[U-Boot] [PATCHv2 1/2] ARMv8/fsl-layerscape: Correct the OCRAM size

[Z.Q. Hou]

Hi York,

Thanks a lot for your comments!

> -----Original Message-----
> From: york sun
> Sent: 2016年12月17日 0:39
> To: Z.Q. Hou <zhiqiang.hou at nxp.com>; u-boot at lists.denx.de; Prabhakar
> Kushwaha <prabhakar.kushwaha at nxp.com>; Ruchika Gupta
> <ruchika.gupta at nxp.com>; Mingkai Hu <mingkai.hu at nxp.com>; Pratiyush
> Srivastava <pratiyush.srivastava at nxp.com>
> Subject: Re: [PATCHv2 1/2] ARMv8/fsl-layerscape: Correct the OCRAM size
> 
> On 12/16/2016 01:29 AM, Zhiqiang Hou wrote:
> > From: Hou Zhiqiang <Zhiqiang.Hou at nxp.com>
> >
> > The real size of OCRAM is 128KiB, so correct the size of OCRAM.
> > And OCRAM reserved 2MiB space, then add a new macro to describe it,
> > which is used for MMU setup.
> >
> > Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou at nxp.com>
> > ---
> > V2:
> >  - New patch
> >
> >  arch/arm/include/asm/arch-fsl-layerscape/config.h | 8 +++++---
> >  arch/arm/include/asm/arch-fsl-layerscape/cpu.h    | 8 ++++----
> >  2 files changed, 9 insertions(+), 7 deletions(-)
> >
> > diff --git a/arch/arm/include/asm/arch-fsl-layerscape/config.h
> > b/arch/arm/include/asm/arch-fsl-layerscape/config.h
> > index c50894a..8e2eea3 100644
> > --- a/arch/arm/include/asm/arch-fsl-layerscape/config.h
> > +++ b/arch/arm/include/asm/arch-fsl-layerscape/config.h
> > @@ -28,8 +28,9 @@
> >  #define CONFIG_FSL_TZASC_400
> >  #endif
> >
> > -#define CONFIG_SYS_FSL_OCRAM_BASE	0x18000000	/* initial RAM */
> > -#define CONFIG_SYS_FSL_OCRAM_SIZE	0x00200000	/* 2M */
> > +#define CONFIG_SYS_FSL_OCRAM_BASE	0x18000000 /* initial RAM */
> > +#define SYS_FSL_OCRAM_SPACE_SIZE	0x00200000 /* 2M space */
> > +#define CONFIG_SYS_FSL_OCRAM_SIZE	0x00020000 /* Real size 128K */
> 
> 
> 
> >
> >  /* DDR */
> >  #define CONFIG_SYS_LS2_DDR_BLOCK1_SIZE	((phys_size_t)2 << 30)
> > @@ -137,7 +138,8 @@
> >  #elif defined(CONFIG_FSL_LSCH2)
> >  #define CONFIG_SYS_FSL_SEC_COMPAT		5
> >  #define CONFIG_SYS_FSL_OCRAM_BASE		0x10000000 /* initial
> RAM */
> > -#define CONFIG_SYS_FSL_OCRAM_SIZE		0x00200000 /* 2M */
> > +#define SYS_FSL_OCRAM_SPACE_SIZE		0x00200000 /* 2M space */
> 
> 
> Zhiqiang,
> 
> The history behind the OCRAM size is page table size. We started from fixed
> table. 2MB was the page granule size to avoid too many tables.
> With now MMU code, we can use 4KB page granule to get rid of this macro,
> but I'd rather not to create a new table just for this purpose.
> 
> I see you want to use the real OCRAM size to initialize it. Why don't you use a
> new macro like SYS_FSL_OCRAM_REAL_SIZE so you don't have to change
> other code. Or better use Kconfig option for the new macro.
> 

The OCRAM_SIZE and OCRAM_REAL_SIZE, I afraid it is confusing.
I think the OCRAM size and OCRAM base are hardware attributes and it's better to stay them in the config.h.

Thanks,
Zhiqiang