Sansa AMS: PCM driver (FS#9592)

Note that on low memory targets (Clip/m200v4 tested) you will encounter
random crashes. Applying FS#9332 seems to help a lot.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19342 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/plugin.lds

@@ -37,6 +37,8 @@ OUTPUT_FORMAT(elf32-sh)
 #include "imx31l.h"
 /* Reserve 1mb for LCD buffer/TTB as in app.lds */
 #define DRAMSIZE (MEMORYSIZE * 0x100000 - 0x100000) - PLUGIN_BUFFER_SIZE - STUBOFFSET - CODEC_SIZE
+#elif CONFIG_CPU==AS3525 && MEMORYSIZE <= 2
+#define DRAMSIZE (MEMORYSIZE * 0x100000) - PLUGIN_BUFFER_SIZE - STUBOFFSET
 #else
 #define DRAMSIZE (MEMORYSIZE * 0x100000) - PLUGIN_BUFFER_SIZE - STUBOFFSET - CODEC_SIZE
 #endif
@@ -87,17 +89,29 @@ OUTPUT_FORMAT(elf32-sh)
 #define IRAM DRAM
 #define IRAMSIZE 0
 #elif CONFIG_CPU==AS3525
+#if MEMORYSIZE <= 2
+#define IRAMSIZE 0  /* simulates no IRAM since codec is already entirely in IRAM */
+#define CODEC_ORIGIN (0x50000 - CODEC_SIZE)
+#define PLUGIN_ORIGIN (DRAMORIG + DRAMSIZE)
+#else
 #define IRAMORIG 0x0
 #define IRAMSIZE 0x50000
+#endif
 #define DRAMORIG 0x30000000
+
 #else
 #define DRAMORIG 0x09000000 + STUBOFFSET
 #endif
 
 #define PLUGIN_LENGTH PLUGIN_BUFFER_SIZE
 
+#ifndef CODEC_ORIGIN /* targets can specify another origin */
 #define CODEC_ORIGIN (DRAMORIG + (DRAMSIZE))
+#endif
+
+#ifndef PLUGIN_ORIGIN /* targets can specify another origin */
 #define PLUGIN_ORIGIN (CODEC_ORIGIN + CODEC_SIZE)
+#endif
 
 #ifdef CODEC
 #define THIS_LENGTH CODEC_SIZE

firmware/export/config-clip.h

@@ -95,10 +95,10 @@
 #define HAVE_FAT16SUPPORT
 
 /* The number of bytes reserved for loadable codecs */
-#define CODEC_SIZE 0x80000  /* TODO : check if we can use IRAM */
+#define CODEC_SIZE 0x48000  /* in IRAM */
 
 /* The number of bytes reserved for loadable plugins */
-#define PLUGIN_BUFFER_SIZE 0x80000
+#define PLUGIN_BUFFER_SIZE 0x60000
 
 #define AB_REPEAT_ENABLE 1
 

firmware/export/config-m200v4.h

@@ -73,14 +73,10 @@
 #define HAVE_SW_POWEROFF
 
 /* The number of bytes reserved for loadable codecs */
-#define CODEC_SIZE 0x100000
+#define CODEC_SIZE 0x48000 /* in IRAM */
 
 /* The number of bytes reserved for loadable plugins */
-#if 0 /* The plugin buffer doesn't fit in the 2MB memory */
-#define PLUGIN_BUFFER_SIZE 0x80000
-#else
-#define PLUGIN_BUFFER_SIZE 0
-#endif
+#define PLUGIN_BUFFER_SIZE 0x60000
 
 #define AB_REPEAT_ENABLE 1
 

firmware/target/arm/as3525/app.lds

@@ -6,6 +6,11 @@ OUTPUT_FORMAT(elf32-littlearm)
 OUTPUT_ARCH(arm)
 STARTUP(target/arm/crt0.o)
 
+#if MEMORYSIZE <= 2
+/* we put the codec buffer in IRAM */
+#define LOWMEM
+#endif
+
 #define PLUGINSIZE PLUGIN_BUFFER_SIZE
 #define CODECSIZE CODEC_SIZE
 
