[Qemu-devel] [PATCH] [PowerPC][RFC] booke timers

[Fabien Chouteau]

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).

This is a first attempt for a distinct and clean implementation of booke's
timers.

Please feel free to comment.

Signed-off-by: Fabien Chouteau <address@hidden>
---
 Makefile.target        |    2 +-
 hw/ppc.c               |   45 +--------
 hw/ppc.h               |   23 +++++
 hw/ppc_booke.c         |  254 ++++++++++++++++++++++++++++++++++++++++++++++++
 hw/ppce500_mpc8544ds.c |    4 +-
 5 files changed, 281 insertions(+), 47 deletions(-)
 create mode 100644 hw/ppc_booke.c

diff --git a/Makefile.target b/Makefile.target
index 38afdb8..f0d4062 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -242,7 +242,7 @@ obj-i386-$(CONFIG_KVM) += kvmclock.o
 obj-i386-$(CONFIG_SPICE) += qxl.o qxl-logger.o qxl-render.o
 
 # shared objects
-obj-ppc-y = ppc.o
+obj-ppc-y = ppc.o ppc_booke.o
 obj-ppc-y += vga.o
 # PREP target
 obj-ppc-y += i8259.o mc146818rtc.o
diff --git a/hw/ppc.c b/hw/ppc.c
index 9157719..9932136 100644
--- a/hw/ppc.c
+++ b/hw/ppc.c
@@ -50,7 +50,7 @@
 static void cpu_ppc_tb_stop (CPUState *env);
 static void cpu_ppc_tb_start (CPUState *env);
 
-static void ppc_set_irq (CPUState *env, int n_IRQ, int level)
+void ppc_set_irq (CPUState *env, int n_IRQ, int level)
 {
     unsigned int old_pending = env->pending_interrupts;
 
@@ -423,25 +423,8 @@ void ppce500_irq_init (CPUState *env)
 }
 /*****************************************************************************/
 /* PowerPC time base and decrementer emulation */
-struct ppc_tb_t {
-    /* Time base management */
-    int64_t  tb_offset;    /* Compensation                    */
-    int64_t  atb_offset;   /* Compensation                    */
-    uint32_t tb_freq;      /* TB frequency                    */
-    /* Decrementer management */
-    uint64_t decr_next;    /* Tick for next decr interrupt    */
-    uint32_t decr_freq;    /* decrementer frequency           */
-    struct QEMUTimer *decr_timer;
-    /* Hypervisor decrementer management */
-    uint64_t hdecr_next;    /* Tick for next hdecr interrupt  */
-    struct QEMUTimer *hdecr_timer;
-    uint64_t purr_load;
-    uint64_t purr_start;
-    void *opaque;
-};
 
-static inline uint64_t cpu_ppc_get_tb(ppc_tb_t *tb_env, uint64_t vmclk,
-                                      int64_t tb_offset)
+uint64_t cpu_ppc_get_tb(ppc_tb_t *tb_env, uint64_t vmclk, int64_t tb_offset)
 {
     /* TB time in tb periods */
     return muldiv64(vmclk, tb_env->tb_freq, get_ticks_per_sec()) + tb_offset;
@@ -996,30 +979,6 @@ target_ulong load_40x_pit (CPUState *env)
     return cpu_ppc_load_decr(env);
 }
 
-void store_booke_tsr (CPUState *env, target_ulong val)
-{
-    ppc_tb_t *tb_env = env->tb_env;
-    ppcemb_timer_t *ppcemb_timer;
-
-    ppcemb_timer = tb_env->opaque;
-
-    LOG_TB("%s: val " TARGET_FMT_lx "\n", __func__, val);
-    env->spr[SPR_40x_TSR] &= ~(val & 0xFC000000);
-    if (val & 0x80000000)
-        ppc_set_irq(env, ppcemb_timer->decr_excp, 0);
-}
-
-void store_booke_tcr (CPUState *env, target_ulong val)
-{
-    ppc_tb_t *tb_env;
-
-    tb_env = env->tb_env;
-    LOG_TB("%s: val " TARGET_FMT_lx "\n", __func__, val);
-    env->spr[SPR_40x_TCR] = val & 0xFFC00000;
-    start_stop_pit(env, tb_env, 1);
-    cpu_4xx_wdt_cb(env);
-}
-
 static void ppc_emb_set_tb_clk (void *opaque, uint32_t freq)
 {
     CPUState *env = opaque;
diff --git a/hw/ppc.h b/hw/ppc.h
index 3ccf134..633c53e 100644
--- a/hw/ppc.h
+++ b/hw/ppc.h
@@ -1,3 +1,5 @@
+void ppc_set_irq (CPUState *env, int n_IRQ, int level);
+
 /* PowerPC hardware exceptions management helpers */
 typedef void (*clk_setup_cb)(void *opaque, uint32_t freq);
 typedef struct clk_setup_t clk_setup_t;
@@ -11,6 +13,24 @@ static inline void clk_setup (clk_setup_t *clk, uint32_t 
freq)
         (*clk->cb)(clk->opaque, freq);
 }
 
