[U-Boot,v2] spl: net: Add FIT image support over network boot

FIT support in the net boot case is much like the RAM boot case in that
we load our image to "load_addr" and pass a dummy read function into
"spl_load_simple_fit()". As the load address is no longer hard-coded to
the final execution address, RAW image loading will rely on "load_addr"
pointing to the execution address as they should have before.

Signed-off-by: Andrew F. Davis <afd@ti.com>
---

changes from v1:
 - move "spl_net_load_read" into #ifdef block as suggested by Vignesh

 common/spl/spl_net.c | 30 +++++++++++++++++++++++++++---
 1 file changed, 27 insertions(+), 3 deletions(-)

Hi,

On Wednesday 08 February 2017 11:21 PM, Davis, Andrew wrote:
> FIT support in the net boot case is much like the RAM boot case in that
> we load our image to "load_addr" and pass a dummy read function into
> "spl_load_simple_fit()". As the load address is no longer hard-coded to
> the final execution address, RAW image loading will rely on "load_addr"
> pointing to the execution address as they should have before.
> 

[...]

>  #if defined(CONFIG_SPL_ETH_SUPPORT) || defined(CONFIG_SPL_USBETH_SUPPORT)
> +static ulong spl_net_load_read(struct spl_load_info *load, ulong sector,
> +			       ulong count, void *buf)
> +{
> +	debug("%s: sector %lx, count %lx, buf %lx\n",
> +	      __func__, sector, count, (ulong)buf);
> +	memcpy(buf, (void *)(load_addr + sector), count);
> +	return count;
> +}
> +
>  static int spl_net_load_image(struct spl_image_info *spl_image,
>  			      struct spl_boot_device *bootdev)
>  {
> +	struct image_header *header = (struct image_header *)load_addr;
>  	int rv;
>  
>  	env_init();
>  	env_relocate();
>  	setenv("autoload", "yes");
> -	load_addr = CONFIG_SYS_TEXT_BASE - sizeof(struct image_header);

This breaks when FIT image is not used (For example, breaks
am335x_evm_usbspl_defconfig)

Below snippet helps non FIT case:

+       if (!IS_ENABLED(CONFIG_SPL_LOAD_FIT))
+               load_addr = CONFIG_SYS_TEXT_BASE - sizeof(struct
image_header);
+



>  	rv = eth_initialize();
>  	if (rv == 0) {
>  		printf("No Ethernet devices found\n");
> @@ -36,8 +46,22 @@ static int spl_net_load_image(struct spl_image_info *spl_image,
>  		printf("Problem booting with BOOTP\n");
>  		return rv;
>  	}
> -	return spl_parse_image_header(spl_image,
> -				      (struct image_header *)load_addr);
> +
> +	if (IS_ENABLED(CONFIG_SPL_LOAD_FIT) &&
> +	    image_get_magic(header) == FDT_MAGIC) {
> +		struct spl_load_info load;
> +
> +		debug("Found FIT\n");
> +		load.bl_len = 1;
> +		load.read = spl_net_load_read;
> +		rv = spl_load_simple_fit(spl_image, &load, 0, header);
> +	} else {
> +		debug("Legacy image\n");
> +
> +		rv = spl_parse_image_header(spl_image, header);
> +	}
> +
> +	return rv;
>  }
>  #endif
>  
>

On 02/15/2017 05:07 AM, Vignesh R wrote:
> Hi,
> 
> On Wednesday 08 February 2017 11:21 PM, Davis, Andrew wrote:
>> FIT support in the net boot case is much like the RAM boot case in that
>> we load our image to "load_addr" and pass a dummy read function into
>> "spl_load_simple_fit()". As the load address is no longer hard-coded to
>> the final execution address, RAW image loading will rely on "load_addr"
>> pointing to the execution address as they should have before.
>>
> 
> [...]
> 
>>  #if defined(CONFIG_SPL_ETH_SUPPORT) || defined(CONFIG_SPL_USBETH_SUPPORT)
>> +static ulong spl_net_load_read(struct spl_load_info *load, ulong sector,
>> +			       ulong count, void *buf)
>> +{
>> +	debug("%s: sector %lx, count %lx, buf %lx\n",
>> +	      __func__, sector, count, (ulong)buf);
>> +	memcpy(buf, (void *)(load_addr + sector), count);
>> +	return count;
>> +}
>> +
>>  static int spl_net_load_image(struct spl_image_info *spl_image,
>>  			      struct spl_boot_device *bootdev)
>>  {
>> +	struct image_header *header = (struct image_header *)load_addr;
>>  	int rv;
>>  
>>  	env_init();
>>  	env_relocate();
>>  	setenv("autoload", "yes");
>> -	load_addr = CONFIG_SYS_TEXT_BASE - sizeof(struct image_header);
> 
> This breaks when FIT image is not used (For example, breaks
> am335x_evm_usbspl_defconfig)
> 
> Below snippet helps non FIT case:
> 
> +       if (!IS_ENABLED(CONFIG_SPL_LOAD_FIT))
> +               load_addr = CONFIG_SYS_TEXT_BASE - sizeof(struct
> image_header);
> +
> 

This isn't right, it may happen that the image is not a FIT image but
support for FIT loading is till enabled. This will break that case.

It doesn't seem there is a good standard for where to load the image
header before we know what type of image it is.

Andrew

> 
> 
>>  	rv = eth_initialize();
>>  	if (rv == 0) {
>>  		printf("No Ethernet devices found\n");
>> @@ -36,8 +46,22 @@ static int spl_net_load_image(struct spl_image_info *spl_image,
>>  		printf("Problem booting with BOOTP\n");
>>  		return rv;
>>  	}
>> -	return spl_parse_image_header(spl_image,
>> -				      (struct image_header *)load_addr);
>> +
>> +	if (IS_ENABLED(CONFIG_SPL_LOAD_FIT) &&
>> +	    image_get_magic(header) == FDT_MAGIC) {
>> +		struct spl_load_info load;
>> +
>> +		debug("Found FIT\n");
>> +		load.bl_len = 1;
>> +		load.read = spl_net_load_read;
>> +		rv = spl_load_simple_fit(spl_image, &load, 0, header);
>> +	} else {
>> +		debug("Legacy image\n");
>> +
>> +		rv = spl_parse_image_header(spl_image, header);
>> +	}
>> +
>> +	return rv;
>>  }
>>  #endif
>>  
>>
>