@@ -16,8 +21,15 @@ STARTUP(target/arm/crt0.o)
 #endif
 
 #include "cpu.h"
+
 #define IRAMSIZE 0x50000
+
+#ifdef LOWMEM
+#define DRAMSIZE (MEMORYSIZE * 0x100000) - STUBOFFSET - PLUGINSIZE
+#define CODECORIG (IRAMORIG + IRAMSIZE - CODEC_SIZE)
+#else
 #define DRAMSIZE (MEMORYSIZE * 0x100000) - STUBOFFSET - PLUGINSIZE - CODECSIZE
+#endif
 
 #define IRAMORIG 0x0
 #define DRAMORIG 0x30000000 + STUBOFFSET
@@ -26,11 +38,20 @@ STARTUP(target/arm/crt0.o)
 #define ENDAUDIOADDR  (DRAMORIG + DRAMSIZE)
 
 /* Where the codec buffer ends, and the plugin buffer starts */
+#ifdef LOWMEM
+#define ENDADDR (ENDAUDIOADDR)
+#else
 #define ENDADDR (ENDAUDIOADDR + CODECSIZE)
+#endif
 
 MEMORY
 {
+#ifdef LOWMEM
+    IRAM : ORIGIN = IRAMORIG, LENGTH = (IRAMSIZE - CODEC_SIZE)
+    CODEC_IRAM : ORIGIN = CODECORIG, LENGTH = CODEC_SIZE
+#else
     IRAM : ORIGIN = IRAMORIG, LENGTH = IRAMSIZE
+#endif
     DRAM : ORIGIN = DRAMORIG, LENGTH = DRAMSIZE
 }
 
@@ -69,8 +90,6 @@ SECTIONS
         *(.eh_frame)
     }
 
-    _initdata_end =.;
-
     .vectors IRAMORIG:
     {
         _vectors_start = .;
@@ -79,6 +98,16 @@ SECTIONS
 
     _vectorscopy = LOADADDR(.vectors);
 
+    .iram :
+    {
+        _iramstart = .;
+        *(.icode)
+        *(.irodata)
+        *(.idata)
+        . = ALIGN(0x4);
+        _iramend = .;
+    } > IRAM AT> DRAM
+
     .ibss (NOLOAD) :
     {
         _iedata = .;
@@ -88,16 +117,6 @@ SECTIONS
         _iend = .;
     } > IRAM
 
-    .iram _iend :
-    {
-        _iramstart = .;
-        *(.icode)
-        *(.irodata)
-        *(.idata)
-        . = ALIGN(0x4);
-        _iramend = .;
-    } > IRAM AT> DRAM
-
     _iramcopy = LOADADDR(.iram);
 
     .stack (NOLOAD) :
@@ -130,15 +149,19 @@ SECTIONS
         _audiobufend = .;
     } > DRAM
 
-    .codec ENDAUDIOADDR  (NOLOAD) :
+    .codec CODECORIG (NOLOAD) :
     {
         codecbuf = .;
         _codecbuf = .;
-    }
+#ifdef LOWMEM
+    } > CODEC_IRAM
+#else
+    } > DRAM
+#endif
 
     .plugin ENDADDR (NOLOAD) :
     {
         _pluginbuf = .;
         pluginbuf = .;
-    }
+    } > DRAM
 }

firmware/target/arm/as3525/pcm-as3525.c

@@ -21,58 +21,140 @@
 #include "system.h"
 #include "audio.h"
 #include "string.h"
+#include "as3525.h"
+#include "pl081.h"
+#include "dma-target.h"
+#include "clock-target.h"
+#include "panic.h"
+#include "as3514.h"
+#include "audiohw.h"
 
-/* TODO */
+#define MAX_TRANSFER (4*((1<<11)-1)) /* maximum data we can transfer via DMA
+                                      * i.e. 32 bits at once (size of I2SO_DATA)
+                                      * and the number of 32bits words has to
+                                      * fit in 11 bits of DMA register */
 
