1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Common prep/pmac/chrp boot and setup code.
4 */
5
6#include <linux/module.h>
7#include <linux/string.h>
8#include <linux/sched.h>
9#include <linux/init.h>
10#include <linux/kernel.h>
11#include <linux/reboot.h>
12#include <linux/delay.h>
13#include <linux/initrd.h>
14#include <linux/tty.h>
15#include <linux/seq_file.h>
16#include <linux/root_dev.h>
17#include <linux/cpu.h>
18#include <linux/console.h>
19#include <linux/memblock.h>
20#include <linux/export.h>
21#include <linux/nvram.h>
22#include <linux/pgtable.h>
23#include <linux/of_fdt.h>
24#include <linux/irq.h>
25
26#include <asm/io.h>
27#include <asm/processor.h>
28#include <asm/setup.h>
29#include <asm/smp.h>
30#include <asm/elf.h>
31#include <asm/cputable.h>
32#include <asm/bootx.h>
33#include <asm/btext.h>
34#include <asm/machdep.h>
35#include <linux/uaccess.h>
36#include <asm/pmac_feature.h>
37#include <asm/sections.h>
38#include <asm/nvram.h>
39#include <asm/xmon.h>
40#include <asm/time.h>
41#include <asm/serial.h>
42#include <asm/udbg.h>
43#include <asm/text-patching.h>
44#include <asm/cpu_has_feature.h>
45#include <asm/asm-prototypes.h>
46#include <asm/kdump.h>
47#include <asm/feature-fixups.h>
48#include <asm/early_ioremap.h>
49
50#include "setup.h"
51
52#define DBG(fmt...)
53
54extern void bootx_init(unsigned long r4, unsigned long phys);
55
56int boot_cpuid_phys;
57EXPORT_SYMBOL_GPL(boot_cpuid_phys);
58
59int smp_hw_index[NR_CPUS];
60EXPORT_SYMBOL(smp_hw_index);
61
62unsigned int DMA_MODE_READ;
63unsigned int DMA_MODE_WRITE;
64
65EXPORT_SYMBOL(DMA_MODE_READ);
66EXPORT_SYMBOL(DMA_MODE_WRITE);
67
68/*
69 * This is run before start_kernel(), the kernel has been relocated
70 * and we are running with enough of the MMU enabled to have our
71 * proper kernel virtual addresses
72 *
73 * We do the initial parsing of the flat device-tree and prepares
74 * for the MMU to be fully initialized.
75 */
76notrace void __init machine_init(u64 dt_ptr)
77{
78 u32 *addr = (u32 *)patch_site_addr(&patch__memset_nocache);
79 ppc_inst_t insn;
80
81 /* Configure static keys first, now that we're relocated. */
82 setup_feature_keys();
83
84 early_ioremap_init();
85
86 /* Enable early debugging if any specified (see udbg.h) */
87 udbg_early_init();
88
89 patch_instruction_site(&patch__memcpy_nocache, ppc_inst(PPC_RAW_NOP()));
90
91 create_cond_branch(&insn, addr, branch_target(addr), 0x820000);
92 patch_instruction(addr, insn); /* replace b by bne cr0 */
93
94 /* Do some early initialization based on the flat device tree */
95 early_init_devtree(__va(dt_ptr));
96
97 early_init_mmu();
98
99 setup_kdump_trampoline();
100}
101
102/* Checks "l2cr=xxxx" command-line option */
103static int __init ppc_setup_l2cr(char *str)
104{
105 if (cpu_has_feature(CPU_FTR_L2CR)) {
106 unsigned long val = simple_strtoul(str, NULL, 0);
107 printk(KERN_INFO "l2cr set to %lx\n", val);
108 _set_L2CR(0); /* force invalidate by disable cache */
109 _set_L2CR(val); /* and enable it */
110 }
111 return 1;
112}
113__setup("l2cr=", ppc_setup_l2cr);
114
115/* Checks "l3cr=xxxx" command-line option */
116static int __init ppc_setup_l3cr(char *str)
117{
118 if (cpu_has_feature(CPU_FTR_L3CR)) {
119 unsigned long val = simple_strtoul(str, NULL, 0);
120 printk(KERN_INFO "l3cr set to %lx\n", val);
121 _set_L3CR(val); /* and enable it */
122 }
123 return 1;
124}
125__setup("l3cr=", ppc_setup_l3cr);
126
127static int __init ppc_init(void)
128{
129 /* clear the progress line */
130 if (ppc_md.progress)
131 ppc_md.progress(" ", 0xffff);
132
133 /* call platform init */
134 if (ppc_md.init != NULL) {
135 ppc_md.init();
136 }
137 return 0;
138}
139arch_initcall(ppc_init);
140
141static void *__init alloc_stack(void)
142{
143 return memblock_alloc_or_panic(THREAD_SIZE, THREAD_ALIGN);
144}
145
146void __init irqstack_early_init(void)
147{
148 unsigned int i;
149
150 if (IS_ENABLED(CONFIG_VMAP_STACK))
151 return;
152
153 /* interrupt stacks must be in lowmem, we get that for free on ppc32
154 * as the memblock is limited to lowmem by default */
155 for_each_possible_cpu(i) {
156 softirq_ctx[i] = alloc_stack();
157 hardirq_ctx[i] = alloc_stack();
158 }
159}
160
161#ifdef CONFIG_VMAP_STACK
162void *emergency_ctx[NR_CPUS] __ro_after_init = {[0] = &init_stack};
163
164void __init emergency_stack_init(void)
165{
166 unsigned int i;
167
168 for_each_possible_cpu(i)
169 emergency_ctx[i] = alloc_stack();
170}
171#endif
172
173#ifdef CONFIG_BOOKE
174void __init exc_lvl_early_init(void)
175{
176 unsigned int i, hw_cpu;
177
178 /* interrupt stacks must be in lowmem, we get that for free on ppc32
179 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
180 for_each_possible_cpu(i) {
181#ifdef CONFIG_SMP
182 hw_cpu = get_hard_smp_processor_id(i);
183#else
184 hw_cpu = 0;
185#endif
186
187 critirq_ctx[hw_cpu] = alloc_stack();
188#ifdef CONFIG_BOOKE
189 dbgirq_ctx[hw_cpu] = alloc_stack();
190 mcheckirq_ctx[hw_cpu] = alloc_stack();
191#endif
192 }
193}
194#endif
195
196void __init setup_power_save(void)
197{
198#ifdef CONFIG_PPC_BOOK3S_32
199 if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
200 cpu_has_feature(CPU_FTR_CAN_NAP))
201 ppc_md.power_save = ppc6xx_idle;
202#endif
203
204#ifdef CONFIG_PPC_E500
205 if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
206 cpu_has_feature(CPU_FTR_CAN_NAP))
207 ppc_md.power_save = e500_idle;
208#endif
209}
210
211__init void initialize_cache_info(void)
212{
213 /*
214 * Set cache line size based on type of cpu as a default.
215 * Systems with OF can look in the properties on the cpu node(s)
216 * for a possibly more accurate value.
217 */
218 dcache_bsize = cur_cpu_spec->dcache_bsize;
219 icache_bsize = cur_cpu_spec->icache_bsize;
220}
221

source code of linux/arch/powerpc/kernel/setup_32.c