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authorLinus Torvalds2019-03-06 09:41:12 -0800
committerLinus Torvalds2019-03-06 09:41:12 -0800
commit384d11fa0e2ca15a3e7e52db34a4e43bedf0dc70 (patch)
treeb68ecd9458fb77d6b80e1389fc3705ca360a7def /drivers/char/hw_random
parent6ad63dec9c2c80710896edd1996e56c54a230870 (diff)
parent8ceb820b69fe6ff58234ff604146a9e88e6c1974 (diff)
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC driver updates from Arnd Bergmann: "As usual, the drivers/tee and drivers/reset subsystems get merged here, with the expected set of smaller updates and some new hardware support. The tee subsystem now supports device drivers to be attached to a tee, the first example here is a random number driver with its implementation in the secure world. Three new power domain drivers get added for specific chip families: - Broadcom BCM283x chips (used in Raspberry Pi) - Qualcomm Snapdragon phone chips - Xilinx ZynqMP FPGA SoCs One new driver is added to talk to the BPMP firmware on NVIDIA Tegra210 Existing drivers are extended for new SoC variants from NXP, NVIDIA, Amlogic and Qualcomm" * tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (113 commits) tee: optee: update optee_msg.h and optee_smc.h to dual license tee: add cancellation support to client interface dpaa2-eth: configure the cache stashing amount on a queue soc: fsl: dpio: configure cache stashing destination soc: fsl: dpio: enable frame data cache stashing per software portal soc: fsl: guts: make fsl_guts_get_svr() static hwrng: make symbol 'optee_rng_id_table' static tee: optee: Fix unsigned comparison with less than zero hwrng: Fix unsigned comparison with less than zero tee: fix possible error pointer ctx dereferencing hwrng: optee: Initialize some structs using memset instead of braces tee: optee: Initialize some structs using memset instead of braces soc: fsl: dpio: fix memory leak of a struct qbman on error exit path clk: tegra: dfll: Make symbol 'tegra210_cpu_cvb_tables' static soc: qcom: llcc-slice: Fix typos qcom: soc: llcc-slice: Consolidate some code qcom: soc: llcc-slice: Clear the global drv_data pointer on error drivers: soc: xilinx: Add ZynqMP power domain driver firmware: xilinx: Add APIs to control node status/power dt-bindings: power: Add ZynqMP power domain bindings ...
Diffstat (limited to 'drivers/char/hw_random')
-rw-r--r--drivers/char/hw_random/Kconfig15
-rw-r--r--drivers/char/hw_random/Makefile1
-rw-r--r--drivers/char/hw_random/optee-rng.c306
3 files changed, 322 insertions, 0 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index dac895dc01b9..25a7d8ffdb5d 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -424,6 +424,21 @@ config HW_RANDOM_EXYNOS
will be called exynos-trng.
If unsure, say Y.
+
+config HW_RANDOM_OPTEE
+ tristate "OP-TEE based Random Number Generator support"
+ depends on OPTEE
+ default HW_RANDOM
+ help
+ This driver provides support for OP-TEE based Random Number
+ Generator on ARM SoCs where hardware entropy sources are not
+ accessible to normal world (Linux).
+
+ To compile this driver as a module, choose M here: the module
+ will be called optee-rng.
+
+ If unsure, say Y.
+
endif # HW_RANDOM
config UML_RANDOM
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index e35ec3ce3a20..7c9ef4a7667f 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -38,3 +38,4 @@ obj-$(CONFIG_HW_RANDOM_CAVIUM) += cavium-rng.o cavium-rng-vf.o
obj-$(CONFIG_HW_RANDOM_MTK) += mtk-rng.o
obj-$(CONFIG_HW_RANDOM_S390) += s390-trng.o
obj-$(CONFIG_HW_RANDOM_KEYSTONE) += ks-sa-rng.o
+obj-$(CONFIG_HW_RANDOM_OPTEE) += optee-rng.o
diff --git a/drivers/char/hw_random/optee-rng.c b/drivers/char/hw_random/optee-rng.c
new file mode 100644
index 000000000000..ddfbabaa5f8f
--- /dev/null
+++ b/drivers/char/hw_random/optee-rng.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018-2019 Linaro Ltd.
