| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <9fd66ca4-36f2-e6c2-fdb3-76e00e1e954b@quicinc.com>
Date: Thu, 27 Jul 2023 18:56:34 +0530
From: Mukesh Ojha <quic_mojha@...cinc.com>
To: Komal Bajaj <quic_kbajaj@...cinc.com>, <agross@...nel.org>,
<andersson@...nel.org>, <konrad.dybcio@...aro.org>,
<robh+dt@...nel.org>, <krzysztof.kozlowski+dt@...aro.org>,
<conor+dt@...nel.org>, <srinivas.kandagatla@...aro.org>
CC: <linux-arm-msm@...r.kernel.org>, <devicetree@...r.kernel.org>,
<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v5 2/2] nvmem: sec-qfprom: Add Qualcomm secure QFPROM
support
On 7/27/2023 12:09 PM, Mukesh Ojha wrote:
> Hi,
>
> Some questions, may not need to be addressed if the reason is
> known
>
> On 7/24/2023 2:08 PM, Komal Bajaj wrote:
>> For some of the Qualcomm SoC's, it is possible that
>> some of the fuse regions or entire qfprom region is
>> protected from non-secure access. In such situations,
>> Linux will have to use secure calls to read the region.
>> With that motivation, add secure qfprom driver.
>>
>> Signed-off-by: Komal Bajaj <quic_kbajaj@...cinc.com>
>> ---
>> drivers/nvmem/Kconfig | 13 +++++
>> drivers/nvmem/Makefile | 2 +
>> drivers/nvmem/sec-qfprom.c | 101 +++++++++++++++++++++++++++++++++++++
>> 3 files changed, 116 insertions(+)
>> create mode 100644 drivers/nvmem/sec-qfprom.c
>>
>> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
>> index b291b27048c7..764fc5feb26c 100644
>> --- a/drivers/nvmem/Kconfig
>> +++ b/drivers/nvmem/Kconfig
>> @@ -216,6 +216,19 @@ config NVMEM_QCOM_QFPROM
>> This driver can also be built as a module. If so, the module
>> will be called nvmem_qfprom.
>>
>> +config NVMEM_QCOM_SEC_QFPROM
>> + tristate "QCOM SECURE QFPROM Support"
>> + depends on ARCH_QCOM || COMPILE_TEST
>> + depends on HAS_IOMEM
>> + depends on OF
>> + select QCOM_SCM
>> + help
>> + Say y here to enable secure QFPROM support. The secure
>> QFPROM provides access
>> + functions for QFPROM data to rest of the drivers via nvmem
>> interface.
>> +
>> + This driver can also be built as a module. If so, the
>> module will be called
>> + nvmem_sec_qfprom.
>> +
>> config NVMEM_RAVE_SP_EEPROM
>> tristate "Rave SP EEPROM Support"
>> depends on RAVE_SP_CORE
>> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
>> index f82431ec8aef..e248d3daadf3 100644
>> --- a/drivers/nvmem/Makefile
>> +++ b/drivers/nvmem/Makefile
>> @@ -44,6 +44,8 @@ obj-$(CONFIG_NVMEM_NINTENDO_OTP) +=
>> nvmem-nintendo-otp.o
>> nvmem-nintendo-otp-y := nintendo-otp.o
>> obj-$(CONFIG_NVMEM_QCOM_QFPROM) += nvmem_qfprom.o
>> nvmem_qfprom-y := qfprom.o
>> +obj-$(CONFIG_NVMEM_QCOM_SEC_QFPROM) += nvmem_sec_qfprom.o
>> +nvmem_sec_qfprom-y := sec-qfprom.o
>
> Are we just doing this for just renaming the object ?
>
>> obj-$(CONFIG_NVMEM_RAVE_SP_EEPROM) += nvmem-rave-sp-eeprom.o
>> nvmem-rave-sp-eeprom-y := rave-sp-eeprom.o
>> obj-$(CONFIG_NVMEM_RMEM) += nvmem-rmem.o
>> diff --git a/drivers/nvmem/sec-qfprom.c b/drivers/nvmem/sec-qfprom.c
>> new file mode 100644
>> index 000000000000..bc68053b7d94
>> --- /dev/null
>> +++ b/drivers/nvmem/sec-qfprom.c
>> @@ -0,0 +1,101 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (c) 2023, Qualcomm Innovation Center, Inc. All rights
>> reserved.
