diff mbox series

[V4,5/5] xen/arm: Add early printk support for SCIFA compatible UARTs

Message ID 1555513175-7596-6-git-send-email-olekstysh@gmail.com (mailing list archive)
State Superseded
Headers show
Series Renesas Stout board support (R-Car Gen2) | expand

Commit Message

Oleksandr Tyshchenko April 17, 2019, 2:59 p.m. UTC
From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>

This patch makes possible to use existing early prink code
for Renesas "Stout" board based on R-Car H2 SoC (SCIFA).

The "EARLY_PRINTK_VERSION" for that board should be 'A':
CONFIG_EARLY_PRINTK=scif,0xe6c40000,A

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
CC: Julien Grall <julien.grall@arm.com>

---
    Changes in v3:
        - It was decided not to introduce new debug-scifa.inc
          for handling SCIFA interface, but to extend existing
          debug-scif.inc for handling both interfaces.
          This patch is a result of splitting an initial patch
          "xen/arm: Add SCIFA UART support for early printk"
          and only adds a support.

    Changes in v4:
        - Drop SCIF(A) from comments
---
 xen/arch/arm/arm32/debug-scif.inc | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Julien Grall April 29, 2019, 2:30 p.m. UTC | #1
Hi Oleksandr,

On 17/04/2019 15:59, Oleksandr Tyshchenko wrote:
> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
> 
> This patch makes possible to use existing early prink code
> for Renesas "Stout" board based on R-Car H2 SoC (SCIFA).
> 
> The "EARLY_PRINTK_VERSION" for that board should be 'A':
> CONFIG_EARLY_PRINTK=scif,0xe6c40000,A
> 
> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
> CC: Julien Grall <julien.grall@arm.com>
> 
> ---
>      Changes in v3:
>          - It was decided not to introduce new debug-scifa.inc
>            for handling SCIFA interface, but to extend existing
>            debug-scif.inc for handling both interfaces.
>            This patch is a result of splitting an initial patch
>            "xen/arm: Add SCIFA UART support for early printk"
>            and only adds a support.
> 
>      Changes in v4:
>          - Drop SCIF(A) from comments
> ---
>   xen/arch/arm/arm32/debug-scif.inc | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/xen/arch/arm/arm32/debug-scif.inc b/xen/arch/arm/arm32/debug-scif.inc
> index a8d2eae..3f01c90 100644
> --- a/xen/arch/arm/arm32/debug-scif.inc
> +++ b/xen/arch/arm/arm32/debug-scif.inc
> @@ -1,7 +1,7 @@
>   /*
>    * xen/arch/arm/arm32/debug-scif.inc
>    *
> - * SCIF specific debug code
> + * SCIF(A) specific debug code
>    *
>    * Oleksandr Tyshchenko <oleksandr.tyshchenko@globallogic.com>
>    * Copyright (C) 2014, Globallogic.
> @@ -22,10 +22,13 @@
>   #ifdef EARLY_PRINTK_VERSION_NONE
>   #define STATUS_REG    SCIF_SCFSR
>   #define TX_FIFO_REG   SCIF_SCFTDR
> +#elif EARLY_PRINTK_VERSION_A
> +#define STATUS_REG    SCIFA_SCASSR
> +#define TX_FIFO_REG   SCIFA_SCAFTDR
>   #endif
>   
>   /*
> - * SCIF UART wait UART to be ready to transmit
> + * Wait UART to be ready to transmit

This change and ...

>    * rb: register which contains the UART base address
>    * rc: scratch register
>    */
> @@ -37,7 +40,7 @@
>   .endm
>   
>   /*
> - * SCIF UART transmit character
> + * UART transmit character

... this one look like more a change for the previous than this one.

>    * rb: register which contains the UART base address
>    * rt: register which contains the character to transmit
>    */
> 

Cheers,
Oleksandr Tyshchenko April 30, 2019, 11:04 a.m. UTC | #2
On 29.04.19 17:30, Julien Grall wrote:
> Hi Oleksandr,

Hi, Julien


>> @@ -22,10 +22,13 @@
>>   #ifdef EARLY_PRINTK_VERSION_NONE
>>   #define STATUS_REG    SCIF_SCFSR
>>   #define TX_FIFO_REG   SCIF_SCFTDR
>> +#elif EARLY_PRINTK_VERSION_A
>> +#define STATUS_REG    SCIFA_SCASSR
>> +#define TX_FIFO_REG   SCIFA_SCAFTDR
>>   #endif
>>     /*
>> - * SCIF UART wait UART to be ready to transmit
>> + * Wait UART to be ready to transmit
>
> This change and ...
>
>>    * rb: register which contains the UART base address
>>    * rc: scratch register
>>    */
>> @@ -37,7 +40,7 @@
>>   .endm
>>     /*
>> - * SCIF UART transmit character
>> + * UART transmit character
>
> ... this one look like more a change for the previous than this one.

agree, will move to previous patch.
diff mbox series

Patch

diff --git a/xen/arch/arm/arm32/debug-scif.inc b/xen/arch/arm/arm32/debug-scif.inc
index a8d2eae..3f01c90 100644
--- a/xen/arch/arm/arm32/debug-scif.inc
+++ b/xen/arch/arm/arm32/debug-scif.inc
@@ -1,7 +1,7 @@ 
 /*
  * xen/arch/arm/arm32/debug-scif.inc
  *
- * SCIF specific debug code
+ * SCIF(A) specific debug code
  *
  * Oleksandr Tyshchenko <oleksandr.tyshchenko@globallogic.com>
  * Copyright (C) 2014, Globallogic.
@@ -22,10 +22,13 @@ 
 #ifdef EARLY_PRINTK_VERSION_NONE
 #define STATUS_REG    SCIF_SCFSR
 #define TX_FIFO_REG   SCIF_SCFTDR
+#elif EARLY_PRINTK_VERSION_A
+#define STATUS_REG    SCIFA_SCASSR
+#define TX_FIFO_REG   SCIFA_SCAFTDR
 #endif
 
 /*
- * SCIF UART wait UART to be ready to transmit
+ * Wait UART to be ready to transmit
  * rb: register which contains the UART base address
  * rc: scratch register
  */
@@ -37,7 +40,7 @@ 
 .endm
 
 /*
- * SCIF UART transmit character
+ * UART transmit character
  * rb: register which contains the UART base address
  * rt: register which contains the character to transmit
  */