FS#10245 by Jack Halpin : Adjust Clocking scheme on Sansa AMS

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21088 a1c6a512-1295-4272-9138-f99709370657

9 files changed, 155 insertions, 73 deletions

diff --git a/firmware/target/arm/as3525/ascodec-as3525.c b/firmware/target/arm/as3525/ascodec-as3525.c
index b9790217aa..668c001f9b 100644
--- a/firmware/target/arm/as3525/ascodec-as3525.c
+++ b/firmware/target/arm/as3525/ascodec-as3525.c
@@ -78,7 +78,7 @@ void ascodec_init(void)
     CGU_PERI |= CGU_I2C_AUDIO_MASTER_CLOCK_ENABLE;
 
     /* prescaler for i2c clock */
-    prescaler = CLK_DIV(AS3525_PCLK_FREQ, AS3525_I2C_FREQ);
+    prescaler = AS3525_I2C_PRESCALER;
     I2C2_CPSR0 = prescaler & 0xFF;          /* 8 lsb */
     I2C2_CPSR1 = (prescaler >> 8) & 0x3;    /* 2 msb */
     
diff --git a/firmware/target/arm/as3525/ata_sd_as3525.c b/firmware/target/arm/as3525/ata_sd_as3525.c
index 6d6b275fba..03a6a8bd02 100644
--- a/firmware/target/arm/as3525/ata_sd_as3525.c
+++ b/firmware/target/arm/as3525/ata_sd_as3525.c
@@ -456,8 +456,7 @@ static void init_pl180_controller(const int drive)
 
     MCI_SELECT(drive) = 0;
 
-    MCI_CLOCK(drive) = MCI_CLOCK_ENABLE |
-                (((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SD_IDENT_FREQ)) / 2) - 1);
+    MCI_CLOCK(drive) = MCI_CLOCK_ENABLE | AS3525_SD_IDENT_DIV;
     mci_delay();
 }
 
@@ -466,8 +465,8 @@ int sd_init(void)
     int ret;
     CGU_IDE =   (1<<7)  /* AHB interface enable */  |
                 (1<<6)  /* interface enable */      |
-                ((CLK_DIV(AS3525_PLLA_FREQ, AS3525_IDE_FREQ) - 1) << 2) |
-                1;       /* clock source = PLLA */
+                (AS3525_IDE_DIV << 2)               |
+                AS3525_CLK_PLLA;  /* clock source = PLLA */
 
 
     CGU_PERI |= CGU_NAF_CLOCK_ENABLE;
diff --git a/firmware/target/arm/as3525/clock-target.h b/firmware/target/arm/as3525/clock-target.h
index 1928f1fbf2..a6e4927386 100644
--- a/firmware/target/arm/as3525/clock-target.h
+++ b/firmware/target/arm/as3525/clock-target.h
@@ -24,47 +24,120 @@
 /* returns clock divider, given maximal target frequency and clock reference */
 #define CLK_DIV(ref, target) ((ref + target - 1) / target)
 
