* [PATCH] ARM: imx35: don't disable the uart clock when DEBUG_LL is in use @ 2012-07-31 13:44 Uwe Kleine-König 2012-07-31 17:43 ` Sascha Hauer 0 siblings, 1 reply; 5+ messages in thread From: Uwe Kleine-König @ 2012-07-31 13:44 UTC (permalink / raw) To: linux-arm-kernel Otherwise printch et al. and printk with earlyprintk and keep_bootcon becomes unfunctional when the clk framework disables all unused clocks. Signed-off-by: Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de> --- arch/arm/mach-imx/clk-imx35.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm/mach-imx/clk-imx35.c b/arch/arm/mach-imx/clk-imx35.c index c6422fb..83d614c 100644 --- a/arch/arm/mach-imx/clk-imx35.c +++ b/arch/arm/mach-imx/clk-imx35.c @@ -271,6 +271,10 @@ int __init mx35_clocks_init() */ clk_prepare_enable(clk[scc_gate]); + /* Assert that the UART clock keeps running if DEBUG_LL is in use */ + if (IS_ENABLED(CONFIG_DEBUG_IMX31_IMX35_UART)) + clk_prepare_enable(clk[uart1_gate]); + imx_print_silicon_rev("i.MX35", mx35_revision()); #ifdef CONFIG_MXC_USE_EPIT -- 1.7.10.4 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH] ARM: imx35: don't disable the uart clock when DEBUG_LL is in use 2012-07-31 13:44 [PATCH] ARM: imx35: don't disable the uart clock when DEBUG_LL is in use Uwe Kleine-König @ 2012-07-31 17:43 ` Sascha Hauer 2012-07-31 18:32 ` Uwe Kleine-König 0 siblings, 1 reply; 5+ messages in thread From: Sascha Hauer @ 2012-07-31 17:43 UTC (permalink / raw) To: linux-arm-kernel On Tue, Jul 31, 2012 at 03:44:39PM +0200, Uwe Kleine-K?nig wrote: > Otherwise printch et al. and printk with earlyprintk and keep_bootcon > becomes unfunctional when the clk framework disables all unused clocks. Why don't you use the regular console? Letting the clock framework disable the clocks was pretty much intentional. Sascha > > Signed-off-by: Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de> > --- > arch/arm/mach-imx/clk-imx35.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/arm/mach-imx/clk-imx35.c b/arch/arm/mach-imx/clk-imx35.c > index c6422fb..83d614c 100644 > --- a/arch/arm/mach-imx/clk-imx35.c > +++ b/arch/arm/mach-imx/clk-imx35.c > @@ -271,6 +271,10 @@ int __init mx35_clocks_init() > */ > clk_prepare_enable(clk[scc_gate]); > > + /* Assert that the UART clock keeps running if DEBUG_LL is in use */ > + if (IS_ENABLED(CONFIG_DEBUG_IMX31_IMX35_UART)) > + clk_prepare_enable(clk[uart1_gate]); > + > imx_print_silicon_rev("i.MX35", mx35_revision()); > > #ifdef CONFIG_MXC_USE_EPIT > -- > 1.7.10.4 > > -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] ARM: imx35: don't disable the uart clock when DEBUG_LL is in use 2012-07-31 17:43 ` Sascha Hauer @ 2012-07-31 18:32 ` Uwe Kleine-König 2012-08-06 14:24 ` Uwe Kleine-König 0 siblings, 1 reply; 5+ messages in thread From: Uwe Kleine-König @ 2012-07-31 18:32 UTC (permalink / raw) To: linux-arm-kernel Hello Sascha, On Tue, Jul 31, 2012 at 07:43:58PM +0200, Sascha Hauer wrote: > On Tue, Jul 31, 2012 at 03:44:39PM +0200, Uwe Kleine-K?nig wrote: > > Otherwise printch et al. and printk with earlyprintk and keep_bootcon > > becomes unfunctional when the clk framework disables all unused clocks. > > Why don't you use the regular console? Letting the clock framework > disable the clocks was pretty much intentional. I don't question that disabling unused clocks is sensible. But usually if you enable DEBUG_LL you want to use it even after the clock framework disabled all (apparently) unused clocks. And in my case the regular console didn't work yet and so I relied on earlyprintk. Even if the problem proved to be the result of my stupidity this patch asserts that earlyprintk just works as it should be for debug aids. