/arch/powerpc/kernel/setup_32.c

  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
 23#include <asm/io.h>
 24#include <asm/prom.h>
 25#include <asm/processor.h>
 26#include <asm/pgtable.h>
 27#include <asm/setup.h>
 28#include <asm/smp.h>
 29#include <asm/elf.h>
 30#include <asm/cputable.h>
 31#include <asm/bootx.h>
 32#include <asm/btext.h>
 33#include <asm/machdep.h>
 34#include <linux/uaccess.h>
 35#include <asm/pmac_feature.h>
 36#include <asm/sections.h>
 37#include <asm/nvram.h>
 38#include <asm/xmon.h>
 39#include <asm/time.h>
 40#include <asm/serial.h>
 41#include <asm/udbg.h>
 42#include <asm/code-patching.h>
 43#include <asm/cpu_has_feature.h>
 44#include <asm/asm-prototypes.h>
 45#include <asm/kdump.h>
 46#include <asm/feature-fixups.h>
 47#include <asm/early_ioremap.h>
 48
 49#include "setup.h"
 50
 51#define DBG(fmt...)
 52
 53extern void bootx_init(unsigned long r4, unsigned long phys);
 54
 55int boot_cpuid_phys;
 56EXPORT_SYMBOL_GPL(boot_cpuid_phys);
 57
 58int smp_hw_index[NR_CPUS];
 59EXPORT_SYMBOL(smp_hw_index);
 60
 61unsigned int DMA_MODE_READ;
 62unsigned int DMA_MODE_WRITE;
 63
 64EXPORT_SYMBOL(DMA_MODE_READ);
 65EXPORT_SYMBOL(DMA_MODE_WRITE);
 66
 67/*
 68 * This is run before start_kernel(), the kernel has been relocated
 69 * and we are running with enough of the MMU enabled to have our
 70 * proper kernel virtual addresses
 71 *
 72 * We do the initial parsing of the flat device-tree and prepares
 73 * for the MMU to be fully initialized.
 74 */
 75notrace void __init machine_init(u64 dt_ptr)
 76{
 77	unsigned int *addr = (unsigned int *)patch_site_addr(&patch__memset_nocache);
 78	unsigned long insn;
 79
 80	/* Configure static keys first, now that we're relocated. */
 81	setup_feature_keys();
 82
 83	early_ioremap_setup();
 84
 85	/* Enable early debugging if any specified (see udbg.h) */
 86	udbg_early_init();
 87
 88	patch_instruction_site(&patch__memcpy_nocache, PPC_INST_NOP);
 89
 90	insn = create_cond_branch(addr, branch_target(addr), 0x820000);
 91	patch_instruction(addr, insn);	/* replace b by bne cr0 */
 92
 93	/* Do some early initialization based on the flat device tree */
 94	early_init_devtree(__va(dt_ptr));
 95
 96	early_init_mmu();
 97
 98	setup_kdump_trampoline();
 99}
100
101/* Checks "l2cr=xxxx" command-line option */
102static int __init ppc_setup_l2cr(char *str)
103{
104	if (cpu_has_feature(CPU_FTR_L2CR)) {
105		unsigned long val = simple_strtoul(str, NULL, 0);
106		printk(KERN_INFO "l2cr set to %lx\n", val);
107		_set_L2CR(0);		/* force invalidate by disable cache */
108		_set_L2CR(val);		/* and enable it */
109	}
110	return 1;
111}
112__setup("l2cr=", ppc_setup_l2cr);
113
114/* Checks "l3cr=xxxx" command-line option */
115static int __init ppc_setup_l3cr(char *str)
116{
117	if (cpu_has_feature(CPU_FTR_L3CR)) {
118		unsigned long val = simple_strtoul(str, NULL, 0);
119		printk(KERN_INFO "l3cr set to %lx\n", val);
120		_set_L3CR(val);		/* and enable it */
121	}
122	return 1;
123}
124__setup("l3cr=", ppc_setup_l3cr);
125
126static int __init ppc_init(void)
127{
128	/* clear the progress line */
129	if (ppc_md.progress)
130		ppc_md.progress("             ", 0xffff);
131
132	/* call platform init */
133	if (ppc_md.init != NULL) {
134		ppc_md.init();
135	}
136	return 0;
137}
138arch_initcall(ppc_init);
139
140static void *__init alloc_stack(void)
141{
142	void *ptr = memblock_alloc(THREAD_SIZE, THREAD_ALIGN);
143
144	if (!ptr)
145		panic("cannot allocate %d bytes for stack at %pS\n",
146		      THREAD_SIZE, (void *)_RET_IP_);
147
148	return ptr;
149}
150
151void __init irqstack_early_init(void)
152{
153	unsigned int i;
154
155	if (IS_ENABLED(CONFIG_VMAP_STACK))
156		return;
157
158	/* interrupt stacks must be in lowmem, we get that for free on ppc32
159	 * as the memblock is limited to lowmem by default */
160	for_each_possible_cpu(i) {
161		softirq_ctx[i] = alloc_stack();
162		hardirq_ctx[i] = alloc_stack();
163	}
164}
165
166#ifdef CONFIG_VMAP_STACK
167void *emergency_ctx[NR_CPUS] __ro_after_init;
168
169void __init emergency_stack_init(void)
170{
171	unsigned int i;
172
173	for_each_possible_cpu(i)
174		emergency_ctx[i] = alloc_stack();
175}
176#endif
177
178#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
179void __init exc_lvl_early_init(void)
180{
181	unsigned int i, hw_cpu;
182
183	/* interrupt stacks must be in lowmem, we get that for free on ppc32
184	 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
185	for_each_possible_cpu(i) {
186#ifdef CONFIG_SMP
187		hw_cpu = get_hard_smp_processor_id(i);
188#else
189		hw_cpu = 0;
190#endif
191
192		critirq_ctx[hw_cpu] = alloc_stack();
193#ifdef CONFIG_BOOKE
194		dbgirq_ctx[hw_cpu] = alloc_stack();
195		mcheckirq_ctx[hw_cpu] = alloc_stack();
196#endif
197	}
198}
199#endif
200
201void __init setup_power_save(void)
202{
203#ifdef CONFIG_PPC_BOOK3S_32
204	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
205	    cpu_has_feature(CPU_FTR_CAN_NAP))
206		ppc_md.power_save = ppc6xx_idle;
207#endif
208
209#ifdef CONFIG_E500
210	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
211	    cpu_has_feature(CPU_FTR_CAN_NAP))
212		ppc_md.power_save = e500_idle;
213#endif
214}
215
216__init void initialize_cache_info(void)
217{
218	/*
219	 * Set cache line size based on type of cpu as a default.
220	 * Systems with OF can look in the properties on the cpu node(s)
221	 * for a possibly more accurate value.
222	 */
223	dcache_bsize = cur_cpu_spec->dcache_bsize;
224	icache_bsize = cur_cpu_spec->icache_bsize;
225	ucache_bsize = 0;
226	if (IS_ENABLED(CONFIG_PPC_BOOK3S_601) || IS_ENABLED(CONFIG_E200))
227		ucache_bsize = icache_bsize = dcache_bsize;
228}