* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency @ 2013-11-22 14:07 ` ludovic.desroches at atmel.com 0 siblings, 0 replies; 16+ messages in thread From: ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w @ 2013-11-22 14:07 UTC (permalink / raw) To: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r Cc: nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w, plagnioj-sclMFOaUSTBWk0Htik3J/w, linux-i2c-u79uwXL29TY76Z2rM5mHXA, Ludovic Desroches From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> There are still I2C unexpected behaviors which are solved by reducing TWI internal frequency. Cc: <stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> #3.10+ Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> --- arch/arm/mach-at91/sama5d3.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c index 4012797..4ee0de5 100644 --- a/arch/arm/mach-at91/sama5d3.c +++ b/arch/arm/mach-at91/sama5d3.c @@ -95,19 +95,19 @@ static struct clk twi0_clk = { .name = "twi0_clk", .pid = SAMA5D3_ID_TWI0, .type = CLK_TYPE_PERIPHERAL, - .div = AT91_PMC_PCR_DIV2, + .div = AT91_PMC_PCR_DIV8, }; static struct clk twi1_clk = { .name = "twi1_clk", .pid = SAMA5D3_ID_TWI1, .type = CLK_TYPE_PERIPHERAL, - .div = AT91_PMC_PCR_DIV2, + .div = AT91_PMC_PCR_DIV8, }; static struct clk twi2_clk = { .name = "twi2_clk", .pid = SAMA5D3_ID_TWI2, .type = CLK_TYPE_PERIPHERAL, - .div = AT91_PMC_PCR_DIV2, + .div = AT91_PMC_PCR_DIV8, }; static struct clk mmc0_clk = { .name = "mci0_clk", -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency @ 2013-11-22 14:07 ` ludovic.desroches at atmel.com 0 siblings, 0 replies; 16+ messages in thread From: ludovic.desroches at atmel.com @ 2013-11-22 14:07 UTC (permalink / raw) To: linux-arm-kernel From: Ludovic Desroches <ludovic.desroches@atmel.com> There are still I2C unexpected behaviors which are solved by reducing TWI internal frequency. Cc: <stable@vger.kernel.org> #3.10+ Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> --- arch/arm/mach-at91/sama5d3.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c index 4012797..4ee0de5 100644 --- a/arch/arm/mach-at91/sama5d3.c +++ b/arch/arm/mach-at91/sama5d3.c @@ -95,19 +95,19 @@ static struct clk twi0_clk = { .name = "twi0_clk", .pid = SAMA5D3_ID_TWI0, .type = CLK_TYPE_PERIPHERAL, - .div = AT91_PMC_PCR_DIV2, + .div = AT91_PMC_PCR_DIV8, }; static struct clk twi1_clk = { .name = "twi1_clk", .pid = SAMA5D3_ID_TWI1, .type = CLK_TYPE_PERIPHERAL, - .div = AT91_PMC_PCR_DIV2, + .div = AT91_PMC_PCR_DIV8, }; static struct clk twi2_clk = { .name = "twi2_clk", .pid = SAMA5D3_ID_TWI2, .type = CLK_TYPE_PERIPHERAL, - .div = AT91_PMC_PCR_DIV2, + .div = AT91_PMC_PCR_DIV8, }; static struct clk mmc0_clk = { .name = "mci0_clk", -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 16+ messages in thread
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* Re: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 14:07 ` ludovic.desroches at atmel.com @ 2013-11-22 14:33 ` Wolfram Sang -1 siblings, 0 replies; 16+ messages in thread From: Wolfram Sang @ 2013-11-22 14:33 UTC (permalink / raw) To: ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w, plagnioj-sclMFOaUSTBWk0Htik3J/w, linux-i2c-u79uwXL29TY76Z2rM5mHXA [-- Attachment #1: Type: text/plain, Size: 1933 bytes --] On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org wrote: > From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> > > There are still I2C unexpected behaviors which are solved by reducing TWI > internal frequency. > > Cc: <stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> #3.10+ > Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> I think the commit message needs more details. Is this a true bugfix because the real bus frequency was too high because of the wrong divider? Is this a workaround which makes things work but will make the bus frequency slower than it should be? > --- > arch/arm/mach-at91/sama5d3.