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20bde64343
I found that the probe function of dwc2 driver takes much time when kernel boot up. There are many long delays in the probe function these take almost 1 second. This patch trying to reduce unnecessary delay time. In dwc2_core_reset() I see it use two at least 20ms delays to wait AHB idle and core soft reset, but dwc2 data book said that dwc2 core soft reset and AHB idle just need a few clocks (I think it refers to AHB clock, and AHB clock run at 150MHz in my RK3288 board), so 20ms is too long, delay 1us for wait AHB idle and soft reset is enough. And in dwc2_get_hwparams() it takes 150ms to wait ForceHostMode and ForceDeviceMode valid but in data book it said software must wait at least 25ms before the change to take effect, so I reduce this time to 25ms~50ms. By the way, is there any state bit show that the force mode take effect ? Could we poll curmod bit for figuring out if the change take effect ? It seems that usleep_range() at boot time will pick the longest value in the range. In dwc2_core_reset() there is a very long delay takes 200ms, and this function run twice when probe, could any one tell me is this delay time resonable ? I have tried this patch in my RK3288-evb board. It works well. Signed-off-by: Yunzhi Li <lyz@rock-chips.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Felipe Balbi <balbi@ti.com> |
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| .. | ||
| core_intr.c | ||
| core.c | ||
| core.h | ||
| debug.h | ||
| debugfs.c | ||
| gadget.c | ||
| hcd_ddma.c | ||
| hcd_intr.c | ||
| hcd_queue.c | ||
| hcd.c | ||
| hcd.h | ||
| hw.h | ||
| Kconfig | ||
| Makefile | ||
| pci.c | ||
| platform.c | ||