LXR uboot/board/st-ericsson/u8500/prcmu.c

   1/*
   2 * Copyright (C) 2009 ST-Ericsson SA
   3 *
   4 * Adapted from the Linux version:
   5 * Author: Kumar Sanghvi <kumar.sanghvi@stericsson.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation; either version 2 of the License, or
  10 * (at your option) any later version.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program; if not, write to the Free Software
  19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 * This program is free software; you can redistribute it and/or modify
  21 * it under the terms of the GNU General Public License version 2
  22 * as published by the Free Software Foundation.
  23 */
  24
  25/*
  26 * NOTE: This currently does not support the I2C workaround access method.
  27 */
  28
  29#include <common.h>
  30#include <config.h>
  31#include <asm/io.h>
  32#include <asm/arch/hardware.h>
  33#include <asm/types.h>
  34#include <asm/io.h>
  35#include <asm/errno.h>
  36
  37#include "prcmu-fw.h"
  38
  39/* CPU mailbox registers */
  40#define PRCM_MBOX_CPU_VAL (U8500_PRCMU_BASE + 0x0fc)
  41#define PRCM_MBOX_CPU_SET (U8500_PRCMU_BASE + 0x100)
  42#define PRCM_MBOX_CPU_CLR (U8500_PRCMU_BASE + 0x104)
  43
  44static int prcmu_is_ready(void)
  45{
  46        int ready = readb(PRCM_XP70_CUR_PWR_STATE) == AP_EXECUTE;
  47        if (!ready)
  48                printf("PRCMU firmware not ready\n");
  49        return ready;
  50}
  51
  52static int _wait_for_req_complete(int num)
  53{
  54        int timeout = 1000;
  55
  56        /* checking any already on-going transaction */
  57        while ((readl(PRCM_MBOX_CPU_VAL) & (1 << num)) && timeout--)
  58                ;
  59
  60        timeout = 1000;
  61
  62        /* Set an interrupt to XP70 */
  63        writel(1 << num, PRCM_MBOX_CPU_SET);
  64
  65        while ((readl(PRCM_MBOX_CPU_VAL) & (1 << num)) && timeout--)
  66                ;
  67
  68        if (!timeout) {
  69                printf("PRCMU operation timed out\n");
  70                return -1;
  71        }
  72
  73        return 0;
  74}
  75
  76/**
  77 * prcmu_i2c_read - PRCMU - 4500 communication using PRCMU I2C
  78 * @reg: - db8500 register bank to be accessed
  79 * @slave:  - db8500 register to be accessed
  80 * Returns: ACK_MB5  value containing the status
  81 */
  82int prcmu_i2c_read(u8 reg, u16 slave)
  83{
  84        uint8_t i2c_status;
  85        uint8_t i2c_val;
  86
  87        if (!prcmu_is_ready())
  88                return -1;
  89
  90        debug("\nprcmu_4500_i2c_read:bank=%x;reg=%x;\n",
  91                        reg, slave);
  92
  93        /* prepare the data for mailbox 5 */
  94        writeb((reg << 1) | I2CREAD, PRCM_REQ_MB5_I2COPTYPE_REG);
  95        writeb((1 << 3) | 0x0, PRCM_REQ_MB5_BIT_FIELDS);
  96        writeb(slave, PRCM_REQ_MB5_I2CSLAVE);
  97        writeb(0, PRCM_REQ_MB5_I2CVAL);
  98
  99        _wait_for_req_complete(REQ_MB5);
 100
 101        /* retrieve values */
 102        debug("ack-mb5:transfer status = %x\n",
 103                        readb(PRCM_ACK_MB5_STATUS));
 104        debug("ack-mb5:reg bank = %x\n", readb(PRCM_ACK_MB5) >> 1);
 105        debug("ack-mb5:slave_add = %x\n",
 106                        readb(PRCM_ACK_MB5_SLAVE));
 107        debug("ack-mb5:reg_val = %d\n", readb(PRCM_ACK_MB5_VAL));
 108
 109        i2c_status = readb(PRCM_ACK_MB5_STATUS);
 110        i2c_val = readb(PRCM_ACK_MB5_VAL);
 111
 112        if (i2c_status == I2C_RD_OK)
 113                return i2c_val;
 114        else {
 115
 116                printf("prcmu_i2c_read:read return status= %d\n",
 117                                i2c_status);
 118                return -1;
 119        }
 120
 121}
 122
 123/**
 124 * prcmu_i2c_write - PRCMU-db8500 communication using PRCMU I2C
 125 * @reg: - db8500 register bank to be accessed
 126 * @slave:  - db800 register to be written to
 127 * @reg_data: - the data to write
 128 * Returns: ACK_MB5 value containing the status
 129 */
 130int prcmu_i2c_write(u8 reg, u16 slave, u8 reg_data)
 131{
 132        uint8_t i2c_status;
 133
 134        if (!prcmu_is_ready())
 135                return -1;
 136
 137        debug("\nprcmu_4500_i2c_write:bank=%x;reg=%x;\n",
 138                        reg, slave);
 139
 140        /* prepare the data for mailbox 5 */
 141        writeb((reg << 1) | I2CWRITE, PRCM_REQ_MB5_I2COPTYPE_REG);
 142        writeb((1 << 3) | 0x0, PRCM_REQ_MB5_BIT_FIELDS);
 143        writeb(slave, PRCM_REQ_MB5_I2CSLAVE);
 144        writeb(reg_data, PRCM_REQ_MB5_I2CVAL);
 145
 146        debug("\ncpu_is_u8500v11\n");
 147        _wait_for_req_complete(REQ_MB5);
 148
 149        /* retrieve values */
 150        debug("ack-mb5:transfer status = %x\n",
 151                        readb(PRCM_ACK_MB5_STATUS));
 152        debug("ack-mb5:reg bank = %x\n", readb(PRCM_ACK_MB5) >> 1);
 153        debug("ack-mb5:slave_add = %x\n",
 154                        readb(PRCM_ACK_MB5_SLAVE));
 155        debug("ack-mb5:reg_val = %d\n", readb(PRCM_ACK_MB5_VAL));
 156
 157        i2c_status = readb(PRCM_ACK_MB5_STATUS);
 158        debug("\ni2c_status = %x\n", i2c_status);
 159        if (i2c_status == I2C_WR_OK)
 160                return 0;
 161        else {
 162                printf("ape-i2c: i2c_status : 0x%x\n", i2c_status);
 163                return -1;
 164        }
 165}
 166