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c > index 4012797..4ee0de5 100644 > --- a/arch/arm/mach-at91/sama5d3.c > +++ b/arch/arm/mach-at91/sama5d3.c > @@ -95,19 +95,19 @@ static struct clk twi0_clk = { > .name = "twi0_clk", > .pid = SAMA5D3_ID_TWI0, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi1_clk = { > .name = "twi1_clk", > .pid = SAMA5D3_ID_TWI1, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi2_clk = { > .name = "twi2_clk", > .pid = SAMA5D3_ID_TWI2, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk mmc0_clk = { > .name = "mci0_clk", > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html [-- Attachment #2: Digital signature --] [-- Type: application/pgp-signature, Size: 836 bytes --] ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency @ 2013-11-22 14:33 ` Wolfram Sang 0 siblings, 0 replies; 16+ messages in thread From: Wolfram Sang @ 2013-11-22 14:33 UTC (permalink / raw) To: linux-arm-kernel On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches at atmel.com wrote: > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > There are still I2C unexpected behaviors which are solved by reducing TWI > internal frequency. > > Cc: <stable@vger.kernel.org> #3.10+ > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> I think the commit message needs more details. Is this a true bugfix because the real bus frequency was too high because of the wrong divider? Is this a workaround which makes things work but will make the bus frequency slower than it should be? > --- > arch/arm/mach-at91/sama5d3.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c > index 4012797..4ee0de5 100644 > --- a/arch/arm/mach-at91/sama5d3.c > +++ b/arch/arm/mach-at91/sama5d3.c > @@ -95,19 +95,19 @@ static struct clk twi0_clk = { > .name = "twi0_clk", > .pid = SAMA5D3_ID_TWI0, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi1_clk = { > .name = "twi1_clk", > .pid = SAMA5D3_ID_TWI1, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi2_clk = { > .name = "twi2_clk", > .pid = SAMA5D3_ID_TWI2, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk mmc0_clk = { > .name = "mci0_clk", > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in > the body of a message to majordomo at vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 836 bytes Desc: Digital signature URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20131122/6a9cebe4/attachment.sig> ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 14:33 ` Wolfram Sang (?) @ 2013-11-22 14:51 ` Ludovic Desroches [not found] ` <20131122145141.GB30749-tOglhBvtKaELqBSMlTbpHvU/3Eu2kcEP@public.gmane.org@atmel.com> -1 siblings, 1 reply; 16+ messages in thread From: Ludovic Desroches @ 2013-11-22 14:51 UTC (permalink / raw) To: linux-arm-kernel Hi Wolfram, On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: > On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches at atmel.com wrote: > > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > There are still I2C unexpected behaviors which are solved by reducing TWI > > internal frequency. > > > > Cc: <stable@vger.kernel.org> #3.10+ > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > I think the commit message needs more details. Is this a true bugfix > because the real bus frequency was too high because of the wrong > divider? Is this a workaround which makes things work but will make the > bus frequency slower than it should be? This fix doesn't concern the i2c bus frequency, only the internal IP frequency. TWI has been validated at 66MHz. With some devices, transfer hangs during i2c frame transmission. This issue disappears when reducing the internal frequency of the IP. Maybe there is some oversampling on i2c signals. Unfortunately, I have no clear status about the root cause that's why the commit message was imprecise. Regards Ludovic > > > --- > > arch/arm/mach-at91/sama5d3.c | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c > > index 4012797..4ee0de5 100644 > > --- a/arch/arm/mach-at91/sama5d3.c > > +++ b/arch/arm/mach-at91/sama5d3.c > > @@ -95,19 +95,19 @@ static struct clk twi0_clk = { > > .name = "twi0_clk", > > .pid = SAMA5D3_ID_TWI0, > > .type = CLK_TYPE_PERIPHERAL, > > - .div = AT91_PMC_PCR_DIV2, > > + .div = AT91_PMC_PCR_DIV8, > > }; > > static struct clk twi1_clk = { > > .name = "twi1_clk", > > .pid = SAMA5D3_ID_TWI1, > > .type = CLK_TYPE_PERIPHERAL, > > - .div = AT91_PMC_PCR_DIV2, > > + .div = AT91_PMC_PCR_DIV8, > > }; > > static struct clk twi2_clk = { > > .name = "twi2_clk", > > .pid = SAMA5D3_ID_TWI2, > > .type = CLK_TYPE_PERIPHERAL, > > - .div = AT91_PMC_PCR_DIV2, > > + .div = AT91_PMC_PCR_DIV8, > > }; > > static struct clk mmc0_clk = { > > .name = "mci0_clk", > > -- > > 1.7.9.5 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in > > the body of a message to majordomo at vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 16+ messages in thread
