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From: Priit Laes <plaes@plaes.org>
To: "Jernej Škrabec" <jernej.skrabec@siol.net>
Cc: maxime.ripard@bootlin.com, wens@csie.org, robh+dt@kernel.org,
	mturquette@baylibre.com, sboyd@kernel.org, airlied@linux.ie,
	architt@codeaurora.org, a.hajda@samsung.com,
	Laurent.pinchart@ideasonboard.com, devicetree@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org,
	dri-devel@lists.freedesktop.org, linux-sunxi@googlegroups.com
Subject: Re: [linux-sunxi] [PATCH v3 02/28] clk: sunxi-ng: Adjust MP clock parent rate when allowed
Date: Mon, 21 Jan 2019 13:34:33 +0000	[thread overview]
Message-ID: <20190121133433.lryqz7ivrj5cxu3g@plaes.org> (raw)
In-Reply-To: <20190121083729.7qsmj7drxvmnjoye@plaes.org>

On Mon, Jan 21, 2019 at 08:37:29AM +0000, Priit Laes wrote:
> On Fri, Jan 18, 2019 at 10:51:10PM +0100, Jernej Škrabec wrote:
> > Dne četrtek, 17. januar 2019 ob 08:24:02 CET je Priit Laes napisal(a):
> > > On Wed, Jan 16, 2019 at 06:00:32PM +0100, Jernej Škrabec wrote:
> > > > Dne sreda, 16. januar 2019 ob 13:09:58 CET je Priit Laes napisal(a):
> > > > > On Thu, Jan 10, 2019 at 06:10:59PM +0100, Jernej Škrabec wrote:
> > > > > > Dne četrtek, 10. januar 2019 ob 10:15:48 CET je Priit Laes napisal(a):
> > > > > > > On Sun, Nov 04, 2018 at 07:26:39PM +0100, Jernej Skrabec wrote:
> > > > > > > > Currently MP clocks don't consider adjusting parent rate even if
> > > > > > > > they
> > > > > > > > are allowed to do so. Such behaviour considerably lowers amount of
> > > > > > > > possible rates, which is very inconvenient when such clock is used
> > > > > > > > for
> > > > > > > > pixel clock, for example.
> > > > > > > > 
> > > > > > > > In order to improve the situation, adjusting parent rate is
> > > > > > > > considered
> > > > > > > > when allowed.
> > > > > > > > 
> > > > > > > > This code is inspired by clk_divider_bestdiv() function, which
> > > > > > > > does
> > > > > > > > basically the same thing for different clock type.
> > > > > > > 
> > > > > > > This patch seems to break the eMMC support on Olinuxino-Lime2-eMMC
> > > > > > > boards:
> > > > > > > 
> > > > > > > EXT4-fs (mmcblk1p4): INFO: recovery required on readonly filesystem
> > > > > > > EXT4-fs (mmcblk1p4): write access will be enabled during recovery
> > > > > > > sunxi-mmc 1c11000.mmc: data error, sending stop command
> > > > > > > sunxi-mmc 1c11000.mmc: send stop command failed
> > > > > > 
> > > > > > I'm not familiar with A20. What is interesting is that emmc clocks
> > > > > > don't
> > > > > > have CLK_SET_RATE_PARENT flag set, so you shouldn't see any
> > > > > > difference.
> > > > > > 
> > > > > > Can you post content of clk_summary with and without this patch?
> > > > > 
> > > > > In both cases I booted from FEL with rootfs on sdcard and tried to mount
> > > > > partition from eMMC to /mnt. With your patch, last step it fails.
> > > > > 
> > > > > pre-patch working:
> > > > > pll-ddr-other[768MHz] -> mmc2[512MHz]. (For some reason ahb-mmc2 is
> > > > > off?)
> > > > > 
> > > > > post-patch not working:
> > > > > pll-periph[600MHz] ->  mmc2[500Mhz], (ahb-mmc2 is enabled)
> > > > > 
> > > > > Also, attached the logs.
> > > > 
> > > > Thanks. Just one more request. Can you enable debug messages in mmc
> > > > driver?
> > > > I'm interested in output of this line:
> > > > 
> > > > dev_dbg(mmc_dev(mmc), "setting clk to %d, rounded %ld\n",
> > > > 
> > > > 		clock, rate);
> > > 
> > > 1c11000 is eMMC:
> > > [snip]
> > > [    1.961644] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.004091] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.020296] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.039917] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.047847] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.055053] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.065256] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.092351] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.168725] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.189403] sunxi-mmc 1c11000.mmc: setting clk to 52000000, rounded
> > > 52000000 [    2.203340] sunxi-mmc 1c11000.mmc: setting clk to 52000000,
> > > rounded 52000000 [    2.211412] sunxi-mmc 1c11000.mmc: setting clk to
> > > 52000000, rounded 52000000 [    4.967865] sunxi-mmc 1c11000.mmc: setting
> > > clk to 52000000, rounded 52000000 [    8.755345] sunxi-mmc 1c11000.mmc:
> > > setting clk to 52000000, rounded 52000000 [    9.082510] sunxi-mmc
> > > 1c11000.mmc: setting clk to 52000000, rounded 52000000
> > > 
> > > Here I tried to mount partition from eMMC...
> > > 
> > > [   72.167311] sunxi-mmc 1c11000.mmc: setting clk to 52000000, rounded
