[PATCH v5 05/11] spl: Convert mmc to spl_load

[Sean Anderson]

On 8/3/23 04:31, Xavier Drudis Ferran wrote:
> El Mon, Jul 31, 2023 at 06:42:57PM -0400, Sean Anderson deia:
>> This converts the mmc loader to spl_load. Legacy images are handled by
>> spl_load (via spl_parse_image_header), so mmc_load_legacy can be
>> omitted.
>>
> 
> Yes. I haven't used the legacy case, but by looking at the code, it
> seems to me that mmc_load_legacy left the image at some mapped memory
> at [ spl_image->load_addr,   spl_image->load_addr + size )
> and the new code does too, but when the image is not aligned, the
> memory that gets written to
> was at [ spl_image->load_addr,   spl_image->load_addr + size + spl_image->offset % mmc->read_bl_len )
> and it will
> be at [ spl_image->load_addr - spl_image->offset % mmc->read_bl_len,   spl_image->load_addr + size )
> after this patch.
> 
> Meaning both with or without this patch some memory outside the image
> gets written when the image is not aligned on media, but before it was
> some part of a block at the end and now is that part before the
> beginning.
> 
> Whether that's better or worse I don't know. It depends on whether
> it's a problem to write in non mapped memory, whether there's
> something worth preserving there, and whether some SOC has some sort
> of special behaving memory just there, like it happened with the issue
> Jerome Forissier found (note in this case it wasn't legacy, it was
> simple fit)

Fundamentally, we can't really deal with unaligned images without a
bounce-buffer. The method used by SPL_LOAD_FIT_IMAGE_BUFFER_SIZE will
continue working, since we call into the FIT routines to load the image.
I would like to defer bounce buffering for other images until someone
actually needs it.

Note that in the FIT case, you can also do `mkimage -EB`, at least if
you aren't using FIT_LOAD_FULL.

--Sean

> https://cas5-0-urlprotect.trendmicro.com:443/wis/clicktime/v1/query?url=https%3a%2f%2fpatchwork.ozlabs.org%2fproject%2fuboot%2fpatch%2fc941d835a85255ff81a21c72069c3a9fc9a8a255.1656489154.git.jerome.forissier%40linaro.org%2f&umid=1ca400c8-7d50-4ae9-9abc-31dac6468719&auth=d807158c60b7d2502abde8a2fc01f40662980862-09f1f8fbc507564d04c74bc07523f5da694b0761
>                                                                   
>> Signed-off-by: Sean Anderson <sean.anderson at seco.com>
>> ---
>> 
>> Changes in v5:
>> - Rework to load header in spl_load
>> 
>>  common/spl/spl_mmc.c | 91 ++++----------------------------------------
>>  1 file changed, 8 insertions(+), 83 deletions(-)
>> 
>> diff --git a/common/spl/spl_mmc.c b/common/spl/spl_mmc.c
>> index a665091b00..c926a42c0f 100644
>> --- a/common/spl/spl_mmc.c
>> +++ b/common/spl/spl_mmc.c
>> @@ -17,48 +17,6 @@
>>  #include <mmc.h>
>>  #include <image.h>
>>  
>> -static int mmc_load_legacy(struct spl_image_info *spl_image,
>> -			   struct spl_boot_device *bootdev,
>> -			   struct mmc *mmc,
>> -			   ulong sector, struct legacy_img_hdr *header)
>> -{
>> -	u32 image_offset_sectors;
>> -	u32 image_size_sectors;
>> -	unsigned long count;
>> -	u32 image_offset;
>> -	int ret;
>> -
>> -	ret = spl_parse_image_header(spl_image, bootdev, header);
>> -	if (ret)
>> -		return ret;
>> -
>> -	/* convert offset to sectors - round down */
>> -	image_offset_sectors = spl_image->offset / mmc->read_bl_len;
>> -	/* calculate remaining offset */
>> -	image_offset = spl_image->offset % mmc->read_bl_len;
>> -
>> -	/* convert size to sectors - round up */
>> -	image_size_sectors = (spl_image->size + mmc->read_bl_len - 1) /
>> -			     mmc->read_bl_len;
>> -
>> -	/* Read the header too to avoid extra memcpy */
>> -	count = blk_dread(mmc_get_blk_desc(mmc),
>> -			  sector + image_offset_sectors,
>> -			  image_size_sectors,
>> -			  (void *)(ulong)spl_image->load_addr);
>> -	debug("read %x sectors to %lx\n", image_size_sectors,
>> -	      spl_image->load_addr);
>> -	if (count != image_size_sectors)
>> -		return -EIO;
>> -
>> -	if (image_offset)
>> -		memmove((void *)(ulong)spl_image->load_addr,
>> -			(void *)(ulong)spl_image->load_addr + image_offset,
>> -			spl_image->size);
>> -
>> -	return 0;
>> -}
>> -
>>  static ulong h_spl_load_read(struct spl_load_info *load, ulong sector,
>>  			     ulong count, void *buf)
>>  {
>> @@ -82,47 +40,14 @@ int mmc_load_image_raw_sector(struct spl_image_info *spl_image,
>>  			      struct spl_boot_device *bootdev,
>>  			      struct mmc *mmc, unsigned long sector)
>>  {
>> -	unsigned long count;
>> -	struct legacy_img_hdr *header;
>> -	struct blk_desc *bd = mmc_get_blk_desc(mmc);
>> -	int ret = 0;
>> -
>> -	header = spl_get_load_buffer(-sizeof(*header), bd->blksz);
>> -
>> -	/* read image header to find the image size & load address */
>> -	count = blk_dread(bd, sector, 1, header);
>> -	debug("hdr read sector %lx, count=%lu\n", sector, count);
>> -	if (count == 0) {
>> -		ret = -EIO;
>> -		goto end;
>> -	}
>> -
>> -	if (IS_ENABLED(CONFIG_SPL_LOAD_FIT) &&
>> -	    image_get_magic(header) == FDT_MAGIC) {
>> -		struct spl_load_info load;
>> -
>> -		debug("Found FIT\n");
>> -		load.dev = mmc;
>> -		load.priv = NULL;
>> -		load.filename = NULL;
>> -		load.bl_len = mmc->read_bl_len;
>> -		load.read = h_spl_load_read;
>> -		ret = spl_load_simple_fit(spl_image, &load, sector, header);
>> -	} else if (IS_ENABLED(CONFIG_SPL_LOAD_IMX_CONTAINER)) {
>> -		struct spl_load_info load;
>> -
>> -		load.dev = mmc;
>> -		load.priv = NULL;
>> -		load.filename = NULL;
>> -		load.bl_len = mmc->read_bl_len;
>> -		load.read = h_spl_load_read;
>> -
>> -		ret = spl_load_imx_container(spl_image, &load, sector);
>> -	} else {
>> -		ret = mmc_load_legacy(spl_image, bootdev, mmc, sector, header);
>> -	}
>> -
>> -end:
>> +	int ret;
>> +	struct spl_load_info load = {
>> +		.dev = mmc,
>> +		.bl_len = mmc->read_bl_len,
>> +		.read = h_spl_load_read,
>> +	};
>> +
>> +	ret = spl_load(spl_image, bootdev, &load, 0, sector);
>>  	if (ret) {
>>  #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
>>  		puts("mmc_load_image_raw_sector: mmc block read error\n");
>> -- 
>> 2.40.1
>>