include "qemu-log.h"
+#include "loader.h"
+
+
+/* Timer Control Register */
+
+#define TCR_WP_SHIFT  30        /* Watchdog Timer Period */
+#define TCR_WP_MASK   (0x3 << TCR_WP_SHIFT)
+#define TCR_WRC_SHIFT 28        /* Watchdog Timer Reset Control */
+#define TCR_WRC_MASK  (0x3 << TCR_WRC_SHIFT)
+#define TCR_WIE       (1 << 27) /* Watchdog Timer Interrupt Enable */
+#define TCR_DIE       (1 << 26) /* Decrementer Interrupt Enable */
+#define TCR_FP_SHIFT  24        /* Fixed-Interval Timer Period */
+#define TCR_FP_MASK   (0x3 << TCR_FP_SHIFT)
+#define TCR_FIE       (1 << 23) /* Fixed-Interval Timer Interrupt Enable */
+#define TCR_ARE       (1 << 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       (1 << 26) /* Fixed-Interval Timer Interrupt Status */
+#define TSR_DIS       (1 << 27) /* Decrementer Interrupt Status */
+#define TSR_WRS_SHIFT 28        /* Watchdog Timer Reset Status */
+#define TSR_WRS_MASK  (0x3 << TSR_WRS_SHIFT)
+#define TSR_WIS       (1 << 30) /* Watchdog Timer Interrupt Status */
+#define TSR_ENW       (1 << 31) /* Enable Next Watchdog Timer */
+
+typedef struct booke_timer_t booke_timer_t;
+struct booke_timer_t {
+
+    uint64_t fit_next;
+    struct QEMUTimer *fit_timer;
+
+    uint64_t wdt_next;
+    struct QEMUTimer *wdt_timer;
+
+    uint32_t flags;
+};
+
+static void booke_update_irq(CPUState *env)
+{
+    ppc_set_irq(env, PPC_INTERRUPT_DECR,
+                (env->spr[SPR_BOOKE_TSR] & TSR_DIS
+                 && env->spr[SPR_BOOKE_TCR] & TCR_DIE));
+
+    ppc_set_irq(env, PPC_INTERRUPT_WDT,
+                (env->spr[SPR_BOOKE_TSR] & TSR_WIS
+                 && env->spr[SPR_BOOKE_TCR] & TCR_WIE));
+
+    ppc_set_irq(env, 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(CPUState *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(CPUState *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(CPUState         *env,
+                                     uint8_t           target_bit,
+                                     uint64_t          *next,
+                                     struct QEMUTimer *timer)
+{
+    ppc_tb_t *tb_env = env->tb_env;
+    uint64_t lapse;
+    uint64_t tb;
+    uint64_t period = 1 << (target_bit + 1);
+    uint64_t now;
+
+    now = qemu_get_clock_ns(vm_clock);
+    tb  = cpu_ppc_get_tb(tb_env, now, tb_env->tb_offset);
+
+    lapse = period - ((tb - (1 << target_bit)) & (period - 1));
+
+    *next = now + muldiv64(lapse, get_ticks_per_sec(), tb_env->tb_freq);
+
+    /* 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)++;
+    }
+
+    qemu_mod_timer(timer, *next);
+}
+
+static void booke_decr_cb(void *opaque)
+{
+    CPUState *env;
+    ppc_tb_t *tb_env;
+    booke_timer_t *booke_timer;
+
+    env = opaque;
+    tb_env = env->tb_env;
+    booke_timer = tb_env->opaque;
+    env->spr[SPR_BOOKE_TSR] |= TSR_DIS;
+
+    booke_update_irq(env);
+
+    if (env->spr[SPR_BOOKE_TCR] & TCR_ARE) {
+        /* Auto Reload */
+        cpu_ppc_store_decr(env, env->spr[SPR_BOOKE_DECAR]);
+    }
+}
+
+static void booke_fit_cb(void *opaque)
+{
+    CPUState *env;
+    ppc_tb_t *tb_env;
+    booke_timer_t *booke_timer;
+
+    env = opaque;
+    tb_env = env->tb_env;
+    booke_timer = tb_env->opaque;
+    env->spr[SPR_BOOKE_TSR] |= TSR_FIS;
+
+    booke_update_irq(env);
+
+    booke_update_fixed_timer(env,
+                             booke_get_fit_target(env, tb_env),
+                             &booke_timer->fit_next,
+                             booke_timer->fit_timer);
+}
+
+static void booke_wdt_cb(void *opaque)
+{
+    CPUState *env;
+    ppc_tb_t *tb_env;
+    booke_timer_t *booke_timer;
+
+    env = opaque;
+    tb_env = env->tb_env;
+    booke_timer = tb_env->opaque;
+
+    /* TODO: There's lots of complicated stuff to do here */
+
+    booke_update_irq(env);
+
+    booke_update_fixed_timer(env,
+                             booke_get_wdt_target(env, tb_env),
+                             &booke_timer->wdt_next,
+                             booke_timer->wdt_timer);
+}
+
+void store_booke_tsr(CPUState *env, target_ulong val)
+{
+    ppc_tb_t *tb_env = env->tb_env;
+    booke_timer_t *booke_timer;
+
+    booke_timer = tb_env->opaque;
+
+    env->spr[SPR_BOOKE_TSR] &= ~val;
+
+    booke_update_irq(env);
+}
+
+void store_booke_tcr(CPUState *env, target_ulong val)
+{
+    ppc_tb_t *tb_env = env->tb_env;
+    booke_timer_t *booke_timer = tb_env->opaque;
+
+    tb_env = env->tb_env;
+    env->spr[SPR_BOOKE_TCR] = val;
+
+    booke_update_irq(env);
+
+    booke_update_fixed_timer(env,
+                             booke_get_fit_target(env, tb_env),
+                             &booke_timer->fit_next,
+                             booke_timer->fit_timer);
+
+    booke_update_fixed_timer(env,
+                             booke_get_wdt_target(env, tb_env),
+                             &booke_timer->wdt_next,
+                             booke_timer->wdt_timer);
+
+}
+
+void ppc_booke_timers_init(CPUState *env, uint32_t freq, uint32_t flags)
+{
+    ppc_tb_t *tb_env;
+    booke_timer_t *booke_timer;
+
+    tb_env      = g_malloc0(sizeof(ppc_tb_t));
+    booke_timer = g_malloc0(sizeof(booke_timer_t));
+
+    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 = qemu_new_timer_ns(vm_clock, &booke_decr_cb, env);
+
+    booke_timer->fit_timer =
+        qemu_new_timer_ns(vm_clock, &booke_fit_cb, env);
+    booke_timer->wdt_timer =
+        qemu_new_timer_ns(vm_clock, &booke_wdt_cb, env);
+}