On Mon, May 07, 2018 at 10:20:55AM +0800, Kever Yang wrote:
> Hi Marty,
>
>
> On 05/06/2018 10:25 PM, Marty E. Plummer wrote:
> > Taken from coreboot's src/soc/rockchip/rk3288/sdram.c
> >
> > Without this change, my u-boot build for the asus c201 chromebook (4GiB)
> > is incorrectly detected as 0 Bytes of ram.
>
> I know the root cause for this issue, and I have a local patch for it.
> The rk3288 is 32bit, and 4GB size is just out of range, so we need to before
> the max size before return with '<<20'. Sorry for forgot to send it out.
>
> >
> > Signed-off-by: Marty E. Plummer <hanetzer at startmail.com>
> > ---
> > arch/arm/mach-rockchip/sdram_common.c | 62 ++++++++++++++++-----------
> > 1 file changed, 37 insertions(+), 25 deletions(-)
> >
> > diff --git a/arch/arm/mach-rockchip/sdram_common.c b/arch/arm/mach-rockchip/sdram_common.c
> > index 76dbdc8715..a9c9f970a4 100644
> > --- a/arch/arm/mach-rockchip/sdram_common.c
> > +++ b/arch/arm/mach-rockchip/sdram_common.c
> > @@ -10,6 +10,8 @@
> > #include <asm/io.h>
> > #include <asm/arch/sdram_common.h>
> > #include <dm/uclass-internal.h>
> > +#include <linux/kernel.h>
> > +#include <linux/sizes.h>
> >
> > DECLARE_GLOBAL_DATA_PTR;
> > size_t rockchip_sdram_size(phys_addr_t reg)
> > @@ -19,34 +21,44 @@ size_t rockchip_sdram_size(phys_addr_t reg)
> > size_t size_mb = 0;
> > u32 ch;
> >
> > - u32 sys_reg = readl(reg);
> > - u32 ch_num = 1 + ((sys_reg >> SYS_REG_NUM_CH_SHIFT)
> > - & SYS_REG_NUM_CH_MASK);
> > + if (!size_mb) {
>
> I don't understand this and follow up changes, we don't really need it,
> isn't it?
> I think don't need the changes before here.
Yeah, that was just another level of indentation for the if (!size_mb)
guard, but I've reworked the patch to not do that as it was pointed out
that since size_mb is initialized to 0 prior.
> > + /*
> > + * we use the 0x00000000~0xfeffffff space
> > + * since 0xff000000~0xffffffff is soc register space
> > + * so we reserve it
> > + */
> > + size_mb = min(size_mb, 0xff000000/SZ_1M);
>
> This is what we really need, as Klaus point out, we need to use
> SDRAM_MAX_SIZE
> instead of hard code.
Yeah, I've got a rework on that which uses SDRAM_MAX_SIZE as instructed,
build and boot tested on my hardware.
>
> Thanks,
> - Kever
> > }
> >
> > return (size_t)size_mb << 20;
>
>
