rockbox/firmware/target/arm/imx31/gigabeat-s/pcm-imx31.c
2008-12-12 12:46:57 +00:00

288 lines
7.7 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2008 by Michael Sevakis
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdlib.h>
#include "system.h"
#include "kernel.h"
#include "audio.h"
#include "sound.h"
#include "avic-imx31.h"
#include "clkctl-imx31.h"
/* This isn't DMA-based at the moment and is handled like Portal Player but
* will suffice for starters. */
struct dma_data
{
uint16_t *p;
size_t size;
int locked;
int state;
};
static struct dma_data dma_play_data =
{
/* Initialize to a locked, stopped state */
.p = NULL,
.size = 0,
.locked = 0,
.state = 0
};
void pcm_play_lock(void)
{
if (++dma_play_data.locked == 1)
{
/* Atomically disable transmit interrupt */
imx31_regmod32(&SSI_SIER1, 0, SSI_SIER_TIE);
}
}
void pcm_play_unlock(void)
{
if (--dma_play_data.locked == 0 && dma_play_data.state != 0)
{
/* Atomically enable transmit interrupt */
imx31_regmod32(&SSI_SIER1, SSI_SIER_TIE, SSI_SIER_TIE);
}
}
static void __attribute__((interrupt("IRQ"))) SSI1_HANDLER(void)
{
register pcm_more_callback_type get_more;
do
{
while (dma_play_data.size > 0)
{
if (SSI_SFCSR_TFCNT0r(SSI_SFCSR1) > 6)
{
return;
}
SSI_STX0_1 = *dma_play_data.p++;
SSI_STX0_1 = *dma_play_data.p++;
dma_play_data.size -= 4;
}
/* p is empty, get some more data */
get_more = pcm_callback_for_more;
if (get_more)
{
get_more((unsigned char **)&dma_play_data.p,
&dma_play_data.size);
}
}
while (dma_play_data.size > 0);
/* No more data, so disable the FIFO/interrupt */
pcm_play_dma_stop();
pcm_play_dma_stopped_callback();
}
void pcm_dma_apply_settings(void)
{
audiohw_set_frequency(pcm_fsel);
}
void pcm_play_dma_init(void)
{
imx31_clkctl_module_clock_gating(CG_SSI1, CGM_ON_ALL);
imx31_clkctl_module_clock_gating(CG_SSI2, CGM_ON_ALL);
/* Reset & disable SSIs */
SSI_SCR2 &= ~SSI_SCR_SSIEN;
SSI_SCR1 &= ~SSI_SCR_SSIEN;
SSI_SIER1 = SSI_SIER_TFE0;
SSI_SIER2 = 0;
/* Set up audio mux */
/* Port 1 (internally connected to SSI1)
* All clocking is output sourced from port 4 */
AUDMUX_PTCR1 = AUDMUX_PTCR_TFS_DIR | AUDMUX_PTCR_TFSEL_PORT4 |
AUDMUX_PTCR_TCLKDIR | AUDMUX_PTCR_TCSEL_PORT4 |
AUDMUX_PTCR_RFSDIR | AUDMUX_PTCR_RFSSEL_PORT4 |
AUDMUX_PTCR_RCLKDIR | AUDMUX_PTCR_RCSEL_PORT4 |
AUDMUX_PTCR_SYN;
/* Receive data from port 4 */
AUDMUX_PDCR1 = AUDMUX_PDCR_RXDSEL_PORT4;
/* All clock lines are inputs sourced from the master mode codec and
* sent back to SSI1 through port 1 */
AUDMUX_PTCR4 = AUDMUX_PTCR_SYN;
/* Receive data from port 1 */
AUDMUX_PDCR4 = AUDMUX_PDCR_RXDSEL_PORT1;
/* Port 2 (internally connected to SSI2) routes clocking to port 5 to
* provide MCLK to the codec */
/* All port 2 clocks are inputs taken from SSI2 */
AUDMUX_PTCR2 = 0;
AUDMUX_PDCR2 = 0;
/* Port 5 outputs TCLK sourced from port 2 */
AUDMUX_PTCR5 = AUDMUX_PTCR_TCLKDIR | AUDMUX_PTCR_TCSEL_PORT2;
AUDMUX_PDCR5 = 0;
/* Setup SSIs */
/* SSI1 - interface for all I2S data */
SSI_SCR1 = SSI_SCR_SYN | SSI_SCR_I2S_MODE_SLAVE;
SSI_STCR1 = SSI_STCR_TXBIT0 | SSI_STCR_TSCKP | SSI_STCR_TFSI |
