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 <asm/io.h> 18 19 #include <linux/init.h> 20 #include <linux/mm.h> 21 #include <linux/types.h> 22 23 #define SELFTEST KBUILD_MODNAME ": " 24 /** 25 * imr_self_test_result - Print result string for self test. 26 * 27 * @res: result code - true if test passed false otherwise. 28 * @fmt: format string. 29 * ... variadic argument list. 30 */ 31 static __printf(2, 3) 32 void __init imr_self_test_result(int res, const char *fmt, ...) 33 { 34 va_list vlist; 35 36 /* Print pass/fail. */ 37 if (res) 38 pr_info(SELFTEST "pass "); 39 else 40 pr_info(SELFTEST "fail "); 41 42 /* Print variable string. */ 43 va_start(vlist, fmt); 44 vprintk(fmt, vlist); 45 va_end(vlist); 46 47 /* Optional warning. */ 48 WARN(res == 0, "test failed"); 49 } 50 #undef SELFTEST 51 52 /** 53 * imr_self_test 54 * 55 * Verify IMR self_test with some simple tests to verify overlap, 56 * zero sized allocations and 1 KiB sized areas. 57 * 58 */ 59 static void __init imr_self_test(void) 60 { 61 phys_addr_t base = virt_to_phys(&_text); 62 size_t size = virt_to_phys(&__end_rodata) - base; 63 const char *fmt_over = "overlapped IMR @ (0x%08lx - 0x%08lx)\n"; 64 int ret; 65 66 /* Test zero zero. */ 67 ret = imr_add_range(0, 0, 0, 0); 68 imr_self_test_result(ret < 0, "zero sized IMR\n"); 69 70 /* Test exact overlap. */ 71 ret = imr_add_range(base, size, IMR_CPU, IMR_CPU); 72 imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size)); 73 74 /* Test overlap with base inside of existing. */ 75 base += size - IMR_ALIGN; 76 ret = imr_add_range(base, size, IMR_CPU, IMR_CPU); 77 imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size)); 78 79 /* Test overlap with end inside of existing. */ 80 base -= size + IMR_ALIGN * 2; 81 ret = imr_add_range(base, size, IMR_CPU, IMR_CPU); 82 imr_self_test_result(ret < 0, fmt_over, __va(base), __va(base + size)); 83 84 /* Test that a 1 KiB IMR @ zero with read/write all will bomb out. */ 85 ret = imr_add_range(0, IMR_ALIGN, IMR_READ_ACCESS_ALL, 86 IMR_WRITE_ACCESS_ALL); 87 imr_self_test_result(ret < 0, "1KiB IMR @ 0x00000000 - access-all\n"); 88 89 /* Test that a 1 KiB IMR @ zero with CPU only will work. */ 90 ret = imr_add_range(0, IMR_ALIGN, IMR_CPU, IMR_CPU); 91 imr_self_test_result(ret >= 0, "1KiB IMR @ 0x00000000 - cpu-access\n"); 92 if (ret >= 0) { 93 ret = imr_remove_range(0, IMR_ALIGN); 94 imr_self_test_result(ret == 0, "teardown - cpu-access\n"); 95 } 96 97 /* Test 2 KiB works. */ 98 size = IMR_ALIGN * 2; 99 ret = imr_add_range(0, size, IMR_READ_ACCESS_ALL, IMR_WRITE_ACCESS_ALL); 100 imr_self_test_result(ret >= 0, "2KiB IMR @ 0x00000000\n"); 101 if (ret >= 0) { 102 ret = imr_remove_range(0, size); 103 imr_self_test_result(ret == 0, "teardown 2KiB\n"); 104 } 105 } 106 107 static const struct x86_cpu_id imr_ids[] __initconst = { 108 X86_MATCH_VENDOR_FAM_MODEL(INTEL, 5, INTEL_FAM5_QUARK_X1000, NULL), 109 {} 110 }; 111 112 /** 113 * imr_self_test_init - entry point for IMR driver. 114 * 115 * return: -ENODEV for no IMR support 0 if good to go. 116 */ 117 static int __init imr_self_test_init(void) 118 { 119 if (x86_match_cpu(imr_ids)) 120 imr_self_test(); 121 return 0; 122 } 123 124 /** 125 * imr_self_test_exit - exit point for IMR code. 126 * 127 * return: 128 */ 129 device_initcall(imr_self_test_init); 130