u-boot/board/st-ericsson/u8500/prcmu.c
John Rigby afbf88993c armv7: Add support for ST-Ericsson U8500 href platform
Minimal platform support to boot linux from SD.

Supported devices/hw limited to external MMC/SD slot,
GPIO, I2C and minimal PRCMU.

Signed-off-by: John Rigby <john.rigby@linaro.org>
CC: Albert Aribaud <albert.aribaud@free.fr>
2011-06-01 19:31:03 +02:00

166 lines
4.3 KiB
C

/*
* Copyright (C) 2009 ST-Ericsson SA
*
* Adapted from the Linux version:
* Author: Kumar Sanghvi <kumar.sanghvi@stericsson.com>
*
* 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 program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*/
/*
* NOTE: This currently does not support the I2C workaround access method.
*/
#include <common.h>
#include <config.h>
#include <asm/io.h>
#include <asm/arch/hardware.h>
#include <asm/types.h>
#include <asm/io.h>
#include <asm/errno.h>
#include "prcmu-fw.h"
/* CPU mailbox registers */
#define PRCM_MBOX_CPU_VAL (U8500_PRCMU_BASE + 0x0fc)
#define PRCM_MBOX_CPU_SET (U8500_PRCMU_BASE + 0x100)
#define PRCM_MBOX_CPU_CLR (U8500_PRCMU_BASE + 0x104)
static int prcmu_is_ready(void)
{
int ready = readb(PRCM_XP70_CUR_PWR_STATE) == AP_EXECUTE;
if (!ready)
printf("PRCMU firmware not ready\n");
return ready;
}
static int _wait_for_req_complete(int num)
{
int timeout = 1000;
/* checking any already on-going transaction */
while ((readl(PRCM_MBOX_CPU_VAL) & (1 << num)) && timeout--)
;
timeout = 1000;
/* Set an interrupt to XP70 */
writel(1 << num, PRCM_MBOX_CPU_SET);
while ((readl(PRCM_MBOX_CPU_VAL) & (1 << num)) && timeout--)
;
if (!timeout) {
printf("PRCMU operation timed out\n");
return -1;
}
return 0;
}
/**
* prcmu_i2c_read - PRCMU - 4500 communication using PRCMU I2C
* @reg: - db8500 register bank to be accessed
* @slave: - db8500 register to be accessed
* Returns: ACK_MB5 value containing the status
*/
int prcmu_i2c_read(u8 reg, u16 slave)
{
uint8_t i2c_status;
uint8_t i2c_val;
if (!prcmu_is_ready())
return -1;
debug("\nprcmu_4500_i2c_read:bank=%x;reg=%x;\n",
reg, slave);
/* prepare the data for mailbox 5 */
writeb((reg << 1) | I2CREAD, PRCM_REQ_MB5_I2COPTYPE_REG);
writeb((1 << 3) | 0x0, PRCM_REQ_MB5_BIT_FIELDS);
writeb(slave, PRCM_REQ_MB5_I2CSLAVE);
writeb(0, PRCM_REQ_MB5_I2CVAL);
_wait_for_req_complete(REQ_MB5);
/* retrieve values */
debug("ack-mb5:transfer status = %x\n",
readb(PRCM_ACK_MB5_STATUS));
debug("ack-mb5:reg bank = %x\n", readb(PRCM_ACK_MB5) >> 1);
debug("ack-mb5:slave_add = %x\n",
readb(PRCM_ACK_MB5_SLAVE));
debug("ack-mb5:reg_val = %d\n", readb(PRCM_ACK_MB5_VAL));
i2c_status = readb(PRCM_ACK_MB5_STATUS);
i2c_val = readb(PRCM_ACK_MB5_VAL);
if (i2c_status == I2C_RD_OK)
return i2c_val;
else {
printf("prcmu_i2c_read:read return status= %d\n",
i2c_status);
return -1;
}
}
/**
* prcmu_i2c_write - PRCMU-db8500 communication using PRCMU I2C
* @reg: - db8500 register bank to be accessed
* @slave: - db800 register to be written to
* @reg_data: - the data to write
* Returns: ACK_MB5 value containing the status
*/
int prcmu_i2c_write(u8 reg, u16 slave, u8 reg_data)
{
uint8_t i2c_status;
if (!prcmu_is_ready())
return -1;
debug("\nprcmu_4500_i2c_write:bank=%x;reg=%x;\n",
reg, slave);
/* prepare the data for mailbox 5 */
writeb((reg << 1) | I2CWRITE, PRCM_REQ_MB5_I2COPTYPE_REG);
writeb((1 << 3) | 0x0, PRCM_REQ_MB5_BIT_FIELDS);
writeb(slave, PRCM_REQ_MB5_I2CSLAVE);
writeb(reg_data, PRCM_REQ_MB5_I2CVAL);
debug("\ncpu_is_u8500v11\n");
_wait_for_req_complete(REQ_MB5);
/* retrieve values */
debug("ack-mb5:transfer status = %x\n",
readb(PRCM_ACK_MB5_STATUS));
debug("ack-mb5:reg bank = %x\n", readb(PRCM_ACK_MB5) >> 1);
debug("ack-mb5:slave_add = %x\n",
readb(PRCM_ACK_MB5_SLAVE));
debug("ack-mb5:reg_val = %d\n", readb(PRCM_ACK_MB5_VAL));
i2c_status = readb(PRCM_ACK_MB5_STATUS);
debug("\ni2c_status = %x\n", i2c_status);
if (i2c_status == I2C_WR_OK)
return 0;
else {
printf("ape-i2c: i2c_status : 0x%x\n", i2c_status);
return -1;
}
}