Kevin,
On Wed, Oct 29, 2014 at 12:01 PM, Kevin Hilman <khilman at kernel.org> wrote:
>> + /* set bit 8 so that system will resume to FAST_BOOT_ADDR */
>> + regmap_write(sgrf_regmap, RK3288_SGRF_SOC_CON0,
>> + BIT(SGRF_FAST_BOOT_EN) | BIT(SGRF_FAST_BOOT_EN + 16));
>
> Comment says "bit 8", but code says bit 8 and bit 24, and if bit 24 is
> needed, it should probably get its own #define in the header.
This is Rockchip's "write enable" feature hitting us again. The upper
16-bits are "write enables" for the lower 16-bits. So to set bit 8
you set bit 8 to whatever value you want and then 'write enable' by
setting (1 << 8 << 16). It allows you to avoid read-modify-write.
See this in Rockchip's clk.h:
#define HIWORD_UPDATE(val, mask, shift) \
((val) << (shift) | (mask) << ((shift) + 16))
