Gigabeat: Add timer functionality. Rework tick timer setup to be exactly 100Hz. Metronome should work now but some pcm changes are needed to have faster tocks work correctly (in the works).

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@13806 a1c6a512-1295-4272-9138-f99709370657

8 files changed, 265 insertions, 84 deletions

diff --git a/firmware/SOURCES b/firmware/SOURCES
index 644b7d7148..7e26ca0bc4 100644
--- a/firmware/SOURCES
+++ b/firmware/SOURCES
@@ -520,10 +520,12 @@ target/arm/s3c2440/gigabeat-fx/ata-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/backlight-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/button-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/i2c-meg-fx.c
+target/arm/s3c2440/gigabeat-fx/kernel-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/lcd-as-meg-fx.S
 target/arm/s3c2440/gigabeat-fx/lcd-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/power-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/sc606-meg-fx.c
+target/arm/s3c2440/gigabeat-fx/timer-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/usb-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/wmcodec-meg-fx.c
 target/arm/s3c2440/gigabeat-fx/dma_start.c
diff --git a/firmware/export/timer.h b/firmware/export/timer.h
index 35994ce5f2..63f0567165 100644
--- a/firmware/export/timer.h
+++ b/firmware/export/timer.h
@@ -25,7 +25,6 @@
 
 #ifndef SIMULATOR
 
-
 #if defined(CPU_PP)
  /* Portalplayer chips use a microsecond timer. */
  #define TIMER_FREQ 1000000
@@ -34,6 +33,8 @@
  #define TIMER_FREQ (CPU_FREQ/2)
 #elif CONFIG_CPU == PNX0101
  #define TIMER_FREQ 3000000
+#elif CONFIG_CPU == S3C2440
+ #include "timer-target.h"
 #else
  #define TIMER_FREQ CPU_FREQ
 #endif
@@ -46,5 +47,9 @@ void timers_adjust_prescale(int multiplier, bool enable_irq);
 #endif
 void timer_unregister(void);
 
+/* For target-specific interface use */
+extern void (*pfn_timer)(void);
+extern void (*pfn_unregister)(void);
+
 #endif /* !SIMULATOR */
 #endif /* __TIMER_H__ */
diff --git a/firmware/kernel.c b/firmware/kernel.c
index 2d4ccde267..b1a4e62a81 100644
--- a/firmware/kernel.c
+++ b/firmware/kernel.c
@@ -29,7 +29,7 @@
 volatile long current_tick NOCACHEDATA_ATTR = 0;
 #endif
 
-static void (*tick_funcs[MAX_NUM_TICK_TASKS])(void);
+void (*tick_funcs[MAX_NUM_TICK_TASKS])(void);
 
 /* This array holds all queues that are initiated. It is used for broadcast. */
 static struct event_queue *all_queues[32] NOCACHEBSS_ATTR;
@@ -708,40 +708,6 @@ void tick_start(unsigned int interval_in_ms)
 
     TIMER0.ctrl |= 0x80;  /* Enable the counter */
 }
-#elif CONFIG_CPU == S3C2440
-void tick_start(unsigned int interval_in_ms)
-{
-    TCON &= ~(1 << 20); // stop timer 4
-    // TODO: this constant depends on dividers settings inherited from
-    // firmware. Set them explicitly somwhere.
-    TCNTB4 = 12193 * interval_in_ms / 1000;
-    TCON |= 1 << 21; // set manual bit
-    TCON &= ~(1 << 21); // reset manual bit
-    TCON |= 1 << 22; //interval mode
-    TCON |= (1 << 20); // start timer 4
-
-    INTMOD &= ~(1 << 14); // timer 4 to IRQ mode
-    INTMSK &= ~(1 << 14); // timer 4 unmask interrupts
-}
-
-void TIMER4(void)
-{
-    int i;
-
-    SRCPND = TIMER4_MASK;
-    INTPND = TIMER4_MASK;
-
-    /* Run through the list of tick tasks */
-    for(i = 0; i < MAX_NUM_TICK_TASKS; i++)
-    {
-        if(tick_funcs[i])
-        {
-            tick_funcs[i]();
-        }
-    }
-
-    current_tick++;
-}
 #endif
 
