2021-07-25 16:11:19

by Dario Binacchi

[permalink] [raw]
Subject: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

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 <[email protected]>
Reviewed-by: Gabriel Fernandez <[email protected]>

---
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


2021-07-27 00:24:57

by Stephen Boyd

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Quoting Dario Binacchi (2021-07-25 09:07:25)
> 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 <[email protected]>
> Reviewed-by: Gabriel Fernandez <[email protected]>
>
> ---

Applied to clk-fixes

2021-07-28 10:06:13

by Dillon Hua

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Hi Dario,

I have a similar patch [1] submitted last year.
Unfortunately, it did not get accepted by the maintainer.

Just a reminder here for you, should remove

{ STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },

from stm32{f429, f469, f746, f769}_gates[]; or else
run into white screen after the kernel enters the console.

This patch was verified by Patrice Chotard, you can
find the history from [2].

Hope you can help to submit a patch to include [2], thanks.

[1]
https://lore.kernel.org/linux-arm-kernel/[email protected]/
https://lore.kernel.org/linux-arm-kernel/[email protected]/

resend this year:
https://lore.kernel.org/lkml/[email protected]/

[2]
https://lore.kernel.org/lkml/[email protected]/

Thanks
Best Regards

Dillon

On Mon, Jul 26, 2021 at 12:08 AM Dario Binacchi <[email protected]> wrote:
>
> 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 <[email protected]>
> Reviewed-by: Gabriel Fernandez <[email protected]>
>
> ---
> 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
>

2021-07-29 10:05:10

by Dario Binacchi

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Hi Dillon,

> Il 28/07/2021 12:03 Dillon Hua <[email protected]> ha scritto:
>
>
> Hi Dario,
>
> I have a similar patch [1] submitted last year.
> Unfortunately, it did not get accepted by the maintainer.
>
> Just a reminder here for you, should remove
>
> { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },

Thank you for your suggestion.
While testing the patch on the stm32f469-disco board I didn't
notice the white screen issue. I'll try to run the tests again.
I will let you know.

Thanks and regards,
Dario

>
> from stm32{f429, f469, f746, f769}_gates[]; or else
> run into white screen after the kernel enters the console.
>
> This patch was verified by Patrice Chotard, you can
> find the history from [2].
>
> Hope you can help to submit a patch to include [2], thanks.
>
> [1]
> https://lore.kernel.org/linux-arm-kernel/[email protected]/
> https://lore.kernel.org/linux-arm-kernel/[email protected]/
>
> resend this year:
> https://lore.kernel.org/lkml/[email protected]/
>
> [2]
> https://lore.kernel.org/lkml/[email protected]/
>
> Thanks
> Best Regards
>
> Dillon
>
> On Mon, Jul 26, 2021 at 12:08 AM Dario Binacchi <[email protected]> wrote:
> >
> > 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 <[email protected]>
> > Reviewed-by: Gabriel Fernandez <[email protected]>
> >
> > ---
> > 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
> >

2021-07-30 19:50:36

by Stephen Boyd

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Quoting Dario Binacchi (2021-07-29 03:03:22)
> Hi Dillon,
>
> > Il 28/07/2021 12:03 Dillon Hua <[email protected]> ha scritto:
> >
> >
> > Hi Dario,
> >
> > I have a similar patch [1] submitted last year.
> > Unfortunately, it did not get accepted by the maintainer.
> >
> > Just a reminder here for you, should remove
> >
> > { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
>
> Thank you for your suggestion.
> While testing the patch on the stm32f469-disco board I didn't
> notice the white screen issue. I'll try to run the tests again.
> I will let you know.
>

Ok, I'll drop this from the tree.

2021-07-30 21:25:03

by Dario Binacchi

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Hi Stephen,

> Il 30/07/2021 21:47 Stephen Boyd <[email protected]> ha scritto:
>
>
> Quoting Dario Binacchi (2021-07-29 03:03:22)
> > Hi Dillon,
> >
> > > Il 28/07/2021 12:03 Dillon Hua <[email protected]> ha scritto:
> > >
> > >
> > > Hi Dario,
> > >
> > > I have a similar patch [1] submitted last year.
> > > Unfortunately, it did not get accepted by the maintainer.
> > >
> > > Just a reminder here for you, should remove
> > >
> > > { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
> >
> > Thank you for your suggestion.
> > While testing the patch on the stm32f469-disco board I didn't
> > notice the white screen issue. I'll try to run the tests again.
> > I will let you know.
> >
>
> Ok, I'll drop this from the tree.

The patch fixes commit 517633ef630e ("clk: stm32f4: Add post divisor for I2S & SAI PLLs"),
so IMHO it should not be dropped from the tree.
What Dillon suggests, if confirmed, should be fixed by another patch.

Thanks and regards,
Dario

2021-08-01 15:02:55

by Dillon Hua

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Hi Dario

On Thu, Jul 29, 2021 at 6:03 PM Dario Binacchi <[email protected]> wrote:
>
> Hi Dillon,
>
> > Il 28/07/2021 12:03 Dillon Hua <[email protected]> ha scritto:
> >
> >
> > Hi Dario,
> >
> > I have a similar patch [1] submitted last year.
> > Unfortunately, it did not get accepted by the maintainer.
> >
> > Just a reminder here for you, should remove
> >
> > { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
>
> Thank you for your suggestion.
> While testing the patch on the stm32f469-disco board I didn't
> notice the white screen issue. I'll try to run the tests again.
> I will let you know.

