arch/unicore32/kernel/setup.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * linux/arch/unicore32/kernel/setup.c
   4  *
   5  * Code specific to PKUnity SoC and UniCore ISA
   6  *
   7  * Copyright (C) 2001-2010 GUAN Xue-tao
   8  */
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <linux/stddef.h>
  12 #include <linux/ioport.h>
  13 #include <linux/delay.h>
  14 #include <linux/utsname.h>
  15 #include <linux/initrd.h>
  16 #include <linux/console.h>
  17 #include <linux/memblock.h>
  18 #include <linux/seq_file.h>
  19 #include <linux/screen_info.h>
  20 #include <linux/init.h>
  21 #include <linux/root_dev.h>
  22 #include <linux/cpu.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/smp.h>
  25 #include <linux/fs.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/elf.h>
  28 #include <linux/io.h>
  29
  30 #include <asm/cputype.h>
  31 #include <asm/sections.h>
  32 #include <asm/setup.h>
  33 #include <asm/cacheflush.h>
  34 #include <asm/tlbflush.h>
  35 #include <asm/traps.h>
  36 #include <asm/memblock.h>
  37
  38 #include "setup.h"
  39
  40 #ifndef MEM_SIZE
  41 #define MEM_SIZE        (16*1024*1024)
  42 #endif
  43
  44 struct stack {
  45         u32 irq[3];
  46         u32 abt[3];
  47         u32 und[3];
  48 } ____cacheline_aligned;
  49
  50 static struct stack stacks[NR_CPUS];
  51
  52 #ifdef CONFIG_VGA_CONSOLE
  53 struct screen_info screen_info;
  54 #endif
  55
  56 char elf_platform[ELF_PLATFORM_SIZE];
  57 EXPORT_SYMBOL(elf_platform);
  58
  59 static char __initdata cmd_line[COMMAND_LINE_SIZE];
  60
  61 static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
  62
  63 /*
  64  * Standard memory resources
  65  */
  66 static struct resource mem_res[] = {
  67         {
  68                 .name = "Kernel code",
  69                 .start = 0,
  70                 .end = 0,
  71                 .flags = IORESOURCE_SYSTEM_RAM
  72         },
  73         {
  74                 .name = "Kernel data",
  75                 .start = 0,
  76                 .end = 0,
  77                 .flags = IORESOURCE_SYSTEM_RAM
  78         }
  79 };
  80
  81 #define kernel_code mem_res[0]
  82 #define kernel_data mem_res[1]
  83
  84 /*
  85  * These functions re-use the assembly code in head.S, which
  86  * already provide the required functionality.
  87  */
  88 static void __init setup_processor(void)
  89 {
  90         printk(KERN_DEFAULT "CPU: UniCore-II [%08x] revision %d, cr=%08lx\n",
  91                uc32_cpuid, (int)(uc32_cpuid >> 16) & 15, cr_alignment);
  92
  93         sprintf(init_utsname()->machine, "puv3");
  94         sprintf(elf_platform, "ucv2");
  95 }
  96
  97 /*
  98  * cpu_init - initialise one CPU.
  99  *
 100  * cpu_init sets up the per-CPU stacks.
