sh: lockless gpio_set_value()
This patch optimizes the gpio data register handling for gpio_set_value(). Instead of using the good old spinlock-plus-read-modify-write strategy we now use a shadow register and atomic operations. This improves the bitbanging mmc performance on Migo-R from 26 Kbytes/s to 40 Kbytes/s. Signed-off-by: NMagnus Damm <damm@igel.co.jp> Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Showing
想要评论请 注册 或 登录