> > > 52000000 [   72.269629] sunxi-mmc 1c11000.mmc: data error, sending stop
> > > command [   73.268999] sunxi-mmc 1c11000.mmc: send stop command failed
> > > [/snip]
> > > 
> > > And clock tree:
> > > [snip]
> > > pll-periph-base                3        3        0  1200000000          0   
> > >  0  50000 pll-periph                  6        6        0   600000000      
> > >    0     0  50000 mmc2                     3        3        0    50000000 
> > >         0     0  50000 mmc2_sample           1        1        0   
> > > 50000000          0   120  50000 mmc2_output           1        1        0 
> > >   50000000          0    60  50000 ahb                     18       18     
> > >   0   300000000          0     0  50000 ahb-mmc2              1        1   
> > >     0   300000000          0     0  50000 [/snip]
> > > 
> > > 
> > > And without patch:
> > > [snip]
> > > [    2.003341] sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000, rounded
> > > 400000 [    2.019479] sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000,
> > > rounded 400000 [    2.039144] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 400000, rounded 400000 [    2.047129] sunxi-mmc 1c11000.mmc: XXX: setting
> > > clk to 400000, rounded 400000 [    2.054324] sunxi-mmc 1c11000.mmc: XXX:
> > > setting clk to 400000, rounded 400000 [    2.064481] sunxi-mmc 1c11000.mmc:
> > > XXX: setting clk to 400000, rounded 400000 [    2.091624] sunxi-mmc
> > > 1c11000.mmc: XXX: setting clk to 400000, rounded 400000 [    2.168067]
> > > sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000, rounded 400000 [   
> > > 2.188239] sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded
> > > 51200000 [    2.202779] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 52000000, rounded 51200000 [    2.210817] sunxi-mmc 1c11000.mmc: XXX:
> > > setting clk to 52000000, rounded 51200000 [    5.103358] sunxi-mmc
> > > 1c11000.mmc: XXX: setting clk to 52000000, rounded 51200000 [    8.950237]
> > > sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded 51200000 [   
> > > 9.376201] sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded
> > > 51200000 [  113.618387] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 52000000, rounded 51200000 [  113.707979] EXT4-fs (mmcblk1p4): recovery
> > > complete
> > > [  113.728162] EXT4-fs (mmcblk1p4): mounted filesystem with ordered data
> > > mode. Opts: (null) [/snip]
> > > 
> > > And clock tree:
> > > [snip]
> > > pll-ddr-base                   2        2        0   768000000          0   
> > >  0  50000 pll-ddr-other               1        1        0   768000000      
> > >    0     0  50000 mmc2                     0        0        0    51200000 
> > >         0     0  50000 mmc2_sample           0        0        0   
> > > 51200000          0   120  50000 mmc2_output           0        0        0 
> > >   51200000          0    72  50000 [/snip]
> > > 
> > 
> > It seems to me that clock rate is set properly. It's even better than before 
> > since there is no error between wanted and real clock. I bet that if you call 
> > clk_get_rate() directly behind clk_set_rate() in mmc driver, you'll get 
> > correct value.
> > 
> > However, it seems that at some point some other peripheral changes it's parent 
> > clock rate, which inadvertely changes emmc2 clock rate too. The only possible 
> > clock which could interfere is sata. Can you disable driver in you kernel 
> > config and try again?
> 
> OK, tried following things in succession, but SATA disabling does not work:
> 
> a) Marked all ahci stuff in devicetree as disabled
> b) Disable CONFIG_AHCI_SUNXI in kernel
> c) Even disabled SATA stuff in u-boot

But it works, when I allow mmc2 clock to set parent rate:

pll-periph-base                3        3        0   312000000          0     0  50000
   mbus                        1        1        0    78000000          0     0  50000
   pll-periph-sata             1        1        0    26000000          0     0  50000
      sata                     1        1        0    26000000          0     0  50000
   pll-periph                  5        5        0   156000000          0     0  50000
      mmc2                     0        0        0    52000000          0     0  50000
         mmc2_sample           0        0        0    52000000          0   120  50000
         mmc2_output           0        0        0    52000000          0   120  50000
      mmc0                     0        0        0    39000000          0     0  50000
         mmc0_sample           0        0        0    39000000          0    90  50000
         mmc0_output           0        0        0    39000000          0    90  50000


