1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright 2011 Freescale Semiconductor, Inc.
4 * Copyright 2011 Linaro Ltd.
5 */
6
7#include <linux/init.h>
8#include <linux/io.h>
9#include <linux/iopoll.h>
10#include <linux/of.h>
11#include <linux/of_address.h>
12#include <linux/platform_device.h>
13#include <linux/reset-controller.h>
14#include <linux/smp.h>
15#include <asm/smp_plat.h>
16#include "common.h"
17#include "hardware.h"
18
19#define SRC_SCR 0x000
20#define SRC_GPR1_V1 0x020
21#define SRC_GPR1_V2 0x074
22#define SRC_GPR1(gpr_v2) ((gpr_v2) ? SRC_GPR1_V2 : SRC_GPR1_V1)
23#define BP_SRC_SCR_WARM_RESET_ENABLE 0
24#define BP_SRC_SCR_SW_GPU_RST 1
25#define BP_SRC_SCR_SW_VPU_RST 2
26#define BP_SRC_SCR_SW_IPU1_RST 3
27#define BP_SRC_SCR_SW_OPEN_VG_RST 4
28#define BP_SRC_SCR_SW_IPU2_RST 12
29#define BP_SRC_SCR_CORE1_RST 14
30#define BP_SRC_SCR_CORE1_ENABLE 22
31/* below is for i.MX7D */
32#define SRC_A7RCR1 0x008
33#define BP_SRC_A7RCR1_A7_CORE1_ENABLE 1
34#define GPC_CPU_PGC_SW_PUP_REQ 0xf0
35#define GPC_CPU_PGC_SW_PDN_REQ 0xfc
36#define GPC_PGC_C1 0x840
37#define BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7 0x2
38
39static void __iomem *src_base;
40static DEFINE_SPINLOCK(scr_lock);
41static bool gpr_v2;
42static void __iomem *gpc_base;
43
44static const int sw_reset_bits[5] = {
45 BP_SRC_SCR_SW_GPU_RST,
46 BP_SRC_SCR_SW_VPU_RST,
47 BP_SRC_SCR_SW_IPU1_RST,
48 BP_SRC_SCR_SW_OPEN_VG_RST,
49 BP_SRC_SCR_SW_IPU2_RST
50};
51
52static int imx_src_reset_module(struct reset_controller_dev *rcdev,
53 unsigned long sw_reset_idx)
54{
55 unsigned long timeout;
56 unsigned long flags;
57 int bit;
58 u32 val;
59
60 if (sw_reset_idx >= ARRAY_SIZE(sw_reset_bits))
61 return -EINVAL;
62
63 bit = 1 << sw_reset_bits[sw_reset_idx];
64
65 spin_lock_irqsave(&scr_lock, flags);
66 val = readl_relaxed(src_base + SRC_SCR);
67 val |= bit;
68 writel_relaxed(val, src_base + SRC_SCR);
69 spin_unlock_irqrestore(lock: &scr_lock, flags);
70
71 timeout = jiffies + msecs_to_jiffies(m: 1000);
72 while (readl(addr: src_base + SRC_SCR) & bit) {
73 if (time_after(jiffies, timeout))
74 return -ETIME;
75 cpu_relax();
76 }
77
78 return 0;
79}
80
81static const struct reset_control_ops imx_src_ops = {
82 .reset = imx_src_reset_module,
83};
84
85static void imx_gpcv2_set_m_core_pgc(bool enable, u32 offset)
86{
87 writel_relaxed(enable, gpc_base + offset);
88}
89
90/*
91 * The motivation for bringing up the second i.MX7D core inside the kernel
92 * is that legacy vendor bootloaders usually do not implement PSCI support.
93 * This is a significant blocker for systems in the field that are running old
94 * bootloader versions to upgrade to a modern mainline kernel version, as only
95 * one CPU of the i.MX7D would be brought up.
96 * Bring up the second i.MX7D core inside the kernel to make the migration
97 * path to mainline kernel easier for the existing iMX7D users.