 int tick_add_task(void (*f)(void))
diff --git a/firmware/target/arm/s3c2440/gigabeat-fx/kernel-meg-fx.c b/firmware/target/arm/s3c2440/gigabeat-fx/kernel-meg-fx.c
index 9df90a2344..39e4efab49 100644
--- a/firmware/target/arm/s3c2440/gigabeat-fx/kernel-meg-fx.c
+++ b/firmware/target/arm/s3c2440/gigabeat-fx/kernel-meg-fx.c
@@ -1,13 +1,49 @@
+#include "config.h"
+#include "system.h"
 #include "kernel.h"
+#include "timer.h"
 #include "thread.h"
 
-#include <stdio.h>
-#include "lcd.h"
-
 extern void (*tick_funcs[MAX_NUM_TICK_TASKS])(void);
 
-void timer4(void) {
-        int i;
+void tick_start(unsigned int interval_in_ms)
+{
+    /*
+     * Based on default PCLK of 49.1568MHz - scaling chosen to give
+     * remainder-free result for tick interval of 10ms (100Hz)
+     * Timer input clock frequency =
+     *      fPCLK / {prescaler value+1} / {divider value}
+     * TIMER_FREQ = 49156800 / 2
+     * 13300 = TIMER_FREQ / 231 / 8
+     * 49156800 = 19*(11)*(7)*7*5*5*(3)*2*2*2*2*2*2
+     * 231 = 11*7*3
+     */
+
+    /* stop timer 4 */
+    TCON &= ~(1 << 20);
+    /* Set the count for timer 4 */
+    TCNTB4 = (TIMER_FREQ / 231 / 8) * interval_in_ms / 1000;
+    /* Set the the prescaler value for timers 2,3, and 4 */
+    TCFG0 = (TCFG0 & ~0xff00) | ((231-1) << 8);
+    /* MUX4 = 1/16 */
+    TCFG1 = (TCFG1 & ~0xff0000) | 0x030000;
+    /* set manual bit */
+    TCON |= 1 << 21;
+    /* reset manual bit */
+    TCON &= ~(1 << 21);
+    /* interval mode */
+    TCON |= 1 << 22;
+    /* start timer 4 */
+    TCON |= (1 << 20);
+
+    /* timer 4 unmask interrupts */
+    INTMSK &= ~TIMER4_MASK;
+}
+
+void TIMER4(void)
+{
+    int i;
+
     /* Run through the list of tick tasks */
     for(i = 0; i < MAX_NUM_TICK_TASKS; i++)
     {
@@ -19,7 +55,6 @@ void timer4(void) {
 
     current_tick++;
 