Now, what I don't understand is why the `enable count` does not increase :(

---
diff --git a/drivers/clk/sunxi-ng/ccu-sun4i-a10.c b/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
index 129ebd2588fd..605e13b4ef90 100644
--- a/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
+++ b/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
@@ -498,7 +498,7 @@ static SUNXI_CCU_MP_WITH_MUX_GATE(mmc2_clk, "mmc2", mod0_default_parents, 0x090,
                                  16, 2,        /* P */
                                  24, 2,        /* mux */
                                  BIT(31),      /* gate */
-                                 0);
+                                 CLK_SET_RATE_PARENT);
 
 /* MMC output and sample clocks are not present on A10 */
 static SUNXI_CCU_PHASE(mmc2_output_clk, "mmc2_output", "mmc2",


> 
> > 
> > Best regards,
> > Jernej
> 
> -- 
> You received this message because you are subscribed to the Google Groups "linux-sunxi" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscribe@googlegroups.com.
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WARNING: multiple messages have this Message-ID (diff)
From: Priit Laes <plaes-q/aMd4JkU83YtjvyW6yDsg@public.gmane.org>
To: "Jernej Škrabec" <jernej.skrabec-gGgVlfcn5nU@public.gmane.org>
Cc: maxime.ripard-LDxbnhwyfcJBDgjK7y7TUQ@public.gmane.org,
	wens-jdAy2FN1RRM@public.gmane.org,
	robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org,
	mturquette-rdvid1DuHRBWk0Htik3J/w@public.gmane.org,
	sboyd-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org,
	airlied-cv59FeDIM0c@public.gmane.org,
	architt-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org,
	a.hajda-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org,
	Laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org,
	devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-clk-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org,
	linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
Subject: Re: [PATCH v3 02/28] clk: sunxi-ng: Adjust MP clock parent rate when allowed
Date: Mon, 21 Jan 2019 13:34:33 +0000	[thread overview]
Message-ID: <20190121133433.lryqz7ivrj5cxu3g@plaes.org> (raw)
In-Reply-To: <20190121083729.7qsmj7drxvmnjoye-q/aMd4JkU83YtjvyW6yDsg@public.gmane.org>