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* Re: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 14:51 ` Ludovic Desroches @ 2013-11-22 14:58 ` Wolfram Sang 0 siblings, 0 replies; 16+ messages in thread From: Wolfram Sang @ 2013-11-22 14:58 UTC (permalink / raw) To: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w, plagnioj-sclMFOaUSTBWk0Htik3J/w, linux-i2c-u79uwXL29TY76Z2rM5mHXA [-- Attachment #1: Type: text/plain, Size: 1403 bytes --] On Fri, Nov 22, 2013 at 03:51:41PM +0100, Ludovic Desroches wrote: > Hi Wolfram, > > On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: > > On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org wrote: > > > From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> > > > > > > There are still I2C unexpected behaviors which are solved by reducing TWI > > > internal frequency. > > > > > > Cc: <stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> #3.10+ > > > Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> > > > > I think the commit message needs more details. Is this a true bugfix > > because the real bus frequency was too high because of the wrong > > divider? Is this a workaround which makes things work but will make the > > bus frequency slower than it should be? > > This fix doesn't concern the i2c bus frequency, only the internal IP frequency. > > TWI has been validated at 66MHz. With some devices, transfer hangs during i2c > frame transmission. This issue disappears when reducing the internal frequency > of the IP. Maybe there is some oversampling on i2c signals. > Unfortunately, I have no clear status about the root cause that's why > the commit message was imprecise. This paragraph is a way better commit message IMO :) [-- Attachment #2: Digital signature --] [-- Type: application/pgp-signature, Size: 836 bytes --] ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency @ 2013-11-22 14:58 ` Wolfram Sang 0 siblings, 0 replies; 16+ messages in thread From: Wolfram Sang @ 2013-11-22 14:58 UTC (permalink / raw) To: linux-arm-kernel On Fri, Nov 22, 2013 at 03:51:41PM +0100, Ludovic Desroches wrote: > Hi Wolfram, > > On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: > > On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches at atmel.com wrote: > > > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > > > There are still I2C unexpected behaviors which are solved by reducing TWI > > > internal frequency. > > > > > > Cc: <stable@vger.kernel.org> #3.10+ > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > I think the commit message needs more details. Is this a true bugfix > > because the real bus frequency was too high because of the wrong > > divider? Is this a workaround which makes things work but will make the > > bus frequency slower than it should be? > > This fix doesn't concern the i2c bus frequency, only the internal IP frequency. > > TWI has been validated at 66MHz. With some devices, transfer hangs during i2c > frame transmission. This issue disappears when reducing the internal frequency > of the IP. Maybe there is some oversampling on i2c signals. > Unfortunately, I have no clear status about the root cause that's why > the commit message was imprecise. This paragraph is a way better commit message IMO :) -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 836 bytes Desc: Digital signature URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20131122/7a20bd79/attachment.sig> ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 14:58 ` Wolfram Sang (?) @ 2013-11-22 15:07 ` Ludovic Desroches -1 siblings, 0 replies; 16+ messages in thread From: Ludovic Desroches @ 2013-11-22 15:07 UTC (permalink / raw) To: Wolfram Sang Cc: plagnioj, Ludovic Desroches, nicolas.ferre, linux-i2c, linux-arm-kernel On Fri, Nov 22, 2013 at 03:58:35PM +0100, Wolfram Sang wrote: > On Fri, Nov 22, 