78 lines
1.8 KiB
C
78 lines
1.8 KiB
C
|
/*
|
||
|
|
* Written by Pekka Paalanen, 2008 <pq@iki.fi>
|
||
|
|
*/
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <asm/io.h>
|
||
|
|
|
||
|
|
extern void __iomem *ioremap_nocache_trace(unsigned long offset,
|
||
|
|
unsigned long size);
|
||
|
|
extern void iounmap_trace(volatile void __iomem *addr);
|
||
|
|
|
||
|
|
#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;
|
||
|
|
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;
|
||
|
|
volatile unsigned int v;
|
||
|
|
for (i = 0; i < 256; i++)
|
||
|
|
v = ioread8(p + i);
|
||
|
|
for (i = 1024; i < (5 * 1024); i += 2)
|
||
|
|
v = ioread16(p + i);
|
||
|
|
for (i = (5 * 1024); i < (16 * 1024); i += 4)
|
||
|
|
v = ioread32(p + i);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void do_test(void)
|
||
|
|
{
|
||
|
|
void __iomem *p = ioremap_nocache_trace(mmio_address, 0x4000);
|
||
|
|
if (!p) {
|
||
|
|
printk(KERN_ERR MODULE_NAME ": could not ioremap IO memory, "
|
||
|
|
"aborting.\n");
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
do_write_test(p);
|
||
|
|
do_read_test(p);
|
||
|
|
iounmap_trace(p);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int __init init(void)
|
||
|
|
{
|
||
|
|
if (mmio_address == 0) {
|
||
|
|
printk(KERN_ERR MODULE_NAME ": you have to use the module "
|
||
|
|
"argument mmio_address.\n");
|
||
|
|
printk(KERN_ERR MODULE_NAME ": DO NOT LOAD THIS MODULE UNLESS"
|
||
|
|
" YOU REALLY KNOW WHAT YOU ARE DOING!\n");
|
||
|
|
return -ENXIO;
|
||
|
|
}
|
||
|
|
|
||
|
|
printk(KERN_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)
|
||
|
|
{
|
||
|
|
printk(KERN_DEBUG MODULE_NAME ": unloaded.\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
module_init(init);
|
||
|
|
module_exit(cleanup);
|
||
|
|
MODULE_LICENSE("GPL");
|