[PATCH v6 15/16] OMAP2+: UART: Enable back uart clocks with runtime API for early console

Kevin Hilman khilman at ti.com
Tue Oct 11 17:06:16 EDT 2011


"Govindraj.R" <govindraj.raja at ti.com> writes:

> For the early console probing we had avoided hwmod reset and idling
> and uart was idled using hwmod API and enabled back using omap_device API
> after omap_device registration.
>
> Now since we are using runtime API's to enable back uart, move hwmod
> idling and use runtime API to enable back UART.
>
> Signed-off-by: Govindraj.R <govindraj.raja at ti.com>

Now that the driver is using runtime PM.  Why do we still need
HWMOD_INIT_NO_IDLE and HWMOD_INIT_NO_RESET?

The comment in the code says:

		/*
		 * During UART early init, device need to be probed
		 * to determine SoC specific init before omap_device
		 * is ready.  Therefore, don't allow idle here
		 */

This was true when using the 8250 driver because it was not using
runtime PM so could not know how to (re)enable the device.

However, since the driver is now runtime PM adapted, any device access
should be contained within a runtime PM get/put block, so there should
no longer be a reason not allow the IP blocks to be reset during boot.

Kevin




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