+ */
+
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/hw_random.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/uuid.h>
+
+#define DRIVER_NAME "optee-rng"
+
+#define TEE_ERROR_HEALTH_TEST_FAIL 0x00000001
+
+/*
+ * TA_CMD_GET_ENTROPY - Get Entropy from RNG
+ *
+ * param[0] (inout memref) - Entropy buffer memory reference
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ * TEE_ERROR_NOT_SUPPORTED - Requested entropy size greater than size of pool
+ * TEE_ERROR_HEALTH_TEST_FAIL - Continuous health testing failed
+ */
+#define TA_CMD_GET_ENTROPY 0x0
+
+/*
+ * TA_CMD_GET_RNG_INFO - Get RNG information
+ *
+ * param[0] (out value) - value.a: RNG data-rate in bytes per second
+ * value.b: Quality/Entropy per 1024 bit of data
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+#define TA_CMD_GET_RNG_INFO 0x1
+
+#define MAX_ENTROPY_REQ_SZ (4 * 1024)
+
+/**
+ * struct optee_rng_private - OP-TEE Random Number Generator private data
+ * @dev: OP-TEE based RNG device.
+ * @ctx: OP-TEE context handler.
+ * @session_id: RNG TA session identifier.
+ * @data_rate: RNG data rate.
+ * @entropy_shm_pool: Memory pool shared with RNG device.
+ * @optee_rng: OP-TEE RNG driver structure.
+ */
+struct optee_rng_private {
+ struct device *dev;
+ struct tee_context *ctx;
+ u32 session_id;
+ u32 data_rate;
+ struct tee_shm *entropy_shm_pool;
+ struct hwrng optee_rng;
+};
+
+#define to_optee_rng_private(r) \
+ container_of(r, struct optee_rng_private, optee_rng)
+
+static size_t get_optee_rng_data(struct optee_rng_private *pvt_data,
+ void *buf, size_t req_size)
+{
+ int ret = 0;
+ u8 *rng_data = NULL;
+ size_t rng_size = 0;
+ struct tee_ioctl_invoke_arg inv_arg;
+ struct tee_param param[4];
+
+ memset(&inv_arg, 0, sizeof(inv_arg));
+ memset(&param, 0, sizeof(param));
+
+ /* Invoke TA_CMD_GET_ENTROPY function of Trusted App */
+ inv_arg.func = TA_CMD_GET_ENTROPY;
+ inv_arg.session = pvt_data->session_id;
+ inv_arg.num_params = 4;
+
+ /* Fill invoke cmd params */
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT;
+ param[0].u.memref.shm = pvt_data->entropy_shm_pool;
+ param[0].u.memref.size = req_size;
+ param[0].u.memref.shm_offs = 0;
+
+ ret = tee_client_invoke_func(pvt_data->ctx, &inv_arg, param);
+ if ((ret < 0) || (inv_arg.ret != 0)) {
+ dev_err(pvt_data->dev, "TA_CMD_GET_ENTROPY invoke err: %x\n",
+ inv_arg.ret);
+ return 0;
+ }
+
+ rng_data = tee_shm_get_va(pvt_data->entropy_shm_pool, 0);
+ if (IS_ERR(rng_data)) {
+ dev_err(pvt_data->dev, "tee_shm_get_va failed\n");
+ return 0;
+ }
+
+ rng_size = param[0].u.memref.size;
+ memcpy(buf, rng_data, rng_size);
+
+ return rng_size;
+}
+
+static int optee_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
+{
+ struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
+ size_t read = 0, rng_size = 0;
+ int timeout = 1;
+ u8 *data = buf;
+
+ if (max > MAX_ENTROPY_REQ_SZ)
+ max = MAX_ENTROPY_REQ_SZ;
+
+ while (read == 0) {
+ rng_size = get_optee_rng_data(pvt_data, data, (max - read));
+
+ data += rng_size;
+ read += rng_size;
+
+ if (wait) {
+ if (timeout-- == 0)
+ return read;
+ msleep((1000 * (max - read)) / pvt_data->data_rate);
+ } else {
+ return read;
+ }
+ }
+
+ return read;
+}
+
+static int optee_rng_init(struct hwrng *rng)
+{
+ struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
+ struct tee_shm *entropy_shm_pool = NULL;
+
+ entropy_shm_pool = tee_shm_alloc(pvt_data->ctx, MAX_ENTROPY_REQ_SZ,
+ TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
+ if (IS_ERR(entropy_shm_pool)) {
+ dev_err(pvt_data->dev, "tee_shm_alloc failed\n");
+ return PTR_ERR(entropy_shm_pool);
+ }
+
