[U-Boot] [PATCH V4 1/6] imx: add dummpy cpu type MXC_CPU_MX6QP/DP

[Stefano Babic]

Hi Peng,

On 10/07/2015 10:06, Peng Fan wrote:

>> Anyway, why is it dummy ? It matches a real SOC, only the check is done
>> in another way.
> 
> Just like MXC_CPU_MX6Q and MXC_CPU_MX6D. MXC_CPU_MX6D is a dummy id,
> MXC_CPU_MX6Q is the real id. Same MXC_CPU_MX6QP/DP are also dummy id.

ok, that is what you meant, understood. It is only that value is not
exactly what we read from DIGIPROG register. The title and commit
message let me think that "the cpu type " is dummy, that is it does not
exist, while the CPU-ID is only built with a formula instead of getting
the value from the register.

IMHO it was enough you simply say "add CPU type for 6QP/DP", dropping
the first part of the commit message that is misleading.


> Since I want to print correct CPU info, so I use this way, but not
> change arch/arm/imx-common/cpu.c.

This is ok, agree.


>> Everything fine, but I have not understood this line, please help me.
>> major is the revision number and should be at least 2 for a QP or DP.
>> But you check that it can be >=, that is revision 1.x is accepted as
>> Plus. Or am I wrong ?
> 
> To i.MX6, MAJOR_LOWER is from 0,1,2... maybe larger.
> I have no knowledge whether major_lower with 2,3,4... is also called DQPlus.
> 6QP/DP is major_lower >= 1, major_lower 0 is for 6DQ.

ok, thanks - this is clear now.

> Now ">= 1" can work
> for 6QP/DP, just check "== 1" may not a good idea.
> 
> Is this clear to explain why this patch?

yes, it is ok. I was missing that even major_lower = 1 is a Plus. Fine
with me.

> 
> The reason for this patch is to print correct cpuinfo:
> 
> printf("CPU:   Freescale i.MX%s rev%d.%d",
> 	   get_imx_type((cpurev & 0xFF000) >> 12),
> 	   (cpurev & 0x000F0) >> 4,
> 	   (cpurev & 0x0000F) >> 0);
> 
> As Fabio's comments, should print i.MX6QP 1.0, but i.MX6Q rev2.0.

ok

Apart interpretation of the commit message, patch is ok for me.

Acked-by: Stefano Babic <sbabic at denx.de>

Best regards,
Stefano Babic



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