1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * OMAP2/3 PRM module functions
4 *
5 * Copyright (C) 2010-2011 Texas Instruments, Inc.
6 * Copyright (C) 2010 Nokia Corporation
7 * Benoît Cousson
8 * Paul Walmsley
9 */
10
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/err.h>
14#include <linux/io.h>
15
16#include "powerdomain.h"
17#include "prm2xxx_3xxx.h"
18#include "prm-regbits-24xx.h"
19#include "clockdomain.h"
20
21/**
22 * omap2_prm_is_hardreset_asserted - read the HW reset line state of
23 * submodules contained in the hwmod module
24 * @shift: register bit shift corresponding to the reset line to check
25 * @part: PRM partition, ignored for OMAP2
26 * @prm_mod: PRM submodule base (e.g. CORE_MOD)
27 * @offset: register offset, ignored for OMAP2
28 *
29 * Returns 1 if the (sub)module hardreset line is currently asserted,
30 * 0 if the (sub)module hardreset line is not currently asserted, or
31 * -EINVAL if called while running on a non-OMAP2/3 chip.
32 */
33int omap2_prm_is_hardreset_asserted(u8 shift, u8 part, s16 prm_mod, u16 offset)
34{
35 return omap2_prm_read_mod_bits_shift(domain: prm_mod, OMAP2_RM_RSTCTRL,
36 mask: (1 << shift));
37}
38
39/**
40 * omap2_prm_assert_hardreset - assert the HW reset line of a submodule
41 * @shift: register bit shift corresponding to the reset line to assert
42 * @part: PRM partition, ignored for OMAP2
43 * @prm_mod: PRM submodule base (e.g. CORE_MOD)
44 * @offset: register offset, ignored for OMAP2
45 *
46 * Some IPs like dsp or iva contain processors that require an HW
47 * reset line to be asserted / deasserted in order to fully enable the
48 * IP. These modules may have multiple hard-reset lines that reset
49 * different 'submodules' inside the IP block. This function will
50 * place the submodule into reset. Returns 0 upon success or -EINVAL
51 * upon an argument error.
52 */
53int omap2_prm_assert_hardreset(u8 shift, u8 part, s16 prm_mod, u16 offset)
54{
55 u32 mask;
56
57 mask = 1 << shift;
58 omap2_prm_rmw_mod_reg_bits(mask, bits: mask, module: prm_mod, OMAP2_RM_RSTCTRL);
59
60 return 0;
61}
62
63/**
64 * omap2_prm_deassert_hardreset - deassert a submodule hardreset line and wait
65 * @prm_mod: PRM submodule base (e.g. CORE_MOD)
66 * @rst_shift: register bit shift corresponding to the reset line to deassert
67 * @st_shift: register bit shift for the status of the deasserted submodule
68 * @part: PRM partition, not used for OMAP2
69 * @prm_mod: PRM submodule base (e.g. CORE_MOD)
70 * @rst_offset: reset register offset, not used for OMAP2
71 * @st_offset: reset status register offset, not used for OMAP2
72 *
73 * Some IPs like dsp or iva contain processors that require an HW
74 * reset line to be asserted / deasserted in order to fully enable the
75 * IP. These modules may have multiple hard-reset lines that reset
76 * different 'submodules' inside the IP block. This function will
77 * take the submodule out of reset and wait until the PRCM indicates
78 * that the reset has completed before returning. Returns 0 upon success or
79 * -EINVAL upon an argument error, -EEXIST if the submodule was already out
80 * of reset, or -EBUSY if the submodule did not exit reset promptly.
