diff mbox series

arm: socfpga: execute cold reboot by default

Message ID 20190503091507.6159-1-simon.k.r.goldschmidt@gmail.com (mailing list archive)
State Mainlined
Commit 716864586c6261b079a4d5ebc02f19adc8e6aa38
Headers show
Series arm: socfpga: execute cold reboot by default | expand

Commit Message

Simon Goldschmidt May 3, 2019, 9:15 a.m. UTC
This changes system reboot for socfpga to issue a cold reboot by
default instead of a warm reboot.

Warm reboot can still be used by setting reboot_mode to
REBOOT_WARM (e.g. via kernel command line 'reboot='), but this
patch ensures cold reboot is issued for both REBOOT_COLD and
REBOOT_HARD.

Also, cold reboot is more fail safe than warm reboot has some
issues at least fo CSEL=0 and BSEL=qspi, where the boot rom does
not set the qspi clock to a valid range.

Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
---

See discussion in this thread on the u-boot ML:
https://lists.denx.de/pipermail/u-boot/2019-April/367463.html
---
 arch/arm/mach-socfpga/socfpga.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

Comments

Dinh Nguyen May 8, 2019, 1:37 a.m. UTC | #1
On 5/3/19 4:15 AM, Simon Goldschmidt wrote:
> This changes system reboot for socfpga to issue a cold reboot by
> default instead of a warm reboot.
> 
> Warm reboot can still be used by setting reboot_mode to
> REBOOT_WARM (e.g. via kernel command line 'reboot='), but this
> patch ensures cold reboot is issued for both REBOOT_COLD and
> REBOOT_HARD.
> 
> Also, cold reboot is more fail safe than warm reboot has some
> issues at least fo CSEL=0 and BSEL=qspi, where the boot rom does
> not set the qspi clock to a valid range.
> 
> Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
> ---
> 
> See discussion in this thread on the u-boot ML:
> https://lists.denx.de/pipermail/u-boot/2019-April/367463.html
> ---
>  arch/arm/mach-socfpga/socfpga.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c
> index 816da0eb6..6abfbf140 100644
> --- a/arch/arm/mach-socfpga/socfpga.c
> +++ b/arch/arm/mach-socfpga/socfpga.c
> @@ -85,10 +85,10 @@ static void socfpga_cyclone5_restart(enum reboot_mode mode, const char *cmd)
>  
>  	temp = readl(rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL);
>  
> -	if (mode == REBOOT_HARD)
> -		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
> -	else
> +	if (mode == REBOOT_WARM)
>  		temp |= RSTMGR_CTRL_SWWARMRSTREQ;
> +	else
> +		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
>  	writel(temp, rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL);
>  }
>  
> @@ -98,10 +98,10 @@ static void socfpga_arria10_restart(enum reboot_mode mode, const char *cmd)
>  
>  	temp = readl(rst_manager_base_addr + SOCFPGA_A10_RSTMGR_CTRL);
>  
> -	if (mode == REBOOT_HARD)
> -		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
> -	else
> +	if (mode == REBOOT_WARM)
>  		temp |= RSTMGR_CTRL_SWWARMRSTREQ;
> +	else
> +		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
>  	writel(temp, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_CTRL);
>  }
>  
> 

Applied, thanks! I think this patch needs to get back-ported into stable
kernel version as well, right?

Dinh
Simon Goldschmidt May 8, 2019, 8:07 p.m. UTC | #2
Am 08.05.2019 um 03:37 schrieb Dinh Nguyen:
> 
> 
> On 5/3/19 4:15 AM, Simon Goldschmidt wrote:
>> This changes system reboot for socfpga to issue a cold reboot by
>> default instead of a warm reboot.
>>
>> Warm reboot can still be used by setting reboot_mode to
>> REBOOT_WARM (e.g. via kernel command line 'reboot='), but this
>> patch ensures cold reboot is issued for both REBOOT_COLD and
>> REBOOT_HARD.
>>
>> Also, cold reboot is more fail safe than warm reboot has some
>> issues at least fo CSEL=0 and BSEL=qspi, where the boot rom does
>> not set the qspi clock to a valid range.
>>
>> Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
>> ---
>>
>> See discussion in this thread on the u-boot ML:
>> https://lists.denx.de/pipermail/u-boot/2019-April/367463.html
>> ---
>>   arch/arm/mach-socfpga/socfpga.c | 12 ++++++------
>>   1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c
>> index 816da0eb6..6abfbf140 100644
>> --- a/arch/arm/mach-socfpga/socfpga.c
>> +++ b/arch/arm/mach-socfpga/socfpga.c
>> @@ -85,10 +85,10 @@ static void socfpga_cyclone5_restart(enum reboot_mode mode, const char *cmd)
>>   
>>   	temp = readl(rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL);
>>   
>> -	if (mode == REBOOT_HARD)
>> -		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
>> -	else
>> +	if (mode == REBOOT_WARM)
>>   		temp |= RSTMGR_CTRL_SWWARMRSTREQ;
>> +	else
>> +		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
>>   	writel(temp, rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL);
>>   }
>>   
>> @@ -98,10 +98,10 @@ static void socfpga_arria10_restart(enum reboot_mode mode, const char *cmd)
>>   
>>   	temp = readl(rst_manager_base_addr + SOCFPGA_A10_RSTMGR_CTRL);
>>   
>> -	if (mode == REBOOT_HARD)
>> -		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
>> -	else
>> +	if (mode == REBOOT_WARM)
>>   		temp |= RSTMGR_CTRL_SWWARMRSTREQ;
>> +	else
>> +		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
>>   	writel(temp, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_CTRL);
>>   }
>>   
>>
> 
> Applied, thanks! I think this patch needs to get back-ported into stable
> kernel version as well, right?

Well, it's certainly wrong as it was.

But as I saw myself, switching from warm to cold reset might have some 
implications that would at least in some configurations require changes 
to existing configurations to keep the board booting.

So while this certainly fixes a bug (warm reboot is executed instead of 
cold reboot like standard/requested), I don't know what's the standard 
procedure for a backport regarding fix vs. breaking boards.

Regards,
Simon
diff mbox series

Patch

diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c
index 816da0eb6..6abfbf140 100644
--- a/arch/arm/mach-socfpga/socfpga.c
+++ b/arch/arm/mach-socfpga/socfpga.c
@@ -85,10 +85,10 @@  static void socfpga_cyclone5_restart(enum reboot_mode mode, const char *cmd)
 
 	temp = readl(rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL);
 
-	if (mode == REBOOT_HARD)
-		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
-	else
+	if (mode == REBOOT_WARM)
 		temp |= RSTMGR_CTRL_SWWARMRSTREQ;
+	else
+		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
 	writel(temp, rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL);
 }
 
@@ -98,10 +98,10 @@  static void socfpga_arria10_restart(enum reboot_mode mode, const char *cmd)
 
 	temp = readl(rst_manager_base_addr + SOCFPGA_A10_RSTMGR_CTRL);
 
-	if (mode == REBOOT_HARD)
-		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
-	else
+	if (mode == REBOOT_WARM)
 		temp |= RSTMGR_CTRL_SWWARMRSTREQ;
+	else
+		temp |= RSTMGR_CTRL_SWCOLDRSTREQ;
 	writel(temp, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_CTRL);
 }