2013 at 03:51:41PM +0100, Ludovic Desroches wrote: > > Hi Wolfram, > > > > On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: > > > On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches@atmel.com wrote: > > > > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > > > > > There are still I2C unexpected behaviors which are solved by reducing TWI > > > > internal frequency. > > > > > > > > Cc: <stable@vger.kernel.org> #3.10+ > > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > > > I think the commit message needs more details. Is this a true bugfix > > > because the real bus frequency was too high because of the wrong > > > divider? Is this a workaround which makes things work but will make the > > > bus frequency slower than it should be? > > > > This fix doesn't concern the i2c bus frequency, only the internal IP frequency. > > > > TWI has been validated at 66MHz. With some devices, transfer hangs during i2c > > frame transmission. This issue disappears when reducing the internal frequency > > of the IP. Maybe there is some oversampling on i2c signals. > > Unfortunately, I have no clear status about the root cause that's why > > the commit message was imprecise. > > This paragraph is a way better commit message IMO :) > Ok I'll update it. Thanks for the review Wolfram. Regards Ludovic ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 14:58 ` Wolfram Sang (?) (?) @ 2013-11-22 15:07 ` Ludovic Desroches [not found] ` <20131122150734.GC30749-tOglhBvtKaELqBSMlTbpHvU/3Eu2kcEP@public.gmane.org@atmel.com> -1 siblings, 1 reply; 16+ messages in thread From: Ludovic Desroches @ 2013-11-22 15:07 UTC (permalink / raw) To: linux-arm-kernel On Fri, Nov 22, 2013 at 03:58:35PM +0100, Wolfram Sang wrote: > On Fri, Nov 22, 2013 at 03:51:41PM +0100, Ludovic Desroches wrote: > > Hi Wolfram, > > > > On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: > > > On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches at atmel.com wrote: > > > > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > > > > > There are still I2C unexpected behaviors which are solved by reducing TWI > > > > internal frequency. > > > > > > > > Cc: <stable@vger.kernel.org> #3.10+ > > > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > > > I think the commit message needs more details. Is this a true bugfix > > > because the real bus frequency was too high because of the wrong > > > divider? Is this a workaround which makes things work but will make the > > > bus frequency slower than it should be? > > > > This fix doesn't concern the i2c bus frequency, only the internal IP frequency. > > > > TWI has been validated at 66MHz. With some devices, transfer hangs during i2c > > frame transmission. This issue disappears when reducing the internal frequency > > of the IP. Maybe there is some oversampling on i2c signals. > > Unfortunately, I have no clear status about the root cause that's why > > the commit message was imprecise. > > This paragraph is a way better commit message IMO :) > Ok I'll update it. Thanks for the review Wolfram. Regards Ludovic ^ permalink raw reply [flat|nested] 16+ messages in thread
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* Re: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 15:07 ` Ludovic Desroches @ 2013-11-22 15:09 ` Nicolas Ferre 0 siblings, 0 replies; 16+ messages in thread From: Nicolas Ferre @ 2013-11-22 15:09 UTC (permalink / raw) To: Wolfram Sang, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, plagnioj-sclMFOaUSTBWk0Htik3J/w, linux-i2c-u79uwXL29TY76Z2rM5mHXA, Ludovic Desroches On 22/11/2013 16:07, Ludovic Desroches : > On Fri, Nov 22, 2013 at 03:58:35PM +0100, Wolfram Sang wrote: >> On Fri, Nov 22, 2013 at 03:51:41PM +0100, Ludovic Desroches wrote: >>> Hi Wolfram, >>> >>> On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: >>>> On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org wrote: >>>>> From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> >>>>> >>>>> There are still I2C unexpected behaviors which are solved by reducing TWI >>>>> internal frequency. >>>>> >>>>> Cc: <stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> #3.10+ >>>>> Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> >>>> >>>> I