+struct ppc_tb_t {
+    /* Time base management */
+    int64_t  tb_offset;    /* Compensation                    */
+    int64_t  atb_offset;   /* Compensation                    */
+    uint32_t tb_freq;      /* TB frequency                    */
+    /* Decrementer management */
+    uint64_t decr_next;    /* Tick for next decr interrupt    */
+    uint32_t decr_freq;    /* decrementer frequency           */
+    struct QEMUTimer *decr_timer;
+    /* Hypervisor decrementer management */
+    uint64_t hdecr_next;    /* Tick for next hdecr interrupt  */
+    struct QEMUTimer *hdecr_timer;
+    uint64_t purr_load;
+    uint64_t purr_start;
+    void *opaque;
+};
+
+uint64_t cpu_ppc_get_tb(ppc_tb_t *tb_env, uint64_t vmclk, int64_t tb_offset);
 clk_setup_cb cpu_ppc_tb_init (CPUState *env, uint32_t freq);
 /* Embedded PowerPC DCR management */
 typedef uint32_t (*dcr_read_cb)(void *opaque, int dcrn);
@@ -55,3 +75,6 @@ enum {
 #define FW_CFG_PPC_KVM_PID      (FW_CFG_ARCH_LOCAL + 0x07)
 
 #define PPC_SERIAL_MM_BAUDBASE 399193
+
+/* ppc_booke.c */
+void ppc_booke_timers_init (CPUState *env, uint32_t freq);
diff --git a/hw/ppc_booke.c b/hw/ppc_booke.c
new file mode 100644
index 0000000..71e13d2
--- /dev/null
+++ b/hw/ppc_booke.c
@@ -0,0 +1,254 @@
+/*
+ * 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_MASK   0x3       /* Watchdog Timer Period */
+#define TCR_WP_SHIFT  30
+#define TCR_WRC_MASK  0x3       /* Watchdog Timer Reset Control */
+#define TCR_WRC_SHIFT 28
+#define TCR_WIE       (1 << 27) /* Watchdog Timer Interrupt Enable */
+#define TCR_DIE       (1 << 26) /* Decrementer Interrupt Enable */
+#define TCR_FP_MASK   0x3       /* Fixed-Interval Timer Period */
+#define TCR_FP_SHIFT  24
+#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_MASK  0xf /* Fixed-Interval Timer Period Extension */
+#define TCR_E500_FPEXT_SHIFT 13
+#define TCR_E500_WPEXT_MASK  0xf /* Watchdog Timer Period Extension */
+#define TCR_E500_WPEXT_SHIFT 17
+
+/* Timer Status Register  */
+
+#define TSR_FIS       (1 << 26) /* Fixed-Interval Timer Interrupt Status */
+#define TSR_DIS       (1 << 27) /* Decrementer Interrupt Status */
+#define TSR_WRS_MASK  0x3       /* Watchdog Timer Reset Status */
+#define TSR_WRS_SHIFT 28
+#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 {
+    int decr_excp;
+
+    int fit_excp;
+    uint64_t fit_next;
+    struct QEMUTimer *fit_timer;
+
+    int wdt_excp;
+    uint64_t wdt_next;
+    struct QEMUTimer *wdt_timer;
+};
+
+/* Return the time base value at which the FIT will raise an interrupt */
+static uint64_t booke_get_fit_target(CPUState *env)
+{
+    uint32_t fp = (env->spr[SPR_BOOKE_TCR] >> TCR_FP_SHIFT) & TCR_FP_MASK;
+
+    /* Only for e500 */
+    if (env->insns_flags2 & PPC2_BOOKE206) {
+        uint32_t fpext = (env->spr[SPR_BOOKE_TCR] >> TCR_E500_FPEXT_SHIFT)
+            & TCR_E500_FPEXT_MASK;
+        fp |= fpext << 2;
+    }
+
+    return 1 << fp;
+}
+
+/* Return the time base value at which the WDT will raise an interrupt */
+static uint64_t booke_get_wdt_target(CPUState *env)
+{
+    uint32_t fp = (env->spr[SPR_BOOKE_TCR] >> TCR_WP_SHIFT) & TCR_WP_MASK;
+
+    /* Only for e500 */
+    if (env->insns_flags2 & PPC2_BOOKE206) {
