rockbox/firmware/target/arm/s5l8702/spi-s5l8702.c
Cástor Muñoz 57a44854e3 iPod Classic: SPI driver for bootloader
Based on emCORE.

Low level functions that do not depend on Rockbox kernel,
intended to be used by the bootloader, dualboot-installer,
RB drivers or other .dfu tools.

Change-Id: Iad369627b55bf1778eab437424072f1a653e4db6
2016-08-19 00:15:36 +02:00

112 lines
3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id:
*
* Copyright © 2009 Michael Sparmann
*
* 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 <stdint.h>
#include <stdbool.h>
#include "config.h"
#include "s5l8702.h"
#include "clocking-s5l8702.h"
#include "spi-s5l8702.h"
#define SPI_N_PORT 3
static int clkdiv[SPI_N_PORT] = {4, 4, 4};
/* configure SPI clock, speed is PClk/(div+1) (TBC) */
void spi_clkdiv(int port, int div)
{
clkdiv[port] = div;
}
/* state: 1 -> route GPIO ports to SPI controller
* 0 -> set GPIO to lowest power consumption
*/
void spi_init(int port, bool state)
{
uint32_t val = state ? 0x2222 : 0xEEEF;
switch (port)
{
case 0:
PCON0 = (PCON0 & ~0xffff) | val;
break;
case 1:
PCON6 = (PCON6 & ~0xffff0000) | (val << 16);
break;
case 2:
PCONE = (PCONE & ~0xff000000) | (val << 24);
PCONF = (PCONF & ~0xff) | (val >> 8);
break;
}
}
/* nSS pin: output LOW -> external device SLAVE
* output HIGH -> deactivate external SLAVE device
* input LOW -> SLAVE condition (external MASTER device)
*/
void spi_ce(int port, bool state)
{
uint32_t level = state ? 0 : 1;
switch (port)
{
case 0: GPIOCMD = 0x0000e | level; break;
case 1: GPIOCMD = 0x6040e | level; break;
case 2: GPIOCMD = 0xe060e | level; break;
}
}
void spi_prepare(int port)
{
clockgate_enable(SPICLKGATE(port), true);
SPISTATUS(port) = 0xf;
SPICTRL(port) |= 0xc;
SPICLKDIV(port) = clkdiv[port];
SPIPIN(port) = 6;
SPISETUP(port) = 0x10618;
SPICTRL(port) |= 0xc;
SPICTRL(port) = 1;
}
void spi_release(int port)
{
clockgate_enable(SPICLKGATE(port), false);
}
uint32_t spi_write(int port, uint32_t data)
{
SPIRXLIMIT(port) = 1;
while ((SPISTATUS(port) & 0x1f0) == 0x100);
SPITXDATA(port) = data;
while (!(SPISTATUS(port) & 0x3e00));
return SPIRXDATA(port);
}
void spi_read(int port, uint32_t size, void* buf)
{
uint8_t* buffer = (uint8_t*)buf;
SPIRXLIMIT(port) = size;
SPISETUP(port) |= 1;
while (size--)
{
while (!(SPISTATUS(port) & 0x3e00));
*buffer++ = SPIRXDATA(port);
}
SPISETUP(port) &= ~1;
}