[U-Boot] [PATCH v3] regmap: add support for address cell 2

[Kever Yang]

Hi Heiko,


Thanks for your comments.

On 05/05/2017 09:10 PM, Heiko Stuebner wrote:
> Hi Kever,
>
> Am Freitag, 5. Mai 2017, 10:39:35 CEST schrieb Kever Yang:
>> ARM64 is using 64bit address which address cell is 2 instead of 1,
>> update to support it when of-platdata enabled.
>>
>> Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
> This helps make OF_PLATDATA work on my firefly-rk3399 so yay :-),
> but I don't think it's that easy to solve, see below:
>
>> ---
>>
>> Changes in v3:
>> - move of_plat_get_number() into lib/of_plat.c
>>
>> Changes in v2:
>> - rename the fdtdec_get_number() to of_plat_get_number()
>>
>>   drivers/core/regmap.c |  9 +++++++++
>>   include/of_plat.h     | 22 ++++++++++++++++++++++
>>   lib/Makefile          |  3 +++
>>   lib/of_plat.c         | 17 +++++++++++++++++
>>   4 files changed, 51 insertions(+)
>>   create mode 100644 include/of_plat.h
>>   create mode 100644 lib/of_plat.c
>>
>> diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c
>> index 3bec3df..c03279e 100644
>> --- a/drivers/core/regmap.c
>> +++ b/drivers/core/regmap.c
>> @@ -12,6 +12,7 @@
>>   #include <malloc.h>
>>   #include <mapmem.h>
>>   #include <regmap.h>
>> +#include <of_plat.h>
>>   
>>   #include <asm/io.h>
>>   
>> @@ -49,11 +50,19 @@ int regmap_init_mem_platdata(struct udevice *dev, u32 *reg, int count,
>>   	if (!map)
>>   		return -ENOMEM;
>>   
>> +#ifdef CONFIG_PHYS_64BIT
>> +	map->base = of_plat_get_number(reg, 2);
>> +	for (range = map->range; count > 0; reg += 4, range++, count--) {
>> +		range->start = of_plat_get_number(reg, 2);
>> +		range->size = of_plat_get_number(reg + 2, 2);
>> +	}
> I may just be missing something, but how can you be sure that the cell-size
> is always 2?
>
> For example, there were discussions about 64bit platforms not really
> needing to add all the 0x0 elements, when the whole io-registers are well
> below the 4GB mark and for example at least one sunxi also uses this, see
> for example:
> allwinner/sun50i-a64.dtsi, altera/socfpga_stratix10.dtsi,
> broadcom/bcm283x.dtsi and problably more using #address-cells = <1>,
> #size-cells = <1> for their memory mapped io.
>
> And from what I've seen dtoc simply converts the reg property and just
> ignores #address-cells and #size-cells (or I'm overlooking something).
>
> Possible solutions that come to mind would be make dtoc also convert
> #address-cells and #size-cells, making regmap and everybody check it
> or alternatively make dtoc convert regs to cell-size 2 in all cases when
> CONFIG_PHYS_64BIT is set.

@Simon, could you take a look about this issue, I really not good at dtoc
and libfdt, I think maybe we can re-use fdtdec_get_number() if dtoc do not
do the fdt32_to_cpu()  int dtoc?

Thanks,
- Kever
>
>
> Heiko
>
>