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 "prcm-common.h"
22 #include "prm44xx.h"
23 #include "prm54xx.h"
24 #include "prm7xx.h"
25 #include "prminst44xx.h"
26 #include "prm-regbits-44xx.h"
27 #include "prcm44xx.h"
28 #include "prcm43xx.h"
29 #include "prcm_mpu44xx.h"
30 #include "soc.h"
31 
32 static void __iomem *_prm_bases[OMAP4_MAX_PRCM_PARTITIONS];
33 
34 static s32 prm_dev_inst = PRM_INSTANCE_UNKNOWN;
35 
36 /**
37  * omap_prm_base_init - Populates the prm partitions
38  *
39  * Populates the base addresses of the _prm_bases
40  * array used for read/write of prm module registers.
41  */
42 void omap_prm_base_init(void)
43 {
44 	_prm_bases[OMAP4430_PRM_PARTITION] = prm_base;
45 	_prm_bases[OMAP4430_PRCM_MPU_PARTITION] = prcm_mpu_base;
46 }
47 
48 s32 omap4_prmst_get_prm_dev_inst(void)
49 {
50 	return prm_dev_inst;
51 }
52 
53 void omap4_prminst_set_prm_dev_inst(s32 dev_inst)
54 {
55 	prm_dev_inst = dev_inst;
56 }
57 
58 /* Read a register in a PRM instance */
59 u32 omap4_prminst_read_inst_reg(u8 part, s16 inst, u16 idx)
60 {
61 	BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
62 	       part == OMAP4430_INVALID_PRCM_PARTITION ||
63 	       !_prm_bases[part]);
64 	return readl_relaxed(_prm_bases[part] + inst + idx);
65 }
66 
67 /* Write into a register in a PRM instance */
68 void omap4_prminst_write_inst_reg(u32 val, u8 part, s16 inst, u16 idx)
69 {
70 	BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS ||
71 	       part == OMAP4430_INVALID_PRCM_PARTITION ||
72 	       !_prm_bases[part]);
73 	writel_relaxed(val, _prm_bases[part] + inst + idx);
74 }
75 
76 /* Read-modify-write a register in PRM. Caller must lock */
77 u32 omap4_prminst_rmw_inst_reg_bits(u32 mask, u32 bits, u8 part, s16 inst,
78 				    u16 idx)
79 {
80 	u32 v;
81 
82 	v = omap4_prminst_read_inst_reg(part, inst, idx);
83 	v &= ~mask;
84 	v |= bits;
85 	omap4_prminst_write_inst_reg(v, part, inst, idx);
86 
87 	return v;
88 }
89 
90 /**
91  * omap4_prminst_is_hardreset_asserted - read the HW reset line state of
92  * submodules contained in the hwmod module
93  * @rstctrl_reg: RM_RSTCTRL register address for this module
94  * @shift: register bit shift corresponding to the reset line to check
95  *
96  * Returns 1 if the (sub)module hardreset line is currently asserted,
97  * 0 if the (sub)module hardreset line is not currently asserted, or
98  * -EINVAL upon parameter error.
99  */
100 int omap4_prminst_is_hardreset_asserted(u8 shift, u8 part, s16 inst,
101 					u16 rstctrl_offs)
102 {
103 	u32 v;
104 
105 	v = omap4_prminst_read_inst_reg(part, inst, rstctrl_offs);
106 	v &= 1 << shift;
107 	v >>= shift;
108 
109 	return v;
110 }
111 
112 /**
113  * omap4_prminst_assert_hardreset - assert the HW reset line of a submodule
114  * @rstctrl_reg: RM_RSTCTRL register address for this module
115  * @shift: register bit shift corresponding to the reset line to assert
116  *
117  * Some IPs like dsp, ipu or iva contain processors that require an HW
118  * reset line to be asserted / deasserted in order to fully enable the
119  * IP.  These modules may have multiple hard-reset lines that reset
120  * different 'submodules' inside the IP block.  This function will
121  * place the submodule into reset.  Returns 0 upon success or -EINVAL
122  * upon an argument error.
123  */
124 int omap4_prminst_assert_hardreset(u8 shift, u8 part, s16 inst,
125 				   u16 rstctrl_offs)
126 {
127 	u32 mask = 1 << shift;
128 
129 	omap4_prminst_rmw_inst_reg_bits(mask, mask, part, inst, rstctrl_offs);
130 
131 	return 0;
132 }
133 
134 /**
135  * omap4_prminst_deassert_hardreset - deassert a submodule hardreset line and
136  * wait
137  * @shift: register bit shift corresponding to the reset line to deassert
138  * @st_shift: status bit offset corresponding to the reset line
139  * @part: PRM partition
140  * @inst: PRM instance offset
141  * @rstctrl_offs: reset register offset
142  * @rstst_offs: reset status register offset
143  *
144  * Some IPs like dsp, ipu or iva contain processors that require an HW
145  * reset line to be asserted / deasserted in order to fully enable the
146  * IP.  These modules may have multiple hard-reset lines that reset
147  * different 'submodules' inside the IP block.  This function will
148  * take the submodule out of reset and wait until the PRCM indicates
149  * that the reset has completed before returning.  Returns 0 upon success or
150  * -EINVAL upon an argument error, -EEXIST if the submodule was already out
151  * of reset, or -EBUSY if the submodule did not exit reset promptly.
152  */
153 int omap4_prminst_deassert_hardreset(u8 shift, u8 st_shift, u8 part, s16 inst,
154 				     u16 rstctrl_offs, u16 rstst_offs)
155 {
156 	int c;
157 	u32 mask = 1 << shift;
158 	u32 st_mask = 1 << st_shift;
159 
160 	/* Check the current status to avoid de-asserting the line twice */
161 	if (omap4_prminst_is_hardreset_asserted(shift, part, inst,
162 						rstctrl_offs) == 0)
163 		return -EEXIST;
164 
165 	/* Clear the reset status by writing 1 to the status bit */
166 	omap4_prminst_rmw_inst_reg_bits(0xffffffff, st_mask, part, inst,
167 					rstst_offs);
168 	/* de-assert the reset control line */
169 	omap4_prminst_rmw_inst_reg_bits(mask, 0, part, inst, rstctrl_offs);
170 	/* wait the status to be set */
171 	omap_test_timeout(omap4_prminst_is_hardreset_asserted(st_shift, part,
172 							      inst, rstst_offs),
173 			  MAX_MODULE_HARDRESET_WAIT, c);
174 
175 	return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
176 }
177 
178 
179 void omap4_prminst_global_warm_sw_reset(void)
180 {
181 	u32 v;
182 	s32 inst = omap4_prmst_get_prm_dev_inst();
183 
184 	if (inst == PRM_INSTANCE_UNKNOWN)
185 		return;
186 
187 	v = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION, inst,
188 					OMAP4_PRM_RSTCTRL_OFFSET);
189 	v |= OMAP4430_RST_GLOBAL_WARM_SW_MASK;
190 	omap4_prminst_write_inst_reg(v, OMAP4430_PRM_PARTITION,
191 				 inst, OMAP4_PRM_RSTCTRL_OFFSET);
192 
193 	/* OCP barrier */
194 	v = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
195 				    inst, OMAP4_PRM_RSTCTRL_OFFSET);
196 }
197