-/* PLL */
 
-#define AS3525_PLLA_FREQ        248000000
+/*  Frequency and Bus Settings
+ *  These bus settings work on the assumption that unboosted performance will be
+ *  based on fastbus mode(FCLK == PCLK) at a frequency configured with this file.
+ *  Boosted performance defaults to synchronous bus but will be changed to
+ *  asynchronous bus if FCLK is not an integer multiple of PCLK.
+ *  The player starts up in fastbus mode and synchronous or asynchronous mode is
+ *  implemented in the set_cpu_frequency() function in system-as3525.c.  There
+ *  are limitations on both frequencies and frequency relationships listed in 7.3.14
+ *  of the as3525 datasheet that need to be observed.  If you are determined to
+ *  use a frequency that is not "legal" you can do that. There are no checks for
+ *  legal frequency values, only some validity checks to make sure the divider
+ *  value fits into the number of bits allotted to it.
+ *
+ *  The CLOCK_DIV macro does a pretty good job at selecting divider values but
+ *  you can always overide it by choosing your own value and commenting out the
+ *  macro.  If you are going to use AS3525_FCLK_PREDIV or AS3525_PCLK_DIV1 you
+ *  will have to do a manual calculation.  I have included USB & PLLB for future
+ *  use but commented them out for now.
+ */
+
+/* Clock Sources  */
+#define AS3525_CLK_MAIN           0
+#define AS3525_CLK_PLLA           1
+//#define AS3525_CLK_PLLB           2
+#define AS3525_CLK_FCLK           3         /* for synchronous bus only  */
+
+/* PLL  frequencies and settings*/
+
+#define AS3525_PLLA_FREQ        248000000   /*124,82.7,62,49.6,41.3,35.4 */
+       /* FCLK_PREDIV->  *7/8 = 217MHz      108.5 ,72.3, 54.25, 43.4, 36.17 */
+                      /* *6/8 = 186MHz      93, 62, 46.5, 37.2 */
+                      /* *5/8 = 155MHz      77.5, 51.67, 38.75 */
 #define AS3525_PLLA_SETTING     0x261F
 
-/* CPU */
+//#define AS3525_PLLA_FREQ        384000000 /*192,128,96,76.8,64,54.9,48,42.7,38.4*/
+       /* FCLK_PREDIV->  *7/8 = 336MHz      168, 112, 84, 67.2, 56, 48, 42, 37.3*/
+                      /* *6/8 = 288MHz      144, 96, 72, 57.6, 48, 41.1, */
+                      /* *5/8 = 240MHz      120, 80, 60, 48, 40  */
+//#define AS3525_PLLA_SETTING     0x2630
 
-/* ensure that PLLA_FREQ * prediv == CPUFREQ_MAX */
-#define AS3525_CPU_PREDIV       0 /* div = 1/1 */
+/*  PLLB not used at this time! */
+//#define AS3525_PLLB_FREQ
+//#define AS3525_PLLB_SETTING
 
-#define CPUFREQ_MAX             248000000
+/** ************ Change these to reconfigure clocking scheme *******************/
 
-#define CPUFREQ_DEFAULT         24800000
+#define AS3525_FCLK_FREQ         248000000          /* Boosted FCLK frequency  */
+#define AS3525_PCLK_FREQ         62000000           /* Initial PCLK frequency  */
+#define AS3525_DBOP_FREQ         AS3525_PCLK_FREQ   /* Initial DBOP frequency  */
 
-#define CPUFREQ_NORMAL          31000000
+/** ****************************************************************************/
 
-/* peripherals */
+/* Figure out if we need to use asynchronous bus */
+#if (AS3525_FCLK_FREQ % AS3525_PCLK_FREQ)
+#define ASYNCHRONOUS_BUS                          /* Boosted mode asynchronous */
+#endif
 
