Re: [PATCH] firmware: broadcom: add OP-TEE based BNXT f/w manager

From: Ray Jui
Date: Wed Sep 11 2019 - 13:56:39 EST



On 9/11/19 10:53 AM, Sheetal Tigadoli wrote:
Thanks for the review and comments.

On Tue, Sep 10, 2019 at 10:46 PM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:

On Tue, Sep 10, 2019 at 08:47:04PM +0530, Sheetal Tigadoli wrote:
From: Vikas Gupta <vikas.gupta@xxxxxxxxxxxx>

This driver registers on TEE bus to interact with OP-TEE based
BNXT firmware management modules

Signed-off-by: Vikas Gupta <vikas.gupta@xxxxxxxxxxxx>
Signed-off-by: Sheetal Tigadoli <sheetal.tigadoli@xxxxxxxxxxxx>
---
drivers/firmware/broadcom/Kconfig | 8 +
drivers/firmware/broadcom/Makefile | 1 +
drivers/firmware/broadcom/tee_bnxt_fw.c | 447 ++++++++++++++++++++++++++
include/linux/firmware/broadcom/tee_bnxt_fw.h | 17 +
4 files changed, 473 insertions(+)
create mode 100644 drivers/firmware/broadcom/tee_bnxt_fw.c
create mode 100644 include/linux/firmware/broadcom/tee_bnxt_fw.h

diff --git a/drivers/firmware/broadcom/Kconfig b/drivers/firmware/broadcom/Kconfig
index 6468082..a846a21 100644
--- a/drivers/firmware/broadcom/Kconfig
+++ b/drivers/firmware/broadcom/Kconfig
@@ -22,3 +22,11 @@ config BCM47XX_SPROM
In case of SoC devices SPROM content is stored on a flash used by
bootloader firmware CFE. This driver provides method to ssb and bcma
drivers to read SPROM on SoC.
+
+config TEE_BNXT_FW
+ bool "Broadcom BNXT firmware manager"
+ depends on ARCH_BCM_IPROC && OPTEE

No ability to build with compile testing?
Will add "|| COMPILE_TEST"

+ default ARCH_BCM_IPROC
+ help
+ This module help to manage firmware on Broadcom BNXT device. The module
+ registers on tee bus and invoke calls to manage firmware on BNXT device.
diff --git a/drivers/firmware/broadcom/Makefile b/drivers/firmware/broadcom/Makefile
index 72c7fdc..17c5061 100644
--- a/drivers/firmware/broadcom/Makefile
+++ b/drivers/firmware/broadcom/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_BCM47XX_NVRAM) += bcm47xx_nvram.o
obj-$(CONFIG_BCM47XX_SPROM) += bcm47xx_sprom.o
+obj-$(CONFIG_TEE_BNXT_FW) += tee_bnxt_fw.o
diff --git a/drivers/firmware/broadcom/tee_bnxt_fw.c b/drivers/firmware/broadcom/tee_bnxt_fw.c
new file mode 100644
index 00000000..89a48fd
--- /dev/null
+++ b/drivers/firmware/broadcom/tee_bnxt_fw.c
@@ -0,0 +1,447 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Broadcom.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/uuid.h>
+
+#include <linux/firmware/broadcom/tee_bnxt_fw.h>
+
+#define DRIVER_NAME "tee-bnxt-fw"

KBUILD_MODNAME?
Will remove DRIVER_NAME macro and use KBUILD_MODNAME instead.

+#define MAX_SHM_MEM_SZ SZ_4M

Why?
Limiting max data buffer size per request to optee to 4MB.

+
+#define MAX_TEE_PARAM_ARRY_MEMB 4
+
+enum ta_cmd {
+/*
+ * TA_CMD_BNXT_FASTBOOT - boot bnxt device by copying f/w into sram
+ *
+ * param[0] unused
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_ITEM_NOT_FOUND - Corrupt f/w image found on memory
+ */
+ TA_CMD_BNXT_FASTBOOT = 0,
+

Please indent the comments too. As-is this is hard to read.
Will do


+/*
+ * TA_CMD_BNXT_HEALTH_STATUS - to check health of bnxt device
+ *
+ * param[0] (out value) - value.a: health status
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+ TA_CMD_BNXT_HEALTH_STATUS,

