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 void __init imr_self_test_result(int res, const char *fmt, ...)
 29{
 30	va_list vlist;
 31
 32	/* Print pass/fail. */
 33	if (res)
 34		pr_info(SELFTEST "pass ");
 35	else
 36		pr_info(SELFTEST "fail ");
 37
 38	/* Print variable string. */
 39	va_start(vlist, fmt);
 40	vprintk(fmt, vlist);
 41	va_end(vlist);
 42
 43	/* Optional warning. */
 44	WARN(res == 0, "test failed");
 45}
 46#undef SELFTEST
 47
 48/**
 49 * imr_self_test
 50 *
 51 * Verify IMR self_test with some simple tests to verify overlap,
 52 * zero sized allocations and 1 KiB sized areas.
 53 *
 54 */
 55static void __init imr_self_test(void)
 56{
 57	phys_addr_t base  = virt_to_phys(&_text);
 58	size_t size = virt_to_phys(&__end_rodata) - base;
 59	const char *fmt_over = "overlapped IMR @ (0x%08lx - 0x%08lx)\n";
 60	int ret;
 61
 62	/* Test zero zero. */
 63	ret = imr_add_range(0, 0, 0, 0);
 64	imr_self_test_result(ret < 0, "zero sized IMR\n");
 65
 66	/* Test exact overlap. */
 67	ret = imr_add_range(base, size, IMR_CPU, IMR_CPU);
 68	imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size));
 69
 70	/* Test overlap with base inside of existing. */
 71	base += size - IMR_ALIGN;
 72	ret = imr_add_range(base, size, IMR_CPU, IMR_CPU);
 73	imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size));
 74
 75	/* Test overlap with end inside of existing. */
 76	base -= size + IMR_ALIGN * 2;
 77	ret = imr_add_range(base, size, IMR_CPU, IMR_CPU);
 78	imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size));
 79
 80	/* Test that a 1 KiB IMR @ zero with read/write all will bomb out. */
 81	ret = imr_add_range(0, IMR_ALIGN, IMR_READ_ACCESS_ALL,
 82			    IMR_WRITE_ACCESS_ALL);
 83	imr_self_test_result(ret < 0, "1KiB IMR @ 0x00000000 - access-all\n");
 84
 85	/* Test that a 1 KiB IMR @ zero with CPU only will work. */
 86	ret = imr_add_range(0, IMR_ALIGN, IMR_CPU, IMR_CPU);
 87	imr_self_test_result(ret >= 0, "1KiB IMR @ 0x00000000 - cpu-access\n");
 88	if (ret >= 0) {
 89		ret = imr_remove_range(0, IMR_ALIGN);
 90		imr_self_test_result(ret == 0, "teardown - cpu-access\n");
 91	}
 92
 93	/* Test 2 KiB works. */
 94	size = IMR_ALIGN * 2;
 95	ret = imr_add_range(0, size, IMR_READ_ACCESS_ALL, IMR_WRITE_ACCESS_ALL);
 96	imr_self_test_result(ret >= 0, "2KiB IMR @ 0x00000000\n");
 97	if (ret >= 0) {
 98		ret = imr_remove_range(0, size);
 99		imr_self_test_result(ret == 0, "teardown 2KiB\n");
100	}
101}
102
103static const struct x86_cpu_id imr_ids[] __initconst = {
104	{ X86_VENDOR_INTEL, 5, 9 },	/* Intel Quark SoC X1000. */
105	{}
106};
107
108/**
109 * imr_self_test_init - entry point for IMR driver.
110 *
111 * return: -ENODEV for no IMR support 0 if good to go.
112 */
113static int __init imr_self_test_init(void)
114{
115	if (x86_match_cpu(imr_ids))
116		imr_self_test();
117	return 0;
118}
119
120/**
121 * imr_self_test_exit - exit point for IMR code.
122 *
123 * return:
124 */
125device_initcall(imr_self_test_init);