qti: Add RNG driver
This patch adds RNG driver and use it to generate random number for stack
protection.
Change-Id: I73d79e68d08b5aa902dc7fad48e17a03f996178d
Signed-off-by: Saurabh Gorecha <sgorecha@codeaurora.org>
diff --git a/plat/qti/common/inc/qti_rng.h b/plat/qti/common/inc/qti_rng.h
new file mode 100644
index 0000000..c933dea
--- /dev/null
+++ b/plat/qti/common/inc/qti_rng.h
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef QTI_RNG_H
+#define QTI_RNG_H
+
+#include <stdinit.h>
+
+int qti_rng_get_data(uint8_t *out, uint32_t out_len);
+
+#endif /* QTI_RNG_H */
diff --git a/plat/qti/common/src/qti_rng.c b/plat/qti/common/src/qti_rng.c
new file mode 100644
index 0000000..a904209
--- /dev/null
+++ b/plat/qti/common/src/qti_rng.c
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#include <stddef.h>
+#include <stdint.h>
+
+#include <lib/mmio.h>
+
+#include <qti_rng_io.h>
+
+int qti_rng_get_data(uint8_t *out, uint32_t out_len)
+{
+ uint32_t tmp_rndm = 0;
+ uint32_t bytes_left = out_len;
+ int i = 0;
+
+ if (NULL == out || 0 == out_len) {
+ return -1;
+ }
+
+ /*
+ * RNG HW initialized at previous boot image.
+ * RNG clocks are expected to be ON.
+ */
+
+ do {
+ /* There is no data to read */
+ if ((mmio_read_32(SEC_PRNG_STATUS) &
+ SEC_PRNG_STATUS_DATA_AVAIL_BMSK) == 0) {
+ continue;
+ }
+
+ while ((tmp_rndm = mmio_read_32(SEC_PRNG_DATA_OUT)) == 0) {
+ ;
+ }
+
+ for (i = 0; i < 4; i++) {
+ *out = (uint8_t) (tmp_rndm >> (8 * i));
+
+ out++;
+ bytes_left--;
+
+ if (bytes_left == 0) {
+ break;
+ }
+ }
+
+ } while (bytes_left != 0);
+
+ return 0;
+}
diff --git a/plat/qti/common/src/qti_stack_protector.c b/plat/qti/common/src/qti_stack_protector.c
index b2dbfb0..572830f 100644
--- a/plat/qti/common/src/qti_stack_protector.c
+++ b/plat/qti/common/src/qti_stack_protector.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2018-2019, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -9,16 +9,18 @@
#include <platform.h>
#include <platform_def.h>
+#include <qti_rng.h>
#include <qtiseclib_interface.h>
u_register_t plat_get_stack_protector_canary(void)
{
u_register_t random = 0x0;
- /* get random data , the below API doesn't return random = 0 in success
- * case */
- qtiseclib_prng_get_data((uint8_t *) &random, sizeof(random));
- assert(0x0 != random);
+ /*
+ * get random data , the below API doesn't return random = 0 on success
+ */
+ qti_rng_get_data((uint8_t *) &random, sizeof(random));
+ assert(random != 0x0);
return random;
}
diff --git a/plat/qti/qtiseclib/inc/qtiseclib_interface.h b/plat/qti/qtiseclib/inc/qtiseclib_interface.h
index edabc5b..357bb6a 100644
--- a/plat/qti/qtiseclib/inc/qtiseclib_interface.h
+++ b/plat/qti/qtiseclib/inc/qtiseclib_interface.h
@@ -63,7 +63,6 @@
void qtiseclib_bl31_platform_setup(void);
void qtiseclib_invoke_isr(uint32_t irq, void *handle);
void qtiseclib_panic(void);
-int qtiseclib_prng_get_data(uint8_t *out, uint32_t out_len);
int qtiseclib_mem_assign(const memprot_info_t *mem_info,
uint32_t mem_info_list_cnt,
diff --git a/plat/qti/qtiseclib/src/qtiseclib_interface_stub.c b/plat/qti/qtiseclib/src/qtiseclib_interface_stub.c
index 494083b..70485fe 100644
--- a/plat/qti/qtiseclib/src/qtiseclib_interface_stub.c
+++ b/plat/qti/qtiseclib/src/qtiseclib_interface_stub.c
@@ -67,17 +67,6 @@
{
}
-int qtiseclib_prng_get_data(uint8_t *out, uint32_t out_len)
-{
- /* fill dummy data to avoid assert and print
- * stub implementation in setup call
- */
- for (int i = 0; i < out_len; i++) {
- out[i] = 0x11;
- }
- return 0;
-}
-
int
qtiseclib_mem_assign(const memprot_info_t *mem_info,
uint32_t mem_info_list_cnt,
diff --git a/plat/qti/sc7180/inc/qti_rng_io.h b/plat/qti/sc7180/inc/qti_rng_io.h
new file mode 100644
index 0000000..f50234f
--- /dev/null
+++ b/plat/qti/sc7180/inc/qti_rng_io.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#ifndef QTI_RNG_IO_H
+#define QTI_RNG_IO_H
+
+#define SEC_PRNG_STATUS 0x00791004
+#define SEC_PRNG_STATUS_DATA_AVAIL_BMSK 0x1
+#define SEC_PRNG_DATA_OUT 0x00791000
+
+
+#endif /* QTI_RNG_IO_H */
+
diff --git a/plat/qti/sc7180/platform.mk b/plat/qti/sc7180/platform.mk
index 45e6b33..e551355 100644
--- a/plat/qti/sc7180/platform.mk
+++ b/plat/qti/sc7180/platform.mk
@@ -59,6 +59,7 @@
$(QTI_PLAT_PATH)/common/src/qti_syscall.c \
$(QTI_PLAT_PATH)/common/src/qti_topology.c \
$(QTI_PLAT_PATH)/common/src/qti_pm.c \
+ $(QTI_PLAT_PATH)/common/src/qti_rng.c \
$(QTI_PLAT_PATH)/qtiseclib/src/qtiseclib_cb_interface.c \