xref: /openbmc/linux/arch/powerpc/kernel/setup_32.c (revision 1fa0a7dc)
1 /*
2  * Common prep/pmac/chrp boot and setup code.
3  */
4 
5 #include <linux/module.h>
6 #include <linux/string.h>
7 #include <linux/sched.h>
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/reboot.h>
11 #include <linux/delay.h>
12 #include <linux/initrd.h>
13 #include <linux/tty.h>
14 #include <linux/seq_file.h>
15 #include <linux/root_dev.h>
16 #include <linux/cpu.h>
17 #include <linux/console.h>
18 #include <linux/memblock.h>
19 #include <linux/export.h>
20 #include <linux/nvram.h>
21 
22 #include <asm/io.h>
23 #include <asm/prom.h>
24 #include <asm/processor.h>
25 #include <asm/pgtable.h>
26 #include <asm/setup.h>
27 #include <asm/smp.h>
28 #include <asm/elf.h>
29 #include <asm/cputable.h>
30 #include <asm/bootx.h>
31 #include <asm/btext.h>
32 #include <asm/machdep.h>
33 #include <linux/uaccess.h>
34 #include <asm/pmac_feature.h>
35 #include <asm/sections.h>
36 #include <asm/nvram.h>
37 #include <asm/xmon.h>
38 #include <asm/time.h>
39 #include <asm/serial.h>
40 #include <asm/udbg.h>
41 #include <asm/code-patching.h>
42 #include <asm/cpu_has_feature.h>
43 #include <asm/asm-prototypes.h>
44 #include <asm/kdump.h>
45 #include <asm/feature-fixups.h>
46 
47 #include "setup.h"
48 
49 #define DBG(fmt...)
50 
51 extern void bootx_init(unsigned long r4, unsigned long phys);
52 
53 int boot_cpuid_phys;
54 EXPORT_SYMBOL_GPL(boot_cpuid_phys);
55 
56 int smp_hw_index[NR_CPUS];
57 EXPORT_SYMBOL(smp_hw_index);
58 
59 unsigned long ISA_DMA_THRESHOLD;
60 unsigned int DMA_MODE_READ;
61 unsigned int DMA_MODE_WRITE;
62 
63 EXPORT_SYMBOL(DMA_MODE_READ);
64 EXPORT_SYMBOL(DMA_MODE_WRITE);
65 
66 /*
67  * This is run before start_kernel(), the kernel has been relocated
68  * and we are running with enough of the MMU enabled to have our
69  * proper kernel virtual addresses
70  *
71  * We do the initial parsing of the flat device-tree and prepares
72  * for the MMU to be fully initialized.
73  */
74 notrace void __init machine_init(u64 dt_ptr)
75 {
76 	unsigned int *addr = (unsigned int *)patch_site_addr(&patch__memset_nocache);
77 	unsigned long insn;
78 
79 	/* Configure static keys first, now that we're relocated. */
80 	setup_feature_keys();
81 
82 	/* Enable early debugging if any specified (see udbg.h) */
83 	udbg_early_init();
84 
85 	patch_instruction_site(&patch__memcpy_nocache, PPC_INST_NOP);
86 
87 	insn = create_cond_branch(addr, branch_target(addr), 0x820000);
88 	patch_instruction(addr, insn);	/* replace b by bne cr0 */
89 
90 	/* Do some early initialization based on the flat device tree */
91 	early_init_devtree(__va(dt_ptr));
92 
93 	early_init_mmu();
94 
95 	setup_kdump_trampoline();
96 }
97 
98 /* Checks "l2cr=xxxx" command-line option */
99 static int __init ppc_setup_l2cr(char *str)
100 {
101 	if (cpu_has_feature(CPU_FTR_L2CR)) {
102 		unsigned long val = simple_strtoul(str, NULL, 0);
103 		printk(KERN_INFO "l2cr set to %lx\n", val);
104 		_set_L2CR(0);		/* force invalidate by disable cache */
105 		_set_L2CR(val);		/* and enable it */
106 	}
107 	return 1;
108 }
109 __setup("l2cr=", ppc_setup_l2cr);
110 
111 /* Checks "l3cr=xxxx" command-line option */
112 static int __init ppc_setup_l3cr(char *str)
113 {
114 	if (cpu_has_feature(CPU_FTR_L3CR)) {
115 		unsigned long val = simple_strtoul(str, NULL, 0);
116 		printk(KERN_INFO "l3cr set to %lx\n", val);
117 		_set_L3CR(val);		/* and enable it */
118 	}
119 	return 1;
120 }
121 __setup("l3cr=", ppc_setup_l3cr);
122 
123 static int __init ppc_init(void)
124 {
125 	/* clear the progress line */
126 	if (ppc_md.progress)
127 		ppc_md.progress("             ", 0xffff);
128 
129 	/* call platform init */
130 	if (ppc_md.init != NULL) {
131 		ppc_md.init();
132 	}
133 	return 0;
134 }
135 arch_initcall(ppc_init);
136 
137 static void *__init alloc_stack(void)
138 {
139 	void *ptr = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
140 
141 	if (!ptr)
142 		panic("cannot allocate %d bytes for stack at %pS\n",
143 		      THREAD_SIZE, (void *)_RET_IP_);
144 
145 	return ptr;
146 }
147 
148 void __init irqstack_early_init(void)
149 {
150 	unsigned int i;
151 
152 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
153 	 * as the memblock is limited to lowmem by default */
154 	for_each_possible_cpu(i) {
155 		softirq_ctx[i] = alloc_stack();
156 		hardirq_ctx[i] = alloc_stack();
157 	}
158 }
159 
160 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
161 void __init exc_lvl_early_init(void)
162 {
163 	unsigned int i, hw_cpu;
164 
165 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
166 	 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
167 	for_each_possible_cpu(i) {
168 #ifdef CONFIG_SMP
169 		hw_cpu = get_hard_smp_processor_id(i);
170 #else
171 		hw_cpu = 0;
172 #endif
173 
174 		critirq_ctx[hw_cpu] = alloc_stack();
175 #ifdef CONFIG_BOOKE
176 		dbgirq_ctx[hw_cpu] = alloc_stack();
177 		mcheckirq_ctx[hw_cpu] = alloc_stack();
178 #endif
179 	}
180 }
181 #endif
182 
183 void __init setup_power_save(void)
184 {
185 #ifdef CONFIG_PPC_BOOK3S_32
186 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
187 	    cpu_has_feature(CPU_FTR_CAN_NAP))
188 		ppc_md.power_save = ppc6xx_idle;
189 #endif
190 
191 #ifdef CONFIG_E500
192 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
193 	    cpu_has_feature(CPU_FTR_CAN_NAP))
194 		ppc_md.power_save = e500_idle;
195 #endif
196 }
197 
198 __init void initialize_cache_info(void)
199 {
200 	/*
201 	 * Set cache line size based on type of cpu as a default.
202 	 * Systems with OF can look in the properties on the cpu node(s)
203 	 * for a possibly more accurate value.
204 	 */
205 	dcache_bsize = cur_cpu_spec->dcache_bsize;
206 	icache_bsize = cur_cpu_spec->icache_bsize;
207 	ucache_bsize = 0;
208 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
209 		ucache_bsize = icache_bsize = dcache_bsize;
210 }
211