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-K?nig | Industrial Linux Solutions | http://www.pengutronix.de/ | ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] ARM: imx35: don't disable the uart clock when DEBUG_LL is in use 2012-07-31 18:32 ` Uwe Kleine-König @ 2012-08-06 14:24 ` Uwe Kleine-König 2012-08-06 14:35 ` Sascha Hauer 0 siblings, 1 reply; 5+ messages in thread From: Uwe Kleine-König @ 2012-08-06 14:24 UTC (permalink / raw) To: linux-arm-kernel On Tue, Jul 31, 2012 at 08:32:06PM +0200, Uwe Kleine-K?nig wrote: > Hello Sascha, > > On Tue, Jul 31, 2012 at 07:43:58PM +0200, Sascha Hauer wrote: > > On Tue, Jul 31, 2012 at 03:44:39PM +0200, Uwe Kleine-K?nig wrote: > > > Otherwise printch et al. and printk with earlyprintk and keep_bootcon > > > becomes unfunctional when the clk framework disables all unused clocks. > > > > Why don't you use the regular console? Letting the clock framework > > disable the clocks was pretty much intentional. > I don't question that disabling unused clocks is sensible. But usually > if you enable DEBUG_LL you want to use it even after the clock framework > disabled all (apparently) unused clocks. And in my case the regular > console didn't work yet and so I relied on earlyprintk. > Even if the problem proved to be the result of my stupidity this patch > asserts that earlyprintk just works as it should be for debug aids. ping -- Pengutronix e.K. | Uwe Kleine-K?nig | Industrial Linux Solutions | http://www.pengutronix.de/ | ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] ARM: imx35: don't disable the uart clock when DEBUG_LL is in use 2012-08-06 14:24 ` Uwe Kleine-König @ 2012-08-06 14:35 ` Sascha Hauer 0 siblings, 0 replies; 5+ messages in thread From: Sascha Hauer @ 2012-08-06 14:35 UTC (permalink / raw) To: linux-arm-kernel On Mon, Aug 06, 2012 at 04:24:06PM +0200, Uwe Kleine-K?nig wrote: > On Tue, Jul 31, 2012 at 08:32:06PM +0200, Uwe Kleine-K?nig wrote: > > Hello Sascha, > > > > On Tue, Jul 31, 2012 at 07:43:58PM +0200, Sascha Hauer wrote: > > > On Tue, Jul 31, 2012 at 03:44:39PM +0200, Uwe Kleine-K?nig wrote: > > > > Otherwise printch et al. and printk with earlyprintk and keep_bootcon > > > > becomes unfunctional when the clk framework disables all unused clocks. > > > > > > Why don't you use the regular console? Letting the clock framework > > > disable the clocks was pretty much intentional. > > I don't question that disabling unused clocks is sensible. But usually > > if you enable DEBUG_LL you want to use it even after the clock framework > > disabled all (apparently) unused clocks. And in my case the regular > > console didn't work yet and so I relied on earlyprintk. > > Even if the problem proved to be the result of my stupidity this patch > > asserts that earlyprintk just works as it should be for debug aids. > ping Honestly, I don't think this is a good idea. You fixed one UART on one SoC, so ARRAY_SIZE(i.MX1, i.MX21, i.MX25, i.MX27, i.MX31, i.MX35, i.MX51, i.MX53, i.MX6) * NUM_UARTS remain broken for this usecase. IMO DEBUG_LL is to get some stuff out of an otherwise silent board, nothing more. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2012-08-06 14:35 UTC | newest] Thread overview: 5+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2012-07-31 13:44 [PATCH] ARM: imx35: don't disable the uart clock when DEBUG_LL is in use Uwe Kleine-König 2012-07-31 17:43 ` Sascha Hauer 2012-07-31 18:32 ` Uwe Kleine-König 2012-08-06 14:24 ` Uwe Kleine-König 2012-08-06 14:35 ` Sascha Hauer
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