-#define AS3525_PCLK_FREQ        62000000
-#if (CLK_DIV(AS3525_PLLA_FREQ, AS3525_PCLK_FREQ) - 1) >= (1<<4) /* 4 bits */
-#error PCLK frequency is too low : clock divider will not fit !
+/* Tell the software what frequencies we're running */
+#define CPUFREQ_MAX              AS3525_FCLK_FREQ
+#define CPUFREQ_DEFAULT          AS3525_PCLK_FREQ
+#define CPUFREQ_NORMAL           AS3525_PCLK_FREQ
+
+/* FCLK */
+#define AS3525_FCLK_SEL          AS3525_CLK_PLLA
+#define AS3525_FCLK_PREDIV       0   /* div = (8-n)/8 acts strange when used!*/
+#define AS3525_FCLK_POSTDIV      (CLK_DIV(AS3525_PLLA_FREQ, AS3525_FCLK_FREQ) - 1) /*div=1/(n+1)*/
+
+/* PCLK */
+#ifdef ASYNCHRONOUS_BUS
+#define AS3525_PCLK_SEL          AS3525_CLK_PLLA    /* PLLA input for asynchronous */
+#define AS3525_PCLK_DIV0         (CLK_DIV(AS3525_PLLA_FREQ, AS3525_PCLK_FREQ) - 1)/*div=1/(n+1)*/
+#else
+#define AS3525_PCLK_SEL          AS3525_CLK_FCLK    /* Fclk input for synchronous */
+#define AS3525_PCLK_DIV0         (CLK_DIV(AS3525_FCLK_FREQ, AS3525_PCLK_FREQ) - 1) /*div=1/(n+1)*/
 #endif
+#define AS3525_PCLK_DIV1         0 /* div = 1/(n+1) unable to use successfuly so far*/
+
+   /* PCLK as Source */
+  #define AS3525_DBOP_DIV        (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1) /*div=1/(n+1)*/
+  #define AS3525_I2C_PRESCALER   CLK_DIV(AS3525_PCLK_FREQ, AS3525_I2C_FREQ)
+  #define AS3525_I2C_FREQ        400000
+  #define AS3525_SD_IDENT_DIV    ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SD_IDENT_FREQ) / 2) - 1)
+  #define AS3525_SD_IDENT_FREQ   400000      /* must be between 100 & 400 kHz */
 