-    /* following needs to be fixed.  */
-    /*wake_up_thread();*/
+    SRCPND = TIMER4_MASK;
+    INTPND = TIMER4_MASK;
 }
-
diff --git a/firmware/target/arm/s3c2440/gigabeat-fx/timer-meg-fx.c b/firmware/target/arm/s3c2440/gigabeat-fx/timer-meg-fx.c
new file mode 100644
index 0000000000..4654c7c845
--- /dev/null
+++ b/firmware/target/arm/s3c2440/gigabeat-fx/timer-meg-fx.c
@@ -0,0 +1,127 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Copyright (C) 2007 by Michael Sevakis
+*
+* All files in this archive are subject to the GNU General Public License.
+* See the file COPYING in the source tree root for full license agreement.
+*
+* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+* KIND, either express or implied.
+*
+****************************************************************************/
+#include "config.h"
+#include "cpu.h"
+#include "system.h"
+#include "timer.h"
+#include "logf.h"
+
+/* GPB0/TOUT0 should already have been configured as output so that pin
+   should not be a functional pin and TIMER0 output unseen there */
+void TIMER0(void)
+{
+    if (pfn_timer != NULL)
+        pfn_timer();
+
+    SRCPND = TIMER0_MASK;
+    INTPND = TIMER0_MASK;
+}
+
+static void stop_timer(void)
+{
+    /* mask interrupt */
+    INTMSK |= TIMER0_MASK;
+
+    /* stop any running TIMER0 */
+    TCON &= ~(1 << 0);
+
+    /* clear pending */
+    SRCPND = TIMER0_MASK;
+    INTPND = TIMER0_MASK;
+}
+
+bool __timer_set(long cycles, bool start)
+{
+    bool retval = false;
+
+    /* Find the minimum factor that puts the counter in range 1-65535 */
+    unsigned int prescaler = (cycles + 65534) / 65535;
+
+    /* Maximum divider setting is x / 256 / 16 = x / 4096 */
+    if (prescaler <= 4096)
+    {
+        int oldlevel;
+        unsigned int divider;
+
+        if (start && pfn_unregister != NULL)
+        {
+            pfn_unregister();
+            pfn_unregister = NULL;
+        }
+
+        oldlevel = set_irq_level(HIGHEST_IRQ_LEVEL);
+
+        TCMPB0 = 0;
+        TCNTB0 = (unsigned int)cycles / prescaler;
+
+        /* Max prescale is 255+1 */
+        for (divider = 0; prescaler > 256; prescaler >>= 1, divider++);
+
+        TCFG0 = (TCFG0 & ~0xff) | (prescaler - 1);
+        TCFG1 = (TCFG1 & ~0xf) | divider;
+
+        set_irq_level(oldlevel);
+
+        retval = true;
+    }
+
+    return retval;
+}
+
+bool __timer_register(void)
+{
+    bool retval = true;
+
+    int oldstatus = set_interrupt_status(IRQ_FIQ_DISABLED, IRQ_FIQ_STATUS);
+
+    stop_timer();
+
+    /* neurosis - make sure something didn't set GPB0 to TOUT0 */
+    if ((GPBCON & 0x3) != 0x2)
+    {
+        /* manual update: on (to reset count) */
+        TCON |= (1 << 1);
+        /* dead zone: off, inverter: off, manual off */
+        TCON &= ~((1 << 4) | (1 << 2) | (1 << 1));
+        /* interval mode (auto reload): on */
+        TCON |= (1 << 3);
+        /* start timer */
+        TCON |= (1 << 0);
+        /* unmask interrupt */
+        INTMSK &= ~TIMER0_MASK;
+    }
+
+    if (!(TCON & (1 << 0)))
+    {
+        /* timer could not be started due to config error */
+        logf("Timer error: GPB0 set to TOUT0");
+        retval = false;
+    }
+
+    set_interrupt_status(oldstatus, IRQ_FIQ_STATUS);
+
+    return retval;
+}
+
+void __timer_unregister(void)
+{
+    int oldstatus = set_interrupt_status(IRQ_FIQ_DISABLED, IRQ_FIQ_STATUS);
+    stop_timer();
+    set_interrupt_status(oldstatus, IRQ_FIQ_STATUS);
+}
diff --git a/firmware/target/arm/s3c2440/gigabeat-fx/timer-target.h b/firmware/target/arm/s3c2440/gigabeat-fx/timer-target.h
new file mode 100644
index 0000000000..e9f330cf8e
--- /dev/null
+++ b/firmware/target/arm/s3c2440/gigabeat-fx/timer-target.h
@@ -0,0 +1,39 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Copyright (C) 2007 by Michael Sevakis
+*
+* All files in this archive are subject to the GNU General Public License.
+* See the file COPYING in the source tree root for full license agreement.
+*
+* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+* KIND, either express or implied.
+*
+****************************************************************************/
+#ifndef TIMER_TARGET_H
+#define TIMER_TARGET_H
+
+/* timer is based on PCLK and minimum division is 2 */
+#define TIMER_FREQ (49156800/2)
+
+bool __timer_set(long cycles, bool set);
+bool __timer_register(void);
+void __timer_unregister(void);
+
+#define __TIMER_SET(cycles, set) \
+    __timer_set(cycles, set)
+
+#define __TIMER_REGISTER(reg_prio, unregister_callback, cycles, \
+                              int_prio, timer_callback) \
+    __timer_register()
+
+#define __TIMER_UNREGISTER(...) \
+    __timer_unregister()
+
+#endif /* TIMER_TARGET_H */
diff --git a/firmware/target/arm/system-arm.h b/firmware/target/arm/system-arm.h
index 99cab9e1a3..37c367fdc4 100644
--- a/firmware/target/arm/system-arm.h
+++ b/firmware/target/arm/system-arm.h
@@ -87,23 +87,6 @@ static inline uint32_t swap_odd_even32(uint32_t value)
     return value;
 }
 