 101  */
 102 void cpu_init(void)
 103 {
 104         unsigned int cpu = smp_processor_id();
 105         struct stack *stk = &stacks[cpu];
 106
 107         /*
 108          * setup stacks for re-entrant exception handlers
 109          */
 110         __asm__ (
 111         "mov.a  asr, %1\n\t"
 112         "add    sp, %0, %2\n\t"
 113         "mov.a  asr, %3\n\t"
 114         "add    sp, %0, %4\n\t"
 115         "mov.a  asr, %5\n\t"
 116         "add    sp, %0, %6\n\t"
 117         "mov.a  asr, %7"
 118             :
 119             : "r" (stk),
 120               "r" (PSR_R_BIT | PSR_I_BIT | INTR_MODE),
 121               "I" (offsetof(struct stack, irq[0])),
 122               "r" (PSR_R_BIT | PSR_I_BIT | ABRT_MODE),
 123               "I" (offsetof(struct stack, abt[0])),
 124               "r" (PSR_R_BIT | PSR_I_BIT | EXTN_MODE),
 125               "I" (offsetof(struct stack, und[0])),
 126               "r" (PSR_R_BIT | PSR_I_BIT | PRIV_MODE)
 127         : "r30", "cc");
 128 }
 129
 130 static int __init uc32_add_memory(unsigned long start, unsigned long size)
 131 {
 132         struct membank *bank = &meminfo.bank[meminfo.nr_banks];
 133
 134         if (meminfo.nr_banks >= NR_BANKS) {
 135                 printk(KERN_CRIT "NR_BANKS too low, "
 136                         "ignoring memory at %#lx\n", start);
 137                 return -EINVAL;
 138         }
 139
 140         /*
 141          * Ensure that start/size are aligned to a page boundary.
 142          * Size is appropriately rounded down, start is rounded up.
 143          */
 144         size -= start & ~PAGE_MASK;
 145
 146         bank->start = PAGE_ALIGN(start);
 147         bank->size  = size & PAGE_MASK;
 148
 149         /*
 150          * Check whether this memory region has non-zero size or
 151          * invalid node number.
 152          */
 153         if (bank->size == 0)
 154                 return -EINVAL;
 155
 156         meminfo.nr_banks++;
 157         return 0;
 158 }
 159
 160 /*
 161  * Pick out the memory size.  We look for mem=size@start,
 162  * where start and size are "size[KkMm]"
 163  */
 164 static int __init early_mem(char *p)
 165 {
 166         static int usermem __initdata = 1;
 167         unsigned long size, start;
 168         char *endp;
 169
 170         /*
 171          * If the user specifies memory size, we
 172          * blow away any automatically generated
 173          * size.
 174          */
 175         if (usermem) {
 176                 usermem = 0;
 177                 meminfo.nr_banks = 0;
 178         }
 179
 180         start = PHYS_OFFSET;
 181         size  = memparse(p, &endp);
 182         if (*endp == '@')
 183                 start = memparse(endp + 1, NULL);
 184
 185         uc32_add_memory(start, size);
 186
 187         return 0;
 188 }
 189 early_param("mem", early_mem);
 190
 191 static void __init
 192 request_standard_resources(struct meminfo *mi)
 193 {
 194         struct resource *res;
 195         int i;
 196
 197         kernel_code.start   = virt_to_phys(_stext);
 198         kernel_code.end     = virt_to_phys(_etext - 1);
 199         kernel_data.start   = virt_to_phys(_sdata);
 200         kernel_data.end     = virt_to_phys(_end - 1);
 201
 202         for (i = 0; i < mi->nr_banks; i++) {
 203                 if (mi->bank[i].size == 0)
 204                         continue;
 205
 206                 res = memblock_alloc_low(sizeof(*res), SMP_CACHE_BYTES);
 207                 if (!res)
 208                         panic("%s: Failed to allocate %zu bytes align=%x\n",
 209                               __func__, sizeof(*res), SMP_CACHE_BYTES);
 210
 211                 res->name  = "System RAM";
 212                 res->start = mi->bank[i].start;
 213                 res->end   = mi->bank[i].start + mi->bank[i].size - 1;
 214                 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 215
 216                 request_resource(&iomem_resource, res);
 217
 218                 if (kernel_code.start >= res->start &&