+        uint32_t fpext = (env->spr[SPR_BOOKE_TCR] >> TCR_E500_WPEXT_SHIFT)
+            & TCR_E500_WPEXT_MASK;
+        fp |= fpext << 2;
+    }
+
+    return 1 << fp;
+}
+
+static void booke_update_fixed_timer(CPUState         *env,
+                                     uint64_t          tb_target,
+                                     uint64_t          *next,
+                                     struct QEMUTimer *timer)
+{
+    ppc_tb_t *tb_env = env->tb_env;
+    uint64_t lapse;
+    uint64_t tb;
+    uint64_t now;
+
+    now = qemu_get_clock_ns(vm_clock);
+    tb  = cpu_ppc_get_tb(tb_env, now, tb_env->tb_offset);
+
+    if (tb_target < tb) {
+        qemu_del_timer(timer);
+    } else {
+        lapse = tb_target - tb;
+        *next  = now + muldiv64(lapse, get_ticks_per_sec(), tb_env->tb_freq);
+
+        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;
+    if (env->spr[SPR_BOOKE_TCR] & TCR_DIE) {
+        ppc_set_irq(env, booke_timer->decr_excp, 1);
+    }
+
+    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;
+    if (env->spr[SPR_BOOKE_TCR] & TCR_FIE) {
+        ppc_set_irq(env, booke_timer->fit_excp, 1);
+    }
+
+    booke_update_fixed_timer(env,
+                             booke_get_fit_target(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 */
+    abort();
+
+    booke_update_fixed_timer(env,
+                             booke_get_wdt_target(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 & 0xFC000000);
+
+    if (val & TSR_DIS) {
+        ppc_set_irq(env, booke_timer->decr_excp, 0);
+    }
+
+    if (val & TSR_FIS) {
+        ppc_set_irq(env, booke_timer->fit_excp, 0);
+    }
+
+    if (val & TSR_WIS) {
+        ppc_set_irq(env, booke_timer->wdt_excp, 0);
+    }
+}
+
+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 & 0xFFC00000;
+
+    booke_update_fixed_timer(env,
+                             booke_get_fit_target(env),
+                             &booke_timer->fit_next,
+                             booke_timer->fit_timer);
+
+    booke_update_fixed_timer(env,
+                             booke_get_wdt_target(env),
+                             &booke_timer->wdt_next,
+                             booke_timer->wdt_timer);
+}
+
+void ppc_booke_timers_init (CPUState *env, uint32_t freq)
+{
+    ppc_tb_t *tb_env;
+    booke_timer_t *booke_timer;
+
+    tb_env      = qemu_mallocz(sizeof(ppc_tb_t));
+    booke_timer = qemu_mallocz(sizeof(booke_timer_t));
+
+    env->tb_env = tb_env;
+
+    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->decr_excp = PPC_INTERRUPT_DECR;
+    booke_timer->fit_excp = PPC_INTERRUPT_FIT;
+    booke_timer->wdt_excp = PPC_INTERRUPT_WDT;
+
+    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);
+}
diff --git a/hw/ppce500_mpc8544ds.c b/hw/ppce500_mpc8544ds.c
index 6b57fbf..83672c9 100644
--- a/hw/ppce500_mpc8544ds.c
+++ b/hw/ppce500_mpc8544ds.c
@@ -237,9 +237,7 @@ static void mpc8544ds_init(ram_addr_t ram_size,
         exit(1);
     }
 
-    /* XXX register timer? */
-    ppc_emb_timers_init(env, 400000000, PPC_INTERRUPT_DECR);
-    ppc_dcr_init(env, NULL, NULL);
+    ppc_booke_timers_init(env, 400000000);
 
     /* Register reset handler */
     qemu_register_reset(mpc8544ds_cpu_reset, env);
-- 
1.7.4.1