[app][tests] add new memory test

-Use the VMM to allocate a large chunk of uncached physical memory
-if no VMM, allocate from heap
-Do a simple own address test then a pattern and moving inversion test

app/tests/cache_tests.c

@@ -72,7 +72,7 @@ static int cache_tests(int argc, const cmd_args *argv)
 }
 
 STATIC_COMMAND_START
-STATIC_COMMAND("cache_tests", "tests of cpu cache", &cache_tests)
+STATIC_COMMAND("cache_tests", "test/bench the cpu cache", &cache_tests)
 STATIC_COMMAND_END(cache_tests);
 
 #endif

app/tests/mem_tests.c

@@ -0,0 +1,231 @@
+/*
+ * Copyright (c) 2014 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <err.h>
+#include <arch.h>
+#include <arch/ops.h>
+#include <lib/console.h>
+#include <platform.h>
+
+#if WITH_KERNEL_VM
+#include <kernel/vm.h>
+#endif
+
+static void mem_test_fail(void *ptr, uint32_t should, uint32_t is)
+{
+    printf("ERROR at %p: should be 0x%x, is 0x%x\n", ptr, should, is);
+
+    ptr = (void *)ROUNDDOWN((uintptr_t)ptr, 64);
+    hexdump(ptr, 128);
+}
+
+static status_t do_pattern_test(void *ptr, size_t len, uint32_t pat)
+{
+    volatile uint32_t *vbuf32 = ptr;
+    size_t i;
+
+    printf("\tpattern 0x%08x\n", pat);
+    for (i = 0; i < len / 4; i++) {
+        vbuf32[i] = pat;
+    }
+
+    for (i = 0; i < len / 4; i++) {
+        if (vbuf32[i] != pat) {
+            mem_test_fail((void *)&vbuf32[i], pat, vbuf32[i]);
+            return ERR_GENERIC;
+        }
+    }
+
+    return NO_ERROR;
+}
+
+static status_t do_moving_inversion_test(void *ptr, size_t len, uint32_t pat)
+{
+    volatile uint32_t *vbuf32 = ptr;
+    size_t i;
+
+    printf("\tpattern 0x%08x\n", pat);
+
+    /* fill memory */
+    for (i = 0; i < len / 4; i++) {
+        vbuf32[i] = pat;
+    }
+
+    /* from the bottom, walk through each cell, inverting the value */
+    //printf("\t\tbottom up invert\n");
+    for (i = 0; i < len / 4; i++) {
+        if (vbuf32[i] != pat) {
+            mem_test_fail((void *)&vbuf32[i], pat, vbuf32[i]);
+            return ERR_GENERIC;
+        }
+
+        vbuf32[i] = ~pat;
+    }
+
+    /* repeat, walking from top down */
+    //printf("\t\ttop down invert\n");
+    for (i = len / 4; i > 0; i--) {
+        if (vbuf32[i-1] != ~pat) {
+            mem_test_fail((void *)&vbuf32[i-1], ~pat, vbuf32[i-1]);
+            return ERR_GENERIC;
+        }
+
+        vbuf32[i-1] = pat;
+    }
+
+    /* verify that we have the original pattern */
+    //printf("\t\tfinal test\n");
+    for (i = 0; i < len / 4; i++) {
+        if (vbuf32[i] != pat) {
+            mem_test_fail((void *)&vbuf32[i], pat, vbuf32[i]);
+            return ERR_GENERIC;
+        }
+    }
+
+    return NO_ERROR;
+}
+
+static void do_mem_tests(void *ptr, size_t len)
+{
+    size_t i;
+
+    /* test 1: simple write address to memory, read back */
+    printf("test 1: simple address write, read back\n");
+    volatile uint32_t *vbuf32 = ptr;
+    for (i = 0; i < len / 4; i++) {
+        vbuf32[i] = i;
+    }
+
+    for (i = 0; i < len / 4; i++) {
+        if (vbuf32[i] != i) {