>> + */
>> +
>> +#include <linux/firmware/qcom/qcom_scm.h>
>> +#include <linux/mod_devicetable.h>
>> +#include <linux/nvmem-provider.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/pm_runtime.h>
>> +
>> +/**
>> + * struct sec_qfprom - structure holding secure qfprom attributes
>> + *
>> + * @base: starting physical address for secure qfprom corrected
>> address space.
>> + * @dev: qfprom device structure.
>> + */
>> +struct sec_qfprom {
>> + phys_addr_t base;
>> + struct device *dev;
>> +};
>> +
>> +static int sec_qfprom_reg_read(void *context, unsigned int reg, void
>> *_val, size_t bytes)
>> +{
>> + struct sec_qfprom *priv = context;
>> + unsigned int i;
>> + u8 *val = _val;
>> + u32 read_val;
>> + u8 *tmp;
>> +
>> + for (i = 0; i < bytes; i++, reg++) {
>> + if (i == 0 || reg % 4 == 0) {
>> + if (qcom_scm_io_readl(priv->base + (reg & ~3), &read_val)) {
>> + dev_err(priv->dev, "Couldn't access fuse register\n");
>> + return -EINVAL;
>> + }
>> + tmp = (u8 *)&read_val;
>> + }
>> +
>> + val[i] = tmp[reg & 3];
>> + }
>
> Getting secure read from fuse region is fine here, since we have to read
> 4 byte from trustzone, but this restriction of reading is also there
> for sm8{4|5}50 soc's where byte by byte reading is protected and
> granularity set to 4 byte (qfprom_reg_read() in drivers/nvmem/qfprom.c)
> is will result in abort, in that case this function need to export this
> logic.
>
>> +
>> + return 0;
>> +}
>> +
>> +static int sec_qfprom_probe(struct platform_device *pdev)
>> +{
>> + struct nvmem_config econfig = {
>> + .name = "sec-qfprom",
>> + .stride = 1,
>> + .word_size = 1,
>> + .id = NVMEM_DEVID_AUTO,
>> + .reg_read = sec_qfprom_reg_read,
>> + };
>> + struct device *dev = &pdev->dev;
>> + struct nvmem_device *nvmem;
>> + struct sec_qfprom *priv;
>> + struct resource *res;
>> + int ret;
>> +
>> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>> + if (!priv)
>> + return -ENOMEM;
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + if (!res)
>> + return -EINVAL;
>> +
>> + priv->base = res->start;
>> +
>> + econfig.size = resource_size(res);
>> + econfig.dev = dev;
>> + econfig.priv = priv;
>> +
>> + priv->dev = dev;
>> +
>> + ret = devm_pm_runtime_enable(dev);
>> + if (ret)
>> + return ret;
>> +
>> + nvmem = devm_nvmem_register(dev, &econfig);
>> +
>> + return PTR_ERR_OR_ZERO(nvmem);
>> +}
>> +
>> +static const struct of_device_id sec_qfprom_of_match[] = {
>> + { .compatible = "qcom,sec-qfprom" },
>> + {/* sentinel */},
>> +};
>> +MODULE_DEVICE_TABLE(of, sec_qfprom_of_match);
>> +
>> +static struct platform_driver qfprom_driver = {
>> + .probe = sec_qfprom_probe,
>
> Why don't we have remove/remove_new callbacks?
> Same comment apply for drivers/nvmem/qfprom.c
Ignore this comment; Something new learnt with devm_* api
implementation.
-Mukesh
>
>> + .driver = {
>> + .name = "qcom_sec_qfprom",
>> + .of_match_table = sec_qfprom_of_match,
>> + },
>> +};
>> +module_platform_driver(qfprom_driver);
>> +MODULE_DESCRIPTION("Qualcomm Secure QFPROM driver");
>> +MODULE_LICENSE("GPL");
>> --
>> 2.40.1
>>
>
> -Mukesh
Powered by blists - more mailing lists