| Message ID | 20170512182251.23948-1-alexandre.belloni@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, May 12, 2017 at 08:22:51PM +0200, Alexandre Belloni wrote: > On sama5d2, power to the core may be cut while entering suspend mode. It is > necessary to save and restore the TCB registers. > > Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> > --- > Changes in v2: > - use writel instead of __raw_writel > - Document sequence > - use ARRAY_SIZE(tcb_cache) instead of 3 > > drivers/clocksource/tcb_clksrc.c | 51 ++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 51 insertions(+) > > diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c Hi, what should I do with this patch as the patched file is supposed to be removed [1]. -- Daniel [1] https://www.spinics.net/lists/kernel/msg2520390.html
On 06/06/2017 at 18:48:17 +0200, Daniel Lezcano wrote: > On Fri, May 12, 2017 at 08:22:51PM +0200, Alexandre Belloni wrote: > > On sama5d2, power to the core may be cut while entering suspend mode. It is > > necessary to save and restore the TCB registers. > > > > Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> > > --- > > Changes in v2: > > - use writel instead of __raw_writel > > - Document sequence > > - use ARRAY_SIZE(tcb_cache) instead of 3 > > > > drivers/clocksource/tcb_clksrc.c | 51 ++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 51 insertions(+) > > > > diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c > > Hi, > > what should I do with this patch as the patched file is supposed to be removed > [1]. > I feel like we are far from reaching an agreement on the other series so it is still worth applying.
On 06/06/2017 20:09, Alexandre Belloni wrote: > On 06/06/2017 at 18:48:17 +0200, Daniel Lezcano wrote: >> On Fri, May 12, 2017 at 08:22:51PM +0200, Alexandre Belloni wrote: >>> On sama5d2, power to the core may be cut while entering suspend mode. It is >>> necessary to save and restore the TCB registers. >>> >>> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> >>> --- >>> Changes in v2: >>> - use writel instead of __raw_writel >>> - Document sequence >>> - use ARRAY_SIZE(tcb_cache) instead of 3 >>> >>> drivers/clocksource/tcb_clksrc.c | 51 ++++++++++++++++++++++++++++++++++++++++ >>> 1 file changed, 51 insertions(+) >>> >>> diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c >> >> Hi, >> >> what should I do with this patch as the patched file is supposed to be removed >> [1]. >> > > I feel like we are far from reaching an agreement on the other series so > it is still worth applying. Ok.
On 12/05/2017 20:22, Alexandre Belloni wrote: > On sama5d2, power to the core may be cut while entering suspend mode. It is > necessary to save and restore the TCB registers. > > Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> The context will be saved/restored on all the platforms (other than sama5d2) using this timer even if the clock is not powered down. Is that ok? Should it be tagged for stable@? Side note: the config option is in drivers/misc, any particular reason to have it there and not in the clocksource's Kconfig?
On 13/06/2017 at 14:21:10 +0200, Daniel Lezcano wrote: > On 12/05/2017 20:22, Alexandre Belloni wrote: > > On sama5d2, power to the core may be cut while entering suspend mode. It is > > necessary to save and restore the TCB registers. > > > > Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> > > The context will be saved/restored on all the platforms (other than > sama5d2) using this timer even if the clock is not powered down. Is that ok? > Yes, that is fine. There is not much we can do here until we can determine what is the target suspend state from the drivers. > Should it be tagged for stable@? > No because support for this suspend mode is not yet upstream. > Side note: the config option is in drivers/misc, any particular reason > to have it there and not in the clocksource's Kconfig? > Mostly historical, this is changed in the other series.
On 13/06/2017 14:28, Alexandre Belloni wrote: > On 13/06/2017 at 14:21:10 +0200, Daniel Lezcano wrote: >> On 12/05/2017 20:22, Alexandre Belloni wrote: >>> On sama5d2, power to the core may be cut while entering suspend mode. It is >>> necessary to save and restore the TCB registers. >>> >>> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> >> >> The context will be saved/restored on all the platforms (other than >> sama5d2) using this timer even if the clock is not powered down. Is that ok? >> > > Yes, that is fine. There is not much we can do here until we can > determine what is the target suspend state from the drivers. > >> Should it be tagged for stable@? >> > > No because support for this suspend mode is not yet upstream. > >> Side note: the config option is in drivers/misc, any particular reason >> to have it there and not in the clocksource's Kconfig? >> > > Mostly historical, this is changed in the other series. Ok, thanks. I've applied this patch for 4.13. -- Daniel
diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c index d4ca9962a759..828729c70a0c 100644 --- a/drivers/clocksource/tcb_clksrc.c +++ b/drivers/clocksource/tcb_clksrc.c @@ -9,6 +9,7 @@ #include <linux/ioport.h> #include <linux/io.h> #include <linux/platform_device.h> +#include <linux/syscore_ops.h> #include <linux/atmel_tc.h> @@ -40,6 +41,14 @@ */ static void __iomem *tcaddr; +static struct +{ + u32 cmr; + u32 imr; + u32 rc; + bool clken; +} tcb_cache[3]; +static u32 bmr_cache; static u64 tc_get_cycles(struct clocksource *cs) { @@ -61,12 +70,54 @@ static u64 tc_get_cycles32(struct clocksource *cs) return __raw_readl(tcaddr + ATMEL_TC_REG(0, CV)); } +void tc_clksrc_suspend(struct clocksource *cs) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(tcb_cache); i++) { + tcb_cache[i].cmr = readl(tcaddr + ATMEL_TC_REG(i, CMR)); + tcb_cache[i].imr = readl(tcaddr + ATMEL_TC_REG(i, IMR)); + tcb_cache[i].rc = readl(tcaddr + ATMEL_TC_REG(i, RC)); + tcb_cache[i].clken = !!(readl(tcaddr + ATMEL_TC_REG(i, SR)) & + ATMEL_TC_CLKSTA); + } + + bmr_cache = readl(tcaddr + ATMEL_TC_BMR); +} + +void tc_clksrc_resume(struct clocksource *cs) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(tcb_cache); i++) { + /* Restore registers for the channel, RA and RB are not used */ + writel(tcb_cache[i].cmr, tcaddr + ATMEL_TC_REG(i, CMR)); + writel(tcb_cache[i].rc, tcaddr + ATMEL_TC_REG(i, RC)); + writel(0, tcaddr + ATMEL_TC_REG(i, RA)); + writel(0, tcaddr + ATMEL_TC_REG(i, RB)); + /* Disable all the interrupts */ + writel(0xff, tcaddr + ATMEL_TC_REG(i, IDR)); + /* Reenable interrupts that were enabled before suspending */ + writel(tcb_cache[i].imr, tcaddr + ATMEL_TC_REG(i, IER)); + /* Start the clock if it was used */ + if (tcb_cache[i].clken) + writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(i, CCR)); + } + + /* Dual channel, chain channels */ + writel(bmr_cache, tcaddr + ATMEL_TC_BMR); + /* Finally, trigger all the channels*/ + writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR); +} + static struct clocksource clksrc = { .name = "tcb_clksrc", .rating = 200, .read = tc_get_cycles, .mask = CLOCKSOURCE_MASK(32), .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .suspend = tc_clksrc_suspend, + .resume = tc_clksrc_resume, }; #ifdef CONFIG_GENERIC_CLOCKEVENTS
On sama5d2, power to the core may be cut while entering suspend mode. It is necessary to save and restore the TCB registers. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> --- Changes in v2: - use writel instead of __raw_writel - Document sequence - use ARRAY_SIZE(tcb_cache) instead of 3 drivers/clocksource/tcb_clksrc.c | 51 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+)