+static unsigned char *dma_start_addr;
+static size_t      dma_size;   /* in 4*32 bits */
+static void dma_callback(void);
+static int locked = 0;
+
+/* Mask the DMA interrupt */
 void pcm_play_lock(void)
 {
+    if(++locked == 1)
+        VIC_INT_EN_CLEAR |= INTERRUPT_DMAC;
 }
 
+/* Unmask the DMA interrupt if enabled */
 void pcm_play_unlock(void)
 {
+    if(--locked == 0)
+        VIC_INT_ENABLE |= INTERRUPT_DMAC;
+}
+
+static void play_start_pcm(void)
+{
+    const unsigned char* addr = dma_start_addr;
+    size_t size = dma_size;
+    if(size > MAX_TRANSFER)
+        size = MAX_TRANSFER;
+
+    if((unsigned int)dma_start_addr & 3)
+        panicf("unaligned pointer!");
+
+    dma_size -= size;
+    dma_start_addr += size;
+
+    dma_enable_channel(1, (void*)addr, (void*)I2SOUT_DATA, DMA_PERI_I2SOUT,
+                DMAC_FLOWCTRL_DMAC_MEM_TO_PERI, true, false, size >> 2, DMA_S1,
+                dma_callback);
+}
+
+static void dma_callback(void)
+{
+    if(!dma_size)
+    {
+        register pcm_more_callback_type get_more = pcm_callback_for_more;
+        if(get_more)
+            get_more(&dma_start_addr, &dma_size);
+    }
+
+    if(!dma_size)
+        pcm_play_dma_stop();
+    else
+        play_start_pcm();
 }
 
 void pcm_play_dma_start(const void *addr, size_t size)
 {
+    dma_size = size;
+    dma_start_addr = (unsigned char*)addr;
+
+    play_start_pcm();
 }
 
 void pcm_play_dma_stop(void)
 {
+    dma_disable_channel(1);
+    dma_size = 0;
 }
 
 void pcm_play_dma_pause(bool pause)
 {
-}
-
-unsigned long physical_address(void *p)
-{
-    return 0;
+    if(pause)
+        dma_disable_channel(1);
+    else
+        play_start_pcm();
 }
 
 void pcm_play_dma_init(void)
 {
+    CGU_PERI |= CGU_I2SOUT_APB_CLOCK_ENABLE;
+
+    /* enable I2SO_MCLK, clock source PLLA, minimal frequency */
+    CGU_AUDIO |= (1<<11) | (511<<2) | (1<<0);
+
+    I2SOUT_CONTROL |= (1<<6) ;  /* enable dma */
+    I2SOUT_CONTROL |= (1<<3) ;  /* stereo */
+    I2SOUT_CONTROL &= ~(1<<2);  /* 16 bit samples */
+
+    audiohw_preinit();
 }
 
 void pcm_postinit(void)
 {
+    audiohw_postinit();
+    pcm_apply_settings();
 }
 
 void pcm_set_frequency(unsigned int frequency)
 {
+    const int divider = (((AS3525_PLLA_FREQ/128) + (frequency/2)) / frequency) - 1;
+    if(divider < 0 || divider > 511)
+        panicf("unsupported frequency %d", frequency);
+
+    CGU_AUDIO &= ~(((511 ^ divider) << 2) /* I2SOUT */
+            /*| ((511 ^ divider) << 14) */ /* I2SIN */
+            );
+
+    pcm_curr_sampr = frequency;
 }
 
 void pcm_apply_settings(void)
 {
+    pcm_set_frequency(HW_SAMPR_DEFAULT);
 }
 
 size_t pcm_get_bytes_waiting(void)
 {
-    return 0;
+    return dma_size;
 }
 
 const void * pcm_play_dma_get_peak_buffer(int *count)
 {
-    return NULL;
+    *count = dma_size >> 2;
+    return (const void*)dma_start_addr;
 }