LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Dario Binacchi <dariobin@libero.it>
To: linux-clk@vger.kernel.org
Cc: Dario Binacchi <dariobin@libero.it>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>,
	Gabriel Fernandez <gabriel.fernandez@st.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	linux-stm32@st-md-mailman.stormreply.com
Subject: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs
Date: Sun, 25 Jul 2021 18:07:25 +0200	[thread overview]
Message-ID: <20210725160725.10788-1-dariobin@libero.it> (raw)

Enabling the framebuffer leads to a system hang. Running, as a debug
hack, the store_pan() function in drivers/video/fbdev/core/fbsysfs.c
without taking the console_lock, allows to see the crash backtrace on
the serial line.

~ # echo 0 0 > /sys/class/graphics/fb0/pan

[    9.719414] Unhandled exception: IPSR = 00000005 LR = fffffff1
[    9.726937] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9
[    9.733008] Hardware name: STM32 (Device Tree Support)
[    9.738296] PC is at clk_gate_is_enabled+0x0/0x28
[    9.743426] LR is at stm32f4_pll_div_set_rate+0xf/0x38
[    9.748857] pc : [<0011e4be>]    lr : [<0011f9e3>]    psr: 0100000b
[    9.755373] sp : 00bc7be0  ip : 00000000  fp : 001f3ac4
[    9.760812] r10: 002610d0  r9 : 01efe920  r8 : 00540560
[    9.766269] r7 : 02e7ddb0  r6 : 0173eed8  r5 : 00000000  r4 : 004027c0
[    9.773081] r3 : 0011e4bf  r2 : 02e7ddb0  r1 : 0173eed8  r0 : 1d3267b8
[    9.779911] xPSR: 0100000b
[    9.782719] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9
[    9.788791] Hardware name: STM32 (Device Tree Support)
[    9.794120] [<0000afa1>] (unwind_backtrace) from [<0000a33f>] (show_stack+0xb/0xc)
[    9.802421] [<0000a33f>] (show_stack) from [<0000a8df>] (__invalid_entry+0x4b/0x4c)

The `pll_num' field in the post_div_data configuration contained a wrong
value which also referenced an uninitialized hardware clock when
clk_register_pll_div() was called.

Fixes: 517633ef630e ("clk: stm32f4: Add post divisor for I2S & SAI PLLs")
Signed-off-by: Dario Binacchi <dariobin@libero.it>
Reviewed-by: Gabriel Fernandez <gabriel.fernandez@st.com>

---
I added Gabriel Fernandez's 'Reviewed-by' tag as requested by himself
15 days ago at https://lore.kernel.org/patchwork/patch/1450964/.

Changes in v4:
- Really add Gabriel Fernandez 'Reviewed-by' tag. In version 3 I forgot
  to add the tag.

Changes in v3:
- Add Gabriel Fernandez 'Reviewed-by' tag.

Changes in v2:
- Change  'u8 pll_num' from 'stm32f4_pll_post_div_data' structure into
  'int pll_idx'.

 drivers/clk/clk-stm32f4.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c
index 18117ce5ff85..5c75e3d906c2 100644
--- a/drivers/clk/clk-stm32f4.c
+++ b/drivers/clk/clk-stm32f4.c
@@ -526,7 +526,7 @@ struct stm32f4_pll {
 
 struct stm32f4_pll_post_div_data {
 	int idx;
-	u8 pll_num;
+	int pll_idx;
 	const char *name;
 	const char *parent;
 	u8 flag;
@@ -557,13 +557,13 @@ static const struct clk_div_table post_divr_table[] = {
 
 #define MAX_POST_DIV 3
 static const struct stm32f4_pll_post_div_data  post_div_data[MAX_POST_DIV] = {
-	{ CLK_I2SQ_PDIV, PLL_I2S, "plli2s-q-div", "plli2s-q",
+	{ CLK_I2SQ_PDIV, PLL_VCO_I2S, "plli2s-q-div", "plli2s-q",
 		CLK_SET_RATE_PARENT, STM32F4_RCC_DCKCFGR, 0, 5, 0, NULL},
 
-	{ CLK_SAIQ_PDIV, PLL_SAI, "pllsai-q-div", "pllsai-q",
+	{ CLK_SAIQ_PDIV, PLL_VCO_SAI, "pllsai-q-div", "pllsai-q",
 		CLK_SET_RATE_PARENT, STM32F4_RCC_DCKCFGR, 8, 5, 0, NULL },
 
-	{ NO_IDX, PLL_SAI, "pllsai-r-div", "pllsai-r", CLK_SET_RATE_PARENT,
+	{ NO_IDX, PLL_VCO_SAI, "pllsai-r-div", "pllsai-r", CLK_SET_RATE_PARENT,
 		STM32F4_RCC_DCKCFGR, 16, 2, 0, post_divr_table },
 };
 
@@ -1774,7 +1774,7 @@ static void __init stm32f4_rcc_init(struct device_node *np)
 				post_div->width,
 				post_div->flag_div,
 				post_div->div_table,
-				clks[post_div->pll_num],
+				clks[post_div->pll_idx],
 				&stm32f4_clk_lock);
 
 		if (post_div->idx != NO_IDX)
-- 
2.17.1


             reply	other threads:[~2021-07-25 16:07 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-25 16:07 Dario Binacchi [this message]
2021-07-27  0:22 ` Stephen Boyd
2021-07-28 10:03 ` Dillon Hua
2021-07-29 10:03   ` Dario Binacchi
2021-07-30 19:47     ` Stephen Boyd
2021-07-30 21:22       ` Dario Binacchi
2021-08-01 14:56     ` Dillon Hua
2021-08-01 19:37       ` Dario Binacchi
2021-08-02 22:09         ` Stephen Boyd

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210725160725.10788-1-dariobin@libero.it \
    --to=dariobin@libero.it \
    --cc=alexandre.torgue@foss.st.com \
    --cc=gabriel.fernandez@st.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-stm32@st-md-mailman.stormreply.com \
    --cc=mcoquelin.stm32@gmail.com \
    --cc=mturquette@baylibre.com \
    --cc=sboyd@kernel.org \
    --subject='Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).