[U-Boot] [PATCH v6 2/2] armv8: fsl-layerscape: Make DDR non secure in MMU tables

[Hou Zhiqiang]

> -----Original Message-----
> From: York Sun [mailto:yorksun at freescale.com]
> Sent: 2015年12月3日 11:05
> To: Hou Zhiqiang-B48286; U-Boot Mailing List
> Cc: Pan Lijun-B44306; Hu Mingkai-B21284; Sharma Bhupesh-B45370; Gong
> Qianyu-B52263; Tom Rini; Li Yang-Leo-R58472; Albert Aribaud; Kushwaha
> Prabhakar-B32579; Wang Huan-B18965
> Subject: Re: [PATCH v6 2/2] armv8: fsl-layerscape: Make DDR non secure in
> MMU tables
> 
> 
> 
> On 12/02/2015 06:48 PM, Hou Zhiqiang-B48286 wrote:
> >
> >
> >> -----Original Message-----
> >> From: York Sun [mailto:yorksun at freescale.com]
> >> Sent: 2015年12月3日 0:00
> >> To: Hou Zhiqiang-B48286; U-Boot Mailing List
> >> Cc: Pan Lijun-B44306; Hu Mingkai-B21284; Sharma Bhupesh-B45370; Gong
> >> Qianyu-B52263; Tom Rini; Li Yang-Leo-R58472; Albert Aribaud; Kushwaha
> >> Prabhakar-B32579; Wang Huan-B18965
> >> Subject: Re: [PATCH v6 2/2] armv8: fsl-layerscape: Make DDR non
> >> secure in MMU tables
> >>
> >>
> >>
> >> On 12/01/2015 10:38 PM, Hou Zhiqiang-B48286 wrote:
> >>
> >> <snip>
> >>
> >>>>  	/* Invalidate all table entries */
> >>>>  	memset(level0_table, 0, PGTABLE_SIZE); @@ -269,6 +344,22 @@
> >>>> static inline void final_mmu_setup(void)
> >>>>  			       &final_mmu_table[i]);
> >>>>  		}
> >>>>  	}
> >>>> +	/* Set the secure memory to secure in MMU */ #ifdef
> >>>> +CONFIG_SYS_MEM_RESERVE_SECURE
> >>>> +	if (gd->secure_ram & MEM_RESERVE_SECURE_MAINTAINED) { #ifdef
> >>>> +CONFIG_FSL_LSCH3
> >>>> +		level2_table_secure = level2_table1 + 512; #elif
> >>>> +defined(CONFIG_FSL_LSCH2)
> >>>> +		level2_table_secure = level2_table2 + 512; #endif
> >>>> +		/* update tlb pointer */
> >>>> +		gd->arch.tlb_addr = gd->secure_ram & ~0x3;
> >>>
> >>> The memory reserved for mmu table was lost? If it's better to record
> >>> it
> >> and use for non-sec mmu table?
> >>
> >> That can be arranged.
> >>
> >>>
> >>> If this func is called from non-secure state, for example EL2, the
> >> secure memory cannot be accessed and the PMD_SECT_NS bit should be
> >> cleared.
> >>
> >> We need to setup secure memory at EL3 to have secure memory to begin
> with.
> >> But you have a point here. Will look into it.
> >>
> >
> > Yes, this func is called at EL3 for now, it is a assumption for this
> func.
> > I mean we'd better make it a API that can be invoked at both EL3 and
> > EL2 to setup the MMU table. And do you know if the EL1 should be taken
> > into account in u-boot?
> 
> We don't need to differentiate this function for EL2 or EL1 if we ever
> need to run at. The only difference is EL3 can handle secure access. So
> adding a detection of exception level before setting secure bit will
> suffice.

ok.

Thanks,
Zhiqiang