On Mon, Jan 21, 2019 at 08:37:29AM +0000, Priit Laes wrote:
> On Fri, Jan 18, 2019 at 10:51:10PM +0100, Jernej Škrabec wrote:
> > Dne četrtek, 17. januar 2019 ob 08:24:02 CET je Priit Laes napisal(a):
> > > On Wed, Jan 16, 2019 at 06:00:32PM +0100, Jernej Škrabec wrote:
> > > > Dne sreda, 16. januar 2019 ob 13:09:58 CET je Priit Laes napisal(a):
> > > > > On Thu, Jan 10, 2019 at 06:10:59PM +0100, Jernej Škrabec wrote:
> > > > > > Dne četrtek, 10. januar 2019 ob 10:15:48 CET je Priit Laes napisal(a):
> > > > > > > On Sun, Nov 04, 2018 at 07:26:39PM +0100, Jernej Skrabec wrote:
> > > > > > > > Currently MP clocks don't consider adjusting parent rate even if
> > > > > > > > they
> > > > > > > > are allowed to do so. Such behaviour considerably lowers amount of
> > > > > > > > possible rates, which is very inconvenient when such clock is used
> > > > > > > > for
> > > > > > > > pixel clock, for example.
> > > > > > > > 
> > > > > > > > In order to improve the situation, adjusting parent rate is
> > > > > > > > considered
> > > > > > > > when allowed.
> > > > > > > > 
> > > > > > > > This code is inspired by clk_divider_bestdiv() function, which
> > > > > > > > does
> > > > > > > > basically the same thing for different clock type.
> > > > > > > 
> > > > > > > This patch seems to break the eMMC support on Olinuxino-Lime2-eMMC
> > > > > > > boards:
> > > > > > > 
> > > > > > > EXT4-fs (mmcblk1p4): INFO: recovery required on readonly filesystem
> > > > > > > EXT4-fs (mmcblk1p4): write access will be enabled during recovery
> > > > > > > sunxi-mmc 1c11000.mmc: data error, sending stop command
> > > > > > > sunxi-mmc 1c11000.mmc: send stop command failed
> > > > > > 
> > > > > > I'm not familiar with A20. What is interesting is that emmc clocks
> > > > > > don't
> > > > > > have CLK_SET_RATE_PARENT flag set, so you shouldn't see any
> > > > > > difference.
> > > > > > 
> > > > > > Can you post content of clk_summary with and without this patch?
> > > > > 
> > > > > In both cases I booted from FEL with rootfs on sdcard and tried to mount
> > > > > partition from eMMC to /mnt. With your patch, last step it fails.
> > > > > 
> > > > > pre-patch working:
> > > > > pll-ddr-other[768MHz] -> mmc2[512MHz]. (For some reason ahb-mmc2 is
> > > > > off?)
> > > > > 
> > > > > post-patch not working:
> > > > > pll-periph[600MHz] ->  mmc2[500Mhz], (ahb-mmc2 is enabled)
> > > > > 
> > > > > Also, attached the logs.
> > > > 
> > > > Thanks. Just one more request. Can you enable debug messages in mmc
> > > > driver?
> > > > I'm interested in output of this line:
> > > > 
> > > > dev_dbg(mmc_dev(mmc), "setting clk to %d, rounded %ld\n",
> > > > 
> > > > 		clock, rate);
> > > 
> > > 1c11000 is eMMC:
> > > [snip]
> > > [    1.961644] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.004091] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.020296] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.039917] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.047847] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.055053] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.065256] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.092351] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.168725] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.189403] sunxi-mmc 1c11000.mmc: setting clk to 52000000, rounded
> > > 52000000 [    2.203340] sunxi-mmc 1c11000.mmc: setting clk to 52000000,
> > > rounded 52000000 [    2.211412] sunxi-mmc 1c11000.mmc: setting clk to
> > > 52000000, rounded 52000000 [    4.967865] sunxi-mmc 1c11000.mmc: setting
> > > clk to 52000000, rounded 52000000 [    8.755345] sunxi-mmc 1c11000.mmc:
> > > setting clk to 52000000, rounded 52000000 [    9.082510] sunxi-mmc
> > > 1c11000.mmc: setting clk to 52000000, rounded 52000000
> > > 
> > > Here I tried to mount partition from eMMC...
> > > 
> > > [   72.167311] sunxi-mmc 1c11000.mmc: setting clk to 52000000, rounded
> > > 52000000 [   72.269629] sunxi-mmc 1c11000.mmc: data error, sending stop
> > > command [   73.268999] sunxi-mmc 1c11000.mmc: send stop command failed
> > > [/snip]
> > > 
> > > And clock tree:
> > > [snip]
> > > pll-periph-base                3        3        0  1200000000          0   
> > >  0  50000 pll-periph                  6        6        0   600000000      
> > >    0     0  50000 mmc2                     3        3        0    50000000 
> > >         0     0  50000 mmc2_sample           1        1        0   
> > > 50000000          0   120  50000 mmc2_output           1        1        0 
> > >   50000000          0    60  50000 ahb                     18       18     
> > >   0   300000000          0     0  50000 ahb-mmc2              1        1   
> > >     0   300000000          0     0  50000 [/snip]
> > > 
> > > 
> > > And without patch:
> > > [snip]
> > > [    2.003341] sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000, rounded
> > > 400000 [    2.019479] sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000,
> > > rounded 400000 [    2.039144] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 400000, rounded 400000 [    2.047129] sunxi-mmc 1c11000.mmc: XXX: setting
> > > clk to 400000, rounded 400000 [    2.054324] sunxi-mmc 1c11000.mmc: XXX:
> > > setting clk to 400000, rounded 400000 [    2.064481] sunxi-mmc 1c11000.mmc:
> > > XXX: setting clk to 400000, rounded 400000 [    2.091624] sunxi-mmc
> > > 1c11000.mmc: XXX: setting clk to 400000, rounded 400000 [    2.168067]
> > > sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000, rounded 400000 [   
> > > 2.188239] sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded
> > > 51200000 [    2.202779] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 52000000, rounded 51200000 [    2.210817] sunxi-mmc 1c11000.mmc: XXX:
> > > setting clk to 52000000, rounded 51200000 [    5.103358] sunxi-mmc
> > > 1c11000.mmc: XXX: setting clk to 52000000, rounded 51200000 [    8.950237]
> > > sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded 51200000 [   
> > > 9.376201] sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded
> > > 51200000 [  113.618387] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 52000000, rounded 51200000 [  113.707979] EXT4-fs (mmcblk1p4): recovery
> > > complete
> > > [  113.728162] EXT4-fs (mmcblk1p4): mounted filesystem with ordered data
> > > mode. Opts: (null) [/snip]
> > > 
> > > And clock tree:
> > > [snip]
> > > pll-ddr-base                   2        2        0   768000000          0   
> > >  0  50000 pll-ddr-other               1        1        0   768000000      
> > >    0     0  50000 mmc2                     0        0        0    51200000 
> > >         0     0  50000 mmc2_sample           0        0        0   
> > > 51200000          0   120  50000 mmc2_output           0        0        0 
> > >   51200000          0    72  50000 [/snip]
> > > 
> > 
> > It seems to me that clock rate is set properly. It's even better than before 
> > since there is no error between wanted and real clock. I bet that if you call 
> > clk_get_rate() directly behind clk_set_rate() in mmc driver, you'll get 
> > correct value.
> > 
> > However, it seems that at some point some other peripheral changes it's parent 
> > clock rate, which inadvertely changes emmc2 clock rate too. The only possible 
> > clock which could interfere is sata. Can you disable driver in you kernel 
> > config and try again?
> 
> OK, tried following things in succession, but SATA disabling does not work:
> 
> a) Marked all ahci stuff in devicetree as disabled
> b) Disable CONFIG_AHCI_SUNXI in kernel
> c) Even disabled SATA stuff in u-boot

