For the lcdif clock get_rate looks as follows:
read div from HW_CLKCTRL_DIS_LCDIF.DIV
return clk_get_rate(clk->parent) / div
with clk->parent being ref_pix_clk on my system.
ref_pix_clk's rate depends on HW_CLKCTRL_FRAC1.PIXFRAC.
The set_rate function for lcdif does:
parent_rate = clk_get_rate(clk->parent);
based on that calculate frac and div such that
parent_rate * 18 / frac / div is near the requested rate.
HW_CLKCTRL_FRAC1.PIXFRAC is updated with frac
HW_CLKCTRL_DIS_LCDIF.DIV is updated with div
For this calculation to be correct parent_rate needs to be
initialized not with the clock rate of lcdif's parent (i.e. ref_pix) but
that of its grandparent (i.e. ref_pix' parent == pll0_clk).
The obvious downside of this patch is that now set_rate(lcdif) changes
its parent's rate, too. Still this is better than a wrong rate.
Acked-by: Shawn Guo <shawn.guo@freescale.com>
LAKML-Reference: 20110225084950.GA13684@S2101-09.ap.freescale.net
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Most likely, the LCD panel on mx28 platform will require a pixel
clock higher than ref_xtal_clk (24 MHz), so the patch initializes
the parent of lcdif clock as ref_pix_clk.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Commit b2878fa (ARM: mx28: update clock and device name for dual fec
support) added only the new lookups without removing the old one.
Cc: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
_CLK_SET_RATE does not only handle the cpu clock but also other
clocks, so do not hardcode the HW_CLKCTRL_CPU register.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
reg | (1 << clk->enable_shift) always evaluates to true. Switch it
to & which makes much more sense
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
Since commit
6d803ba (ARM: 6483/1: arm & sh: factorised duplicated clkdev.c)
platforms need to select CLKDEV_LOOKUP instead of COMMON_CLKDEV and need
to include <linux/clkdev.h>.
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
The mxs duart is actually an amba-pl011 device. This commit changes
the duart device code to dynamically allocate amba-pl011 device,
so that drivers/serial/amba-pl011.c can be used on mxs.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Change device name from "fec" to "imx28-fec", so that fec driver
can distinguish mx28.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>