Thanks, be sure clk_ignore_unused is not set from the kernel cmdline
at your test.

Best Regards
Dillon

>
> Thanks and regards,
> Dario
>
> >
> > from stm32{f429, f469, f746, f769}_gates[]; or else
> > run into white screen after the kernel enters the console.
> >
> > This patch was verified by Patrice Chotard, you can
> > find the history from [2].
> >
> > Hope you can help to submit a patch to include [2], thanks.
> >
> > [1]
> > https://lore.kernel.org/linux-arm-kernel/[email protected]/
> > https://lore.kernel.org/linux-arm-kernel/[email protected]/
> >
> > resend this year:
> > https://lore.kernel.org/lkml/[email protected]/
> >
> > [2]
> > https://lore.kernel.org/lkml/[email protected]/
> >
> > Thanks
> > Best Regards
> >
> > Dillon
> >
> > On Mon, Jul 26, 2021 at 12:08 AM Dario Binacchi <[email protected]> wrote:
> > >
> > > 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 <[email protected]>
> > > Reviewed-by: Gabriel Fernandez <[email protected]>
> > >
> > > ---
> > > 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
> > >

2021-08-01 19:41:03

by Dario Binacchi

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Hi Dillon and Stephen,

> Il 01/08/2021 16:56 Dillon Hua <[email protected]> ha scritto:
>
>
> Hi Dario
>
> On Thu, Jul 29, 2021 at 6:03 PM Dario Binacchi <[email protected]> wrote:
> >
> > Hi Dillon,
> >
> > > Il 28/07/2021 12:03 Dillon Hua <[email protected]> ha scritto:
> > >
> > >
> > > Hi Dario,
> > >
> > > I have a similar patch [1] submitted last year.
> > > Unfortunately, it did not get accepted by the maintainer.
> > >
> > > Just a reminder here for you, should remove
> > >
> > > { STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
> >
> > Thank you for your suggestion.
> > While testing the patch on the stm32f469-disco board I didn't
> > notice the white screen issue. I'll try to run the tests again.
> > I will let you know.
>
> Thanks, be sure clk_ignore_unused is not set from the kernel cmdline
> at your test.

This is the kernel command line of my tests:
console=ttySTM0,115200 root=/dev/mmcblk0p2 rw rootfstype=ext2 rootwait earlyprintk consoleblank=0 ignore_loglevel

In previous emails I forgot to mention that the patch was in turn applied to a buildroot patch [1] and
acked by Christophe Priouzeau of ST microelectronics. However, I rerun the tests and did not notice
anything strange.

I then enabled CONFIG_VT, CONFIG_FRAMEBUFFER_CONSOLE and CONFIG_LOGO, and indedd the command
'echo Dario >/dev/tty0' prints my name on the display only by removing
{STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div"}.

As said in a previous email to Stephen, the patch I submitted fixes commit 517633ef630e
("clk: stm32f4: Add post divisor for I2S & SAI PLLs"), so IMHO it should not be dropped from the tree.
What Dillon suggested should instead be fixed by another patch.

Waiting for your opinion,
Thanks and regards,
Dario

[1] https://patchwork.ozlabs.org/project/buildroot/patch/[email protected]/


>
> Best Regards
> Dillon
>
> >
> > Thanks and regards,
> > Dario
> >
> > >
> > > from stm32{f429, f469, f746, f769}_gates[]; or else
> > > run into white screen after the kernel enters the console.
> > >
> > > This patch was verified by Patrice Chotard, you can
> > > find the history from [2].
> > >
> > > Hope you can help to submit a patch to include [2], thanks.
> > >
> > > [1]
> > > https://lore.kernel.org/linux-arm-kernel/[email protected]/
> > > https://lore.kernel.org/linux-arm-kernel/[email protected]/
> > >
> > > resend this year:
> > > https://lore.kernel.org/lkml/[email protected]/
> > >
> > > [2]
> > > https://lore.kernel.org/lkml/[email protected]/
> > >
> > > Thanks
> > > Best Regards
> > >
> > > Dillon
> > >
> > > On Mon, Jul 26, 2021 at 12:08 AM Dario Binacchi <[email protected]> wrote:
> > > >
> > > > 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 <[email protected]>
> > > > Reviewed-by: Gabriel Fernandez <[email protected]>
> > > >
> > > > ---
> > > > 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
> > > >

2021-08-02 22:13:25

by Stephen Boyd

[permalink] [raw]
Subject: Re: [RESEND PATCH v4] clk: stm32f4: fix post divisor setup for I2S/SAI PLLs

Quoting Dario Binacchi (2021-08-01 12:37:10)
>
> As said in a previous email to Stephen, the patch I submitted fixes commit 517633ef630e
> ("clk: stm32f4: Add post divisor for I2S & SAI PLLs"), so IMHO it should not be dropped from the tree.
> What Dillon suggested should instead be fixed by another patch.

Ok. I'll send off the fix to Linus today.