diff options
author | Greg Ungerer <gerg@linux-m68k.org> | 2016-09-05 08:23:50 +0300 |
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committer | Greg Ungerer <gerg@linux-m68k.org> | 2016-09-26 05:02:59 +0300 |
commit | aa5ac789bd96c7a6628a8167de562fa660f1f481 (patch) | |
tree | 3cba478fe5cc7c0eec6154dda3d37e7aa7bf77c7 /arch/m68k/kernel/uboot.c | |
parent | 2a744007c332f9d604b95aaecb106596c52ab001 (diff) | |
download | linux-aa5ac789bd96c7a6628a8167de562fa660f1f481.tar.xz |
m68k: generalize uboot command line support
The uboot command line support needs to be used by both MMU and no-MMU
setups, but currently we only have the code in the no-MMU code paths.
Move the uboot command line processing code into its own file. Add
appropriate calls to it from both the MMU and no-MMU arch setup code.
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diffstat (limited to 'arch/m68k/kernel/uboot.c')
-rw-r--r-- | arch/m68k/kernel/uboot.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/arch/m68k/kernel/uboot.c b/arch/m68k/kernel/uboot.c new file mode 100644 index 000000000000..b3536a82a262 --- /dev/null +++ b/arch/m68k/kernel/uboot.c @@ -0,0 +1,107 @@ +/* + * uboot.c -- uboot arguments support + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/fb.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/console.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/bootmem.h> +#include <linux/seq_file.h> +#include <linux/init.h> +#include <linux/initrd.h> +#include <linux/root_dev.h> +#include <linux/rtc.h> + +#include <asm/setup.h> +#include <asm/irq.h> +#include <asm/machdep.h> +#include <asm/pgtable.h> +#include <asm/sections.h> + +/* + * parse_uboot_commandline + * + * Copies u-boot commandline arguments and store them in the proper linux + * variables. + * + * Assumes: + * _init_sp global contains the address in the stack pointer when the + * kernel starts (see head.S::_start) + * + * U-Boot calling convention: + * (*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end); + * + * _init_sp can be parsed as such + * + * _init_sp+00 = u-boot cmd after jsr into kernel (skip) + * _init_sp+04 = &kernel board_info (residual data) + * _init_sp+08 = &initrd_start + * _init_sp+12 = &initrd_end + * _init_sp+16 = &cmd_start + * _init_sp+20 = &cmd_end + * + * This also assumes that the memory locations pointed to are still + * unmodified. U-boot places them near the end of external SDRAM. + * + * Argument(s): + * commandp = the linux commandline arg container to fill. + * size = the sizeof commandp. + * + * Returns: + */ +static void __init parse_uboot_commandline(char *commandp, int size) +{ + extern unsigned long _init_sp; + unsigned long *sp; + unsigned long uboot_kbd; + unsigned long uboot_initrd_start, uboot_initrd_end; + unsigned long uboot_cmd_start, uboot_cmd_end; + + sp = (unsigned long *)_init_sp; + uboot_kbd = sp[1]; + uboot_initrd_start = sp[2]; + uboot_initrd_end = sp[3]; + uboot_cmd_start = sp[4]; + uboot_cmd_end = sp[5]; + + if (uboot_cmd_start && uboot_cmd_end) + strncpy(commandp, (const char *)uboot_cmd_start, size); +#if defined(CONFIG_BLK_DEV_INITRD) + if (uboot_initrd_start && uboot_initrd_end && + (uboot_initrd_end > uboot_initrd_start)) { + initrd_start = uboot_initrd_start; + initrd_end = uboot_initrd_end; + ROOT_DEV = Root_RAM0; + printk(KERN_INFO "initrd at 0x%lx:0x%lx\n", + initrd_start, initrd_end); + } +#endif /* if defined(CONFIG_BLK_DEV_INITRD) */ +} + +__init void process_uboot_commandline(char *commandp, int size) +{ + int len, n; + + n = strnlen(commandp, size); + commandp += n; + len = size - n; + if (len) { + /* Add the whitespace separator */ + *commandp++ = ' '; + len--; + } + + parse_uboot_commandline(commandp, len); + commandp[size - 1] = 0; +} |