ARM的嵌入式Linux移植体验之操作系统

　f.在arch\arm\def-configs目录中增加配置文件

　　g.在arch\arm\kernel\Makefile中增加对S3C2410的支持

no-irq-arch := $(CONFIG_ARCH_INTEGRATOR) $(CONFIG_ARCH_CLPS711X) \ $(CONFIG_FOOTBRIDGE) $(CONFIG_ARCH_EBSA110) \ $(CONFIG_ARCH_SA1100) $(CONFIG_ARCH_CAMELOT) \ $(CONFIG_ARCH_S3C2400) $(CONFIG_ARCH_S3C2410) \ $(CONFIG_ARCH_MX1ADS) $(CONFIG_ARCH_PXA) obj-$(CONFIG_MIZI) += event.o obj-$(CONFIG_APM) += apm2.o

　　h.修改arch/arm/kernel/debug-armv.S文件，在适当的位置增加如下关于S3C2410的代码：

#elif defined(CONFIG_ARCH_S3C2410) .macro addruart,rx mrc p15, 0, \rx, c1, c0 tst \rx, #1 @ MMU enabled ? moveq \rx, #0x50000000 @ physical base address movne \rx, #0xf0000000 @ virtual address .endm .macro senduart,rd,rx str \rd, [\rx, #0x20] @ UTXH .endm .macro waituart,rd,rx .endm .macro busyuart,rd,rx 1001: ldr \rd, [\rx, #0x10] @ read UTRSTAT tst \rd, #1 << 2 @ TX_EMPTY ? beq 1001b .endm

　　i.修改arch/arm/kernel/setup.c文件

　　此文件中的setup_arch非常关键，用来完成与体系结构相关的初始化：

void __init setup_arch(char **cmdline_p) { struct tag *tags = NULL; struct machine_desc *mdesc; char *from = default_command_line; ROOT_DEV = MKDEV(0, 255); setup_processor(); mdesc = setup_machine(machine_arch_type); machine_name = mdesc->name; if (mdesc->soft_reboot) reboot_setup("s"); if (mdesc->param_offset) tags = phys_to_virt(mdesc->param_offset); /* * Do the machine-specific fixups before we parse the * parameters or tags. */ if (mdesc->fixup) mdesc->fixup(mdesc, (struct param_struct *)tags, &from, &meminfo); /* * If we have the old style parameters, convert them to * a tag list before. */ if (tags && tags->hdr.tag != ATAG_CORE) convert_to_tag_list((struct param_struct *)tags, meminfo.nr_banks == 0); if (tags && tags->hdr.tag == ATAG_CORE) parse_tags(tags); if (meminfo.nr_banks == 0) { meminfo.nr_banks = 1; meminfo.bank[0].start = PHYS_OFFSET; meminfo.bank[0].size = MEM_SIZE; } init_mm.start_code = (unsigned long) &_text; init_mm.end_code = (unsigned long) &_etext; init_mm.end_data = (unsigned long) &_edata; init_mm.brk = (unsigned long) &_end; memcpy(saved_command_line, from, COMMAND_LINE_SIZE); saved_command_line[COMMAND_LINE_SIZE-1] = '\0'; parse_cmdline(&meminfo, cmdline_p, from); bootmem_init(&meminfo); paging_init(&meminfo, mdesc); request_standard_resources(&meminfo, mdesc); /* * Set up various architecture-specific pointers */ init_arch_irq = mdesc->init_irq; #ifdef CONFIG_VT #if defined(CONFIG_VGA_CONSOLE) conswitchp = &vga_con; #elif defined(CONFIG_DUMMY_CONSOLE) conswitchp = &dummy_con; #endif #endif }

　　j.修改arch/arm/mm/mm-armv.c文件（arch/arm/mm/目录中的文件完成与ARM相关的MMU处理）

　　修改

init_maps->bufferable = 0;

　　为

init_maps->bufferable = 1;

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