| Message ID | 1397621648-15691-1-git-send-email-lokeshvutla@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/16/2014 07:14 AM, Lokesh Vutla wrote: > WDT1 module can take one of the below clocks as input functional > clock - > - On-Chip 32K RC Osc [default/reset] > - 32K from PRCM > > The On-Chip 32K RC Osc clock is not an accurate clock-source as per > the design/spec, so as a result, for example, timer which supposed > to get expired @60Sec, but will expire somewhere ~@40Sec, which is > not expected by any use-case. > > The solution here is to switch the input clock-source to PRCM > generated 32K clock-source during boot-time itself. > This is derived from AM33xx clock file. I guess this patch should wait until we have a proper solution upstream for selecting parents based on DT data, unless you have pressing need to merge this as a temporary hack. -Tero > > Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com> > --- > drivers/clk/ti/clk-43xx.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/clk/ti/clk-43xx.c b/drivers/clk/ti/clk-43xx.c > index 67c8de5..ae2524e 100644 > --- a/drivers/clk/ti/clk-43xx.c > +++ b/drivers/clk/ti/clk-43xx.c > @@ -110,9 +110,22 @@ static struct ti_dt_clk am43xx_clks[] = { > > int __init am43xx_dt_clk_init(void) > { > + struct clk *clk1, *clk2; > + > ti_dt_clocks_register(am43xx_clks); > > omap2_clk_disable_autoidle_all(); > > + /* > + * The On-Chip 32K RC Osc clock is not an accurate clock-source as per > + * the design/spec, so as a result, for example, timer which supposed > + * to get expired @60Sec, but will expire somewhere ~@40Sec, which is > + * not expected by any use-case, so change WDT1 clock source to PRCM > + * 32KHz clock. > + */ > + clk1 = clk_get_sys(NULL, "wdt1_fck"); > + clk2 = clk_get_sys(NULL, "clkdiv32k_ick"); > + clk_set_parent(clk1, clk2); > + > return 0; > } > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/22/2014 01:06 PM, Tero Kristo wrote: > On 04/16/2014 07:14 AM, Lokesh Vutla wrote: >> WDT1 module can take one of the below clocks as input functional >> clock - >> - On-Chip 32K RC Osc [default/reset] >> - 32K from PRCM >> >> The On-Chip 32K RC Osc clock is not an accurate clock-source as per >> the design/spec, so as a result, for example, timer which supposed >> to get expired @60Sec, but will expire somewhere ~@40Sec, which is >> not expected by any use-case. >> >> The solution here is to switch the input clock-source to PRCM >> generated 32K clock-source during boot-time itself. >> This is derived from AM33xx clock file. > > I guess this patch should wait until we have a proper solution upstream > for selecting parents based on DT data, unless you have pressing need to > merge this as a temporary hack. I've decided to take this patch in its current form as the DT parenting is still WIP. Queued for 3.16/ti-clk-drv. -Tero > >> >> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com> >> --- >> drivers/clk/ti/clk-43xx.c | 13 +++++++++++++ >> 1 file changed, 13 insertions(+) >> >> diff --git a/drivers/clk/ti/clk-43xx.c b/drivers/clk/ti/clk-43xx.c >> index 67c8de5..ae2524e 100644 >> --- a/drivers/clk/ti/clk-43xx.c >> +++ b/drivers/clk/ti/clk-43xx.c >> @@ -110,9 +110,22 @@ static struct ti_dt_clk am43xx_clks[] = { >> >> int __init am43xx_dt_clk_init(void) >> { >> + struct clk *clk1, *clk2; >> + >> ti_dt_clocks_register(am43xx_clks); >> >> omap2_clk_disable_autoidle_all(); >> >> + /* >> + * The On-Chip 32K RC Osc clock is not an accurate clock-source >> as per >> + * the design/spec, so as a result, for example, timer which >> supposed >> + * to get expired @60Sec, but will expire somewhere ~@40Sec, >> which is >> + * not expected by any use-case, so change WDT1 clock source to PRCM >> + * 32KHz clock. >> + */ >> + clk1 = clk_get_sys(NULL, "wdt1_fck"); >> + clk2 = clk_get_sys(NULL, "clkdiv32k_ick"); >> + clk_set_parent(clk1, clk2); >> + >> return 0; >> } >> > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/clk/ti/clk-43xx.c b/drivers/clk/ti/clk-43xx.c index 67c8de5..ae2524e 100644 --- a/drivers/clk/ti/clk-43xx.c +++ b/drivers/clk/ti/clk-43xx.c @@ -110,9 +110,22 @@ static struct ti_dt_clk am43xx_clks[] = { int __init am43xx_dt_clk_init(void) { + struct clk *clk1, *clk2; + ti_dt_clocks_register(am43xx_clks); omap2_clk_disable_autoidle_all(); + /* + * The On-Chip 32K RC Osc clock is not an accurate clock-source as per + * the design/spec, so as a result, for example, timer which supposed + * to get expired @60Sec, but will expire somewhere ~@40Sec, which is + * not expected by any use-case, so change WDT1 clock source to PRCM + * 32KHz clock. + */ + clk1 = clk_get_sys(NULL, "wdt1_fck"); + clk2 = clk_get_sys(NULL, "clkdiv32k_ick"); + clk_set_parent(clk1, clk2); + return 0; }
WDT1 module can take one of the below clocks as input functional clock - - On-Chip 32K RC Osc [default/reset] - 32K from PRCM The On-Chip 32K RC Osc clock is not an accurate clock-source as per the design/spec, so as a result, for example, timer which supposed to get expired @60Sec, but will expire somewhere ~@40Sec, which is not expected by any use-case. The solution here is to switch the input clock-source to PRCM generated 32K clock-source during boot-time itself. This is derived from AM33xx clock file. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com> --- drivers/clk/ti/clk-43xx.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)