[PATCH 09/15] clk: sunxi-ng: r40: Force LOSC parent to RTC LOSC output
From: Maxime Ripard <hidden>
Date: 2018-11-28 10:26:14
Also in:
linux-clk, linux-devicetree, linux-rtc, lkml
On Wed, Nov 28, 2018 at 05:30:07PM +0800, Chen-Yu Tsai wrote:
On the R40, in addition to a mux between the RTC's own RC oscillator and an external 32768 Hz crystal, which are muxed inside the RTC module, the CCU also has its own RC oscillator, which runs at around 2 MHz, and can be muxed with the LOSC output from the RTC. This muxed output is called "SYS 32K" in the module clock diagram, but otherwise referred to as the LOSC throughout the CCU documentation. The RC oscillator is not very accurate, even though it has an undocumented calibration function. We really want a precise clock at 32768 Hz, instead of something at around 32 KHz. This patch forces the SYS 32K clock to use the RTC output as its parent, and doesn't bother registering the internal oscillator nor a clock mux. Signed-off-by: Chen-Yu Tsai <redacted>
Acked-by: Maxime Ripard <redacted> Maxime -- Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 228 bytes Desc: not available URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20181128/931ba379/attachment.sig>