+ pvt_data->entropy_shm_pool = entropy_shm_pool;
+
+ return 0;
+}
+
+static void optee_rng_cleanup(struct hwrng *rng)
+{
+ struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
+
+ tee_shm_free(pvt_data->entropy_shm_pool);
+}
+
+static struct optee_rng_private pvt_data = {
+ .optee_rng = {
+ .name = DRIVER_NAME,
+ .init = optee_rng_init,
+ .cleanup = optee_rng_cleanup,
+ .read = optee_rng_read,
+ }
+};
+
+static int get_optee_rng_info(struct device *dev)
+{
+ int ret = 0;
+ struct tee_ioctl_invoke_arg inv_arg;
+ struct tee_param param[4];
+
+ memset(&inv_arg, 0, sizeof(inv_arg));
+ memset(&param, 0, sizeof(param));
+
+ /* Invoke TA_CMD_GET_RNG_INFO function of Trusted App */
+ inv_arg.func = TA_CMD_GET_RNG_INFO;
+ inv_arg.session = pvt_data.session_id;
+ inv_arg.num_params = 4;
+
+ /* Fill invoke cmd params */
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+
+ ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
+ if ((ret < 0) || (inv_arg.ret != 0)) {
+ dev_err(dev, "TA_CMD_GET_RNG_INFO invoke err: %x\n",
+ inv_arg.ret);
+ return -EINVAL;
+ }
+
+ pvt_data.data_rate = param[0].u.value.a;
+ pvt_data.optee_rng.quality = param[0].u.value.b;
+
+ return 0;
+}
+
+static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+ if (ver->impl_id == TEE_IMPL_ID_OPTEE)
+ return 1;
+ else
+ return 0;
+}
+
+static int optee_rng_probe(struct device *dev)
+{
+ struct tee_client_device *rng_device = to_tee_client_device(dev);
+ int ret = 0, err = -ENODEV;
+ struct tee_ioctl_open_session_arg sess_arg;
+
+ memset(&sess_arg, 0, sizeof(sess_arg));
+
+ /* Open context with TEE driver */
+ pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL,
+ NULL);
+ if (IS_ERR(pvt_data.ctx))
+ return -ENODEV;
+
+ /* Open session with hwrng Trusted App */
+ memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
+ sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
+ sess_arg.num_params = 0;
+
+ ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL);
+ if ((ret < 0) || (sess_arg.ret != 0)) {
+ dev_err(dev, "tee_client_open_session failed, err: %x\n",
+ sess_arg.ret);
+ err = -EINVAL;
+ goto out_ctx;
+ }
+ pvt_data.session_id = sess_arg.session;
+
+ err = get_optee_rng_info(dev);
+ if (err)
+ goto out_sess;
+
+ err = hwrng_register(&pvt_data.optee_rng);
+ if (err) {
+ dev_err(dev, "hwrng registration failed (%d)\n", err);
+ goto out_sess;
+ }
+
+ pvt_data.dev = dev;
+
+ return 0;
+
+out_sess:
+ tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
+out_ctx:
+ tee_client_close_context(pvt_data.ctx);
+
+ return err;
+}
+
+static int optee_rng_remove(struct device *dev)
+{
+ hwrng_unregister(&pvt_data.optee_rng);
+ tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
+ tee_client_close_context(pvt_data.ctx);
+
+ return 0;
+}
+
+static const struct tee_client_device_id optee_rng_id_table[] = {
+ {UUID_INIT(0xab7a617c, 0xb8e7, 0x4d8f,
+ 0x83, 0x01, 0xd0, 0x9b, 0x61, 0x03, 0x6b, 0x64)},
+ {}
+};
+
+MODULE_DEVICE_TABLE(tee, optee_rng_id_table);
+
+static struct tee_client_driver optee_rng_driver = {
+ .id_table = optee_rng_id_table,
+ .driver = {
+ .name = DRIVER_NAME,
+ .bus = &tee_bus_type,
+ .probe = optee_rng_probe,
+ .remove = optee_rng_remove,
+ },
+};
+
+static int __init optee_rng_mod_init(void)
+{
+ return driver_register(&optee_rng_driver.driver);
+}
+
+static void __exit optee_rng_mod_exit(void)
+{
+ driver_unregister(&optee_rng_driver.driver);
+}
+
+module_init(optee_rng_mod_init);
+module_exit(optee_rng_mod_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Sumit Garg <sumit.garg@linaro.org>");
+MODULE_DESCRIPTION("OP-TEE based random number generator driver");