think the commit message needs more details. Is this a true bugfix >>>> because the real bus frequency was too high because of the wrong >>>> divider? Is this a workaround which makes things work but will make the >>>> bus frequency slower than it should be? >>> >>> This fix doesn't concern the i2c bus frequency, only the internal IP frequency. >>> >>> TWI has been validated at 66MHz. With some devices, transfer hangs during i2c >>> frame transmission. This issue disappears when reducing the internal frequency >>> of the IP. Maybe there is some oversampling on i2c signals. >>> Unfortunately, I have no clear status about the root cause that's why >>> the commit message was imprecise. >> >> This paragraph is a way better commit message IMO :) >> > > Ok I'll update it. Ludo, you can also add my: Acked-by: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> Bye, > Thanks for the review Wolfram. > > Regards > > Ludovic > > -- Nicolas Ferre ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency @ 2013-11-22 15:09 ` Nicolas Ferre 0 siblings, 0 replies; 16+ messages in thread From: Nicolas Ferre @ 2013-11-22 15:09 UTC (permalink / raw) To: linux-arm-kernel On 22/11/2013 16:07, Ludovic Desroches : > On Fri, Nov 22, 2013 at 03:58:35PM +0100, Wolfram Sang wrote: >> On Fri, Nov 22, 2013 at 03:51:41PM +0100, Ludovic Desroches wrote: >>> Hi Wolfram, >>> >>> On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: >>>> On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches at atmel.com wrote: >>>>> From: Ludovic Desroches <ludovic.desroches@atmel.com> >>>>> >>>>> There are still I2C unexpected behaviors which are solved by reducing TWI >>>>> internal frequency. >>>>> >>>>> Cc: <stable@vger.kernel.org> #3.10+ >>>>> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> >>>> >>>> I think the commit message needs more details. Is this a true bugfix >>>> because the real bus frequency was too high because of the wrong >>>> divider? Is this a workaround which makes things work but will make the >>>> bus frequency slower than it should be? >>> >>> This fix doesn't concern the i2c bus frequency, only the internal IP frequency. >>> >>> TWI has been validated at 66MHz. With some devices, transfer hangs during i2c >>> frame transmission. This issue disappears when reducing the internal frequency >>> of the IP. Maybe there is some oversampling on i2c signals. >>> Unfortunately, I have no clear status about the root cause that's why >>> the commit message was imprecise. >> >> This paragraph is a way better commit message IMO :) >> > > Ok I'll update it. Ludo, you can also add my: Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Bye, > Thanks for the review Wolfram. > > Regards > > Ludovic > > -- Nicolas Ferre ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 14:33 ` Wolfram Sang (?) (?) @ 2013-11-22 14:51 ` Ludovic Desroches -1 siblings, 0 replies; 16+ messages in thread From: Ludovic Desroches @ 2013-11-22 14:51 UTC (permalink / raw) To: Wolfram Sang Cc: plagnioj, Ludovic Desroches, nicolas.ferre, linux-i2c, linux-arm-kernel Hi Wolfram, On Fri, Nov 22, 2013 at 03:33:51PM +0100, Wolfram Sang wrote: > On Fri, Nov 22, 2013 at 03:07:08PM +0100, ludovic.desroches@atmel.com wrote: > > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > > > There are still I2C unexpected behaviors which are solved by reducing TWI > > internal frequency. > > > > Cc: <stable@vger.kernel.org> #3.10+ > > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > > I think the commit message needs more details. Is this a true bugfix > because the real bus frequency was too high because of the wrong > divider? Is this a workaround which makes things work but will make the > bus frequency slower than it should be? This fix doesn't concern the i2c bus frequency, only the internal IP frequency. TWI has been validated at 66MHz. With some devices, transfer hangs during i2c frame transmission. This issue disappears when reducing the internal frequency of the IP. Maybe there is some oversampling on i2c signals. Unfortunately, I have no clear status about the root cause that's why the commit message was imprecise. Regards Ludovic > > > --- > > arch/arm/mach-at91/sama5d3.c | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c > > index 4012797..4ee0de5 100644 > > --- a/arch/arm/mach-at91/sama5d3.c > > +++ b/arch/arm/mach-at91/sama5d3.c > > @@ -95,19 +95,19 @@ static struct clk twi0_clk = { > > .name = "twi0_clk", > > .pid = SAMA5D3_ID_TWI0, > > .type = CLK_TYPE_PERIPHERAL, > > - .div = AT91_PMC_PCR_DIV2, > > + .div = AT91_PMC_PCR_DIV8, > > }; > > static struct clk twi1_clk = { > > .name = "twi1_clk", > > .pid = SAMA5D3_ID_TWI1, > > .type = CLK_TYPE_PERIPHERAL, > > - .div = AT91_PMC_PCR_DIV2, > > + .div = AT91_PMC_PCR_DIV8, > > }; > > static struct clk twi2_clk = { > > .name = "twi2_clk", > > .pid = SAMA5D3_ID_TWI2, > > .type = CLK_TYPE_PERIPHERAL, > > - .div = AT91_PMC_PCR_DIV2, > > + .div = AT91_PMC_PCR_DIV8, > > }; > > static struct clk mmc0_clk = { > > .name = "mci0_clk", > > -- > > 1.7.9.5 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 14:07 ` ludovic.desroches at atmel.com @ 2013-11-22 15:01 ` boris brezillon -1 siblings, 0 replies; 16+ messages in thread From: boris brezillon @ 2013-11-22 15:01 UTC (permalink / raw) To: ludovic.desroches, linux-arm-kernel; +Cc: nicolas.ferre, plagnioj, linux-i2c Hi Ludovic, On 22/11/2013 15:07, ludovic.desroches@atmel.com wrote: > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > There are still I2C unexpected behaviors which are solved by reducing TWI > internal frequency. I guess I should do the same for the dt version of sama5 clks. Nicolas, what do you think ? Best Regards, Boris > > Cc: <stable@vger.kernel.org> #3.10+ > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > --- > arch/arm/mach-at91/sama5d3.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c > index 4012797..4ee0de5 100644 > --- a/arch/arm/mach-at91/sama5d3.c > +++ b/arch/arm/mach-at91/sama5d3.c > @@ -95,19 +95,19 @@ static struct clk twi0_clk = { > .name = "twi0_clk", > .pid = SAMA5D3_ID_TWI0, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi1_clk = { > .name = "twi1_clk", > .pid = SAMA5D3_ID_TWI1, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi2_clk = { > .name = "twi2_clk", > .pid = SAMA5D3_ID_TWI2, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk mmc0_clk = { > .name = "mci0_clk", > ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency @ 2013-11-22 15:01 ` boris brezillon 0 siblings, 0 replies; 16+ messages in thread From: boris brezillon @ 2013-11-22 15:01 UTC (permalink / raw) To: linux-arm-kernel Hi Ludovic, On 22/11/2013 15:07, ludovic.desroches at atmel.com wrote: > From: Ludovic Desroches <ludovic.desroches@atmel.com> > > There are still I2C unexpected behaviors which are solved by reducing TWI > internal frequency. I guess I should do the same for the dt version of sama5 clks. Nicolas, what do you think ? Best Regards, Boris > > Cc: <stable@vger.kernel.org> #3.10+ > Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> > --- > arch/arm/mach-at91/sama5d3.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c > index 4012797..4ee0de5 100644 > --- a/arch/arm/mach-at91/sama5d3.c > +++ b/arch/arm/mach-at91/sama5d3.c > @@ -95,19 +95,19 @@ static struct clk twi0_clk = { > .name = "twi0_clk", > .pid = SAMA5D3_ID_TWI0, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi1_clk = { > .name = "twi1_clk", > .pid = SAMA5D3_ID_TWI1, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk twi2_clk = { > .name = "twi2_clk", > .pid = SAMA5D3_ID_TWI2, > .type = CLK_TYPE_PERIPHERAL, > - .div = AT91_PMC_PCR_DIV2, > + .div = AT91_PMC_PCR_DIV8, > }; > static struct clk mmc0_clk = { > .name = "mci0_clk", > ^ permalink raw reply [flat|nested] 16+ messages in thread
[parent not found: <528F71BD.2080407-ZNYIgs0QAGpBDgjK7y7TUQ@public.gmane.org>]
