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