arch/mips/rb532/prom.c

Source file repositories/reference/linux-study-clean/arch/mips/rb532/prom.c

File Facts

System
Linux kernel
Corpus path
arch/mips/rb532/prom.c
Extension
.c
Size
2838 bytes
Lines
126
Domain
Architecture Layer
Bucket
arch/mips
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

if (match_tag(prom_argv[i], FREQ_TAG)) {
			idt_cpu_freq = tag2ul(prom_argv[i], FREQ_TAG);
			continue;
		}
#ifdef IGNORE_CMDLINE_MEM
		/* parses out the "mem=xx" arg */
		if (match_tag(prom_argv[i], MEM_TAG))
			continue;
#endif
		if (i > 0)
			*(cp++) = ' ';
		if (match_tag(prom_argv[i], BOARD_TAG)) {
			board = prom_argv[i] + strlen(BOARD_TAG);

			if (match_tag(board, BOARD_RB532A))
				mips_machtype = MACH_MIKROTIK_RB532A;
			else
				mips_machtype = MACH_MIKROTIK_RB532;
		}

		len = strlen(prom_argv[i]);
		memcpy(cp, prom_argv[i], len + 1);
		cp += len;
	}
	*(cp++) = ' ';

	len = strlen(arcs_cmdline);
	if (len > 0) {
		*(cp++) = ' ';
		memcpy(cp, arcs_cmdline, len + 1);
		cp += len;
	}
	cmd_line[COMMAND_LINE_SIZE - 1] = '\0';
	strscpy(arcs_cmdline, cmd_line);
}

void __init prom_init(void)
{
	struct ddr_ram __iomem *ddr;
	phys_addr_t memsize;
	phys_addr_t ddrbase;

	ddr = ioremap(ddr_reg[0].start,
			ddr_reg[0].end - ddr_reg[0].start);

	if (!ddr) {
		printk(KERN_ERR "Unable to remap DDR register\n");
		return;
	}

	ddrbase = (phys_addr_t)&ddr->ddrbase;
	memsize = (phys_addr_t)&ddr->ddrmask;
	memsize = 0 - memsize;

	prom_setup_cmdline();

	/* give all RAM to boot allocator,
	 * except for the first 0x400 and the last 0x200 bytes */
	memblock_add(ddrbase + 0x400, memsize - 0x600);
}

Annotation

Implementation Notes