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 "iomap.h"
20#include "common.h"
21#include "prm44xx.h"
22#include "prminst44xx.h"
23#include "prm-regbits-44xx.h"
24#include "prcm44xx.h"
25#include "prcm_mpu44xx.h"
26
27static 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 */
37u32 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 */
47void 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 */
56u32 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 */
85int 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 */
109int 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 */
134int 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
160void 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}
177