[PATCH] riscv: spacemit: k1: probe dram size during boot phase.

[Huan Zhou]

On Wed, Jan 08, 2025 at 07:11:05PM +0800, Yixun Lan wrote:
> Hi Huan:
> 
> On 16:49 Wed 08 Jan     , Huan Zhou wrote:
> > 
> > 
> ..
> > ---
> remove above "---"? otherwise following commit message will be
> dropped during patch application..
> 
> > This patch introduce improvement for get dram size on bananapi BPI-F3,
> > retrieving the dram size dynamically.
> > Have tested on bananapi BPIF3 4G and jupiter 8G.
> > 
> > Signed-off-by: Huan Zhou <me at per1cycle.org>
> > ---
> >  arch/riscv/cpu/k1/dram.c | 40 ++++++++++++++++++++++++++++++++++++++--
> >  1 file changed, 38 insertions(+), 2 deletions(-)
> > 
> > diff --git a/arch/riscv/cpu/k1/dram.c b/arch/riscv/cpu/k1/dram.c
> > index c477c15cbfb19f0e3a0ee72985b602f5bda352d7..095217f2a4c053f7477d62c0776bcb51e623db47 100644
> > --- a/arch/riscv/cpu/k1/dram.c
> > +++ b/arch/riscv/cpu/k1/dram.c
> > @@ -4,17 +4,53 @@
> >   */
> >  
> >  #include <asm/global_data.h>
> > +#include <asm/io.h>
> >  #include <config.h>
> > +#include <bitfield.h>
> >  #include <fdt_support.h>
> >  #include <linux/sizes.h>
> >  
> > +#define DDR_BASE 0xC0000000
> >  DECLARE_GLOBAL_DATA_PTR;
> >  
> > +static inline u32 map_format_size(u32 val)
> > +{
> > +	u32 tmp;
> > +
> > +	if (val & 0x1 == 0)
> please add brackets explicitly, something like
> 	if ((val & 0x1) == 0)
ok, mb, will correct and test in next version.
> 
> > +		return 0;
> > +
> > +	tmp = bitfield_extract(val, 16, 5);
> > +	switch (tmp) {
> > +	case 0xd:
> > +		return 512;
> > +	case 0xe:
> > +		return 1024;
> > +	case 0xf:
> > +		return 2048;
> > +	case 0x10:
> > +		return 4096;
> > +	case 0x11:
> > +		return 8192;
> > +	default:
> > +		pr_info("Invalid DRAM density %x\n", val);
> > +		return 0;
> > +	}
> > +}
> > +
> > +u32 ddr_get_density(void)
> > +{
> > +	u32 cs0_size = map_format_size(readl((void *)DDR_BASE + 0x200));
> > +	u32 cs1_size = map_format_size(readl((void *)DDR_BASE + 0x208));
> > +	u32 ddr_size = cs0_size + cs1_size;
> > +
> > +	return ddr_size;
> > +}
> > +
> >  int dram_init(void)
> >  {
> >  	gd->ram_base = CFG_SYS_SDRAM_BASE;
> > -	/* TODO get ram size from ddr controller */
> > -	gd->ram_size = SZ_4G;
> > +	gd->ram_size = (u64)ddr_get_density() * SZ_1M;
> while using cast, why not define ddr_get_density() return as same type?
> also it's more reasonable to use phys_size_t as I checked gd_t
ok, got it.
> 
> >  	return 0;
> >  }
> >  
> > 
> > ---
> > base-commit: 19fc0b7f7d907119a13e9c207991899f0817f8fc
> > change-id: 20250108-get-dram-size-65cf59a15201
> > 
> > Best regards,
> > -- 
> > Huan Zhou <me at per1cycle.org>
> > 
> 
> -- 
> Yixun Lan (dlan)
> Gentoo Linux Developer
> GPG Key ID AABEFD55