81 */
82int omap2_prm_deassert_hardreset(u8 rst_shift, u8 st_shift, u8 part,
83 s16 prm_mod, u16 rst_offset, u16 st_offset)
84{
85 u32 rst, st;
86 int c;
87
88 rst = 1 << rst_shift;
89 st = 1 << st_shift;
90
91 /* Check the current status to avoid de-asserting the line twice */
92 if (omap2_prm_read_mod_bits_shift(domain: prm_mod, OMAP2_RM_RSTCTRL, mask: rst) == 0)
93 return -EEXIST;
94
95 /* Clear the reset status by writing 1 to the status bit */
96 omap2_prm_rmw_mod_reg_bits(mask: 0xffffffff, bits: st, module: prm_mod, OMAP2_RM_RSTST);
97 /* de-assert the reset control line */
98 omap2_prm_rmw_mod_reg_bits(mask: rst, bits: 0, module: prm_mod, OMAP2_RM_RSTCTRL);
99 /* wait the status to be set */
100 omap_test_timeout(omap2_prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTST,
101 st),
102 MAX_MODULE_HARDRESET_WAIT, c);
103
104 return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
105}
106
107
108/* Powerdomain low-level functions */
109
110/* Common functions across OMAP2 and OMAP3 */
111int omap2_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank,
112 u8 pwrst)
113{
114 u32 m;
115
116 m = omap2_pwrdm_get_mem_bank_onstate_mask(bank);
117
118 omap2_prm_rmw_mod_reg_bits(mask: m, bits: (pwrst << __ffs(m)), module: pwrdm->prcm_offs,
119 OMAP2_PM_PWSTCTRL);
120
121 return 0;
122}
123
124int omap2_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank,
125 u8 pwrst)
126{
127 u32 m;
128
129 m = omap2_pwrdm_get_mem_bank_retst_mask(bank);
130
131 omap2_prm_rmw_mod_reg_bits(mask: m, bits: (pwrst << __ffs(m)), module: pwrdm->prcm_offs,
132 OMAP2_PM_PWSTCTRL);
133
134 return 0;
135}
136
137int omap2_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
138{
139 u32 m;
140
141 m = omap2_pwrdm_get_mem_bank_stst_mask(bank);
142
143 return omap2_prm_read_mod_bits_shift(domain: pwrdm->prcm_offs, OMAP2_PM_PWSTST,
144 mask: m);
145}
146
147int omap2_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
148{
149 u32 m;
150
151 m = omap2_pwrdm_get_mem_bank_retst_mask(bank);
152
153 return omap2_prm_read_mod_bits_shift(domain: pwrdm->prcm_offs,
154 OMAP2_PM_PWSTCTRL, mask: m);
155}
156
157int omap2_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
158{
159 u32 v;
160
161 v = pwrst << __ffs(OMAP_LOGICRETSTATE_MASK);
162 omap2_prm_rmw_mod_reg_bits(OMAP_LOGICRETSTATE_MASK, bits: v, module: pwrdm->prcm_offs,
163 OMAP2_PM_PWSTCTRL);
164
165 return 0;
166}
167
168int omap2_pwrdm_wait_transition(struct powerdomain *pwrdm)
169{
170 u32 c = 0;
171
172 /*
173 * REVISIT: pwrdm_wait_transition() may be better implemented
174 * via a callback and a periodic timer check -- how long do we expect
175 * powerdomain transitions to take?
176 */
177
178 /* XXX Is this udelay() value meaningful? */
179 while ((omap2_prm_read_mod_reg(module: pwrdm->prcm_offs, OMAP2_PM_PWSTST) &
180 OMAP_INTRANSITION_MASK) &&
181 (c++ < PWRDM_TRANSITION_BAILOUT))
182 udelay(1);
183
184 if (c > PWRDM_TRANSITION_BAILOUT) {
185 pr_err("powerdomain: %s: waited too long to complete transition\n",
186 pwrdm->name);
187 return -EAGAIN;
188 }
189
190 pr_debug("powerdomain: completed transition in %d loops\n", c);
191
192 return 0;
193}
194
195int omap2_clkdm_add_wkdep(struct clockdomain *clkdm1,
196 struct clockdomain *clkdm2)
197{
198 omap2_prm_set_mod_reg_bits(bits: (1 << clkdm2->dep_bit),
199 module: clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP);
200 return 0;
201}
202
203int omap2_clkdm_del_wkdep(struct clockdomain *clkdm1,
204 struct clockdomain *clkdm2)
205{
206 omap2_prm_clear_mod_reg_bits(bits: (1 << clkdm2->dep_bit),
207 module: clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP);
208 return 0;
209}
210
211int omap2_clkdm_read_wkdep(struct clockdomain *clkdm1,
212 struct clockdomain *clkdm2)
213{
214 return omap2_prm_read_mod_bits_shift(domain: clkdm1->pwrdm.ptr->prcm_offs,
215 PM_WKDEP, mask: (1 << clkdm2->dep_bit));
216}
217
218/* XXX Caller must hold the clkdm's powerdomain lock */
219int omap2_clkdm_clear_all_wkdeps(struct clockdomain *clkdm)
220{
221 struct clkdm_dep *cd;
222 u32 mask = 0;
223
224 for (cd = clkdm->wkdep_srcs; cd && cd->clkdm_name; cd++) {
225 if (!cd->clkdm)
226 continue; /* only happens if data is erroneous */
227
228 /* PRM accesses are slow, so minimize them */
229 mask |= 1 << cd->clkdm->dep_bit;
230 cd->wkdep_usecount = 0;
231 }
232
233 omap2_prm_clear_mod_reg_bits(bits: mask, module: clkdm->pwrdm.ptr->prcm_offs,
234 PM_WKDEP);
235 return 0;
236}
237
238

source code of linux/arch/arm/mach-omap2/prm2xxx_3xxx.c