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

Ray Jui
2019-09-11T17:56:38Z

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@linuxfoundation.org> wrote:
>>
>> On Tue, Sep 10, 2019 at 08:47:04PM +0530, Sheetal Tigadoli wrote:
>>> From: Vikas Gupta <vikas.gupta@broadcom.com>
>>>
>>> This driver registers on TEE bus to interact with OP-TEE based
>>> BNXT firmware management modules
>>>
>>> Signed-off-by: Vikas Gupta <vikas.gupta@broadcom.com>
>>> Signed-off-by: Sheetal Tigadoli <sheetal.tigadoli@broadcom.com>
>>> ---
>>> 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