ec: add crc32_ctx..() to take context parameter.

Add crc32_ctx.. functions to take context parameter.

This allows for multiple instances to exist in parallel.

Signed-off-by: mschilder@google.com
TEST=make buildall -j8 succeeds
BRANCH=none
BUG=b:73832883

Change-Id: I66bbc56377eeebf01c790caad0bc4c7a51a1bc58
Reviewed-on: https://chromium-review.googlesource.com/935825
Commit-Ready: Marius Schilder <mschilder@chromium.org>
Tested-by: Marius Schilder <mschilder@chromium.org>
Reviewed-by: Marius Schilder <mschilder@chromium.org>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>

6 files changed, 144 insertions, 7 deletions

diff --git a/common/crc.c b/common/crc.c
index 31054ad732..79d405eb13 100644
--- a/common/crc.c
+++ b/common/crc.c
@@ -56,9 +56,6 @@ static const uint32_t crc32_tab[] = {
 	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
 };
 
-/* Accumulator for the CRC */
-static uint32_t crc_;
-
 static uint32_t crc32_hash(uint32_t crc, const void *buf, int size)
 {
 	const uint8_t *p;
@@ -73,22 +70,50 @@ static uint32_t crc32_hash(uint32_t crc, const void *buf, int size)
 	return crc;
 }
 
+void crc32_ctx_init(uint32_t *crc)
+{
+	*crc = CRC32_INITIAL;
+}
+
+void crc32_ctx_hash32(uint32_t *crc, uint32_t val)
+{
+	*crc = crc32_hash(*crc, &val, sizeof(val));
+}
+
+void crc32_ctx_hash16(uint32_t *crc, uint16_t val)
+{
+	*crc = crc32_hash(*crc, &val, sizeof(val));
+}
+
+void crc32_ctx_hash8(uint32_t *crc, uint8_t val)
+{
+	*crc = crc32_hash(*crc, &val, sizeof(val));
+}
+
+uint32_t crc32_ctx_result(uint32_t *crc)
+{
+	return *crc ^ 0xFFFFFFFF;
+}
+
+/* Accumulator for the CRC */
+static uint32_t crc_;
+
 void crc32_init(void)
 {
-	crc_ = CRC32_INITIAL;
+	crc32_ctx_init(&crc_);
 }
 
 void crc32_hash32(uint32_t val)
 {
-	crc_ = crc32_hash(crc_, &val, sizeof(uint32_t));
+	crc32_ctx_hash32(&crc_, val);
 }
 
 void crc32_hash16(uint16_t val)
 {
-	crc_ = crc32_hash(crc_, &val, sizeof(uint16_t));
+	crc32_ctx_hash16(&crc_, val);
 }
 
 uint32_t crc32_result(void)
 {
-	return crc_ ^ 0xFFFFFFFF;
+	return crc32_ctx_result(&crc_);
 }
diff --git a/include/crc.h b/include/crc.h
index 6615885f27..e3b5e4ffd1 100644
--- a/include/crc.h
+++ b/include/crc.h
@@ -14,6 +14,8 @@
 
 /* Use software implementation */
 
+/* Static context variant */
+
 void crc32_init(void);
 
 void crc32_hash32(uint32_t val);
@@ -22,6 +24,18 @@ void crc32_hash16(uint16_t val);
 
 uint32_t crc32_result(void);
 
+/* Provided context variant */
+
+void crc32_ctx_init(uint32_t *ctx);
+
+void crc32_ctx_hash32(uint32_t *ctx, uint32_t val);
+
+void crc32_ctx_hash16(uint32_t *ctx, uint16_t val);
+
+void crc32_ctx_hash8(uint32_t *ctx, uint8_t val);
+
+uint32_t crc32_ctx_result(uint32_t *ctx);
+
 #endif /* CONFIG_HW_CRC */
 
