Re: [PATCH 02/10] ARM: Layerscape: LS1028a: reserve DDR region for TF-A

[Sascha Hauer <s.hauer@pengutronix.de>]

On Tue, Jan 09, 2024 at 10:37:15AM +0100, Ahmad Fatoum wrote:
> On 09.01.24 10:15, Sascha Hauer wrote:
> > On LS1028a the TF-A is placed in DDR, so we have to reserve the region
> > in order to keep Linux away from it.
> > 
> > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> > ---
> >  arch/arm/mach-layerscape/soc.c       | 2 ++
> >  drivers/mci/imx-esdhc-pbl.c          | 3 ++-
> >  include/mach/layerscape/layerscape.h | 8 ++++++++
> >  3 files changed, 12 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/arm/mach-layerscape/soc.c b/arch/arm/mach-layerscape/soc.c
> > index 4d4ef05d4b..5f9d0d5171 100644
> > --- a/arch/arm/mach-layerscape/soc.c
> > +++ b/arch/arm/mach-layerscape/soc.c
> > @@ -91,6 +91,8 @@ static int ls1028a_init(void)
> >  
> >  	layerscape_register_pbl_image_handler();
> >  
> > +	reserve_sdram_region("tfa", LS1028A_TFA_RESERVED_START, LS1028A_TFA_RESERVED_SIZE);
> 
> Does this mean that the TF-A region is mapped executable (and therefore prefetchable)
> from early MMU setup time until this line has finished executing?

No, it doesn't. The TFA is placed at the end of lowmem and
barebox_arm_entry() is called with the real memory size
minus the space occupied by the TFA.

Nevertheless this patch needs a fixup. reserve_sdram_region() is called
before the full DDR is registered, so there's nothing to reserve from at
this point. I'll have to create a mmu_initcall() from it.

Sascha


> 
> > +
> >  	return 0;
> >  }
> >  
> > diff --git a/drivers/mci/imx-esdhc-pbl.c b/drivers/mci/imx-esdhc-pbl.c
> > index 2c74d101e4..2d071eaca8 100644
> > --- a/drivers/mci/imx-esdhc-pbl.c
> > +++ b/drivers/mci/imx-esdhc-pbl.c
> > @@ -21,6 +21,7 @@
> >  #endif
> >  #ifdef CONFIG_ARCH_LAYERSCAPE
> >  #include <mach/layerscape/xload.h>
> > +#include <mach/layerscape/layerscape.h>
> >  #endif
> >  #include "sdhci.h"
> >  #include "imx-esdhc.h"
> > @@ -387,7 +388,7 @@ static int ls1028a_esdhc_start_image(void __iomem *base, struct dram_regions_inf
> >  		.socdata = &data,
> >  	};
> >  	void *sdram = (void *)0x80000000;
> > -	void (*bl31)(void) = (void *)0xfbe00000;
> > +	void (*bl31)(void) = (void *)LS1028A_TFA_RESERVED_START;
> >  	size_t bl31_size;
> >  	void *bl31_image;
> >  	struct bl2_to_bl31_params_mem_v2 *params;
> > diff --git a/include/mach/layerscape/layerscape.h b/include/mach/layerscape/layerscape.h
> > index a048b7ef9e..6f420dd4f4 100644
> > --- a/include/mach/layerscape/layerscape.h
> > +++ b/include/mach/layerscape/layerscape.h
> > @@ -3,6 +3,8 @@
> >  #ifndef __MACH_LAYERSCAPE_H
> >  #define __MACH_LAYERSCAPE_H
> >  
> > +#include <linux/sizes.h>
> > +
> >  #define LS1046A_DDR_SDRAM_BASE		0x80000000
> >  #define LS1046A_DDR_FREQ		2100000000
> >  
> > @@ -16,6 +18,12 @@
> >  #define LS1028A_SP_SHARED_DRAM_SIZE	SZ_2M
> >  #define LS1028A_TZC400_BASE		0x01100000
> >  
> > +#define LS1028A_TFA_SIZE		SZ_64M
> > +#define LS1028A_TFA_SHRD		SZ_2M
> > +#define LS1028A_TFA_RESERVED_SIZE	(LS1028A_TFA_SIZE + LS1028A_TFA_SHRD)
> > +#define LS1028A_TFA_RESERVED_START	(0x100000000 - LS1028A_TFA_RESERVED_SIZE)
> > +#define LS1028A_TFA_START		(0x100000000 - LS1028A_TFA_SIZE)
> > +
> >  enum bootsource ls1046a_bootsource_get(void);
> >  enum bootsource ls1021a_bootsource_get(void);
> >  
> 
> -- 
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> 

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Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
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