SPI controller hangs in 2.6 and not in 2.4 (on MPC875)

[DI BACCO ANTONIO - technolabs]

Hi Melinda,

the problem in my case was caused by the following instructions to allocate the buffers for SPI controller tx and rx:

        rxbuffer = (u8*)m8xx_cpm_hostalloc(SPI_MAX_BUFFER_SIZE);  
        txbuffer = (u8*)m8xx_cpm_hostalloc(SPI_MAX_BUFFER_SIZE); 
        // Set the bd's rx and tx buffer address pointers
        rbdf->cbd_bufaddr = virt_to_bus((void *)rxbuffer);                                 
        tbdf->cbd_bufaddr = virt_to_bus((void *)txbuffer);   

I don't know why (I'm asking an opinion to Vitaly Bordug), I replaced the allocation of rx and tx buffers with:

...->cbd_bufaddr = __pa(__get_free_page(GFP_KERNEL | GFP_DMA))

but it will better to use dma_alloc_coherent.
In my case the use of m8xx_cpm_hostalloc led to an immediate kernel hang after giving the start command to the spi controller.

Bye,
Antonio.


                             
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