xref: /linux/arch/powerpc/kernel/setup_32.c (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
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/code-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 
54 extern void bootx_init(unsigned long r4, unsigned long phys);
55 
56 int boot_cpuid_phys;
57 EXPORT_SYMBOL_GPL(boot_cpuid_phys);
58 
59 int smp_hw_index[NR_CPUS];
60 EXPORT_SYMBOL(smp_hw_index);
61 
62 unsigned int DMA_MODE_READ;
63 unsigned int DMA_MODE_WRITE;
64 
65 EXPORT_SYMBOL(DMA_MODE_READ);
66 EXPORT_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  */
76 notrace 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 */
103 static 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 */
116 static 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 
127 static 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 }
139 arch_initcall(ppc_init);
140 
141 static void *__init alloc_stack(void)
142 {
143 	void *ptr = memblock_alloc(THREAD_SIZE, THREAD_ALIGN);
144 
145 	if (!ptr)
146 		panic("cannot allocate %d bytes for stack at %pS\n",
147 		      THREAD_SIZE, (void *)_RET_IP_);
148 
149 	return ptr;
150 }
151 
152 void __init irqstack_early_init(void)
153 {
154 	unsigned int i;
155 
156 	if (IS_ENABLED(CONFIG_VMAP_STACK))
157 		return;
158 
159 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
160 	 * as the memblock is limited to lowmem by default */
161 	for_each_possible_cpu(i) {
162 		softirq_ctx[i] = alloc_stack();
163 		hardirq_ctx[i] = alloc_stack();
164 	}
165 }
166 
167 #ifdef CONFIG_VMAP_STACK
168 void *emergency_ctx[NR_CPUS] __ro_after_init = {[0] = &init_stack};
169 
170 void __init emergency_stack_init(void)
171 {
172 	unsigned int i;
173 
174 	for_each_possible_cpu(i)
175 		emergency_ctx[i] = alloc_stack();
176 }
177 #endif
178 
179 #ifdef CONFIG_BOOKE
180 void __init exc_lvl_early_init(void)
181 {
182 	unsigned int i, hw_cpu;
183 
184 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
185 	 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
186 	for_each_possible_cpu(i) {
187 #ifdef CONFIG_SMP
188 		hw_cpu = get_hard_smp_processor_id(i);
189 #else
190 		hw_cpu = 0;
191 #endif
192 
193 		critirq_ctx[hw_cpu] = alloc_stack();
194 #ifdef CONFIG_BOOKE
195 		dbgirq_ctx[hw_cpu] = alloc_stack();
196 		mcheckirq_ctx[hw_cpu] = alloc_stack();
197 #endif
198 	}
199 }
200 #endif
201 
202 void __init setup_power_save(void)
203 {
204 #ifdef CONFIG_PPC_BOOK3S_32
205 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
206 	    cpu_has_feature(CPU_FTR_CAN_NAP))
207 		ppc_md.power_save = ppc6xx_idle;
208 #endif
209 
210 #ifdef CONFIG_PPC_E500
211 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
212 	    cpu_has_feature(CPU_FTR_CAN_NAP))
213 		ppc_md.power_save = e500_idle;
214 #endif
215 }
216 
217 __init void initialize_cache_info(void)
218 {
219 	/*
220 	 * Set cache line size based on type of cpu as a default.
221 	 * Systems with OF can look in the properties on the cpu node(s)
222 	 * for a possibly more accurate value.
223 	 */
224 	dcache_bsize = cur_cpu_spec->dcache_bsize;
225 	icache_bsize = cur_cpu_spec->icache_bsize;
226 }
227