Vaibhav Hiremath 7a867d149f greybus: arche-platform: Enable SVC clock during FW_FLASHING state ... The issue is, as part of kernel-only build we started seeing failures in SVC FW flashing. It was reproducible easily in kernel-only build, but never observed on Android build. During debugging, there were couple of observations, 1. If SVC clock enabled and disables (which is REFCLK_MAIN), then SVC FW flashing works. 2. If we do not switch SVC to HSE (external clock source) it works. Recently, SVC code has been updated to switch HSE clock, so removing it (remove/skip rcc_switch_ara_pll() fn) would use internal clock only. As per STM32 spec, for flashing through USART we do not need to enable HSE, but the above observation contradicts with it. There is still something missing in terms of understanding of how STM32 device functions as far as Flashing is concerned. There is something hidden in HW, which probably still need to identify. So as a interim solution we will enable clock for FW_FLASHING state, which seems to be fixing the issue here. Testing Done: Tested on EVT1.5 with arche6.0 and kernel-only build. Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org> Tested-by: Michael Scott <michael.scott@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>		2016-05-25 22:36:45 -07:00
drivers/staging/greybus	greybus: arche-platform: Enable SVC clock during FW_FLASHING state	2016-05-25 22:36:45 -07:00