Re: [PATCH v2] kexec: pass initrd position in dtb

[Wang Nan <wangnan0@huawei.com>]

On 2014/3/20 13:57, Dave Young wrote:
> On 03/20/14 at 01:35pm, Wang Nan wrote:
>> This patch append the position of initrd to dtb when loading arm kernel
>> and initrd without using atag.
>>
>> Change from v1:
>>
>>  - Remove #include "libfdt_internal.h" since it is for internal use
>>    for libfdt.
>>
>> Signed-off-by: Wang Nan <wangnan0@huawei.com>
>> Cc: Simon Horman <horms@verge.net.au>
>> Cc: Dave Young <dyoung@redhat.com>
>> Cc: Geng Hui <hui.geng@huawei.com>
>> ---
>>  kexec/arch/arm/kexec-zImage-arm.c | 83 +++++++++++++++++++++++++++------------
>>  1 file changed, 58 insertions(+), 25 deletions(-)
>>
>> diff --git a/kexec/arch/arm/kexec-zImage-arm.c b/kexec/arch/arm/kexec-zImage-arm.c
>> index 8a35018..1cd4ed0 100644
>> --- a/kexec/arch/arm/kexec-zImage-arm.c
>> +++ b/kexec/arch/arm/kexec-zImage-arm.c
>> @@ -216,6 +216,47 @@ int atag_arm_load(struct kexec_info *info, unsigned long base,
>>  	return 0;
>>  }
>>  
>> +static int setup_dtb_prop(char **bufp, off_t *sizep, const char *node_name,
>> +		const char *prop_name, const void *val, int len)
>> +{
>> +	char *dtb_buf;
>> +	int off;
>> +
>> +	if ((bufp == NULL) || (sizep == NULL) || (*bufp == NULL))
>> +		die("Internal error\n");
>> +
>> +	dtb_buf = *bufp;
>> +
>> +	*sizep = fdt_totalsize(*bufp) + FDT_TAGSIZE + len +
>> +		_ALIGN(strlen(node_name) + 1, FDT_TAGSIZE) +
>> +		_ALIGN(strlen(prop_name) + 1, FDT_TAGSIZE) +
>> +		sizeof(struct fdt_property);
>> +
>> +	dtb_buf = xrealloc(dtb_buf, *sizep);
>> +	if (dtb_buf == NULL)
>> +		die("xrealloc failed\n");
>> +	*bufp = dtb_buf;
>> +
>> +	fdt_set_totalsize(dtb_buf, *sizep);
>> +
>> +	/* check if the subnode already exists */
>> +	off = fdt_path_offset(dtb_buf, node_name);
>> +
>> +	if (off == -FDT_ERR_NOTFOUND)
>> +		off = fdt_add_subnode(dtb_buf, off, node_name);
>> +	if (off < 0) {
>> +		fprintf(stderr, "FDT: Error adding %s node.\n", node_name);
>> +		return -1;
>> +	}
>> +	if (fdt_setprop(dtb_buf, off, prop_name,
>> +				val, len) != 0) {
>> +		fprintf(stderr, "FDT: Error setting %s/%s property.\n",
>> +				node_name, prop_name);
>> +		return -1;
>> +	}
>> +	return 0;
>> +}
>> +
>>  int zImage_arm_load(int argc, char **argv, const char *buf, off_t len,
>>  	struct kexec_info *info)
>>  {
>> @@ -375,32 +416,11 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len,
>>  			}
>>  
>>  			if (command_line) {
>> -				const char *node_name = "/chosen";
>> -				const char *prop_name = "bootargs";
>> -				int off;
>> -
>> -				dtb_length = fdt_totalsize(dtb_buf) + 1024 +
>> -					strlen(command_line);
>> -				dtb_buf = xrealloc(dtb_buf, dtb_length);
>> -				fdt_set_totalsize(dtb_buf, dtb_length);
>> -
>> -				/* check if a /choosen subnode already exists */
>> -				off = fdt_path_offset(dtb_buf, node_name);
>> -
>> -				if (off == -FDT_ERR_NOTFOUND)
>> -					off = fdt_add_subnode(dtb_buf, off, node_name);
>> -
>> -				if (off < 0) {
>> -					fprintf(stderr, "FDT: Error adding %s node.\n", node_name);
>> +				/* Error should have been reported */
>> +				if (setup_dtb_prop(&dtb_buf, &dtb_length, "/chosen",
>> +						"bootargs", command_line,
>> +						strlen(command_line) + 1))
>>  					return -1;
>> -				}
>> -
>> -				if (fdt_setprop(dtb_buf, off, prop_name,
>> -						command_line, strlen(command_line) + 1) != 0) {
>> -					fprintf(stderr, "FDT: Error setting %s/%s property.\n",
>> -						node_name, prop_name);
>> -					return -1;
>> -				}
>>  			}
>>  		} else {
>>  			/*
>> @@ -417,6 +437,19 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len,
>>  		if (ramdisk) {
>>  			add_segment(info, ramdisk_buf, initrd_size,
>>  			            initrd_base, initrd_size);
>> +
>> +			unsigned long start, end;
>> +			start = cpu_to_be32((unsigned long)(initrd_base));
>> +			end = cpu_to_be32((unsigned long)(initrd_base + initrd_size));
>> +
>> +			if (setup_dtb_prop(&dtb_buf, &dtb_length, "/chosen",
>> +					"linux,initrd-start", &start,
>> +					sizeof(start)))
>> +				return -1;
>> +			if (setup_dtb_prop(&dtb_buf, &dtb_length, "/chosen",
>> +					"linux,initrd-end", &end,
>> +					sizeof(end)))
>> +				return -1;
>>  		}
>>  
>>  		/* Stick the dtb at the end of the initrd and page
>> -- 
>> 1.8.4
>>
> 
> Hi,
> 
> Thanks for quick update, would you like to redo the patch again and
> split it to 2 patches as I mentioned in another reply?
> 

So you still prefer to use FDT_TAGALIGN?

No problem.

> Thanks
> Dave
> 



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