-#define HIGHEST_IRQ_LEVEL (0x80)
-
-static inline int set_irq_level(int level)
-{
-    unsigned long cpsr;
-    int oldlevel;
-    /* Read the old level and set the new one */
-    asm volatile (
-        "mrs    %1, cpsr        \n"
-        "bic    %0, %1, #0x80   \n"
-        "orr    %0, %0, %2      \n"
-        "msr    cpsr_c, %0      \n"
-        : "=&r,r"(cpsr), "=&r,r"(oldlevel) : "r,i"(level & 0x80)
-    );
-    return oldlevel;
-}
-
 static inline void set_fiq_handler(void(*fiq_handler)(void))
 {
     /* Install the FIQ handler */
@@ -133,22 +116,35 @@ static inline void disable_fiq(void)
 }
 
 /* This one returns the old status */
-#define FIQ_ENABLED  0x00
-#define FIQ_DISABLED 0x40
-static inline int set_fiq_status(int status)
+#define IRQ_ENABLED      0x00
+#define IRQ_DISABLED     0x80
+#define IRQ_STATUS       0x80
+#define FIQ_ENABLED      0x00
+#define FIQ_DISABLED     0x40
+#define FIQ_STATUS       0x40
+#define IRQ_FIQ_ENABLED  0x00
+#define IRQ_FIQ_DISABLED 0xc0
+#define IRQ_FIQ_STATUS   0xc0
+#define HIGHEST_IRQ_LEVEL IRQ_DISABLED
+
+#define set_irq_level(status)  set_interrupt_status((status), IRQ_STATUS)
+#define set_fiq_status(status) set_interrupt_status((status), FIQ_STATUS)
+
+static inline int set_interrupt_status(int status, int mask)
 {
     unsigned long cpsr;
     int oldstatus;
-    /* Read the old level and set the new one */
+    /* Read the old levels and set the new ones */
     asm volatile (
         "mrs    %1, cpsr        \n"
-        "bic    %0, %1, #0x40   \n"
+        "bic    %0, %1, %[mask] \n"
         "orr    %0, %0, %2      \n"
         "msr    cpsr_c, %0      \n"
-        : "=&r,r"(cpsr), "=&r,r"(oldstatus) : "r,i"(status & 0x40)
+        : "=&r,r"(cpsr), "=&r,r"(oldstatus)
+        : "r,i"(status & mask), [mask]"i,i"(mask)
     );
+
     return oldstatus;
 }
 
-
 #endif /* SYSTEM_ARM_H */
diff --git a/firmware/timer.c b/firmware/timer.c
index ca23cb890c..1ac16b697a 100644
--- a/firmware/timer.c
+++ b/firmware/timer.c
@@ -22,10 +22,11 @@
 #include "cpu.h"
 #include "system.h"
 #include "timer.h"
+#include "logf.h"
 
 static int timer_prio = -1;
-static void (*pfn_timer)(void) = NULL;      /* timer callback */
-static void (*pfn_unregister)(void) = NULL; /* unregister callback */
+void (*pfn_timer)(void) = NULL;      /* timer callback */
+void (*pfn_unregister)(void) = NULL; /* unregister callback */
 #ifdef CPU_COLDFIRE
 static int base_prescale;
 #elif defined CPU_PP || CONFIG_CPU == PNX0101
@@ -123,9 +124,9 @@ static bool timer_set(long cycles, bool start)
     }
     else
         cycles_new = cycles;
-#endif
 