But it works, when I allow mmc2 clock to set parent rate:

pll-periph-base                3        3        0   312000000          0     0  50000
   mbus                        1        1        0    78000000          0     0  50000
   pll-periph-sata             1        1        0    26000000          0     0  50000
      sata                     1        1        0    26000000          0     0  50000
   pll-periph                  5        5        0   156000000          0     0  50000
      mmc2                     0        0        0    52000000          0     0  50000
         mmc2_sample           0        0        0    52000000          0   120  50000
         mmc2_output           0        0        0    52000000          0   120  50000
      mmc0                     0        0        0    39000000          0     0  50000
         mmc0_sample           0        0        0    39000000          0    90  50000
         mmc0_output           0        0        0    39000000          0    90  50000


Now, what I don't understand is why the `enable count` does not increase :(

---
diff --git a/drivers/clk/sunxi-ng/ccu-sun4i-a10.c b/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
index 129ebd2588fd..605e13b4ef90 100644
--- a/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
+++ b/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
@@ -498,7 +498,7 @@ static SUNXI_CCU_MP_WITH_MUX_GATE(mmc2_clk, "mmc2", mod0_default_parents, 0x090,
                                  16, 2,        /* P */
                                  24, 2,        /* mux */
                                  BIT(31),      /* gate */
-                                 0);
+                                 CLK_SET_RATE_PARENT);
 
 /* MMC output and sample clocks are not present on A10 */
 static SUNXI_CCU_PHASE(mmc2_output_clk, "mmc2_output", "mmc2",


> 
> > 
> > Best regards,
> > Jernej
> 
> -- 
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WARNING: multiple messages have this Message-ID (diff)
From: Priit Laes <plaes@plaes.org>
To: "Jernej Škrabec" <jernej.skrabec@siol.net>
Cc: linux-arm-kernel@lists.infradead.org, airlied@linux.ie,
	architt@codeaurora.org, a.hajda@samsung.com,
	maxime.ripard@bootlin.com, mturquette@baylibre.com,
	linux-sunxi@googlegroups.com, linux-kernel@vger.kernel.org,
	dri-devel@lists.freedesktop.org, sboyd@kernel.org, wens@csie.org,
	robh+dt@kernel.org, Laurent.pinchart@ideasonboard.com,
	linux-clk@vger.kernel.org, devicetree@vger.kernel.org
Subject: Re: [linux-sunxi] [PATCH v3 02/28] clk: sunxi-ng: Adjust MP clock parent rate when allowed
Date: Mon, 21 Jan 2019 13:34:33 +0000	[thread overview]
Message-ID: <20190121133433.lryqz7ivrj5cxu3g@plaes.org> (raw)
In-Reply-To: <20190121083729.7qsmj7drxvmnjoye@plaes.org>

