Hello, I am having an important trouble while communicating with my PCI Endpoint devices MMIO. I am using T1042D4RDB-64B. PowerPC e5500 processor with kernel version 4.19 and default PCI driver is 'pcieport'. Kernel is built with Yocto 2.7.
I have a FPGA memory controller card which is programmed to light GPIO leds when it's memory is filled with data on PCI. I wrote a driver and tested it with x86 based Ubuntu and it's working as expected. I used same driver with T1042D4RDB-64B. Kernel is giving UNRECOVERABLE MACHINE CHECK error when I try to read the same area I wrote before. Leds are also not lighting so that this means write operation is not working too. Seems like ATMU is not transferring the transactions to PCI endpoint device. I tried same code piece with another endpoint device ( This is a GPU ) and I had same problem again. I am seeking some help about this issue. *Detailed thread is here:* https://community.nxp.com/thread/522267 *Driver code piece* pci_request_regions(dev, "IO-pci"); pci_enable_device_mem(dev); printk(KERN_INFO "Physical address start: %lX",pci_resource_start(dev,BAR_IO)); printk(KERN_INFO "Physical address end: %lX",pci_resource_end(dev,BAR_IO)); iomapped_addr_start = ioremap(pci_resfreescaleource_start(dev,BAR_IO),pci_resource_len(dev,BAR_IO)); printk(KERN_INFO "Virtual address start: %lX",iomapped_addr_start); if(iomapped_addr_start != NULL || iomapped_addr_start != 0) { for(i=0;i<pci_resource_len(dev,BAR_IO);i++) { printk(KERN_INFO "Before Write %lX \n",iomapped_addr_start+i); writeb(5,iomapped_addr_start+i); printk(KERN_INFO "Writed 5 \n"); printk(KERN_INFO "Readed %d",readb(iomapped_addr_start+i)); } } *Output:* Physical address start: 0x21000000 Physical address end: 0x210007ff Virtual address start: 80000800888C0000 Before Write 80000800888C0000 Writed 5 ntDlaibslaibnlgi nlgo clko cdke bduegbguginggi ngdu de ueto t ko erkenernl eltat x 80000001 cecar 0x020c0000 cecar2 0x00001010 CaCuasuesde db yb y( f(rformom M MCSCSR=R=a0a00000):): L Looad Error Report KeKrenrenle lp apannici c -- n onott s ysynncicningg: Unrecoverable Machine chek
