Markus: > > sure I am setting up the LocalBus chip select registers ok. > > I would guess this is not the case. What kind of device is this?
It is a Freescale MPC5200b: http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPC5200B You are correct. I was so concerned about the linux driver stuff ( request_region(), ioremap(), etc ), that I was locked into endless studies on that and see now I clearly overlooked some simple chip setting up. Doh! Thanks for reorienting my focus-- int init_module(void) { ... // reserve a page of memory for our hardware /proc/iomem if ( check_region(MALab_MM_START,MALab_MM_SIZE) ) { printk (KERN_ALERT "LED init_module: memory already in use\n"); return -EBUSY; } request_region(MALab_MM_START,MALab_MM_SIZE,LED_DEVICE_NAME); // enable LocalBus chip select CS2 to hit on our address range *(volatile u32 *)MPC5xxx_MM_IPBI &= ~0x00040000; *(volatile u16 *)(MPC5xxx_MM_CS2_START + 2) = MALab_MM_START >> 16; *(volatile u16 *)(MPC5xxx_MM_CS2_STOP + 2) = MALab_MM_END >> 16; *(volatile u32 *)MPC5xxx_MM_IPBI |= 0x00040000; // LocalBus Chip Select 2,3 Configuration Register *(volatile u32 *)(MPC5xxx_MBAR + 0x0308) = 0x03031110; *(volatile u32 *)(MPC5xxx_MBAR + 0x030c) = 0x03031110; // LocalBus Chip Select Control Register *(volatile u32 *)(MPC5xxx_MBAR + 0x0318) |= 0x01000000; // map our physical address into kernal virtual address space ioaddr = ioremap(MALab_MM_START,MALab_MM_SIZE); printk(KERN_ALERT "ioaddr: 0x%08x\n", (u32)ioaddr); and later, any of these calls work: _______________________________________________ Linuxppc-embedded mailing list [email protected] https://ozlabs.org/mailman/listinfo/linuxppc-embedded
