1 // SPDX-License-Identifier: GPL-2.0 2 /** 3 * imr_selftest.c -- Intel Isolated Memory Region self-test driver 4 * 5 * Copyright(c) 2013 Intel Corporation. 6 * Copyright(c) 2015 Bryan O'Donoghue <pure.logic@nexus-software.ie> 7 * 8 * IMR self test. The purpose of this module is to run a set of tests on the 9 * IMR API to validate it's sanity. We check for overlapping, reserved 10 * addresses and setup/teardown sanity. 11 * 12 */ 13 14 #include <asm-generic/sections.h> 15 #include <asm/cpu_device_id.h> 16 #include <asm/imr.h> 17 #include <linux/init.h> 18 #include <linux/mm.h> 19 #include <linux/types.h> 20 21 #define SELFTEST KBUILD_MODNAME ": " 22 /** 23 * imr_self_test_result - Print result string for self test. 24 * 25 * @res: result code - true if test passed false otherwise. 26 * @fmt: format string. 27 * ... variadic argument list. 28 */ 29 static __printf(2, 3) 30 void __init imr_self_test_result(int res, const char *fmt, ...) 31 { 32 va_list vlist; 33 34 /* Print pass/fail. */ 35 if (res) 36 pr_info(SELFTEST "pass "); 37 else 38 pr_info(SELFTEST "fail "); 39 40 /* Print variable string. */ 41 va_start(vlist, fmt); 42 vprintk(fmt, vlist); 43 va_end(vlist); 44 45 /* Optional warning. */ 46 WARN(res == 0, "test failed"); 47 } 48 #undef SELFTEST 49 50 /** 51 * imr_self_test 52 * 53 * Verify IMR self_test with some simple tests to verify overlap, 54 * zero sized allocations and 1 KiB sized areas. 55 * 56 */ 57 static void __init imr_self_test(void) 58 { 59 phys_addr_t base = virt_to_phys(&_text); 60 size_t size = virt_to_phys(&__end_rodata) - base; 61 const char *fmt_over = "overlapped IMR @ (0x%08lx - 0x%08lx)\n"; 62 int ret; 63 64 /* Test zero zero. */ 65 ret = imr_add_range(0, 0, 0, 0); 66 imr_self_test_result(ret < 0, "zero sized IMR\n"); 67 68 /* Test exact overlap. */ 69 ret = imr_add_range(base, size, IMR_CPU, IMR_CPU); 70 imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size)); 71 72 /* Test overlap with base inside of existing. */ 73 base += size - IMR_ALIGN; 74 ret = imr_add_range(base, size, IMR_CPU, IMR_CPU); 75 imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size)); 76 77 /* Test overlap with end inside of existing. */ 78 base -= size + IMR_ALIGN * 2; 79 ret = imr_add_range(base, size, IMR_CPU, IMR_CPU); 80 imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size)); 81 82 /* Test that a 1 KiB IMR @ zero with read/write all will bomb out. */ 83 ret = imr_add_range(0, IMR_ALIGN, IMR_READ_ACCESS_ALL, 84 IMR_WRITE_ACCESS_ALL); 85 imr_self_test_result(ret < 0, "1KiB IMR @ 0x00000000 - access-all\n"); 86 87 /* Test that a 1 KiB IMR @ zero with CPU only will work. */ 88 ret = imr_add_range(0, IMR_ALIGN, IMR_CPU, IMR_CPU); 89 imr_self_test_result(ret >= 0, "1KiB IMR @ 0x00000000 - cpu-access\n"); 90 if (ret >= 0) { 91 ret = imr_remove_range(0, IMR_ALIGN); 92 imr_self_test_result(ret == 0, "teardown - cpu-access\n"); 93 } 94 95 /* Test 2 KiB works. */ 96 size = IMR_ALIGN * 2; 97 ret = imr_add_range(0, size, IMR_READ_ACCESS_ALL, IMR_WRITE_ACCESS_ALL); 98 imr_self_test_result(ret >= 0, "2KiB IMR @ 0x00000000\n"); 99 if (ret >= 0) { 100 ret = imr_remove_range(0, size); 101 imr_self_test_result(ret == 0, "teardown 2KiB\n"); 102 } 103 } 104 105 static const struct x86_cpu_id imr_ids[] __initconst = { 106 { X86_VENDOR_INTEL, 5, 9 }, /* Intel Quark SoC X1000. */ 107 {} 108 }; 109 110 /** 111 * imr_self_test_init - entry point for IMR driver. 112 * 113 * return: -ENODEV for no IMR support 0 if good to go. 114 */ 115 static int __init imr_self_test_init(void) 116 { 117 if (x86_match_cpu(imr_ids)) 118 imr_self_test(); 119 return 0; 120 } 121 122 /** 123 * imr_self_test_exit - exit point for IMR code. 124 * 125 * return: 126 */ 127 device_initcall(imr_self_test_init); 128