SSI_STCR_TEFS | SSI_STCR_TFEN0;
/* 16 bits per word, 2 words per frame */
SSI_STCCR1 = SSI_STRCCR_WL16 | SSI_STRCCR_DCw(2-1) |
SSI_STRCCR_PMw(4-1);
SSI_STMSK1 = 0;
/* Receive */
SSI_SRCR1 = SSI_SRCR_RXBIT0 | SSI_SRCR_RSCKP | SSI_SRCR_RFSI |
SSI_SRCR_REFS | SSI_SRCR_RFEN0;
/* 16 bits per word, 2 words per frame */
SSI_SRCCR1 = SSI_STRCCR_WL16 | SSI_STRCCR_DCw(2-1) |
SSI_STRCCR_PMw(4-1);
/* Receive high watermark - 6 samples in FIFO
* Transmit low watermark - 2 samples in FIFO */
SSI_SFCSR1 = SSI_SFCSR_RFWM1w(8) | SSI_SFCSR_TFWM1w(1) |
SSI_SFCSR_RFWM0w(6) | SSI_SFCSR_TFWM0w(2);
SSI_SRMSK1 = 0;
/* SSI2 - provides MCLK only */
SSI_SCR2 = 0;
SSI_SRCR2 = 0;
SSI_STCR2 = SSI_STCR_TXDIR;
/* f(INT_BIT_CLK) =
* f(SYS_CLK) / [(DIV2 + 1)*(7*PSR + 1)*(PM + 1)*2] =
* 677737600 / [(1 + 1)*(7*0 + 1)*(0 + 1)*2] =
* 677737600 / 4 = 169344000 Hz
*
* 45.4.2.2 DIV2, PSR, and PM Bit Description states:
* Bits DIV2, PSR, and PM should not be all set to zero at the same
* time.
*
* The hardware seems to force a divide by 4 even if all bits are
* zero but comply by setting DIV2 and the others to zero.
*/
SSI_STCCR2 = SSI_STRCCR_DIV2 | SSI_STRCCR_PMw(1-1);
/* Enable SSI2 (codec clock) */
SSI_SCR2 |= SSI_SCR_SSIEN;
audiohw_init();
}
void pcm_postinit(void)
{
audiohw_postinit();
avic_enable_int(SSI1, IRQ, 8, SSI1_HANDLER);
}
static void play_start_pcm(void)
{
/* Stop transmission (if in progress) */
SSI_SCR1 &= ~SSI_SCR_TE;
/* Enable interrupt on unlock */
dma_play_data.state = 1;
/* Fill the FIFO or start when data is used up */
SSI_SCR1 |= SSI_SCR_SSIEN; /* Enable SSI */
while (1)
{
if (SSI_SFCSR_TFCNT0r(SSI_SFCSR1) > 6 || dma_play_data.size == 0)
{
SSI_SCR1 |= SSI_SCR_TE; /* Start transmitting */
return;
}
SSI_STX0_1 = *dma_play_data.p++;
SSI_STX0_1 = *dma_play_data.p++;
dma_play_data.size -= 4;
}
}
static void play_stop_pcm(void)
{
/* Disable interrupt */
SSI_SIER1 &= ~SSI_SIER_TIE;
/* Wait for FIFO to empty */
while (SSI_SFCSR_TFCNT0r(SSI_SFCSR1) > 0);
/* Disable transmission */
SSI_SCR1 &= ~(SSI_SCR_TE | SSI_SCR_SSIEN);
/* Do not enable interrupt on unlock */
dma_play_data.state = 0;
}
void pcm_play_dma_start(const void *addr, size_t size)
{
dma_play_data.p = (void *)(((uintptr_t)addr + 3) & ~3);
dma_play_data.size = (size & ~3);
play_start_pcm();
}
void pcm_play_dma_stop(void)
{
play_stop_pcm();
dma_play_data.size = 0;
}
void pcm_play_dma_pause(bool pause)
{
if (pause)
{
play_stop_pcm();
}
else
{
uint32_t addr = (uint32_t)dma_play_data.p;
dma_play_data.p = (void *)((addr + 2) & ~3);
dma_play_data.size &= ~3;
play_start_pcm();
}
}
/* Return the number of bytes waiting - full L-R sample pairs only */
size_t pcm_get_bytes_waiting(void)
{
return dma_play_data.size & ~3;
}
/* Return a pointer to the samples and the number of them in *count */
const void * pcm_play_dma_get_peak_buffer(int *count)
{
uint32_t addr = (uint32_t)dma_play_data.p;
size_t cnt = dma_play_data.size;
*count = cnt >> 2;
return (void *)((addr + 2) & ~3);
}
/* Any recording functionality should be implemented similarly */