On Fri, Jan 24, 2020 at 09:16:58AM -0500, Sasha Levin wrote:
From: Lubomir Rintel lkundrak@v3.sk
[ Upstream commit 8bea5ac0fbc5b2103f8779ddff216122e3c2e1ad ]
Determined empirically, no documentation is available.
The OLPC XO-1.75 laptop used parent 1, that one being VCTCXO/4 (65MHz), but thought it's a VCTCXO/2 (130MHz). The mmp2 timer driver, not knowing what is going on, ended up just dividing the rate as of commit f36797ee4380 ("ARM: mmp/mmp2: dt: enable the clock")'
Hi,
this has to go together with this one (in other stable trees too):
commit 0bd0f30bbf060891f58866a46083a9931f71787c Author: Lubomir Rintel lkundrak@v3.sk Date: Wed Dec 18 20:04:53 2019 +0100
ARM: mmp: do not divide the clock rate
This was done because the clock driver returned the wrong rate, which is fixed in "clk: mmp2: Fix the order of timer mux parents" patch.
It removes a workaround for the same issue from before it was understood what is going on. If it stays, the clock will run twice as fast.
Thanks Lubo
Link: https://lore.kernel.org/r/20191218190454.420358-3-lkundrak@v3.sk Signed-off-by: Lubomir Rintel lkundrak@v3.sk Acked-by: Stephen Boyd sboyd@kernel.org Signed-off-by: Olof Johansson olof@lixom.net Signed-off-by: Sasha Levin sashal@kernel.org
drivers/clk/mmp/clk-of-mmp2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/clk/mmp/clk-of-mmp2.c b/drivers/clk/mmp/clk-of-mmp2.c index a60a1be937ad6..b4a95cbbda989 100644 --- a/drivers/clk/mmp/clk-of-mmp2.c +++ b/drivers/clk/mmp/clk-of-mmp2.c @@ -134,7 +134,7 @@ static DEFINE_SPINLOCK(ssp3_lock); static const char *ssp_parent_names[] = {"vctcxo_4", "vctcxo_2", "vctcxo", "pll1_16"}; static DEFINE_SPINLOCK(timer_lock); -static const char *timer_parent_names[] = {"clk32", "vctcxo_2", "vctcxo_4", "vctcxo"}; +static const char *timer_parent_names[] = {"clk32", "vctcxo_4", "vctcxo_2", "vctcxo"}; static DEFINE_SPINLOCK(reset_lock); -- 2.20.1