Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755145AbZIRQ1e (ORCPT ); Fri, 18 Sep 2009 12:27:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753820AbZIRQ1e (ORCPT ); Fri, 18 Sep 2009 12:27:34 -0400 Received: from caffeine.csclub.uwaterloo.ca ([129.97.134.17]:55193 "EHLO caffeine.csclub.uwaterloo.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752359AbZIRQ1d (ORCPT ); Fri, 18 Sep 2009 12:27:33 -0400 Date: Fri, 18 Sep 2009 12:27:36 -0400 To: linux-kernel@vger.kernel.org Cc: Greg Ungerer , uclinux-dev@uclinux.org, Len Sorensen Subject: [PATCH] Add uboot commandline argument passing support to m68knommu Message-ID: <20090918162736.GY23700@csclub.uwaterloo.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6327 Lines: 206 This patch adds m68knommu support for getting the kernel command line arguments from uboot, including the passing of an initrd image from uboot. We use this on a 5270/5271 based board, and have used it on the 5271evb development board. It is based on a patch found in the linux-2.6-denx git tree, although that tree seems to have had lots of other changes since which are not in the main Linus kernel. I believe this will work on all coldfires, although other m68knommu might be missing the _init_sp stuff in head.S as far as I can tell. I only have the coldfire to test on. Signed-off-by: Lennart Sorensen diff --git a/arch/m68knommu/Kconfig b/arch/m68knommu/Kconfig index e2201b9..064f591 100644 --- a/arch/m68knommu/Kconfig +++ b/arch/m68knommu/Kconfig @@ -533,6 +533,13 @@ config AVNET default y depends on (AVNET5282) +config UBOOT + bool "Support for U-Boot command line parameters" + help + If you say Y here kernel will try to collect command + line parameters from the initial u-boot stack. + default n + config 4KSTACKS bool "Use 4Kb for kernel stacks instead of 8Kb" default y diff --git a/arch/m68knommu/kernel/setup.c b/arch/m68knommu/kernel/setup.c index 5c2bb3e..0e2114e 100644 --- a/arch/m68knommu/kernel/setup.c +++ b/arch/m68knommu/kernel/setup.c @@ -29,6 +29,8 @@ #include #include #include +#include +#include #include #include @@ -52,6 +54,9 @@ void (*mach_reset)(void); void (*mach_halt)(void); void (*mach_power_off)(void); +#if defined(CONFIG_UBOOT) +void parse_uboot_commandline(char *commandp, int size); +#endif #ifdef CONFIG_M68000 #define CPU "MC68000" @@ -128,7 +133,23 @@ void __init setup_arch(char **cmdline_p) #if defined(CONFIG_BOOTPARAM) strncpy(&command_line[0], CONFIG_BOOTPARAM_STRING, sizeof(command_line)); command_line[sizeof(command_line) - 1] = 0; -#endif +#endif /* CONFIG_BOOTPARAM */ + +#if defined(CONFIG_UBOOT) + /* CONFIG_UBOOT and CONFIG_BOOTPARAM defined, concatenate cmdline */ + #if defined(CONFIG_BOOTPARAM) + /* Add the whitespace separator */ + command_line[strlen(CONFIG_BOOTPARAM_STRING)] = ' '; + /* Parse uboot command line into the rest of the buffer */ + parse_uboot_commandline( + &command_line[(strlen(CONFIG_BOOTPARAM_STRING)+1)], + (sizeof(command_line) - (strlen(CONFIG_BOOTPARAM_STRING)+1))); + /* Only CONFIG_UBOOT defined, create cmdline */ + #else + parse_uboot_commandline(&command_line[0], sizeof(command_line)); + #endif /* CONFIG_BOOTPARAM */ + command_line[sizeof(command_line) - 1] = 0; +#endif /* CONFIG_UBOOT */ printk(KERN_INFO "\x0F\r\n\nuClinux/" CPU "\n"); @@ -204,12 +225,82 @@ void __init setup_arch(char **cmdline_p) free_bootmem(memory_start, memory_end - memory_start); reserve_bootmem(memory_start, bootmap_size, BOOTMEM_DEFAULT); +#if defined(CONFIG_UBOOT) && defined(CONFIG_BLK_DEV_INITRD) + if((initrd_start > 0) && (initrd_start < initrd_end) && (initrd_end < memory_end)) { + reserve_bootmem(initrd_start, initrd_end - initrd_start, BOOTMEM_DEFAULT); + } +#endif /* if defined(CONFIG_BLK_DEV_INITRD) */ + /* * Get kmalloc into gear. */ paging_init(); } +#if defined(CONFIG_UBOOT) +/* + * 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: + */ +void 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("initrd at 0x%lx:0x%lx\n", + initrd_start, initrd_end); + } +#endif /* if defined(CONFIG_BLK_DEV_INITRD) */ +} +#endif /* #if defined(CONFIG_UBOOT) */ + /* * Get CPU information for use by the procfs. */ diff --git a/arch/m68knommu/platform/coldfire/head.S b/arch/m68knommu/platform/coldfire/head.S index 2b0d73c..4b91aa2 100644 --- a/arch/m68knommu/platform/coldfire/head.S +++ b/arch/m68knommu/platform/coldfire/head.S @@ -106,6 +106,9 @@ .global _ramvec .global _ramstart .global _ramend +#if defined(CONFIG_UBOOT) +.global _init_sp +#endif /*****************************************************************************/ @@ -124,6 +127,10 @@ _ramstart: .long 0 _ramend: .long 0 +#if defined(CONFIG_UBOOT) +_init_sp: +.long 0 +#endif /*****************************************************************************/ @@ -137,6 +144,9 @@ __HEAD _start: nop /* filler */ movew #0x2700, %sr /* no interrupts */ +#if defined(CONFIG_UBOOT) + movel %sp,_init_sp /* save initial stack pointer */ +#endif /* * Do any platform or board specific setup now. Most boards -- Len Sorensen -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/