1 /* 2 * Written by Pekka Paalanen, 2008-2009 <pq@iki.fi> 3 */ 4 #include <linux/module.h> 5 #include <linux/io.h> 6 #include <linux/mmiotrace.h> 7 8 #define MODULE_NAME "testmmiotrace" 9 10 static unsigned long mmio_address; 11 module_param(mmio_address, ulong, 0); 12 MODULE_PARM_DESC(mmio_address, " Start address of the mapping of 16 kB " 13 "(or 8 MB if read_far is non-zero)."); 14 15 static unsigned long read_far = 0x400100; 16 module_param(read_far, ulong, 0); 17 MODULE_PARM_DESC(read_far, " Offset of a 32-bit read within 8 MB " 18 "(default: 0x400100)."); 19 20 static unsigned v16(unsigned i) 21 { 22 return i * 12 + 7; 23 } 24 25 static unsigned v32(unsigned i) 26 { 27 return i * 212371 + 13; 28 } 29 30 static void do_write_test(void __iomem *p) 31 { 32 unsigned int i; 33 pr_info(MODULE_NAME ": write test.\n"); 34 mmiotrace_printk("Write test.\n"); 35 36 for (i = 0; i < 256; i++) 37 iowrite8(i, p + i); 38 39 for (i = 1024; i < (5 * 1024); i += 2) 40 iowrite16(v16(i), p + i); 41 42 for (i = (5 * 1024); i < (16 * 1024); i += 4) 43 iowrite32(v32(i), p + i); 44 } 45 46 static void do_read_test(void __iomem *p) 47 { 48 unsigned int i; 49 unsigned errs[3] = { 0 }; 50 pr_info(MODULE_NAME ": read test.\n"); 51 mmiotrace_printk("Read test.\n"); 52 53 for (i = 0; i < 256; i++) 54 if (ioread8(p + i) != i) 55 ++errs[0]; 56 57 for (i = 1024; i < (5 * 1024); i += 2) 58 if (ioread16(p + i) != v16(i)) 59 ++errs[1]; 60 61 for (i = (5 * 1024); i < (16 * 1024); i += 4) 62 if (ioread32(p + i) != v32(i)) 63 ++errs[2]; 64 65 mmiotrace_printk("Read errors: 8-bit %d, 16-bit %d, 32-bit %d.\n", 66 errs[0], errs[1], errs[2]); 67 } 68 69 static void do_read_far_test(void __iomem *p) 70 { 71 pr_info(MODULE_NAME ": read far test.\n"); 72 mmiotrace_printk("Read far test.\n"); 73 74 ioread32(p + read_far); 75 } 76 77 static void do_test(unsigned long size) 78 { 79 void __iomem *p = ioremap_nocache(mmio_address, size); 80 if (!p) { 81 pr_err(MODULE_NAME ": could not ioremap, aborting.\n"); 82 return; 83 } 84 mmiotrace_printk("ioremap returned %p.\n", p); 85 do_write_test(p); 86 do_read_test(p); 87 if (read_far && read_far < size - 4) 88 do_read_far_test(p); 89 iounmap(p); 90 } 91 92 static int __init init(void) 93 { 94 unsigned long size = (read_far) ? (8 << 20) : (16 << 10); 95 96 if (mmio_address == 0) { 97 pr_err(MODULE_NAME ": you have to use the module argument " 98 "mmio_address.\n"); 99 pr_err(MODULE_NAME ": DO NOT LOAD THIS MODULE UNLESS" 100 " YOU REALLY KNOW WHAT YOU ARE DOING!\n"); 101 return -ENXIO; 102 } 103 104 pr_warning(MODULE_NAME ": WARNING: mapping %lu kB @ 0x%08lx in PCI " 105 "address space, and writing 16 kB of rubbish in there.\n", 106 size >> 10, mmio_address); 107 do_test(size); 108 pr_info(MODULE_NAME ": All done.\n"); 109 return 0; 110 } 111 112 static void __exit cleanup(void) 113 { 114 pr_debug(MODULE_NAME ": unloaded.\n"); 115 } 116 117 module_init(init); 118 module_exit(cleanup); 119 MODULE_LICENSE("GPL"); 120