 #endif /* __CROS_EC_CRC_H */
diff --git a/test/build.mk b/test/build.mk
index 9c5dd53349..2bcd163655 100644
--- a/test/build.mk
+++ b/test/build.mk
@@ -39,6 +39,7 @@ test-list-host += charge_manager
 test-list-host += charge_manager_drp_charging
 test-list-host += charge_ramp
 test-list-host += console_edit
+test-list-host += crc32
 test-list-host += entropy
 test-list-host += extpwr_gpio
 test-list-host += fan
@@ -89,6 +90,7 @@ charge_manager-y=charge_manager.o
 charge_manager_drp_charging-y=charge_manager.o
 charge_ramp-y+=charge_ramp.o
 console_edit-y=console_edit.o
+crc32-y=crc32.o
 entropy-y=entropy.o
 extpwr_gpio-y=extpwr_gpio.o
 fan-y=fan.o
diff --git a/test/crc32.c b/test/crc32.c
new file mode 100644
index 0000000000..e3f6f8d5c6
--- /dev/null
+++ b/test/crc32.c
@@ -0,0 +1,75 @@
+/* Copyright 2016 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Tests crc32 sw implementation.
+ */
+
+#include "common.h"
+#include "console.h"
+#include "crc.h"
+#include "test_util.h"
+#include "util.h"
+
+// test that static version matches context version
+static int test_static(void)
+{
+	uint32_t crc;
+	const uint32_t input = 0xdeadbeef;
+
+	crc32_init();
+	crc32_hash32(input);
+
+	crc32_ctx_init(&crc);
+	crc32_ctx_hash32(&crc, input);
+
+	TEST_ASSERT(crc32_result() == crc32_ctx_result(&crc));
+
+	return EC_SUCCESS;
+}
+
+// test that context bytes at a time matches static word at time
+static int test_8(void)
+{
+	uint32_t crc;
+	const uint32_t input = 0xdeadbeef;
+	const uint8_t *p = (const uint8_t *) &input;
+	int i;
+
+	crc32_init();
+	crc32_hash32(input);
+
+	crc32_ctx_init(&crc);
+	for (i = 0; i < sizeof(input); ++i)
+		crc32_ctx_hash8(&crc, p[i]);
+
+	TEST_ASSERT(crc32_result() == crc32_ctx_result(&crc));
+
+	return EC_SUCCESS;
+}
+
+// http://www.febooti.com/products/filetweak/members/hash-and-crc/test-vectors/
+static int test_kat0(void)
+{
+	uint32_t crc;
+	int i;
+	const char input[] = "The quick brown fox jumps over the lazy dog";
+
+	crc32_ctx_init(&crc);
+	for (i = 0; i < strlen(input); ++i)
+		crc32_ctx_hash8(&crc, input[i]);
+	TEST_ASSERT(crc32_ctx_result(&crc) == 0x414fa339);
+
+	return EC_SUCCESS;
+}
+
+void run_test(void)
+{
+	test_reset();
+
+	RUN_TEST(test_static);
+	RUN_TEST(test_8);
+	RUN_TEST(test_kat0);
+
+	test_print_result();
+}
diff --git a/test/crc32.tasklist b/test/crc32.tasklist
new file mode 100644
index 0000000000..30e5f7fc22
--- /dev/null
+++ b/test/crc32.tasklist
@@ -0,0 +1,17 @@
+/* Copyright 2016 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/**
+ * List of enabled tasks in the priority order
+ *
+ * The first one has the lowest priority.
+ *
+ * For each task, use the macro TASK_TEST(n, r, d, s) where :
+ * 'n' in the name of the task
+ * 'r' in the main routine of the task
+ * 'd' in an opaque parameter passed to the routine at startup
+ * 's' is the stack size in bytes; must be a multiple of 8
+ */
+#define CONFIG_TEST_TASK_LIST
diff --git a/test/test_config.h b/test/test_config.h
index e784bb8b2e..f46e61443f 100644
--- a/test/test_config.h
+++ b/test/test_config.h
@@ -84,6 +84,10 @@
 
 #endif
 
+#ifdef TEST_CRC32
+#define CONFIG_SW_CRC
+#endif
+
 #ifdef TEST_RSA
 #define CONFIG_RSA
 #define CONFIG_RSA_KEY_SIZE 2048