Should all of these have explicit values?
Will initialize each cmd (TA_CMD_BNXT_*) explicitly

+
+/*
+ * TA_CMD_BNXT_HANDSHAKE - to check bnxt device is booted
+ *
+ * param[0] (in value) - value.a: max timeout value
+ * param[0] (out value) - value.a: boot status
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+ TA_CMD_BNXT_HANDSHAKE,
+
+/*
+ * TA_CMD_BNXT_COPY_COREDUMP - copy the core dump into shm
+ *
+ * param[0] (in value) - value.a: offset at which data to be copied from
+ * value.b: size of the data
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ * TEE_ERROR_ITEM_NOT_FOUND - Corrupt core dump
+ */
+ TA_CMD_BNXT_COPY_COREDUMP,
+
+/*
+ * TA_CMD_BNXT_FW_UPGRADE - upgrade the bnxt firmware
+ *
+ * param[0] (in value) - value.a: size of the f/w image
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+ TA_CMD_BNXT_FW_UPGRADE,
+};
+
+/**
+ * struct tee_bnxt_fw_private - OP-TEE bnxt private data
+ * @dev: OP-TEE based bnxt device.
+ * @ctx: OP-TEE context handler.
+ * @session_id: TA session identifier.
+ */
+struct tee_bnxt_fw_private {
+ struct device *dev;

Why is the pointer back needed?
the dev pointer is used in "dev_err()"

+ struct tee_context *ctx;
+ u32 session_id;
+ struct tee_shm *fw_shm_pool;
+};
+
+static struct tee_bnxt_fw_private pvt_data;
+
+static inline void prepare_args(int cmd,
+ struct tee_ioctl_invoke_arg *inv_arg,
+ struct tee_param *param)
+{
+ memset(inv_arg, 0, sizeof(*inv_arg));
+ memset(param, 0, (MAX_TEE_PARAM_ARRY_MEMB * sizeof(*param)));
+
+ inv_arg->func = cmd;
+ inv_arg->session = pvt_data.session_id;
+ inv_arg->num_params = MAX_TEE_PARAM_ARRY_MEMB;
+
+ /* Fill invoke cmd params */
+ switch (cmd) {
+ case TA_CMD_BNXT_HEALTH_STATUS:
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+ break;
+ case TA_CMD_BNXT_HANDSHAKE:
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
+ break;
+ case TA_CMD_BNXT_COPY_COREDUMP:
+ case TA_CMD_BNXT_FW_UPGRADE:
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT;
+ param[0].u.memref.shm = pvt_data.fw_shm_pool;
+ param[0].u.memref.size = MAX_SHM_MEM_SZ;
+ param[0].u.memref.shm_offs = 0;
+ param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
+ break;
+ case TA_CMD_BNXT_FASTBOOT:
+ default:
+ /* Nothing to do */
+ break;
+ }
+}
+
+/**
+ * tee_bnxt_fw_load() - Load the bnxt firmware
+ * Uses an OP-TEE call to start a secure
+ * boot process.
+ * Returns 0 on success, negative errno otherwise.
+ */
+int tee_bnxt_fw_load(void)
+{
+ int ret = 0;
+ struct tee_ioctl_invoke_arg inv_arg;
+ struct tee_param param[MAX_TEE_PARAM_ARRY_MEMB];
+
+ if (!pvt_data.ctx)
+ return -ENODEV;
+
+ prepare_args(TA_CMD_BNXT_FASTBOOT, &inv_arg, param);
+
+ 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_BNXT_LOAD invoke err: %x\n",
+ (ret < 0) ? ret : inv_arg.ret);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(tee_bnxt_fw_load);

Why are you exporting symbols for a single file? What uses these?
These apis will be used by bnxt driver, still working on open sourcing changes


Hi Greg,

The above API is used by the bnxt_en Ethernet driver to load firmware that is stored in the secure region of DDR that can only be accessed through secure calls via TEE.

EXPORT_SYMBOL is needed given that bnxt_en driver (the client that uses this API) is usually loaded as a module.

This feels really wrong, are you sure this all is correct?

Is there anything specific that looks wrong? Please help to point out and we'll fix it.

Thanks,

Ray


I stopped reading here :)

thanks,

greg k-h