[PATCH 1/8] CLK: ti: dra7: Initialize USB_DPLL

Tony Lindgren tony at atomide.com
Fri Mar 7 11:55:14 EST 2014


* Tero Kristo <t-kristo at ti.com> [140307 05:46]:
> On 03/07/2014 03:09 PM, Roger Quadros wrote:
> >USB_DPLL must be initialized and locked at boot so that
> >USB modules can work.
> >
> >Also program USB_DLL_M2 output to half rate.
> >
> >CC: Mike Turquette <mturquette at linaro.org>
> >CC: Tero Kristo <t-kristo at ti.com>
> >Signed-off-by: Roger Quadros <rogerq at ti.com>
> >---
> >  drivers/clk/ti/clk-7xx.c | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> >
> >diff --git a/drivers/clk/ti/clk-7xx.c b/drivers/clk/ti/clk-7xx.c
> >index 9977653..f89f3c2 100644
> >--- a/drivers/clk/ti/clk-7xx.c
> >+++ b/drivers/clk/ti/clk-7xx.c
> >@@ -18,6 +18,7 @@
> >
> >  #define DRA7_DPLL_ABE_DEFFREQ				361267200
> >  #define DRA7_DPLL_GMAC_DEFFREQ				1000000000
> >+#define DRA7_DPLL_USB_DEFFREQ				960000000
> >
> >
> >  static struct ti_dt_clk dra7xx_clks[] = {
> >@@ -328,5 +329,15 @@ int __init dra7xx_dt_clk_init(void)
> >  	if (rc)
> >  		pr_err("%s: failed to configure GMAC DPLL!\n", __func__);
> >
> >+	dpll_ck = clk_get_sys(NULL, "dpll_usb_ck");
> >+	rc = clk_set_rate(dpll_ck, DRA7_DPLL_USB_DEFFREQ);
> >+	if (rc)
> >+		pr_err("%s: failed to configure USB DPLL!\n", __func__);
> >+
> >+	dpll_ck = clk_get_sys(NULL, "dpll_usb_m2_ck");
> >+	rc = clk_set_rate(dpll_ck, DRA7_DPLL_USB_DEFFREQ/2);
> >+	if (rc)
> >+		pr_err("%s: failed to set USB_DPLL M2 OUT\n", __func__);
> >+
> 
> I would rather see this done using the default-rate mechanism provided here:
> 
> https://www.mail-archive.com/linux-omap@vger.kernel.org/msg101300.html
> 
> However, this remains to be commented by Mike whether the patch is
> okay or not.

Yes let's wait for that and not add hacks for new features.

Regards,

Tony



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