 219                     kernel_code.end <= res->end)
 220                         request_resource(res, &kernel_code);
 221                 if (kernel_data.start >= res->start &&
 222                     kernel_data.end <= res->end)
 223                         request_resource(res, &kernel_data);
 224         }
 225 }
 226
 227 static void (*init_machine)(void) __initdata;
 228
 229 static int __init customize_machine(void)
 230 {
 231         /* customizes platform devices, or adds new ones */
 232         if (init_machine)
 233                 init_machine();
 234         return 0;
 235 }
 236 arch_initcall(customize_machine);
 237
 238 void __init setup_arch(char **cmdline_p)
 239 {
 240         char *from = default_command_line;
 241
 242         setup_processor();
 243
 244         init_mm.start_code = (unsigned long) _stext;
 245         init_mm.end_code   = (unsigned long) _etext;
 246         init_mm.end_data   = (unsigned long) _edata;
 247         init_mm.brk        = (unsigned long) _end;
 248
 249         /* parse_early_param needs a boot_command_line */
 250         strlcpy(boot_command_line, from, COMMAND_LINE_SIZE);
 251
 252         /* populate cmd_line too for later use, preserving boot_command_line */
 253         strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
 254         *cmdline_p = cmd_line;
 255
 256         parse_early_param();
 257
 258         uc32_memblock_init(&meminfo);
 259
 260         paging_init();
 261         request_standard_resources(&meminfo);
 262
 263         cpu_init();
 264
 265         /*
 266          * Set up various architecture-specific pointers
 267          */
 268         init_machine = puv3_core_init;
 269
 270 #ifdef CONFIG_VT
 271 #if defined(CONFIG_VGA_CONSOLE)
 272         conswitchp = &vga_con;
 273 #endif
 274 #endif
 275         early_trap_init();
 276 }
 277
 278 static struct cpu cpuinfo_unicore;
 279
 280 static int __init topology_init(void)
 281 {
 282         int i;
 283
 284         for_each_possible_cpu(i)
 285                 register_cpu(&cpuinfo_unicore, i);
 286
 287         return 0;
 288 }
 289 subsys_initcall(topology_init);
 290
 291 #ifdef CONFIG_HAVE_PROC_CPU
 292 static int __init proc_cpu_init(void)
 293 {
 294         struct proc_dir_entry *res;
 295
 296         res = proc_mkdir("cpu", NULL);
 297         if (!res)
 298                 return -ENOMEM;
 299         return 0;
 300 }
 301 fs_initcall(proc_cpu_init);
 302 #endif
 303
 304 static int c_show(struct seq_file *m, void *v)
 305 {
 306         seq_printf(m, "Processor\t: UniCore-II rev %d (%s)\n",
 307                    (int)(uc32_cpuid >> 16) & 15, elf_platform);
 308
 309         seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
 310                    loops_per_jiffy / (500000/HZ),
 311                    (loops_per_jiffy / (5000/HZ)) % 100);
 312
 313         /* dump out the processor features */
 314         seq_puts(m, "Features\t: CMOV UC-F64");
 315
 316         seq_printf(m, "\nCPU implementer\t: 0x%02x\n", uc32_cpuid >> 24);
 317         seq_printf(m, "CPU architecture: 2\n");
 318         seq_printf(m, "CPU revision\t: %d\n", (uc32_cpuid >> 16) & 15);
 319
 320         seq_printf(m, "Cache type\t: write-back\n"
 321                         "Cache clean\t: cp0 c5 ops\n"
 322                         "Cache lockdown\t: not support\n"
 323                         "Cache format\t: Harvard\n");
 324
 325         seq_puts(m, "\n");
 326
 327         seq_printf(m, "Hardware\t: PKUnity v3\n");
 328
 329         return 0;
 330 }
 331
 332 static void *c_start(struct seq_file *m, loff_t *pos)
 333 {
 334         return *pos < 1 ? (void *)1 : NULL;
 335 }
 336
 337 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 338 {
 339         ++*pos;
 340         return NULL;
 341 }
 342
 343 static void c_stop(struct seq_file *m, void *v)
 344 {
 345 }
 346
 347 const struct seq_operations cpuinfo_op = {
 348         .start  = c_start,
 349         .next   = c_next,
 350         .stop   = c_stop,
 351         .show   = c_show
 352 };