[U-Boot] [PATCH] ARMV7: OMAP4: Calculate SDRAM size

Steve Sakoman steve at sakoman.com
Sun Sep 26 04:37:34 CEST 2010


On Sat, 2010-09-25 at 10:00 -0500, Nishanth Menon wrote:
> On 09/23/2010 04:12 PM, Steve Sakoman wrote:
> > From: Aneesh V<aneesh at ti.com>
> >
> > Calculate the SDRAM size from DMM configuration registers instead of using
> > hard-coded values. This gives correct values for all different boards.
> >
> > It's assumed that DMM sections do not overlap memory areas.
> 
> How do we handle NOR boot? is it assumed that the configuration will be 
> done way befor the sdram_init?

None of the OMAP4 board configs currently supported in u-boot utilize
NOR boot.

I would expect that NOR boot patches would be submitted when a
board/config that requires it is added.  We shouldn't add code for NOR
until there is a need.

Steve





> > Signed-off-by: Aneesh V<aneesh at ti.com>
> > Tested-by: Steve Sakoman<steve at sakoman.com>
> > ---
> >   arch/arm/cpu/armv7/omap4/board.c        |   30 +++++++++++++++++++++++++++++-
> >   arch/arm/include/asm/arch-omap4/omap4.h |   10 ++++++++++
> >   2 files changed, 39 insertions(+), 1 deletions(-)
> >
> > diff --git a/arch/arm/cpu/armv7/omap4/board.c b/arch/arm/cpu/armv7/omap4/board.c
> > index 195be6e..8c1f395 100644
> > --- a/arch/arm/cpu/armv7/omap4/board.c
> > +++ b/arch/arm/cpu/armv7/omap4/board.c
> > @@ -30,6 +30,7 @@
> >   #include<common.h>
> >   #include<asm/arch/cpu.h>
> >   #include<asm/arch/sys_proto.h>
> > +#include<asm/sizes.h>
> >
> >   /*
> >    * Routine: s_init
> > @@ -66,6 +67,33 @@ void watchdog_init(void)
> >   	writel(WD_UNLOCK2,&wd2_base->wspr);
> >   }
> >
> > +
> > +/*
> > + * This function finds the SDRAM size available in the system
> > + * based on DMM section configurations
> > + * This is needed because the size of memory installed may be
> > + * different on different versions of the board
> > + */
> > +u32 sdram_size(void)
> > +{
> > +	u32 section, i, total_size = 0, size, addr;
> > +	for (i = 0; i<  4; i++) {
> > +		section	= __raw_readl(DMM_LISA_MAP_BASE + i*4);
> > +		addr = section&  DMM_LISA_MAP_SYS_ADDR_MASK;
> > +		/* See if the address is valid */
> > +		if ((addr>= OMAP44XX_DRAM_ADDR_SPACE_START)&&
> > +		    (addr<  OMAP44XX_DRAM_ADDR_SPACE_END)) {
> > +			size	= ((section&  DMM_LISA_MAP_SYS_SIZE_MASK)>>
> > +				    DMM_LISA_MAP_SYS_SIZE_SHIFT);
> > +			size	= 1<<  size;
> > +			size	*= SZ_16M;
> > +			total_size += size;
> > +		}
> > +	}
> > +	return total_size;
> > +}
> > +
> > +
> >   /*
> >    * Routine: dram_init
> >    * Description: sets uboots idea of sdram size
> > @@ -75,7 +103,7 @@ int dram_init(void)
> >   	DECLARE_GLOBAL_DATA_PTR;
> >
> >   	gd->bd->bi_dram[0].start = 0x80000000;
> > -	gd->bd->bi_dram[0].size = 512<<  20;
> > +	gd->bd->bi_dram[0].size = sdram_size();
> >   	return 0;
> >   }
> >
> > diff --git a/arch/arm/include/asm/arch-omap4/omap4.h b/arch/arm/include/asm/arch-omap4/omap4.h
> > index d0c808d..a30bb33 100644
> > --- a/arch/arm/include/asm/arch-omap4/omap4.h
> > +++ b/arch/arm/include/asm/arch-omap4/omap4.h
> > @@ -42,6 +42,10 @@
> >   #define OMAP44XX_L4_WKUP_BASE	0x4A300000
> >   #define OMAP44XX_L4_PER_BASE	0x48000000
> >
> > +#define OMAP44XX_DRAM_ADDR_SPACE_START	0x80000000
> > +#define OMAP44XX_DRAM_ADDR_SPACE_END	0xD0000000
> > +
> > +
> >   /* CONTROL */
> >   #define CTRL_BASE		(OMAP44XX_L4_CORE_BASE + 0x2000)
> >   #define CONTROL_PADCONF_CORE	(OMAP44XX_L4_CORE_BASE + 0x100000)
> > @@ -66,6 +70,12 @@
> >   /* GPMC */
> >   #define OMAP44XX_GPMC_BASE	0x50000000
> >
> > +/* DMM */
> > +#define OMAP44XX_DMM_BASE		0x4E000000
> > +#define DMM_LISA_MAP_BASE		(OMAP44XX_DMM_BASE + 0x40)
> > +#define DMM_LISA_MAP_SYS_SIZE_MASK	(7<<  20)
> > +#define DMM_LISA_MAP_SYS_SIZE_SHIFT	20
> > +#define DMM_LISA_MAP_SYS_ADDR_MASK	(0xFF<<  24)
> >   /*
> >    * Hardware Register Details
> >    */
> 




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