-#define AS3525_IDE_FREQ         90000000    /* The OF uses 66MHz maximal freq
+#define AS3525_IDE_SEL           AS3525_CLK_PLLA           /* Input Source   */
+#define AS3525_IDE_DIV           (CLK_DIV(AS3525_PLLA_FREQ, AS3525_IDE_FREQ) - 1)/*div=1/(n+1)*/
+#define AS3525_IDE_FREQ          90000000    /* The OF uses 66MHz maximal freq
                                                but sd transfers fail on some
                                                players with this limit */
+
+//#define AS3525_USB_SEL           AS3525_CLK_PLLA            /* Input Source   */
+//#define AS3525_USB_DIV           /* div = 1/(n=0?1:2n)*/
+
+
+/* Validity Checks */
+
+/* AS3525_PCLK_FREQ  */
+#if (CLK_DIV(AS3525_PLLA_FREQ, AS3525_PCLK_FREQ) - 1) >= (1<<4) /* 4 bits */
+#error PCLK frequency is too low : clock divider will not fit !
+#endif
+/*  AS3525_DBOP_FREQ */
+#if (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1) >= (1<<3) /* 3 bits */
+#error DBOP frequency is too low : clock divider will not fit !
+#endif
+/* AS3525_IDE_FREQ */
 #if (CLK_DIV(AS3525_PLLA_FREQ, AS3525_IDE_FREQ) - 1) >= (1<<4) /* 4 bits */
 #error IDE frequency is too low : clock divider will not fit !
 #endif
-
-#define AS3525_I2C_FREQ         400000
+/* AS3525_I2C_FREQ */
 #if (CLK_DIV(AS3525_PCLK_FREQ, AS3525_I2C_FREQ)) >= (1<<10) /* 2+8 bits */
 #error I2C frequency is too low : clock divider will not fit !
 #endif
-
-#define AS3525_DBOP_FREQ        32000000
-#if (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1) >= (1<<3) /* 3 bits */
-#error DBOP frequency is too low : clock divider will not fit !
-#endif
-
-#define AS3525_SD_IDENT_FREQ    400000      /* must be between 100 & 400 kHz */
+/* AS3525_SD_IDENT_FREQ */
 #if ((CLK_DIV(AS3525_PCLK_FREQ, AS3525_SD_IDENT_FREQ) / 2) - 1) >= (1<<8) /* 8 bits */
 #error SD IDENTIFICATION frequency is too low : clock divider will not fit !
 #endif
diff --git a/firmware/target/arm/as3525/debug-as3525.c b/firmware/target/arm/as3525/debug-as3525.c
index ac7253d579..ea1bf9c381 100644
--- a/firmware/target/arm/as3525/debug-as3525.c
+++ b/firmware/target/arm/as3525/debug-as3525.c
@@ -120,39 +120,39 @@ int calc_freq(int clk)
             switch(CGU_PROC & 3) {
                 case 0:
                     return CLK_MAIN/
-                    ((8/(8-((CGU_PROC & 0xc)>>2)))*(((CGU_PROC & 0xf0)>>4) + 1));
+                    ((8/(8-((CGU_PROC>>2)& 0x3)))*(((CGU_PROC>>4)& 0xf) + 1));
                 case 1:
                     return calc_freq(CLK_PLLA)/
-                    ((8/(8-((CGU_PROC & 0xc)>>2)))*(((CGU_PROC & 0xf0)>>4) + 1));
+                    ((8/(8-((CGU_PROC>>2)& 0x3)))*(((CGU_PROC>>4)& 0xf) + 1));
                 case 2:
                     return calc_freq(CLK_PLLB)/
-                    ((8/(8-((CGU_PROC & 0xc)>>2)))*(((CGU_PROC & 0xf0)>>4) + 1));
+                    ((8/(8-((CGU_PROC>>2)& 0x3)))*(((CGU_PROC>>4)& 0xf) + 1));
                 default:
                     return 0;
             }
         case CLK_EXTMEM:
             switch(CGU_PERI & 3) {
                 case 0:
-                    return CLK_MAIN/(((CGU_PERI & 0x3c)>>2)+1);
+                    return CLK_MAIN/(((CGU_PERI>>2)& 0xf)+1);
                 case 1:
-                    return calc_freq(CLK_PLLA)/(((CGU_PERI & 0x3c)>>2)+1);
+                    return calc_freq(CLK_PLLA)/(((CGU_PERI>>2)& 0xf)+1);
                 case 2:
-                    return calc_freq(CLK_PLLB)/(((CGU_PERI & 0x3c)>>2)+1);
+                    return calc_freq(CLK_PLLB)/(((CGU_PERI>>2)& 0xf)+1);
                 case 3:
-                    return calc_freq(CLK_FCLK)/(((CGU_PERI & 0x3c)>>2)+1);
+                    return calc_freq(CLK_FCLK)/(((CGU_PERI>>2)& 0xf)+1);
                 default:
                     return 0;
             }
         case CLK_PCLK:
-            return calc_freq(CLK_EXTMEM)/(((CGU_PERI & 0x40)>>6)+1);
+            return calc_freq(CLK_EXTMEM)/(((CGU_PERI>>6)& 0x1)+1);
         case CLK_IDE:
             switch(CGU_IDE & 3) {
                 case 0:
-                    return CLK_MAIN/(((CGU_IDE & 0x3c)>>2)+1);
+                    return CLK_MAIN/(((CGU_IDE>>2)& 0xf)+1);
                 case 1:
-                    return calc_freq(CLK_PLLA)/(((CGU_IDE & 0x3c)>>2)+1);;
+                    return calc_freq(CLK_PLLA)/(((CGU_IDE>>2)& 0xf)+1);
                 case 2:
-                    return calc_freq(CLK_PLLB)/(((CGU_IDE & 0x3c)>>2)+1);
+                    return calc_freq(CLK_PLLB)/(((CGU_IDE>>2)& 0xf)+1);
                 default:
                     return 0;
             }
diff --git a/firmware/target/arm/as3525/sansa-c200v2/lcd-c200v2.c b/firmware/target/arm/as3525/sansa-c200v2/lcd-c200v2.c
index 0ffe0bdc8d..e16b082ce5 100644
--- a/firmware/target/arm/as3525/sansa-c200v2/lcd-c200v2.c
+++ b/firmware/target/arm/as3525/sansa-c200v2/lcd-c200v2.c
@@ -98,7 +98,7 @@ static void lcd_delay(int x)
 /* DBOP initialisation, do what OF does */
 static void ams3525_dbop_init(void)
 {
-    CGU_DBOP = (1<<3) | (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1);
+    CGU_DBOP = (1<<3) | AS3525_DBOP_DIV;
 