* Re: [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency 2013-11-22 15:01 ` boris brezillon @ 2013-11-22 15:11 ` Nicolas Ferre -1 siblings, 0 replies; 16+ messages in thread From: Nicolas Ferre @ 2013-11-22 15:11 UTC (permalink / raw) To: boris brezillon, ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r Cc: plagnioj-sclMFOaUSTBWk0Htik3J/w, linux-i2c-u79uwXL29TY76Z2rM5mHXA On 22/11/2013 16:01, boris brezillon : > Hi Ludovic, > > On 22/11/2013 15:07, ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org wrote: >> From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> >> >> There are still I2C unexpected behaviors which are solved by reducing TWI >> internal frequency. > > I guess I should do the same for the dt version of sama5 clks. > Nicolas, what do you think ? Yes, you can queue these modification on top of your "CCF related fixes" branch. Bye, >> Cc: <stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> #3.10+ >> Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> >> --- >> arch/arm/mach-at91/sama5d3.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c >> index 4012797..4ee0de5 100644 >> --- a/arch/arm/mach-at91/sama5d3.c >> +++ b/arch/arm/mach-at91/sama5d3.c >> @@ -95,19 +95,19 @@ static struct clk twi0_clk = { >> .name = "twi0_clk", >> .pid = SAMA5D3_ID_TWI0, >> .type = CLK_TYPE_PERIPHERAL, >> - .div = AT91_PMC_PCR_DIV2, >> + .div = AT91_PMC_PCR_DIV8, >> }; >> static struct clk twi1_clk = { >> .name = "twi1_clk", >> .pid = SAMA5D3_ID_TWI1, >> .type = CLK_TYPE_PERIPHERAL, >> - .div = AT91_PMC_PCR_DIV2, >> + .div = AT91_PMC_PCR_DIV8, >> }; >> static struct clk twi2_clk = { >> .name = "twi2_clk", >> .pid = SAMA5D3_ID_TWI2, >> .type = CLK_TYPE_PERIPHERAL, >> - .div = AT91_PMC_PCR_DIV2, >> + .div = AT91_PMC_PCR_DIV8, >> }; >> static struct clk mmc0_clk = { >> .name = "mci0_clk", >> > > > -- Nicolas Ferre ^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency @ 2013-11-22 15:11 ` Nicolas Ferre 0 siblings, 0 replies; 16+ messages in thread From: Nicolas Ferre @ 2013-11-22 15:11 UTC (permalink / raw) To: linux-arm-kernel On 22/11/2013 16:01, boris brezillon : > Hi Ludovic, > > On 22/11/2013 15:07, ludovic.desroches at atmel.com wrote: >> From: Ludovic Desroches <ludovic.desroches@atmel.com> >> >> There are still I2C unexpected behaviors which are solved by reducing TWI >> internal frequency. > > I guess I should do the same for the dt version of sama5 clks. > Nicolas, what do you think ? Yes, you can queue these modification on top of your "CCF related fixes" branch. Bye, >> Cc: <stable@vger.kernel.org> #3.10+ >> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> >> --- >> arch/arm/mach-at91/sama5d3.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/arch/arm/mach-at91/sama5d3.c b/arch/arm/mach-at91/sama5d3.c >> index 4012797..4ee0de5 100644 >> --- a/arch/arm/mach-at91/sama5d3.c >> +++ b/arch/arm/mach-at91/sama5d3.c >> @@ -95,19 +95,19 @@ static struct clk twi0_clk = { >> .name = "twi0_clk", >> .pid = SAMA5D3_ID_TWI0, >> .type = CLK_TYPE_PERIPHERAL, >> - .div = AT91_PMC_PCR_DIV2, >> + .div = AT91_PMC_PCR_DIV8, >> }; >> static struct clk twi1_clk = { >> .name = "twi1_clk", >> .pid = SAMA5D3_ID_TWI1, >> .type = CLK_TYPE_PERIPHERAL, >> - .div = AT91_PMC_PCR_DIV2, >> + .div = AT91_PMC_PCR_DIV8, >> }; >> static struct clk twi2_clk = { >> .name = "twi2_clk", >> .pid = SAMA5D3_ID_TWI2, >> .type = CLK_TYPE_PERIPHERAL, >> - .div = AT91_PMC_PCR_DIV2, >> + .div = AT91_PMC_PCR_DIV8, >> }; >> static struct clk mmc0_clk = { >> .name = "mci0_clk", >> > > > -- Nicolas Ferre ^ permalink raw reply [flat|nested] 16+ messages in thread
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2013-11-22 14:07 [PATCH] ARM: at91: sama5d3: reduce TWI internal clock frequency ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w
2013-11-22 14:07 ` ludovic.desroches at atmel.com
[not found] ` <1385129228-11225-1-git-send-email-ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
2013-11-22 14:33 ` Wolfram Sang
2013-11-22 14:33 ` Wolfram Sang
2013-11-22 14:51 ` Ludovic Desroches
[not found] ` <20131122145141.GB30749-tOglhBvtKaELqBSMlTbpHvU/3Eu2kcEP@public.gmane.org@atmel.com>
2013-11-22 14:58 ` Wolfram Sang
2013-11-22 14:58 ` Wolfram Sang
2013-11-22 15:07 ` Ludovic Desroches
2013-11-22 15:07 ` Ludovic Desroches
[not found] ` <20131122150734.GC30749-tOglhBvtKaELqBSMlTbpHvU/3Eu2kcEP@public.gmane.org@atmel.com>
2013-11-22 15:09 ` Nicolas Ferre
2013-11-22 15:09 ` Nicolas Ferre
2013-11-22 14:51 ` Ludovic Desroches
2013-11-22 15:01 ` boris brezillon
2013-11-22 15:01 ` boris brezillon
[not found] ` <528F71BD.2080407-ZNYIgs0QAGpBDgjK7y7TUQ@public.gmane.org>
2013-11-22 15:11 ` Nicolas Ferre
2013-11-22 15:11 ` Nicolas Ferre
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