AnsweredAssumed Answered

DMA2 and SYSCFG_MEMRMP relationship

Question asked by herrera.bruno on Sep 17, 2016
Latest reply on Sep 21, 2016 by herrera.bruno
Hello,
I have a STM32F469-DISCO board with an WL1835mod SDIO on it. I'm running linux on the board with all kernel, drives and fs. It was running properly with and without DMA enabled. So I decide to remap my external SDRAM Bank 1 memory to 0x00000000 cause the RM says: In remap mode at address 0x0000 0000, the CPU can access the external memory via ICode bus instead of System bus which boosts up the performance.

So I did it by writing 0x4 on the SYSCFG_MEMRMP and also changed my linux and bootloader to run from 0x00000000. It happens that the the system runs properly and I can still use my WL1835 mod without DMA. But when DMA is enabled I start to get a DMA error(TEIF) in the first write from memory to device. My only conclusion it is caused by a BUS ERROR.

But I could not find anywhere that this configuration is not valid.
 
Here is the dump of my registers from DMA controller:

[  907.650000] dma dma1chan3: DMA_xISR:  0x00000000
[  907.650000] dma dma1chan3: SCR[0x40026458]:   0x08a15474
[  907.650000] dma dma1chan3: NDTR[0x4002645c]:  0x00001000
[  907.650000] dma dma1chan3: SPAR[0x40026460]:  0x40012c80
[  907.650000] dma dma1chan3: SM0AR[0x40026464]: 0x0076c000
[  907.650000] dma dma1chan3: SM1AR[0x40026468]: 0x0076c000
[  907.650000] dma dma1chan3: SFCR[0x4002646c]:  0x00000027
[  907.650000] dma dma1chan3: SCR[0x40026458]:   0x08a15474
[  907.650000] dma dma1chan3: NDTR[0x4002645c]:  0x0000ffff
[  907.650000] dma dma1chan3: SPAR[0x40026460]:  0x40012c80
[  907.650000] dma dma1chan3: SM0AR[0x40026464]: 0x0076c000
[  907.650000] dma dma1chan3: SM1AR[0x40026468]: 0x0076c000
[  907.650000] dma dma1chan3: SFCR[0x4002646c]:  0x00000027
[  907.650000] mmci-pl18x 40012c00.sdio: irq0 (data+cmd) 00000000
[  907.660000] dma dma1chan3: DMA_xISR:  0x02000000
[  907.660000] dma dma1chan3: SCR[0x40026458]:   0x08a15474
[  907.660000] dma dma1chan3: NDTR[0x4002645c]:  0x0000ffff
[  907.660000] dma dma1chan3: SPAR[0x40026460]:  0x40012c80
[  907.660000] dma dma1chan3: SM0AR[0x40026464]: 0x0076c000
[  907.660000] dma dma1chan3: SM1AR[0x40026468]: 0x0076c000
[  907.660000] dma dma1chan3: SFCR[0x4002646c]:  0x00000027

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