On Mon, Jan 21, 2019 at 08:37:29AM +0000, Priit Laes wrote:
> On Fri, Jan 18, 2019 at 10:51:10PM +0100, Jernej Škrabec wrote:
> > Dne četrtek, 17. januar 2019 ob 08:24:02 CET je Priit Laes napisal(a):
> > > On Wed, Jan 16, 2019 at 06:00:32PM +0100, Jernej Škrabec wrote:
> > > > Dne sreda, 16. januar 2019 ob 13:09:58 CET je Priit Laes napisal(a):
> > > > > On Thu, Jan 10, 2019 at 06:10:59PM +0100, Jernej Škrabec wrote:
> > > > > > Dne četrtek, 10. januar 2019 ob 10:15:48 CET je Priit Laes napisal(a):
> > > > > > > On Sun, Nov 04, 2018 at 07:26:39PM +0100, Jernej Skrabec wrote:
> > > > > > > > Currently MP clocks don't consider adjusting parent rate even if
> > > > > > > > they
> > > > > > > > are allowed to do so. Such behaviour considerably lowers amount of
> > > > > > > > possible rates, which is very inconvenient when such clock is used
> > > > > > > > for
> > > > > > > > pixel clock, for example.
> > > > > > > > 
> > > > > > > > In order to improve the situation, adjusting parent rate is
> > > > > > > > considered
> > > > > > > > when allowed.
> > > > > > > > 
> > > > > > > > This code is inspired by clk_divider_bestdiv() function, which
> > > > > > > > does
> > > > > > > > basically the same thing for different clock type.
> > > > > > > 
> > > > > > > This patch seems to break the eMMC support on Olinuxino-Lime2-eMMC
> > > > > > > boards:
> > > > > > > 
> > > > > > > EXT4-fs (mmcblk1p4): INFO: recovery required on readonly filesystem
> > > > > > > EXT4-fs (mmcblk1p4): write access will be enabled during recovery
> > > > > > > sunxi-mmc 1c11000.mmc: data error, sending stop command
> > > > > > > sunxi-mmc 1c11000.mmc: send stop command failed
> > > > > > 
> > > > > > I'm not familiar with A20. What is interesting is that emmc clocks
> > > > > > don't
> > > > > > have CLK_SET_RATE_PARENT flag set, so you shouldn't see any
> > > > > > difference.
> > > > > > 
> > > > > > Can you post content of clk_summary with and without this patch?
> > > > > 
> > > > > In both cases I booted from FEL with rootfs on sdcard and tried to mount
> > > > > partition from eMMC to /mnt. With your patch, last step it fails.
> > > > > 
> > > > > pre-patch working:
> > > > > pll-ddr-other[768MHz] -> mmc2[512MHz]. (For some reason ahb-mmc2 is
> > > > > off?)
> > > > > 
> > > > > post-patch not working:
> > > > > pll-periph[600MHz] ->  mmc2[500Mhz], (ahb-mmc2 is enabled)
> > > > > 
> > > > > Also, attached the logs.
> > > > 
> > > > Thanks. Just one more request. Can you enable debug messages in mmc
> > > > driver?
> > > > I'm interested in output of this line:
> > > > 
> > > > dev_dbg(mmc_dev(mmc), "setting clk to %d, rounded %ld\n",
> > > > 
> > > > 		clock, rate);
> > > 
> > > 1c11000 is eMMC:
> > > [snip]
> > > [    1.961644] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.004091] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.020296] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.039917] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.047847] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.055053] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.065256] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.092351] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.168725] sunxi-mmc 1c11000.mmc: setting clk to 400000, rounded 400000
> > > [    2.189403] sunxi-mmc 1c11000.mmc: setting clk to 52000000, rounded
> > > 52000000 [    2.203340] sunxi-mmc 1c11000.mmc: setting clk to 52000000,
> > > rounded 52000000 [    2.211412] sunxi-mmc 1c11000.mmc: setting clk to
> > > 52000000, rounded 52000000 [    4.967865] sunxi-mmc 1c11000.mmc: setting
> > > clk to 52000000, rounded 52000000 [    8.755345] sunxi-mmc 1c11000.mmc:
> > > setting clk to 52000000, rounded 52000000 [    9.082510] sunxi-mmc
> > > 1c11000.mmc: setting clk to 52000000, rounded 52000000
> > > 
> > > Here I tried to mount partition from eMMC...
> > > 
> > > [   72.167311] sunxi-mmc 1c11000.mmc: setting clk to 52000000, rounded
> > > 52000000 [   72.269629] sunxi-mmc 1c11000.mmc: data error, sending stop
> > > command [   73.268999] sunxi-mmc 1c11000.mmc: send stop command failed
> > > [/snip]
> > > 
> > > And clock tree:
> > > [snip]
> > > pll-periph-base                3        3        0  1200000000          0   
> > >  0  50000 pll-periph                  6        6        0   600000000      
> > >    0     0  50000 mmc2                     3        3        0    50000000 
> > >         0     0  50000 mmc2_sample           1        1        0   
> > > 50000000          0   120  50000 mmc2_output           1        1        0 
> > >   50000000          0    60  50000 ahb                     18       18     
> > >   0   300000000          0     0  50000 ahb-mmc2              1        1   
> > >     0   300000000          0     0  50000 [/snip]
> > > 
> > > 
> > > And without patch:
> > > [snip]
> > > [    2.003341] sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000, rounded
> > > 400000 [    2.019479] sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000,
> > > rounded 400000 [    2.039144] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 400000, rounded 400000 [    2.047129] sunxi-mmc 1c11000.mmc: XXX: setting
> > > clk to 400000, rounded 400000 [    2.054324] sunxi-mmc 1c11000.mmc: XXX:
> > > setting clk to 400000, rounded 400000 [    2.064481] sunxi-mmc 1c11000.mmc:
> > > XXX: setting clk to 400000, rounded 400000 [    2.091624] sunxi-mmc
> > > 1c11000.mmc: XXX: setting clk to 400000, rounded 400000 [    2.168067]
> > > sunxi-mmc 1c11000.mmc: XXX: setting clk to 400000, rounded 400000 [   
> > > 2.188239] sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded
> > > 51200000 [    2.202779] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 52000000, rounded 51200000 [    2.210817] sunxi-mmc 1c11000.mmc: XXX:
> > > setting clk to 52000000, rounded 51200000 [    5.103358] sunxi-mmc
> > > 1c11000.mmc: XXX: setting clk to 52000000, rounded 51200000 [    8.950237]
> > > sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded 51200000 [   
> > > 9.376201] sunxi-mmc 1c11000.mmc: XXX: setting clk to 52000000, rounded
> > > 51200000 [  113.618387] sunxi-mmc 1c11000.mmc: XXX: setting clk to
> > > 52000000, rounded 51200000 [  113.707979] EXT4-fs (mmcblk1p4): recovery
> > > complete
> > > [  113.728162] EXT4-fs (mmcblk1p4): mounted filesystem with ordered data
> > > mode. Opts: (null) [/snip]
> > > 
> > > And clock tree:
> > > [snip]
> > > pll-ddr-base                   2        2        0   768000000          0   
> > >  0  50000 pll-ddr-other               1        1        0   768000000      
> > >    0     0  50000 mmc2                     0        0        0    51200000 
> > >         0     0  50000 mmc2_sample           0        0        0   
> > > 51200000          0   120  50000 mmc2_output           0        0        0 
> > >   51200000          0    72  50000 [/snip]
> > > 
> > 
> > It seems to me that clock rate is set properly. It's even better than before 
> > since there is no error between wanted and real clock. I bet that if you call 
> > clk_get_rate() directly behind clk_set_rate() in mmc driver, you'll get 
> > correct value.
> > 
> > However, it seems that at some point some other peripheral changes it's parent 
> > clock rate, which inadvertely changes emmc2 clock rate too. The only possible 
> > clock which could interfere is sata. Can you disable driver in you kernel 
> > config and try again?
> 
> OK, tried following things in succession, but SATA disabling does not work:
> 
> a) Marked all ahci stuff in devicetree as disabled
> b) Disable CONFIG_AHCI_SUNXI in kernel
> c) Even disabled SATA stuff in u-boot

