[PATCH] bsp/atsam: Fix XDMAD status

[Christian Mauderer]

I would like to apply this patch to master (ticket #4173) and to the 5 
branch (ticket #4172). It would be great if someone could have a look 
and acknowledge it.

On 09/11/2020 09:16, Christian Mauderer wrote:
> In "bsp/atsam: Simplify XDMAD_Handler()" (5f813694f68cee) the interrupt
> callback has been made unconditional. That allowed to avoid some special
> deadlock situations in error cases. But it removed part of the XDMAD
> status handling.
> 
> This patch adds the ability to update the XDMAD status from the
> callback if that is necessary for the driver.
> 
> Fixes #4172
> ---
>   .../contrib/libraries/libchip/source/xdmad.c  | 60 ++++++++++++++++++-
>   .../arm/atsam/include/libchip/include/xdmad.h |  4 ++
>   2 files changed, 63 insertions(+), 1 deletion(-)
> 
> diff --git a/bsps/arm/atsam/contrib/libraries/libchip/source/xdmad.c b/bsps/arm/atsam/contrib/libraries/libchip/source/xdmad.c
> index 13b227036e..161cf0bee4 100644
> --- a/bsps/arm/atsam/contrib/libraries/libchip/source/xdmad.c
> +++ b/bsps/arm/atsam/contrib/libraries/libchip/source/xdmad.c
> @@ -132,9 +132,66 @@ static uint32_t XDMAD_AllocateXdmacChannel(sXdmad *pXdmad,
>   	return XDMAD_ALLOC_FAILED;
>   }
>   
> +/*
> + * Update the internal xdmad state. Returns true if further processing in the
> + * callback is recommended.
> + *
> + * In an earlier version of the API this has been done by the interrupt handler
> + * directly. But in some cases the application might want to process some of the
> + * other interrupts too. Therefore the user callback should now decide itself
> + * whether this is necessary or not.
> + */
> +bool XDMAD_UpdateStatusFromCallback(sXdmad *pXdmad,
> +		uint32_t Channel,
> +		uint32_t status)
> +{
> +	Xdmac *pXdmac;
> +	uint32_t xdmaGlobalChStatus;
> +	bool bExec;
> +
> +	bExec = false;
> +	pXdmac = pXdmad->pXdmacs;
> +	xdmaGlobalChStatus = XDMAC_GetGlobalChStatus(pXdmac);
> +
> +	if ((xdmaGlobalChStatus & (XDMAC_GS_ST0 << Channel)) == 0) {
> +		uint32_t xdmaChannelIntMask;
> +		sXdmadChannel *pCh;
> +
> +		pCh = &pXdmad->XdmaChannels[Channel];
> +
> +		xdmaChannelIntMask = XDMAC_GetChannelItMask(pXdmac, Channel);
> +		status &= xdmaChannelIntMask;
> +
> +		if (status & XDMAC_CIS_BIS) {
> +			if ((xdmaChannelIntMask & XDMAC_CIM_LIM) == 0) {
> +				pCh->state = XDMAD_STATE_DONE;
> +				bExec = true;
> +			}
> +		}
> +
> +		if (status & XDMAC_CIS_LIS) {
> +			pCh->state = XDMAD_STATE_DONE;
> +			bExec = true;
> +		}
> +
> +		if (status & XDMAC_CIS_DIS) {
> +			pCh->state = XDMAD_STATE_DONE;
> +			bExec = true;
> +		}
> +	} else {
> +		/* Block end interrupt for LLI dma mode */
> +		if (XDMAC_GetChannelIsr(pXdmac, Channel) & XDMAC_CIS_BIS) {
> +			bExec = true;
> +		}
> +	}
> +
> +	return bExec;
> +}
> +
>   void XDMAD_DoNothingCallback(uint32_t Channel, void *pArg, uint32_t status)
>   {
> -	/* Do nothing */
> +	/* Do nothing except status update */
> +	XDMAD_UpdateStatusFromCallback((sXdmad *)pArg, Channel, status);
>   }
>   
>   /*----------------------------------------------------------------------------
> @@ -157,6 +214,7 @@ static void XDMAD_SysInitialize(void)
>   
>   	for (j = 0; j < pXdmad->numChannels; j ++) {
>   		pXdmad->XdmaChannels[j].fCallback = XDMAD_DoNothingCallback;
> +		pXdmad->XdmaChannels[j].pArg = (void *)pXdmad;
>   	}
>   
>   	sc = rtems_interrupt_handler_install(
> diff --git a/bsps/arm/atsam/include/libchip/include/xdmad.h b/bsps/arm/atsam/include/libchip/include/xdmad.h
> index 97e24c880b..cba3d052ab 100644
> --- a/bsps/arm/atsam/include/libchip/include/xdmad.h
> +++ b/bsps/arm/atsam/include/libchip/include/xdmad.h
> @@ -241,6 +241,10 @@ extern eXdmadRC XDMAD_StartTransfer(sXdmad *pXdmad, uint32_t dwChannel);
>   
>   extern void XDMAD_DoNothingCallback(uint32_t Channel, void *pArg, uint32_t status);
>   
> +extern bool XDMAD_UpdateStatusFromCallback(sXdmad *pXdmad,
> +		uint32_t Channel,
> +		uint32_t status);
> +
>   extern eXdmadRC XDMAD_SetCallback(sXdmad *pXdmad,
>   								   uint32_t dwChannel,
>   								   XdmadTransferCallback fCallback,
> 

-- 
--------------------------------------------
embedded brains GmbH
Christian MAUDERER
Dornierstr. 4
82178 Puchheim
Germany
email: christian.mauderer at embedded-brains.de
Phone: +49-89-18 94 741 - 18
Fax:   +49-89-18 94 741 - 08
PGP: Public key available on request.

embedded brains GmbH
Registergericht: Amtsgericht München
Registernummer: HRB 157899
Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler
Unsere Datenschutzerklärung finden Sie hier:
https://embedded-brains.de/datenschutzerklaerung/