From mboxrd@z Thu Jan 1 00:00:00 1970 From: j-keerthy@ti.com (J, KEERTHY) Date: Wed, 22 Aug 2018 16:37:47 +0530 Subject: [PATCH] soc: ti: pm33xx: Enable DS0 for the platforms on which it is functional In-Reply-To: <20180822084318.GN14967@localhost> References: <1534915951-8783-1-git-send-email-j-keerthy@ti.com> <20180822073409.GK14967@localhost> <20180822073719.GL14967@localhost> <20180822084318.GN14967@localhost> Message-ID: <335b4efe-ab18-df83-35f2-ee232c09f2e3@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 8/22/2018 2:13 PM, Johan Hovold wrote: > On Wed, Aug 22, 2018 at 01:50:29PM +0530, J, KEERTHY wrote: >> >> >> On 8/22/2018 1:07 PM, Johan Hovold wrote: >>> On Wed, Aug 22, 2018 at 09:34:09AM +0200, Johan Hovold wrote: >>>> On Wed, Aug 22, 2018 at 11:02:31AM +0530, Keerthy wrote: >>>>> Enable DS0 for only those platforms on which it is functional >>>>> >>>>> Signed-off-by: Keerthy >>>>> --- >>>>> arch/arm/mach-omap2/pm33xx-core.c | 5 +++++ >>>>> drivers/soc/ti/pm33xx.c | 9 +++++++++ >>>>> include/linux/platform_data/pm33xx.h | 2 ++ >>>>> 3 files changed, 16 insertions(+) >>>>> >>>>> diff --git a/arch/arm/mach-omap2/pm33xx-core.c b/arch/arm/mach-omap2/pm33xx-core.c >>>>> index f4971e4..f0f6e8e 100644 >>>>> --- a/arch/arm/mach-omap2/pm33xx-core.c >>>>> +++ b/arch/arm/mach-omap2/pm33xx-core.c >>>>> @@ -135,6 +135,11 @@ static int am43xx_suspend(unsigned int state, int (*fn)(unsigned long), >>>>> { >>>>> int ret = 0; >>>>> >>>>> + if (!(args & WFI_FLAG_DEEP_SLEEP0)) { >>>>> + pr_err("DS0 mode not supported\n"); >>>>> + return -ENOTSUPP; >>>>> + } >>>>> + >>>>> amx3_pre_suspend_common(); >>>>> scu_power_mode(scu_base, SCU_PM_POWEROFF); >>>>> ret = cpu_suspend(args, fn); >>>>> diff --git a/drivers/soc/ti/pm33xx.c b/drivers/soc/ti/pm33xx.c >>>>> index d0dab32..53238d7 100644 >>>>> --- a/drivers/soc/ti/pm33xx.c >>>>> +++ b/drivers/soc/ti/pm33xx.c >>>>> @@ -324,6 +324,15 @@ static int am33xx_pm_probe(struct platform_device *pdev) >>>>> suspend_wfi_flags |= WFI_FLAG_SAVE_EMIF; >>>>> suspend_wfi_flags |= WFI_FLAG_WAKE_M3; >>>>> >>>>> + /* >>>>> + * Deep Sleep0 mode is currently functional only on am437x-gp-evm, >>>>> + * am33xx-evm and boneblack family. Hence set the DS0 flag >>>>> + */ >>>>> + if (of_machine_is_compatible("ti,am437x-gp-evm") || >>>>> + of_machine_is_compatible("ti,am335x-bone-black") || >>>>> + of_machine_is_compatible("ti,am335x-evm")) >>>>> + suspend_wfi_flags |= WFI_FLAG_DEEP_SLEEP0; >>>> >>>> What about other (out-of-tree) machines which supports DS0 and which >>>> this change would break? >>>> >>>> I think this needs to be a blacklist if anything. >>>> >>>> Please also expand in the commit message why you think this is needed. >> >> Currently when one does echo mem > /sys/power/state on unsuppored >> machines there can be a crash or a hang. So bail out with a message. > > Yes, but why is this unsupported on some machines? Which machines, and > why? Your commit messages should be self-contained and hold the > information needed to determine whether your patch makes sense in the > first place. Okay > >>>> Last, what tree is this against? There's no am43xx_suspend() in >>>> linux-next (and you add compatibles above for am33xx too). >>> >>> Sorry, there is indeed an am43xx_suspend(), but you are adding >>> compatibles for am33xx which use am33xx_suspend(). >> >> am33xx_pm_probe is a common probe function for both am33 and am43. > > Yes, but you add a check for your new flag only to am43xx_suspend(), not > to am33xx_suspend() which is used by the am33xx compatibles you add. Got it. I will add a check there as well. > >> AFAIK for am33 family am335x-evm and am335x-bone-black support Deep >> Sleep mode. For am43 family am43tx-gp-evm alone supports at the moment. > > But these are development boards (EVKs), not SOC families (or > chip revisions). What about all the products that customers to TI who > have bought these SoCs have built? > >> Can you let me know of other am33 machines that support DS0 mode? > > I have a customer who use DS0, whose DTS is not yet in mainline, and > whose setup this patch would break for example. okay > >> I could have simply used ti,am33xx compatible which covers entire am33 >> family but then am33xx-bone (bone white) does not support this mode. > > Yes, and a blacklist would make much more sense for something like this > if where talking about specific boards. > > Also note that your patch doesn't even handle bone-white as you didn't > add a check to am33xx_suspend() as I pointed out above. Tony, Black list is easier here? Regards, Keerthy > > Johan >