Linux-ARM-MSM Archive on lore.kernel.org
 help / color / Atom feed
* [PATCH] clk: qcom: gcc-sdm845: Use floor ops for sdcc clks
@ 2019-08-30 19:51 Stephen Boyd
  2019-08-30 21:34 ` Doug Anderson
  2019-09-09 10:25 ` Stephen Boyd
  0 siblings, 2 replies; 6+ messages in thread
From: Stephen Boyd @ 2019-08-30 19:51 UTC (permalink / raw)
  To: Michael Turquette, Stephen Boyd
  Cc: linux-kernel, linux-clk, linux-arm-msm, Douglas Anderson, Taniya Das

Some MMC cards fail to enumerate properly when inserted into an MMC slot
on sdm845 devices. This is because the clk ops for qcom clks round the
frequency up to the nearest rate instead of down to the nearest rate.
For example, the MMC driver requests a frequency of 52MHz from
clk_set_rate() but the qcom implementation for these clks rounds 52MHz
up to the next supported frequency of 100MHz. The MMC driver could be
modified to request clk rate ranges but for now we can fix this in the
clk driver by changing the rounding policy for this clk to be round down
instead of round up.

Fixes: 06391eddb60a ("clk: qcom: Add Global Clock controller (GCC) driver for SDM845")
Reported-by: Douglas Anderson <dianders@chromium.org>
Cc: Taniya Das <tdas@codeaurora.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---

I suppose we need to do this for all the sdc clks in qcom driver?

 drivers/clk/qcom/gcc-sdm845.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/qcom/gcc-sdm845.c b/drivers/clk/qcom/gcc-sdm845.c
index 7131dcf9b060..95be125c3bdd 100644
--- a/drivers/clk/qcom/gcc-sdm845.c
+++ b/drivers/clk/qcom/gcc-sdm845.c
@@ -685,7 +685,7 @@ static struct clk_rcg2 gcc_sdcc2_apps_clk_src = {
 		.name = "gcc_sdcc2_apps_clk_src",
 		.parent_names = gcc_parent_names_10,
 		.num_parents = 5,
-		.ops = &clk_rcg2_ops,
+		.ops = &clk_rcg2_floor_ops,
 	},
 };
 
@@ -709,7 +709,7 @@ static struct clk_rcg2 gcc_sdcc4_apps_clk_src = {
 		.name = "gcc_sdcc4_apps_clk_src",
 		.parent_names = gcc_parent_names_0,
 		.num_parents = 4,
-		.ops = &clk_rcg2_ops,
+		.ops = &clk_rcg2_floor_ops,
 	},
 };
 
-- 
Sent by a computer through tubes


^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, back to index

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-08-30 19:51 [PATCH] clk: qcom: gcc-sdm845: Use floor ops for sdcc clks Stephen Boyd
2019-08-30 21:34 ` Doug Anderson
2019-09-03 15:52   ` Taniya Das
2019-09-03 22:47     ` Stephen Boyd
2019-09-05  9:22       ` Taniya Das
2019-09-09 10:25 ` Stephen Boyd

Linux-ARM-MSM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-arm-msm/0 linux-arm-msm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-arm-msm linux-arm-msm/ https://lore.kernel.org/linux-arm-msm \
		linux-arm-msm@vger.kernel.org linux-arm-msm@archiver.kernel.org
	public-inbox-index linux-arm-msm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-arm-msm


AGPL code for this site: git clone https://public-inbox.org/ public-inbox