Re: [linux-sunxi] [PATCH v3 02/28] clk: sunxi-ng: Adjust MP clock parent... | linux-arm-kernel

quoted

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);

Just wondering what it should be.

Best regards,
Jernej


Best regards,
Jernej

$ git bisect log
git bisect start
# good: [3df407b2a5346db1c48809706ece7a8616c79e0b] mmc:
dw_mmc-bluefield:
simplify the probe() function git bisect good
3df407b2a5346db1c48809706ece7a8616c79e0b
# bad: [00d59fde8532b2d42e80909d2e58678755e04da9] Merge tag 'mmc-v4.21'
of
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc git bisect bad
00d59fde8532b2d42e80909d2e58678755e04da9
# good: [01e421feec0817bb3141eaae4c517410d193d440] Merge branch 'fixes'
into next git bisect good 01e421feec0817bb3141eaae4c517410d193d440
# bad: [1eefdec18eded41833401cfd64749643ff72e7da] Merge branch
'locking-core-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip git bisect bad
1eefdec18eded41833401cfd64749643ff72e7da
# good: [eaa76499711535fd64d747cc4ef0d78ab0fd41c6] Merge tag
'mtd/for-4.21'
of git://git.infradead.org/linux-mtd git bisect good
eaa76499711535fd64d747cc4ef0d78ab0fd41c6
# good: [4e4390ad067a61ce4e7607bd0df31f19a4caa36a] Merge tag
'leds-for-4.21-rc1' of
git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds
git
bisect good 4e4390ad067a61ce4e7607bd0df31f19a4caa36a
# bad: [c2f1f3e0e17d94ab0c66d83e669492cb9e9a3698] Merge
git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next git
bisect
bad c2f1f3e0e17d94ab0c66d83e669492cb9e9a3698
# bad: [e4b99d415c3908581d4703203e1e805f043a3e71] Merge branch
'irq-core-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip git bisect bad
e4b99d415c3908581d4703203e1e805f043a3e71
# bad: [ffe05540d18013db62c43627836a3638e9a2c7aa] Merge branches
'clk-renesas', 'clk-allwinner', 'clk-tegra', 'clk-meson' and
'clk-rockchip'
into clk-next git bisect bad ffe05540d18013db62c43627836a3638e9a2c7aa
# good: [1a501c8defe950571316d5ddd917bf44f5ed7bd4] Merge branches
'clk-managed-registration', 'clk-spdx', 'clk-remove-basic' and
'clk-ops-const' into clk-next git bisect good
1a501c8defe950571316d5ddd917bf44f5ed7bd4
# good: [e74581b79ddd9b49b8c61e2791fc4dffc0245afb] Merge tag
'meson-clk-4.21-2' of https://github.com/BayLibre/clk-meson into
clk-meson
git bisect good e74581b79ddd9b49b8c61e2791fc4dffc0245afb
# good: [60baf75e3f5b76043c25328ac0c5320aaef5ea41] Merge tag
'clk-renesas-for-v4.21-tag2' of
git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers into
clk-renesas git bisect good 60baf75e3f5b76043c25328ac0c5320aaef5ea41
# bad: [a41f85b6017ee20952a60e4330bcae2527fe2c2a] Merge tag
'sunxi-clk-for-4.21' of
https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into
clk-allwinner git bisect bad a41f85b6017ee20952a60e4330bcae2527fe2c2a
# bad: [ee678706e46d0d185c27cc214ad97828e0643159] clk: sunxi-ng: a64:
Fix
gate bit of DSI DPHY git bisect bad
ee678706e46d0d185c27cc214ad97828e0643159
# bad: [65b6657672388b72822e0367f06d41c1e3ffb5bb] clk: sunxi-ng: Use u64
for calculation of NM rate git bisect bad
65b6657672388b72822e0367f06d41c1e3ffb5bb
# good: [db7548934603d9eda12649dff97ea5c29884405d] clk: sunxi-ng:
sun50i:
h6: Fix MMC clock mux width git bisect good
db7548934603d9eda12649dff97ea5c29884405d
# bad: [3f790433c3cb27ecaf2ca0e07ac25964e4fd9f15] clk: sunxi-ng: Adjust
MP
clock parent rate when allowed git bisect bad
3f790433c3cb27ecaf2ca0e07ac25964e4fd9f15
# first bad commit: [3f790433c3cb27ecaf2ca0e07ac25964e4fd9f15] clk:
sunxi-ng: Adjust MP clock parent rate when allowed

Signed-off-by: Jernej Skrabec <redacted>
---

 drivers/clk/sunxi-ng/ccu_mp.c | 64
 +++++++++++++++++++++++++++++++++--
 1 file changed, 62 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/sunxi-ng/ccu_mp.c
b/drivers/clk/sunxi-ng/ccu_mp.c
index 5d0af4051737..0357349eb767 100644
--- a/drivers/clk/sunxi-ng/ccu_mp.c
+++ b/drivers/clk/sunxi-ng/ccu_mp.c
@@ -40,6 +40,61 @@ static void ccu_mp_find_best(unsigned long parent,
unsigned long rate,>

 	*p = best_p;
 
 }

+static unsigned long ccu_mp_find_best_with_parent_adj(struct clk_hw
*hw,
+
unsigned long *parent,

+
unsigned long rate,

+
unsigned int max_m,

+
unsigned int max_p)

+{
+	unsigned long parent_rate_saved;
+	unsigned long parent_rate, now;
+	unsigned long best_rate = 0;
+	unsigned int _m, _p, div;
+	unsigned long maxdiv;
+
+	parent_rate_saved = *parent;
+
+	/*
+	 * The maximum divider we can use without overflowing
+	 * unsigned long in rate * m * p below
+	 */
+	maxdiv = max_m * max_p;
+	maxdiv = min(ULONG_MAX / rate, maxdiv);
+
+	for (_p = 1; _p <= max_p; _p <<= 1) {
+		for (_m = 1; _m <= max_m; _m++) {
+			div = _m * _p;
+
+			if (div > maxdiv)
+				break;
+
+			if (rate * div == parent_rate_saved) {
+				/*
+				 * It's the most ideal case if
the requested

+				 * rate can be divided from
parent clock without

+				 * needing to change parent 
rate,
so return the

+				 * divider immediately.
+				 */
+				*parent = parent_rate_saved;
+				return rate;
+			}
+
+			parent_rate = clk_hw_round_rate(hw, rate *
div);

+			now = parent_rate / div;
+
+			if (now <= rate && now > best_rate) {
+				best_rate = now;
+				*parent = parent_rate;
+
+				if (now == rate)
+					return rate;
+			}
+		}
+	}
+
+	return best_rate;
+}
+

 static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux,
 
 				       struct clk_hw *hw,
 				       unsigned long
*parent_rate,

@@ -56,8 +111,13 @@ static unsigned long ccu_mp_round_rate(struct
ccu_mux_internal *mux,>

 	max_m = cmp->m.max ?: 1 << cmp->m.width;
 	max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);

-	ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p);
-	rate = *parent_rate / p / m;
+	if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) {
+		ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m,
&p);

+		rate = *parent_rate / p / m;
+	} else {
+		rate = ccu_mp_find_best_with_parent_adj(hw, 
parent_rate,
rate,

+
max_m, max_p);

+	}

 	if (cmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
 	
 		rate /= cmp->fixed_post_div;




_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

`h`	back out one level
`j`	next message in thread
`k`	previous message in thread
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help