98 */
99void imx_gpcv2_set_core1_pdn_pup_by_software(bool pdn)
100{
101 u32 reg = pdn ? GPC_CPU_PGC_SW_PDN_REQ : GPC_CPU_PGC_SW_PUP_REQ;
102 u32 val, pup;
103 int ret;
104
105 imx_gpcv2_set_m_core_pgc(enable: true, GPC_PGC_C1);
106 val = readl_relaxed(gpc_base + reg);
107 val |= BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7;
108 writel_relaxed(val, gpc_base + reg);
109
110 ret = readl_relaxed_poll_timeout_atomic(gpc_base + reg, pup,
111 !(pup & BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7),
112 5, 1000000);
113 if (ret < 0) {
114 pr_err("i.MX7D: CORE1_A7 power up timeout\n");
115 val &= ~BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7;
116 writel_relaxed(val, gpc_base + reg);
117 }
118
119 imx_gpcv2_set_m_core_pgc(enable: false, GPC_PGC_C1);
120}
121
122void imx_enable_cpu(int cpu, bool enable)
123{
124 u32 mask, val;
125
126 cpu = cpu_logical_map(cpu);
127 spin_lock(lock: &scr_lock);
128 if (gpr_v2) {
129 if (enable)
130 imx_gpcv2_set_core1_pdn_pup_by_software(pdn: false);
131
132 mask = 1 << (BP_SRC_A7RCR1_A7_CORE1_ENABLE + cpu - 1);
133 val = readl_relaxed(src_base + SRC_A7RCR1);
134 val = enable ? val | mask : val & ~mask;
135 writel_relaxed(val, src_base + SRC_A7RCR1);
136 } else {
137 mask = 1 << (BP_SRC_SCR_CORE1_ENABLE + cpu - 1);
138 val = readl_relaxed(src_base + SRC_SCR);
139 val = enable ? val | mask : val & ~mask;
140 val |= 1 << (BP_SRC_SCR_CORE1_RST + cpu - 1);
141 writel_relaxed(val, src_base + SRC_SCR);
142 }
143 spin_unlock(lock: &scr_lock);
144}
145
146void imx_set_cpu_jump(int cpu, void *jump_addr)
147{
148 cpu = cpu_logical_map(cpu);
149 writel_relaxed(__pa_symbol(jump_addr),
150 src_base + SRC_GPR1(gpr_v2) + cpu * 8);
151}
152
153u32 imx_get_cpu_arg(int cpu)
154{
155 cpu = cpu_logical_map(cpu);
156 return readl_relaxed(src_base + SRC_GPR1(gpr_v2) + cpu * 8 + 4);
157}
158
159void imx_set_cpu_arg(int cpu, u32 arg)
160{
161 cpu = cpu_logical_map(cpu);
162 writel_relaxed(arg, src_base + SRC_GPR1(gpr_v2) + cpu * 8 + 4);
163}
164
165void __init imx_src_init(void)
166{
167 struct device_node *np;
168 u32 val;
169
170 np = of_find_compatible_node(NULL, NULL, compat: "fsl,imx51-src");
171 if (!np)
172 return;
173 src_base = of_iomap(node: np, index: 0);
174 WARN_ON(!src_base);
175
176 /*
177 * force warm reset sources to generate cold reset
178 * for a more reliable restart
179 */
180 spin_lock(lock: &scr_lock);
181 val = readl_relaxed(src_base + SRC_SCR);
182 val &= ~(1 << BP_SRC_SCR_WARM_RESET_ENABLE);
183 writel_relaxed(val, src_base + SRC_SCR);
184 spin_unlock(lock: &scr_lock);
185}
186
187void __init imx7_src_init(void)
188{
189 struct device_node *np;
190
191 gpr_v2 = true;
192
193 np = of_find_compatible_node(NULL, NULL, compat: "fsl,imx7d-src");
194 if (!np)
195 return;
196
197 src_base = of_iomap(node: np, index: 0);
198 if (!src_base)
199 return;
200
201 np = of_find_compatible_node(NULL, NULL, compat: "fsl,imx7d-gpc");
202 if (!np)
203 return;
204
205 gpc_base = of_iomap(node: np, index: 0);
206 if (!gpc_base)
207 return;
208}
209
210static const struct of_device_id imx_src_dt_ids[] = {
211 { .compatible = "fsl,imx51-src" },
212 { /* sentinel */ }
213};
214
215static int imx_src_probe(struct platform_device *pdev)
216{
217 struct reset_controller_dev *rcdev;
218
219 rcdev = devm_kzalloc(dev: &pdev->dev, size: sizeof(*rcdev), GFP_KERNEL);
220 if (!rcdev)
221 return -ENOMEM;
222
223 rcdev->ops = &imx_src_ops;
224 rcdev->dev = &pdev->dev;
225 rcdev->of_node = pdev->dev.of_node;
226 rcdev->nr_resets = ARRAY_SIZE(sw_reset_bits);
227
228 return devm_reset_controller_register(dev: &pdev->dev, rcdev);
229}
230
231static struct platform_driver imx_src_driver = {
232 .driver = {
233 .name = "imx-src",
234 .of_match_table = imx_src_dt_ids,
235 },
236 .probe = imx_src_probe,
237};
238builtin_platform_driver(imx_src_driver);
239

source code of linux/arch/arm/mach-imx/src.c