But it works, when I allow mmc2 clock to set parent rate:

pll-periph-base                3        3        0   312000000          0     0  50000
   mbus                        1        1        0    78000000          0     0  50000
   pll-periph-sata             1        1        0    26000000          0     0  50000
      sata                     1        1        0    26000000          0     0  50000
   pll-periph                  5        5        0   156000000          0     0  50000
      mmc2                     0        0        0    52000000          0     0  50000
         mmc2_sample           0        0        0    52000000          0   120  50000
         mmc2_output           0        0        0    52000000          0   120  50000
      mmc0                     0        0        0    39000000          0     0  50000
         mmc0_sample           0        0        0    39000000          0    90  50000
         mmc0_output           0        0        0    39000000          0    90  50000


Now, what I don't understand is why the `enable count` does not increase :(

---
diff --git a/drivers/clk/sunxi-ng/ccu-sun4i-a10.c b/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
index 129ebd2588fd..605e13b4ef90 100644
--- a/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
+++ b/drivers/clk/sunxi-ng/ccu-sun4i-a10.c
@@ -498,7 +498,7 @@ static SUNXI_CCU_MP_WITH_MUX_GATE(mmc2_clk, "mmc2", mod0_default_parents, 0x090,
                                  16, 2,        /* P */
                                  24, 2,        /* mux */
                                  BIT(31),      /* gate */
-                                 0);
+                                 CLK_SET_RATE_PARENT);
 
 /* MMC output and sample clocks are not present on A10 */
 static SUNXI_CCU_PHASE(mmc2_output_clk, "mmc2_output", "mmc2",


> 
> > 
> > Best regards,
> > Jernej
> 
> -- 
> You received this message because you are subscribed to the Google Groups "linux-sunxi" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscribe@googlegroups.com.
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  reply	other threads:[~2019-01-21 13:34 UTC|newest]