     DBOP_TIMPOL_01 = 0xe167e167;
     DBOP_TIMPOL_23 = 0xe167006e;
diff --git a/firmware/target/arm/as3525/sansa-clip/lcd-ssd1303.c b/firmware/target/arm/as3525/sansa-clip/lcd-ssd1303.c
index 70db6a3f0e..c0df1f766e 100644
--- a/firmware/target/arm/as3525/sansa-clip/lcd-ssd1303.c
+++ b/firmware/target/arm/as3525/sansa-clip/lcd-ssd1303.c
@@ -70,7 +70,7 @@
 /* DBOP initialisation, do what OF does */
 static void ams3525_dbop_init(void)
 {
-    CGU_DBOP = (1<<3) | (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1);
+    CGU_DBOP = (1<<3) | AS3525_DBOP_DIV;
 
     GPIOB_AFSEL = 0x08; /* DBOP on pin 3 */
     GPIOC_AFSEL = 0x0f; /* DBOP on pins 3:0 */
diff --git a/firmware/target/arm/as3525/sansa-e200v2/lcd-e200v2.c b/firmware/target/arm/as3525/sansa-e200v2/lcd-e200v2.c
index 9e23dac340..2958298b73 100644
--- a/firmware/target/arm/as3525/sansa-e200v2/lcd-e200v2.c
+++ b/firmware/target/arm/as3525/sansa-e200v2/lcd-e200v2.c
@@ -108,7 +108,7 @@ static void lcd_delay(int x)
 /* DBOP initialisation, do what OF does */
 static void ams3525_dbop_init(void)
 {
-    CGU_DBOP = (1<<3) | (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1);
+    CGU_DBOP = (1<<3) | AS3525_DBOP_DIV;
 
     DBOP_TIMPOL_01 = 0xe167e167;
     DBOP_TIMPOL_23 = 0xe167006e;
diff --git a/firmware/target/arm/as3525/sansa-fuze/lcd-fuze.c b/firmware/target/arm/as3525/sansa-fuze/lcd-fuze.c
index f0c85f53b4..f713425b9a 100644
--- a/firmware/target/arm/as3525/sansa-fuze/lcd-fuze.c
+++ b/firmware/target/arm/as3525/sansa-fuze/lcd-fuze.c
@@ -50,7 +50,7 @@ static bool lcd_busy = false;
 
 static void as3525_dbop_init(void)
 {
-    CGU_DBOP = (1<<3) | (CLK_DIV(AS3525_PCLK_FREQ, AS3525_DBOP_FREQ) - 1);
+    CGU_DBOP = (1<<3) | AS3525_DBOP_DIV;
 
     DBOP_TIMPOL_01 = 0xe167e167;
     DBOP_TIMPOL_23 = 0xe167006e;
diff --git a/firmware/target/arm/as3525/system-as3525.c b/firmware/target/arm/as3525/system-as3525.c
index a5f34d9b80..2f320e91ab 100644
--- a/firmware/target/arm/as3525/system-as3525.c
+++ b/firmware/target/arm/as3525/system-as3525.c
@@ -229,29 +229,25 @@ void system_init(void)
     CGU_PROC = 0;           /* fclk 24 MHz */
     CGU_PERI &= ~0x7f;      /* pclk 24 MHz */
 
