arch/arm/mach-omap2/prminst44xx.c

   1 /*
   2  * OMAP4 PRM instance functions
   3  *
   4  * Copyright (C) 2009 Nokia Corporation
   5  * Copyright (C) 2011 Texas Instruments, Inc.
   6  * Paul Walmsley
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/types.h>
  15 #include <linux/errno.h>
  16 #include <linux/err.h>
  17 #include <linux/io.h>
  18
  19 #include <plat/common.h>
  20
  21 #include "prm44xx.h"
  22 #include "prminst44xx.h"
  23 #include "prm-regbits-44xx.h"
  24 #include "prcm44xx.h"
  25 #include "prcm_mpu44xx.h"
  26
  27 static u32 _prm_bases[OMAP4_MAX_PRCM_PARTITIONS] = {
  28         [OMAP4430_INVALID_PRCM_PARTITION]       = 0,
  29         [OMAP4430_PRM_PARTITION]                = OMAP4430_PRM_BASE,
  30         [OMAP4430_CM1_PARTITION]                = 0,
  31         [OMAP4430_CM2_PARTITION]                = 0,
  32         [OMAP4430_SCRM_PARTITION]               = 0,
  33         [OMAP4430_PRCM_MPU_PARTITION]           = OMAP4430_PRCM_MPU_BASE,
  34 };
  35
  36 /* Read a register in a PRM instance */
  37 u32 omap4_prminst_read_inst_reg(u8 part, s16 inst, u16 idx)
  38 {
  39         BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
  40                part == OMAP4430_INVALID_PRCM_PARTITION ||
  41                !_prm_bases[part]);
  42         return __raw_readl(OMAP2_L4_IO_ADDRESS(_prm_bases[part] + inst +
  43                                                idx));
  44 }
  45
  46 /* Write into a register in a PRM instance */
  47 void omap4_prminst_write_inst_reg(u32 val, u8 part, s16 inst, u16 idx)
  48 {
  49         BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
  50                part == OMAP4430_INVALID_PRCM_PARTITION ||
  51                !_prm_bases[part]);
  52         __raw_writel(val, OMAP2_L4_IO_ADDRESS(_prm_bases[part] + inst + idx));
  53 }
  54
  55 /* Read-modify-write a register in PRM. Caller must lock */
  56 u32 omap4_prminst_rmw_inst_reg_bits(u32 mask, u32 bits, u8 part, s16 inst,
  57                                     u16 idx)
  58 {
  59         u32 v;
  60
  61         v = omap4_prminst_read_inst_reg(part, inst, idx);
  62         v &= ~mask;
  63         v |= bits;
  64         omap4_prminst_write_inst_reg(v, part, inst, idx);
  65
  66         return v;
  67 }
  68
  69 /*
  70  * Address offset (in bytes) between the reset control and the reset
  71  * status registers: 4 bytes on OMAP4
  72  */
  73 #define OMAP4_RST_CTRL_ST_OFFSET                4
  74
  75 /**
  76  * omap4_prminst_is_hardreset_asserted - read the HW reset line state of
  77  * submodules contained in the hwmod module
  78  * @rstctrl_reg: RM_RSTCTRL register address for this module
  79  * @shift: register bit shift corresponding to the reset line to check
  80  *
  81  * Returns 1 if the (sub)module hardreset line is currently asserted,
  82  * 0 if the (sub)module hardreset line is not currently asserted, or
  83  * -EINVAL upon parameter error.
  84  */
  85 int omap4_prminst_is_hardreset_asserted(u8 shift, u8 part, s16 inst,
  86                                         u16 rstctrl_offs)
  87 {
  88         u32 v;
  89
  90         v = omap4_prminst_read_inst_reg(part, inst, rstctrl_offs);
  91         v &= 1 << shift;
  92         v >>= shift;
  93
  94         return v;
  95 }
  96
  97 /**
  98  * omap4_prminst_assert_hardreset - assert the HW reset line of a submodule
  99  * @rstctrl_reg: RM_RSTCTRL register address for this module
 100  * @shift: register bit shift corresponding to the reset line to assert
 101  *
 102  * Some IPs like dsp, ipu or iva contain processors that require an HW
 103  * reset line to be asserted / deasserted in order to fully enable the
 104  * IP.  These modules may have multiple hard-reset lines that reset
 105  * different 'submodules' inside the IP block.  This function will
 106  * place the submodule into reset.  Returns 0 upon success or -EINVAL
 107  * upon an argument error.
 108  */
 109 int omap4_prminst_assert_hardreset(u8 shift, u8 part, s16 inst,
 110                                    u16 rstctrl_offs)
 111 {
 112         u32 mask = 1 << shift;
 113
 114         omap4_prminst_rmw_inst_reg_bits(mask, mask, part, inst, rstctrl_offs);
 115
 116         return 0;
 117 }
 118
 119 /**
 120  * omap4_prminst_deassert_hardreset - deassert a submodule hardreset line and
 121  * wait
 122  * @rstctrl_reg: RM_RSTCTRL register address for this module
 123  * @shift: register bit shift corresponding to the reset line to deassert
 124  *
 125  * Some IPs like dsp, ipu or iva contain processors that require an HW
 126  * reset line to be asserted / deasserted in order to fully enable the
 127  * IP.  These modules may have multiple hard-reset lines that reset
 128  * different 'submodules' inside the IP block.  This function will
 129  * take the submodule out of reset and wait until the PRCM indicates
 130  * that the reset has completed before returning.  Returns 0 upon success or
 131  * -EINVAL upon an argument error, -EEXIST if the submodule was already out
 132  * of reset, or -EBUSY if the submodule did not exit reset promptly.
 133  */
 134 int omap4_prminst_deassert_hardreset(u8 shift, u8 part, s16 inst,
 135                                      u16 rstctrl_offs)
 136 {
 137         int c;
 138         u32 mask = 1 << shift;
 139         u16 rstst_offs = rstctrl_offs + OMAP4_RST_CTRL_ST_OFFSET;
 140
 141         /* Check the current status to avoid de-asserting the line twice */
 142         if (omap4_prminst_is_hardreset_asserted(shift, part, inst,
 143                                                 rstctrl_offs) == 0)
 144                 return -EEXIST;
 145
 146         /* Clear the reset status by writing 1 to the status bit */
 147         omap4_prminst_rmw_inst_reg_bits(0xffffffff, mask, part, inst,
 148                                         rstst_offs);
 149         /* de-assert the reset control line */
 150         omap4_prminst_rmw_inst_reg_bits(mask, 0, part, inst, rstctrl_offs);
 151         /* wait the status to be set */
 152         omap_test_timeout(omap4_prminst_is_hardreset_asserted(shift, part, inst,
 153                                                               rstst_offs),
 154                           MAX_MODULE_HARDRESET_WAIT, c);
 155
 156         return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
 157 }
 158
 159
 160 void omap4_prminst_global_warm_sw_reset(void)
 161 {
 162         u32 v;
 163
 164         v = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
 165                                     OMAP4430_PRM_DEVICE_INST,
 166                                     OMAP4_PRM_RSTCTRL_OFFSET);
 167         v |= OMAP4430_RST_GLOBAL_WARM_SW_MASK;
 168         omap4_prminst_write_inst_reg(v, OMAP4430_PRM_PARTITION,
 169                                  OMAP4430_PRM_DEVICE_INST,
 170                                  OMAP4_PRM_RSTCTRL_OFFSET);
 171
 172         /* OCP barrier */
 173         v = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
 174                                     OMAP4430_PRM_DEVICE_INST,
 175                                     OMAP4_PRM_RSTCTRL_OFFSET);
 176 }