Thread overview: 126+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-04 18:26 [PATCH v3 00/28] Allwinner H6 DE3 and HDMI support Jernej Skrabec
2018-11-04 18:26 ` Jernej Skrabec
2018-11-04 18:26 ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 01/28] dt-bindings: bus: add H6 DE3 bus binding Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 02/28] clk: sunxi-ng: Adjust MP clock parent rate when allowed Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2019-01-10  9:15   ` [linux-sunxi] " Priit Laes
2019-01-10  9:15     ` Priit Laes
2019-01-10 17:10     ` Jernej Škrabec
2019-01-10 17:10       ` Jernej Škrabec
2019-01-10 17:10       ` Jernej Škrabec
2019-01-16 12:09       ` [linux-sunxi] " Priit Laes
2019-01-16 12:09         ` Priit Laes
2019-01-16 17:00         ` Jernej Škrabec
2019-01-16 17:00           ` Jernej Škrabec
2019-01-16 17:00           ` Jernej Škrabec
2019-01-17  7:24           ` [linux-sunxi] " Priit Laes
2019-01-17  7:24             ` Priit Laes
2019-01-17  7:24             ` Priit Laes
2019-01-18 21:51             ` [linux-sunxi] " Jernej Škrabec
2019-01-18 21:51               ` Jernej Škrabec
2019-01-18 21:51               ` Jernej Škrabec
2019-01-21  8:37               ` [linux-sunxi] " Priit Laes
2019-01-21  8:37                 ` Priit Laes
2019-01-21 13:34                 ` Priit Laes [this message]
2019-01-21 13:34                   ` Priit Laes
2019-01-21 13:34                   ` Priit Laes
2019-01-21 18:13                   ` [linux-sunxi] " Jernej Škrabec
2019-01-21 18:13                     ` Jernej Škrabec
2019-03-19 10:34                     ` Priit Laes
2019-03-19 10:34                       ` Priit Laes
2019-03-19 10:34                       ` Priit Laes
2018-11-04 18:26 ` [PATCH v3 03/28] clk: sunxi-ng: Use u64 for calculation of NM rate Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 04/28] clk: sunxi-ng: h6: Set video PLLs limits Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 05/28] dt-bindings: clock: sun8i-de2: Add H6 DE3 clock description Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 06/28] clk: sunxi-ng: Add support for H6 DE3 clocks Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 07/28] dt-bindings: display: sun4i-drm: Add H6 display engine compatibles Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 08/28] drm/sun4i: Add compatible for H6 display engine Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 09/28] drm/sun4i: Rework DE2 register defines Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 10/28] drm/sun4i: Fix DE2 mixer size Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 11/28] drm/sun4i: Disable unused DE2 sub-engines Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 12/28] drm/sun4i: Add basic support for DE3 Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 13/28] drm/sun4i: Add support for H6 DE3 mixer 0 Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 14/28] drm/bridge/synopsys: dw-hdmi: Enable workaround for v2.12a Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 15/28] drm/sun4i: Not all DW HDMI controllers has scrambled addresses Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 16/28] drm/sun4i: dw-hdmi: Make mode_valid function configurable Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 17/28] drm/sun4i: dw-hdmi: Add quirk for setting TMDS clock Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 18/28] dt-bindings: display: sunxi: add DT binding for Allwinner H6 DW HDMI Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 19/28] drm/sun4i: Add support for H6 DW HDMI controller Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 20/28] drm/sun4i: dw-hdmi-phy: Reorder quirks by family Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 21/28] drm/sun4i: Add support for Synopsys HDMI PHY Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26 ` [PATCH v3 22/28] drm/sun4i: Add support for H6 " Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:26   ` Jernej Skrabec
2018-11-04 18:27 ` [PATCH v3 23/28] drm/sun4i: Initialize registers in tcon-top driver Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27 ` [PATCH v3 24/28] drm: sun4i: add quirks for TCON TOP Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27 ` [PATCH v3 25/28] dt-bindings: display: sun4i-drm: document H6 " Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27 ` [PATCH v3 26/28] drm: sun4i: add support for " Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27 ` [PATCH v3 27/28] arm64: dts: allwinner: h6: Add HDMI pipeline Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27 ` [PATCH v3 28/28] arm64: dts: allwinner: h6: Enable HDMI output on Pine H64 board Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-04 18:27   ` Jernej Skrabec
2018-11-05  9:43 ` [PATCH v3 00/28] Allwinner H6 DE3 and HDMI support Maxime Ripard
2018-11-05  9:43   ` Maxime Ripard
2018-11-06 15:54   ` Jernej Škrabec
2018-11-06 15:54     ` Jernej Škrabec
2018-11-06 15:54     ` Jernej Škrabec
2018-11-06 17:20   ` Jernej Škrabec
2018-11-06 17:20     ` Jernej Škrabec
2018-11-06 17:20     ` Jernej Škrabec
2018-11-07  9:44     ` Maxime Ripard
2018-11-07  9:44       ` Maxime Ripard
2018-11-07  9:44       ` Maxime Ripard
2018-12-03 18:09   ` Jernej Škrabec
2018-12-03 18:09     ` Jernej Škrabec
2018-12-03 18:09     ` Jernej Škrabec
2018-12-04  8:29     ` Maxime Ripard
2018-12-04  8:29       ` Maxime Ripard
2018-12-04  8:29       ` Maxime Ripard

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