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authorChristian Mauderer <Christian.Mauderer@embedded-brains.de>2017-11-13 09:21:31 +0100
committerSebastian Huber <sebastian.huber@embedded-brains.de>2017-11-17 07:26:57 +0100
commita9de9a7b95b2e775d7a693782f041abb2b9caa75 (patch)
tree1280fcbbbd2bb2b0e4c5f8b0efab7e7e00a1d31e
parentgetentropy: Add test. (diff)
downloadrtems-a9de9a7b95b2e775d7a693782f041abb2b9caa75.tar.bz2
bsp/atsam: Add getentropy().
Update #3239.
-rw-r--r--c/src/lib/libbsp/arm/atsam/Makefile.am2
-rw-r--r--c/src/lib/libbsp/arm/atsam/startup/getentropy-trng.c61
2 files changed, 62 insertions, 1 deletions
diff --git a/c/src/lib/libbsp/arm/atsam/Makefile.am b/c/src/lib/libbsp/arm/atsam/Makefile.am
index d29ba0895a..d44a72269e 100644
--- a/c/src/lib/libbsp/arm/atsam/Makefile.am
+++ b/c/src/lib/libbsp/arm/atsam/Makefile.am
@@ -332,7 +332,6 @@ libbsp_a_LIBADD =
# Shared
libbsp_a_SOURCES += ../../shared/bootcard.c
-libbsp_a_SOURCES += ../../shared/getentropy-cpucounter.c
libbsp_a_SOURCES += ../../shared/bspclean.c
libbsp_a_SOURCES += ../../shared/bspgetworkarea.c
libbsp_a_SOURCES += ../../shared/bsppredriverhook.c
@@ -397,6 +396,7 @@ libbsp_a_SOURCES += ../shared/armv7m/startup/bspreset.c
libbsp_a_SOURCES += ../shared/armv7m/startup/armv7m-cpucounter.c
libbsp_a_SOURCES += startup/bspstart.c
libbsp_a_SOURCES += startup/bspstarthooks.c
+libbsp_a_SOURCES += startup/getentropy-trng.c
libbsp_a_SOURCES += startup/pin-config.c
libbsp_a_SOURCES += startup/power.c
libbsp_a_SOURCES += startup/power-rtc.c
diff --git a/c/src/lib/libbsp/arm/atsam/startup/getentropy-trng.c b/c/src/lib/libbsp/arm/atsam/startup/getentropy-trng.c
new file mode 100644
index 0000000000..11e24dcda1
--- /dev/null
+++ b/c/src/lib/libbsp/arm/atsam/startup/getentropy-trng.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2017 embedded brains GmbH. All rights reserved.
+ *
+ * embedded brains GmbH
+ * Dornierstr. 4
+ * 82178 Puchheim
+ * Germany
+ * <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#include <libchip/chip.h>
+#include <unistd.h>
+#include <string.h>
+#include <rtems/sysinit.h>
+
+static void atsam_trng_enable(void)
+{
+ PMC_EnablePeripheral(ID_TRNG);
+ TRNG_Enable();
+}
+
+int getentropy(void *ptr, size_t n)
+{
+ while (n > 0) {
+ uint32_t random;
+ size_t copy;
+
+ while ((TRNG_GetStatus() & TRNG_ISR_DATRDY) == 0) {
+ /* wait */
+ }
+ random = TRNG_GetRandData();
+
+ /*
+ * Read TRNG status one more time to avoid race condition.
+ * Otherwise we can read (and clear) an old ready status but get
+ * a new value. The ready status for this value wouldn't be
+ * reset.
+ */
+ TRNG_GetStatus();
+
+ copy = sizeof(random);
+ if (n < copy ) {
+ copy = n;
+ }
+ memcpy(ptr, &random, copy);
+ n -= copy;
+ ptr += copy;
+ }
+
+ return 0;
+}
+
+RTEMS_SYSINIT_ITEM(
+ atsam_trng_enable,
+ RTEMS_SYSINIT_DEVICE_DRIVERS,
+ RTEMS_SYSINIT_ORDER_LAST
+);