[PATCH v4 3/3] avr32: at32ap700x: set DMA slave properties for MCI dw_dmac

[PATCH v4 3/3] avr32: at32ap700x: set DMA slave properties for MCI dw_dmac

[Hein Tibosch]

From: Hein Tibosch <hein_tibosch@yahoo.es>

v4: now based and tested on 3.6-rc4

The MCI makes use of the dw_dmac driver when DMA is being used.
Due to recent changes to dw_dmac the MCI+DMA driver was broken because:
- a patch in dw_dmac allowed for 64-bit transfers on the memory side, giving
an illegal value of 3 in the SRC/DST_TR_WIDTH register
(http://lkml.org/lkml/2012/1/18/52)
- the SMS field in the CTLL register received the wrong value 0

This patch sets the SMS (Source Master Select) to 1 and limits
the maximum transfer width to 32 bits.

Note: this can only be applied after the previous:
[PATCH v3 2/3] dw_dmac: max_mem_width limits value for SRC/DST_TR_WID register

Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
---
 arch/avr32/mach-at32ap/at32ap700x.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/avr32/mach-at32ap/at32ap700x.c b/arch/avr32/mach-at32ap/at32ap700x.c
index 0445c4f..33c56e7 100644
--- a/arch/avr32/mach-at32ap/at32ap700x.c
+++ b/arch/avr32/mach-at32ap/at32ap700x.c
@@ -1355,6 +1355,10 @@ at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
 				| DWC_CFGH_DST_PER(1));
 	slave->sdata.cfg_lo &= ~(DWC_CFGL_HS_DST_POL
 				| DWC_CFGL_HS_SRC_POL);
+	/* Setup DMA controller: let source be master */
+	slave->sdata.src_master = 1;
+	/* Limit maximum transfer width to 32-bit */
+	slave->sdata.max_mem_width = DW_MEM_WIDTH_32;

 	data->dma_slave = slave;

-- 
1.7.8.0

Re: [PATCH v4 3/3] avr32: at32ap700x: set DMA slave properties for MCI dw_dmac

[Andy Shevchenko]

On Sun, Sep 2, 2012 at 8:54 PM, Hein Tibosch <hein_tibosch@yahoo.es> wrote:
> --- a/arch/avr32/mach-at32ap/at32ap700x.c
> +++ b/arch/avr32/mach-at32ap/at32ap700x.c
> @@ -1355,6 +1355,10 @@ at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
>                                 | DWC_CFGH_DST_PER(1));
>         slave->sdata.cfg_lo &= ~(DWC_CFGL_HS_DST_POL
>                                 | DWC_CFGL_HS_SRC_POL);
> +       /* Setup DMA controller: let source be master */
> +       slave->sdata.src_master = 1;
I don't know the details, but do you want to set up dst_master as well?

> +       /* Limit maximum transfer width to 32-bit */
> +       slave->sdata.max_mem_width = DW_MEM_WIDTH_32;
It's under question regarding to my comments on previous patch.

-- 
With Best Regards,
Andy Shevchenko