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-   -   how to use PCI shared memory ? (https://www.linuxquestions.org/questions/linux-kernel-70/how-to-use-pci-shared-memory-520522/)

srinivasbakki 01-18-2007 09:54 AM

how to use PCI shared memory ?
 
Hi,
I have a i386 host machine. on the PCI bus i have a device which needs to access a shared memory on another PCI device. This shared memory is shared between device and the host processor. Iam using linux kernel 2.6.14. I use the shared memory this way :

ioremap the shared memory and then i give the physical address of this shared memory to the PCI device which wants to access it. i get this physical address from lspci output. i get this error " Uhhuh. NMI received Dazed and confused u probably have bad RAM chips..."

Here do i need to make virt_to_bus of the address i got from the ioremap ?
But its generally taken that on the i386 machine both the bus address and physical address are the same.

But still if i do virt_to_bus on the ioremaped address i see that the bus address and the physical address are not the same.

Any help ???


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