1/**
  2 * imr_selftest.c -- Intel Isolated Memory Region self-test driver
  3 *
  4 * Copyright(c) 2013 Intel Corporation.
  5 * Copyright(c) 2015 Bryan O'Donoghue <pure.logic@nexus-software.ie>
  6 *
  7 * IMR self test. The purpose of this module is to run a set of tests on the
  8 * IMR API to validate it's sanity. We check for overlapping, reserved
  9 * addresses and setup/teardown sanity.
 10 *
 11 */
 12
 13#include <asm-generic/sections.h>
 14#include <asm/cpu_device_id.h>
 15#include <asm/imr.h>
 16#include <linux/init.h>
 17#include <linux/mm.h>
 18#include <linux/types.h>
 19
 20#define SELFTEST KBUILD_MODNAME ": "
 21/**
 22 * imr_self_test_result - Print result string for self test.
 23 *
 24 * @res:	result code - true if test passed false otherwise.
 25 * @fmt:	format string.
 26 * ...		variadic argument list.
 27 */
 28static __printf(2, 3)
 29void __init imr_self_test_result(int res, const char *fmt, ...)
 30{
 31	va_list vlist;
 32
 33	/* Print pass/fail. */
 34	if (res)
 35		pr_info(SELFTEST "pass ");
 36	else
 37		pr_info(SELFTEST "fail ");
 38
 39	/* Print variable string. */
 40	va_start(vlist, fmt);
 41	vprintk(fmt, vlist);
 42	va_end(vlist);
 43
 44	/* Optional warning. */
 45	WARN(res == 0, "test failed");
 46}
 47#undef SELFTEST
 48
 49/**
 50 * imr_self_test
 51 *
 52 * Verify IMR self_test with some simple tests to verify overlap,
 53 * zero sized allocations and 1 KiB sized areas.
 54 *
 55 */
 56static void __init imr_self_test(void)
 57{
 58	phys_addr_t base  = virt_to_phys(&_text);
 59	size_t size = virt_to_phys(&__end_rodata) - base;
 60	const char *fmt_over = "overlapped IMR @ (0x%08lx - 0x%08lx)\n";
 61	int ret;
 62
 63	/* Test zero zero. */
 64	ret = imr_add_range(0, 0, 0, 0);
 65	imr_self_test_result(ret < 0, "zero sized IMR\n");
 66
 67	/* Test exact overlap. */
 68	ret = imr_add_range(base, size, IMR_CPU, IMR_CPU);
 69	imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size));
 70
 71	/* Test overlap with base inside of existing. */
 72	base += size - IMR_ALIGN;
 73	ret = imr_add_range(base, size, IMR_CPU, IMR_CPU);
 74	imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size));
 75
 76	/* Test overlap with end inside of existing. */
 77	base -= size + IMR_ALIGN * 2;
 78	ret = imr_add_range(base, size, IMR_CPU, IMR_CPU);
 79	imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size));
 80
 81	/* Test that a 1 KiB IMR @ zero with read/write all will bomb out. */
 82	ret = imr_add_range(0, IMR_ALIGN, IMR_READ_ACCESS_ALL,
 83			    IMR_WRITE_ACCESS_ALL);
 84	imr_self_test_result(ret < 0, "1KiB IMR @ 0x00000000 - access-all\n");
 85
 86	/* Test that a 1 KiB IMR @ zero with CPU only will work. */
 87	ret = imr_add_range(0, IMR_ALIGN, IMR_CPU, IMR_CPU);
 88	imr_self_test_result(ret >= 0, "1KiB IMR @ 0x00000000 - cpu-access\n");
 89	if (ret >= 0) {
 90		ret = imr_remove_range(0, IMR_ALIGN);
 91		imr_self_test_result(ret == 0, "teardown - cpu-access\n");
 92	}
 93
 94	/* Test 2 KiB works. */
 95	size = IMR_ALIGN * 2;
 96	ret = imr_add_range(0, size, IMR_READ_ACCESS_ALL, IMR_WRITE_ACCESS_ALL);
 97	imr_self_test_result(ret >= 0, "2KiB IMR @ 0x00000000\n");
 98	if (ret >= 0) {
 99		ret = imr_remove_range(0, size);
100		imr_self_test_result(ret == 0, "teardown 2KiB\n");
101	}
102}
103
104static const struct x86_cpu_id imr_ids[] __initconst = {
105	{ X86_VENDOR_INTEL, 5, 9 },	/* Intel Quark SoC X1000. */
106	{}
107};
108
109/**
110 * imr_self_test_init - entry point for IMR driver.
111 *
112 * return: -ENODEV for no IMR support 0 if good to go.
113 */
114static int __init imr_self_test_init(void)
115{
116	if (x86_match_cpu(imr_ids))
117		imr_self_test();
118	return 0;
119}
120
121/**
122 * imr_self_test_exit - exit point for IMR code.
123 *
124 * return:
125 */
126device_initcall(imr_self_test_init);