1// SPDX-License-Identifier: GPL-2.0
2/*
3 * R-Car Generation 2 Power management support
4 *
5 * Copyright (C) 2013 - 2015 Renesas Electronics Corporation
6 * Copyright (C) 2011 Renesas Solutions Corp.
7 * Copyright (C) 2011 Magnus Damm
8 */
9
10#include <linux/kernel.h>
11#include <linux/ioport.h>
12#include <linux/of.h>
13#include <linux/of_address.h>
14#include <linux/smp.h>
15#include <asm/io.h>
16#include <asm/cputype.h>
17#include "common.h"
18#include "rcar-gen2.h"
19
20/* RST */
21#define RST 0xe6160000
22
23#define CA15BAR 0x0020 /* CA15 Boot Address Register */
24#define CA7BAR 0x0030 /* CA7 Boot Address Register */
25#define CA15RESCNT 0x0040 /* CA15 Reset Control Register */
26#define CA7RESCNT 0x0044 /* CA7 Reset Control Register */
27
28/* SYS Boot Address Register */
29#define SBAR_BAREN BIT(4) /* SBAR is valid */
30
31/* Reset Control Registers */
32#define CA15RESCNT_CODE 0xa5a50000
33#define CA15RESCNT_CPUS 0xf /* CPU0-3 */
34#define CA7RESCNT_CODE 0x5a5a0000
35#define CA7RESCNT_CPUS 0xf /* CPU0-3 */
36
37/* On-chip RAM */
38#define ICRAM1 0xe63c0000 /* Inter Connect RAM1 (4 KiB) */
39
40static inline u32 phys_to_sbar(phys_addr_t addr)
41{
42 return (addr >> 8) & 0xfffffc00;
43}
44
45void __init rcar_gen2_pm_init(void)
46{
47 void __iomem *p;
48 u32 bar;
49 struct device_node *np;
50 bool has_a7 = false;
51 bool has_a15 = false;
52 struct resource res;
53 int error;
54
55 if (!request_mem_region(0, SZ_256K, "Boot Area")) {
56 pr_err("Failed to request boot area\n");
57 return;
58 }
59
60 for_each_of_cpu_node(np) {
61 if (of_device_is_compatible(device: np, "arm,cortex-a15"))
62 has_a15 = true;
63 else if (of_device_is_compatible(device: np, "arm,cortex-a7"))
64 has_a7 = true;
65 }
66
67 np = of_find_compatible_node(NULL, NULL, compat: "renesas,smp-sram");
68 if (!np) {
69 /* No smp-sram in DT, fall back to hardcoded address */
70 res = (struct resource)DEFINE_RES_MEM(ICRAM1,
71 shmobile_boot_size);
72 goto map;
73 }
74
75 error = of_address_to_resource(dev: np, index: 0, r: &res);
76 of_node_put(node: np);
77 if (error) {
78 pr_err("Failed to get smp-sram address: %d\n", error);
79 return;
80 }
81
82map:
83 /* RAM for jump stub, because BAR requires 256KB aligned address */
84 if (res.start & (256 * 1024 - 1) ||
85 resource_size(res: &res) < shmobile_boot_size) {
86 pr_err("Invalid smp-sram region\n");
87 return;
88 }
89
90 p = ioremap(offset: res.start, size: resource_size(res: &res));
91 if (!p)
92 return;
93 /*
94 * install the reset vector, use the largest version if we have enough
95 * memory available
96 */
97 if (resource_size(res: &res) >= shmobile_boot_size_gen2) {
98 shmobile_boot_cpu_gen2 = read_cpuid_mpidr();
99 memcpy_toio(p, shmobile_boot_vector_gen2,
100 shmobile_boot_size_gen2);
101 } else {
102 memcpy_toio(p, shmobile_boot_vector, shmobile_boot_size);
103 }
104 iounmap(addr: p);
105
106 /* setup reset vectors */
107 p = ioremap(RST, size: 0x63);
108 bar = phys_to_sbar(addr: res.start);
109 if (has_a15) {
110 writel_relaxed(bar, p + CA15BAR);
111 writel_relaxed(bar | SBAR_BAREN, p + CA15BAR);
112
113 /* de-assert reset for CA15 CPUs */
114 writel_relaxed((readl_relaxed(p + CA15RESCNT) &
115 ~CA15RESCNT_CPUS) | CA15RESCNT_CODE,
116 p + CA15RESCNT);
117 }
118 if (has_a7) {
119 writel_relaxed(bar, p + CA7BAR);
120 writel_relaxed(bar | SBAR_BAREN, p + CA7BAR);
121
122 /* de-assert reset for CA7 CPUs */
123 writel_relaxed((readl_relaxed(p + CA7RESCNT) &
124 ~CA7RESCNT_CPUS) | CA7RESCNT_CODE,
125 p + CA7RESCNT);
126 }
127 iounmap(addr: p);
128
129 shmobile_smp_apmu_suspend_init();
130}
131

source code of linux/arch/arm/mach-shmobile/pm-rcar-gen2.c