+            mem_test_fail((void *)&vbuf32[i], i, vbuf32[i]);
+            goto out;
+        }
+    }
+
+    /* test 2: write various patterns, read back */
+    printf("test 2: write patterns, read back\n");
+
+    static const uint32_t pat[] = {
+        0x0, 0xffffffff,
+        0xaaaaaaaa, 0x55555555,
+    };
+
+    for (size_t p = 0; p < countof(pat); p++) {
+        if (do_pattern_test(ptr, len, pat[p]) < 0)
+            goto out;
+    }
+    // shift bits through 32bit word
+    for (uint32_t p = 1; p != 0; p <<= 1) {
+        if (do_pattern_test(ptr, len, p) < 0)
+            goto out;
+    }
+    // shift bits through 16bit word, invert top of 32bit
+    for (uint16_t p = 1; p != 0; p <<= 1) {
+        if (do_pattern_test(ptr, len, ((~p) << 16) | p) < 0)
+            goto out;
+    }
+
+    /* test 3: moving inversion, patterns */
+    printf("test 3: moving inversions with patterns\n");
+    for (size_t p = 0; p < countof(pat); p++) {
+        if (do_moving_inversion_test(ptr, len, pat[p]) < 0)
+            goto out;
+
+    }
+    // shift bits through 32bit word
+    for (uint32_t p = 1; p != 0; p <<= 1) {
+        if (do_moving_inversion_test(ptr, len, p) < 0)
+            goto out;
+    }
+    // shift bits through 16bit word, invert top of 32bit
+    for (uint16_t p = 1; p != 0; p <<= 1) {
+        if (do_moving_inversion_test(ptr, len, ((~p) << 16) | p) < 0)
+            goto out;
+    }
+
+out:
+    printf("done with tests\n");
+}
+
+static int mem_test(int argc, const cmd_args *argv)
+{
+    if (argc < 2) {
+        printf("not enough arguments\n");
+usage:
+        printf("usage: %s <length>\n", argv[0].str);
+        return -1;
+    }
+
+    void *ptr;
+    size_t len = argv[1].u;
+
+#if WITH_KERNEL_VM
+    /* rounding up len to the next page */
+    len = PAGE_ALIGN(len);
+    if (len == 0) {
+        printf("invalid length\n");
+        goto usage;
+    }
+
+    /* allocate a region to test in */
+    status_t err = vmm_alloc_contiguous(vmm_get_kernel_aspace(), "memtest", len, &ptr, 0, 0, ARCH_MMU_FLAG_UNCACHED);
+    if (err < 0) {
+        printf("error %d allocating test region\n", err);
+        return -1;
+    }
+
+    paddr_t pa;
+    arch_mmu_query((vaddr_t)ptr, &pa, 0);
+    printf("physical address 0x%lx\n", pa);
+#else
+    /* allocate from the heap */
+    ptr = malloc(len);
+    if (!ptr ) {
+        printf("error allocating test area from heap\n");
+        return -1;
+    }
+
+#endif
+
+    printf("got buffer at %p of length 0x%lx\n", ptr, len);
+
+    /* run the tests */
+    do_mem_tests(ptr, len);
+
+#if WITH_KERNEL_VM
+    // XXX free memory region here
+    printf("NOTE: leaked memory\n");
+#else
+    free(ptr);
+#endif
+
+    return 0;
+}
+
+STATIC_COMMAND_START
+STATIC_COMMAND("mem_test", "test memory", &mem_test)
+STATIC_COMMAND_END(mem_tests);
+

app/tests/rules.mk

@@ -14,7 +14,8 @@ MODULE_SRCS += \
 	$(LOCAL_DIR)/float.c \
 	$(LOCAL_DIR)/float_instructions.S \
 	$(LOCAL_DIR)/float_test_vec.c \
-	$(LOCAL_DIR)/fibo.c
+	$(LOCAL_DIR)/fibo.c \
+	$(LOCAL_DIR)/mem_tests.c
 
 MODULE_COMPILEFLAGS += -Wno-format