aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/mach-omap2/prminst44xx.c
blob: c12320c0ae952e46d05a40d50d6d260994ff98d7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
/*
 * OMAP4 PRM instance functions
 *
 * Copyright (C) 2009 Nokia Corporation
 * Copyright (C) 2011 Texas Instruments, Inc.
 * Paul Walmsley
 *
 * 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.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/io.h>

#include "iomap.h"
#include "common.h"
#include "prcm-common.h"
#include "prm44xx.h"
#include "prminst44xx.h"
#include "prm-regbits-44xx.h"
#include "prcm44xx.h"
#include "prcm_mpu44xx.h"

static void __iomem *_prm_bases[OMAP4_MAX_PRCM_PARTITIONS];

/**
 * omap_prm_base_init - Populates the prm partitions
 *
 * Populates the base addresses of the _prm_bases
 * array used for read/write of prm module registers.
 */
void omap_prm_base_init(void)
{
	_prm_bases[OMAP4430_PRM_PARTITION] = prm_base;
	_prm_bases[OMAP4430_PRCM_MPU_PARTITION] = prcm_mpu_base;
}

/* Read a register in a PRM instance */
u32 omap4_prminst_read_inst_reg(u8 part, s16 inst, u16 idx)
{
	BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
	       part == OMAP4430_INVALID_PRCM_PARTITION ||
	       !_prm_bases[part]);
	return __raw_readl(_prm_bases[part] + inst + idx);
}

/* Write into a register in a PRM instance */
void omap4_prminst_write_inst_reg(u32 val, u8 part, s16 inst, u16 idx)
{
	BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
	       part == OMAP4430_INVALID_PRCM_PARTITION ||
	       !_prm_bases[part]);
	__raw_writel(val, _prm_bases[part] + inst + idx);
}

/* Read-modify-write a register in PRM. Caller must lock */
u32 omap4_prminst_rmw_inst_reg_bits(u32 mask, u32 bits, u8 part, s16 inst,
				    u16 idx)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(part, inst, idx);
	v &= ~mask;
	v |= bits;
	omap4_prminst_write_inst_reg(v, part, inst, idx);

	return v;
}

/*
 * Address offset (in bytes) between the reset control and the reset
 * status registers: 4 bytes on OMAP4
 */
#define OMAP4_RST_CTRL_ST_OFFSET		4

/**
 * omap4_prminst_is_hardreset_asserted - read the HW reset line state of
 * submodules contained in the hwmod module
 * @rstctrl_reg: RM_RSTCTRL register address for this module
 * @shift: register bit shift corresponding to the reset line to check
 *
 * Returns 1 if the (sub)module hardreset line is currently asserted,
 * 0 if the (sub)module hardreset line is not currently asserted, or
 * -EINVAL upon parameter error.
 */
int omap4_prminst_is_hardreset_asserted(u8 shift, u8 part, s16 inst,
					u16 rstctrl_offs)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(part, inst, rstctrl_offs);
	v &= 1 << shift;
	v >>= shift;

	return v;
}

/**
 * omap4_prminst_assert_hardreset - assert the HW reset line of a submodule
 * @rstctrl_reg: RM_RSTCTRL register address for this module
 * @shift: register bit shift corresponding to the reset line to assert
 *
 * Some IPs like dsp, ipu or iva contain processors that require an HW
 * reset line to be asserted / deasserted in order to fully enable the
 * IP.  These modules may have multiple hard-reset lines that reset
 * different 'submodules' inside the IP block.  This function will
 * place the submodule into reset.  Returns 0 upon success or -EINVAL
 * upon an argument error.
 */
int omap4_prminst_assert_hardreset(u8 shift, u8 part, s16 inst,
				   u16 rstctrl_offs)
{
	u32 mask = 1 << shift;

	omap4_prminst_rmw_inst_reg_bits(mask, mask, part, inst, rstctrl_offs);

	return 0;
}

/**
 * omap4_prminst_deassert_hardreset - deassert a submodule hardreset line and
 * wait
 * @rstctrl_reg: RM_RSTCTRL register address for this module
 * @shift: register bit shift corresponding to the reset line to deassert
 *
 * Some IPs like dsp, ipu or iva contain processors that require an HW
 * reset line to be asserted / deasserted in order to fully enable the
 * IP.  These modules may have multiple hard-reset lines that reset
 * different 'submodules' inside the IP block.  This function will
 * take the submodule out of reset and wait until the PRCM indicates
 * that the reset has completed before returning.  Returns 0 upon success or
 * -EINVAL upon an argument error, -EEXIST if the submodule was already out
 * of reset, or -EBUSY if the submodule did not exit reset promptly.
 */
int omap4_prminst_deassert_hardreset(u8 shift, u8 part, s16 inst,
				     u16 rstctrl_offs)
{
	int c;
	u32 mask = 1 << shift;
	u16 rstst_offs = rstctrl_offs + OMAP4_RST_CTRL_ST_OFFSET;

	/* Check the current status to avoid de-asserting the line twice */
	if (omap4_prminst_is_hardreset_asserted(shift, part, inst,
						rstctrl_offs) == 0)
		return -EEXIST;

	/* Clear the reset status by writing 1 to the status bit */
	omap4_prminst_rmw_inst_reg_bits(0xffffffff, mask, part, inst,
					rstst_offs);
	/* de-assert the reset control line */
	omap4_prminst_rmw_inst_reg_bits(mask, 0, part, inst, rstctrl_offs);
	/* wait the status to be set */
	omap_test_timeout(omap4_prminst_is_hardreset_asserted(shift, part, inst,
							      rstst_offs),
			  MAX_MODULE_HARDRESET_WAIT, c);

	return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
}


void omap4_prminst_global_warm_sw_reset(void)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
				    OMAP4430_PRM_DEVICE_INST,
				    OMAP4_PRM_RSTCTRL_OFFSET);
	v |= OMAP4430_RST_GLOBAL_WARM_SW_MASK;
	omap4_prminst_write_inst_reg(v, OMAP4430_PRM_PARTITION,
				 OMAP4430_PRM_DEVICE_INST,
				 OMAP4_PRM_RSTCTRL_OFFSET);

	/* OCP barrier */
	v = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
				    OMAP4430_PRM_DEVICE_INST,
				    OMAP4_PRM_RSTCTRL_OFFSET);
}