-#if CONFIG_CPU == SH7034
+    return true;
+#elif CONFIG_CPU == SH7034
     if (prescale > 8)
         return false;
 
@@ -150,6 +151,7 @@ static bool timer_set(long cycles, bool start)
         TCNT4 = 0;
     and_b(~0x01, &TSR4); /* clear an eventual interrupt */
 
+    return true;
 #elif defined CPU_COLDFIRE
     if (prescale > 4096/CPUFREQ_MAX_MULT)
         return false;
@@ -186,6 +188,8 @@ static bool timer_set(long cycles, bool start)
     if (start || (TCN1 >= TRR1))
         TCN1 = 0; /* reset the timer */
     TER1 = 0xff;  /* clear all events */
+
+    return true;
 #elif defined(CPU_PP)
     if (cycles > 0x20000000 || cycles < 2)
         return false;
@@ -203,11 +207,10 @@ static bool timer_set(long cycles, bool start)
     else
         cycles_new = cycles;
 
-#elif CONFIG_CPU == S3C2440  /* TODO: Implement for the Gigabeat */
-    (void)start;
-    (void)cycles;
-#endif /* CONFIG_CPU */
     return true;
+#elif CONFIG_CPU == S3C2440
+    return __TIMER_SET(cycles, start);
+#endif /* CONFIG_CPU */
 }
 
 #ifdef CPU_COLDFIRE
@@ -236,16 +239,9 @@ bool timer_register(int reg_prio, void (*unregister_callback)(void),
     if (reg_prio <= timer_prio || cycles == 0)
         return false;
 
-#if defined(CPU_PP) || (CONFIG_CPU==PNX0101) || (CONFIG_CPU==S3C2440)
-    /* TODO: Implement for PortalPlayer and iFP (if possible) */
-    (void)int_prio;
-#endif
-
 #if CONFIG_CPU == SH7034
     if (int_prio < 1 || int_prio > 15)
         return false;
-#elif defined CPU_COLDFIRE
-    (void)int_prio;
 #endif
 
     if (!timer_set(cycles, true))
@@ -258,18 +254,31 @@ bool timer_register(int reg_prio, void (*unregister_callback)(void),
 #if CONFIG_CPU == SH7034
     IPRD = (IPRD & 0xFF0F) | int_prio << 4;  /* interrupt priority */
     or_b(0x10, &TSTR); /* start timer 4 */
+    return true;
 #elif defined CPU_COLDFIRE
     ICR2 = 0x90;       /* interrupt on level 4.0 */
     and_l(~(1<<10), &IMR);
     TMR1 |= 1;         /* start timer */
+    return true;
 #elif defined(CPU_PP)
     /* unmask interrupt source */
     CPU_INT_EN = TIMER2_MASK;
+    return true;
 #elif CONFIG_CPU == PNX0101
     irq_set_int_handler(IRQ_TIMER1, TIMER1_ISR);
     irq_enable_int(IRQ_TIMER1);
-#endif
     return true;
+#elif CONFIG_CPU == S3C2440
+    return __TIMER_REGISTER(reg_prio, unregister_callback, cycles,
+                            int_prio, timer_callback);
+#endif
+    /* Cover for targets that don't use all these */
+    (void)reg_prio;
+    (void)unregister_callback;
+    (void)cycles;
+    /* TODO: Implement for PortalPlayer and iFP (if possible) */
+    (void)int_prio;
+    (void)timer_callback; 
 }
 
 bool timer_set_period(long cycles)
@@ -291,6 +300,8 @@ void timer_unregister(void)
 #elif CONFIG_CPU == PNX0101
     TIMER1.ctrl &= ~0x80;  /* disable timer 1 */
     irq_disable_int(5);
+#elif CONFIG_CPU == S3C2440
+    __TIMER_UNREGISTER();
 #endif
     pfn_timer = NULL;
     pfn_unregister = NULL;