/* * Written by Pekka Paalanen, 2008 */ #include #include #include #define MODULE_NAME "testmmiotrace" static unsigned long mmio_address; module_param(mmio_address, ulong, 0); MODULE_PARM_DESC(mmio_address, "Start address of the mapping of 16 kB."); static void do_write_test(void __iomem *p) { unsigned int i; mmiotrace_printk("Write test.\n"); for (i = 0; i < 256; i++) iowrite8(i, p + i); for (i = 1024; i < (5 * 1024); i += 2) iowrite16(i * 12 + 7, p + i); for (i = (5 * 1024); i < (16 * 1024); i += 4) iowrite32(i * 212371 + 13, p + i); } static void do_read_test(void __iomem *p) { unsigned int i; mmiotrace_printk("Read test.\n"); for (i = 0; i < 256; i++) ioread8(p + i); for (i = 1024; i < (5 * 1024); i += 2) ioread16(p + i); for (i = (5 * 1024); i < (16 * 1024); i += 4) ioread32(p + i); } static void do_test(void) { void __iomem *p = ioremap_nocache(mmio_address, 0x4000); if (!p) { pr_err(MODULE_NAME ": could not ioremap, aborting.\n"); return; } mmiotrace_printk("ioremap returned %p.\n", p); do_write_test(p); do_read_test(p); iounmap(p); } static int __init init(void) { if (mmio_address == 0) { pr_err(MODULE_NAME ": you have to use the module argument " "mmio_address.\n"); pr_err(MODULE_NAME ": DO NOT LOAD THIS MODULE UNLESS" " YOU REALLY KNOW WHAT YOU ARE DOING!\n"); return -ENXIO; } pr_warning(MODULE_NAME ": WARNING: mapping 16 kB @ 0x%08lx " "in PCI address space, and writing " "rubbish in there.\n", mmio_address); do_test(); return 0; } static void __exit cleanup(void) { pr_debug(MODULE_NAME ": unloaded.\n"); } module_init(init); module_exit(cleanup); MODULE_LICENSE("GPL");