On 7 May 2018, at 04:34, Marty E. Plummer hanetzer@startmail.com wrote:
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@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.
In that case you just masked the problem but didn’t solve it: assuming size_mb is size_t (I’ll assume this is 64bit, but did not check), then your 4GB is 0x1_0000_0000 ) which overflows to 0x0 when converted to a u32.
In other words: we need to figure out where the truncation occurs (image what happens if a new 32bit processor with LPAE comes out…).
Thanks,
- Kever
}
return (size_t)size_mb << 20;
U-Boot mailing list U-Boot@lists.denx.de mailto:U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot https://lists.denx.de/listinfo/u-boot