Re: [PATCH v1] platform/x86: pmc_atom: Fix parent clocks

From: Pierre-Louis Bossart
Date: Mon Nov 06 2017 - 11:59:48 EST




On 11/06/2017 08:17 AM, Andy Shevchenko wrote:
PLL or XTAL is a choice of parents. They are not dependent to
each other (direct citation):

On Baytrail the PLL takes the 25MHz xtal input and generates a 19.2 MHZ Mclk. they are related and completely dependent.

On Cherrytrail, the xtal is 19.2 MHz so there is no need for a PLL mode.

Not sure what you are trying to fix...


The source of the frequencies can be XTAL or PLL, depending on
the configuration. Any of the two available frequencies can be
selected for each of the platform clocks.

According to datasheet on hand CherryTrail has them, though they both
provide 19.2MHz frequency.

Fixes: 282a4e4ce5f9 ("platform/x86: Enable Atom PMC platform clocks")
Cc: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/platform/x86/pmc_atom.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/pmc_atom.c b/drivers/platform/x86/pmc_atom.c
index 77bac859342d..56734112e5fe 100644
--- a/drivers/platform/x86/pmc_atom.c
+++ b/drivers/platform/x86/pmc_atom.c
@@ -65,7 +65,7 @@ static const struct pmc_clk byt_clks[] = {
{
.name = "pll",
.freq = 19200000,
- .parent_name = "xtal",
+ .parent_name = NULL,
},
{},
};
@@ -76,6 +76,11 @@ static const struct pmc_clk cht_clks[] = {
.freq = 19200000,
.parent_name = NULL,
},
+ {
+ .name = "pll",
+ .freq = 19200000,
+ .parent_name = NULL,
+ },
{},
};