-    asm volatile(
-        "mrc p15, 0, r0, c1, c0  \n"
-        "orr r0, r0, #0xC0000000 \n" /* asynchronous clocking */
-        "mcr p15, 0, r0, c1, c0  \n"
-        : : : "r0" );
-
     CGU_PLLA = AS3525_PLLA_SETTING;
-    while(!(CGU_INTCTRL & (1<<0))); /* wait until PLLA is locked */
-
-    CGU_PROC = (AS3525_CPU_PREDIV << 2) | 1;
-
-    CGU_PERI |= ((CLK_DIV(AS3525_PLLA_FREQ, AS3525_PCLK_FREQ) - 1) << 2)
-                | 1; /* clk_in = PLLA */
+    while(!(CGU_INTCTRL & (1<<0)));           /* wait until PLLA is locked */
+
+    /*  Set FCLK frequency */
+    CGU_PROC = ((AS3525_FCLK_POSTDIV << 4) |
+                (AS3525_FCLK_PREDIV  << 2) |
+                 AS3525_FCLK_SEL);
+    /*  Set PCLK frequency */
+    CGU_PERI = ((CGU_PERI & 0xffffff80)  |    /* reset divider bits 0:6 */
+                 (AS3525_PCLK_DIV0 << 2) |
+                 (AS3525_PCLK_DIV1 << 6) |
+                  AS3525_PCLK_SEL);
 
-
-    /* FIXME: dcache will not be active, since the mmu is not running
-     * See arm922t datasheet */
     asm volatile(
         "mov r0, #0               \n"
-        "mcr p15, 0, r0, c7, c7   \n" /* invalidate icache & dcache */
-        "mrc p15, 0, r0, c1, c0   \n" /* control register */
-        "orr r0, r0, #0x1000      \n" /* enable icache */
-        "orr r0, r0, #4           \n" /* enable dcache */
+        "mcr p15, 0, r0, c7, c7   \n"      /* invalidate icache & dcache */
+        "mrc p15, 0, r0, c1, c0   \n"      /* control register */
+        "bic r0, r0, #3<<30       \n"      /* clears bus bits & sets fastbus */
+        "orr r0, r0, #1<<12       \n"      /* enable icache */
         "mcr p15, 0, r0, c1, c0   \n"
         : : : "r0" );
 
@@ -281,10 +277,6 @@ void system_init(void)
     fmradio_i2c_init();
 #endif
 #endif /* !BOOTLOADER */
-
-#ifdef HAVE_ADJUSTABLE_CPU_FREQ
-    set_cpu_frequency(CPUFREQ_DEFAULT);
-#endif
 }
 
 void system_reboot(void)
@@ -311,16 +303,34 @@ int system_memory_guard(int newmode)
 #ifdef HAVE_ADJUSTABLE_CPU_FREQ
 void set_cpu_frequency(long frequency)
 {
-    int divider = frequency ? (CPUFREQ_MAX / frequency) : 16 /* minimal */ ;
+    if(frequency == CPUFREQ_MAX)
+    {
 
-    if(divider > 16)
-        divider = 16;
-    else if(divider < 1)
-        divider = 1;
+        asm volatile(
+            "mrc p15, 0, r0, c1, c0  \n"
 
-    cpu_frequency = CPUFREQ_MAX / divider;
+#ifdef ASYNCHRONOUS_BUS
+            "orr r0, r0, #3<<30      \n"   /* asynchronous bus clocking */
+#else
+            "bic r0, r0, #3<<30      \n"   /* clear bus bits */
+            "orr r0, r0, #1<<30      \n"   /* synchronous bus clocking */
+#endif
 
-    CGU_PROC = (CGU_PROC & 0x0f) | ((divider-1) << 4);
+            "mcr p15, 0, r0, c1, c0  \n"
+            : : : "r0" );
+
+        cpu_frequency = CPUFREQ_MAX;
+    }
+    else
+    {
+        asm volatile(
+            "mrc p15, 0, r0, c1, c0  \n"
+            "bic r0, r0, #3<<30      \n"     /* fastbus clocking */
+            "mcr p15, 0, r0, c1, c0  \n"
+            : : : "r0" );
+
+        cpu_frequency = CPUFREQ_NORMAL;
+    }
 }
 #endif /* HAVE_ADJUSTABLE_CPU_FREQ */
-#endif /* BOOTLOADER */
+#endif /* !BOOTLOADER */