The MCI makes use of the dw_dmac driver when DMA is being used.
Due to recent changes the driver was broken because:
- the SMS field in the CTLL register received the wrong value 0
- a patch in dw_dmac (http://lkml.org/lkml/2012/1/18/52)
allowed for 64-bit transfers on the memory side, giving an illegal
value of 3 in the SRC/DST_TR_WIDTH register.
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 my patch:
[PATCH v2 2/2] dw_dmac: max_mem_width limits value for
SRC/DST_TR_WID register
Signed-off-by: Hein Tibosch <[email protected]>
---
arch/avr32/mach-at32ap/at32ap700x.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/arch/avr32/mach-at32ap/at32ap700x.c b/arch/avr32/mach-at32ap/at32ap700x.c
index 0445c4f..7250c70 100644
--- a/arch/avr32/mach-at32ap/at32ap700x.c
+++ b/arch/avr32/mach-at32ap/at32ap700x.c
@@ -1356,6 +1356,11 @@ at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
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;
if (platform_device_add_data(pdev, data,
--
1.7.8.0
Around Fri 31 Aug 2012 01:07:13 +0800 or thereabout, Hein Tibosch wrote:
> The MCI makes use of the dw_dmac driver when DMA is being used.
> Due to recent changes the driver was broken because:
> - the SMS field in the CTLL register received the wrong value 0
> - a patch in dw_dmac (http://lkml.org/lkml/2012/1/18/52)
> allowed for 64-bit transfers on the memory side, giving an illegal
> value of 3 in the SRC/DST_TR_WIDTH register.
>
> 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 my patch:
> [PATCH v2 2/2] dw_dmac: max_mem_width limits value for
> SRC/DST_TR_WID register
>
> Signed-off-by: Hein Tibosch <[email protected]>
Acked-by: Hans-Christian Egtvedt <[email protected]>
<snipp diff>
--
mvh
Hans-Christian Egtvedt