[PATCH v4] mtd: cfi: respect reg address length

[Stefan Roese]

On 5/11/23 13:19, Nuno Sá wrote:
> flash_get_size() will get the flash size from the device itself and go
> through all erase regions to read protection status. However, the device
> mappable region (eg: devicetree reg property) might be lower than the
> device full size which means that the above cycle will result in a data
> bus exception. This change fixes it by reading the 'addr_size' during
> probe() and also use that as one possible upper limit.
> 
> Signed-off-by: Nuno Sá <nuno.sa at analog.com>

Applied to u-boot-cfi-flash/master

Thanks,
Stefan

> ---
> 
> v2:
>   * Fix compilation when CONFIG_CFI_FLASH is not set. Done by redefining
> cfi_flash_bank_size() when CONFIG_CFI_FLASH is set (by returning dts
> size).
>      
> v3:
>   * Fix another compilation warning by explicitly casting to unsigned
> long in cfi_flash_bank_size()
>      
> v4:
>   * Made CI tests pass. Done by going back to the basic v1 patch and
> making sure we have proper guards for CONFIG_CFI_FLASH and the proper
> casts when needed.
>   * Dropped second patch.
> 
> Alright, Stefan, I think now it's ready to go. All checks passed for me
> in github [1]. Apparently, I needed to go back to version 1 (with proper
> fixes) which adds the reg size check without changing any previous
> functionality. I cannot say for sure but seems some platforms are
> relying on cfi_flash_bank_size() and that cannot be overwritten to
> return reg_size. Also dropped the second patch as (I think) it would
> only be meaningful to have it if also converting flash_info_t:size which
> would be a fairly bigger change...
>      
> [1]: https://github.com/u-boot/u-boot/pull/281
> 
>   drivers/mtd/cfi_flash.c | 10 +++++++++-
>   include/flash.h         |  1 +
>   2 files changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
> index f378f6fb6139..8ade7949a68e 100644
> --- a/drivers/mtd/cfi_flash.c
> +++ b/drivers/mtd/cfi_flash.c
> @@ -2196,6 +2196,12 @@ ulong flash_get_size(phys_addr_t base, int banknum)
>   		/* multiply the size by the number of chips */
>   		info->size *= size_ratio;
>   		max_size = cfi_flash_bank_size(banknum);
> +#ifdef CONFIG_CFI_FLASH
> +		if (max_size)
> +			max_size = min((unsigned long)info->addr_size, max_size);
> +		else
> +			max_size = info->addr_size;
> +#endif
>   		if (max_size && info->size > max_size) {
>   			debug("[truncated from %ldMiB]", info->size >> 20);
>   			info->size = max_size;
> @@ -2492,15 +2498,17 @@ unsigned long flash_init(void)
>   static int cfi_flash_probe(struct udevice *dev)
>   {
>   	fdt_addr_t addr;
> +	fdt_size_t size;
>   	int idx;
>   
>   	for (idx = 0; idx < CFI_MAX_FLASH_BANKS; idx++) {
> -		addr = dev_read_addr_index(dev, idx);
> +		addr = dev_read_addr_size_index(dev, idx, &size);
>   		if (addr == FDT_ADDR_T_NONE)
>   			break;
>   
>   		flash_info[cfi_flash_num_flash_banks].dev = dev;
>   		flash_info[cfi_flash_num_flash_banks].base = addr;
> +		flash_info[cfi_flash_num_flash_banks].addr_size = size;
>   		cfi_flash_num_flash_banks++;
>   	}
>   	gd->bd->bi_flashstart = flash_info[0].base;
> diff --git a/include/flash.h b/include/flash.h
> index 95992fa689bb..3710a2731b76 100644
> --- a/include/flash.h
> +++ b/include/flash.h
> @@ -46,6 +46,7 @@ typedef struct {
>   #ifdef CONFIG_CFI_FLASH			/* DM-specific parts */
>   	struct udevice *dev;
>   	phys_addr_t base;
> +	phys_size_t addr_size;
>   #endif
>   } flash_info_t;
>   

Viele Grüße,
Stefan Roese

-- 
DENX Software Engineering GmbH,      Managing Director: Erika Unter
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr at denx.de