linux-hardening - Re: [PATCH 2/3] dma: amlogic: Add general DMA driver for SoCs

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <d8a81447-d16e-4abc-a115-5c05ab506792@amlogic.com>
Date: Fri, 19 Dec 2025 10:04:10 +0800
From: Xianwei Zhao <xianwei.zhao@...ogic.com>
To: Krzysztof Kozlowski <krzk@...nel.org>, Vinod Koul <vkoul@...nel.org>,
 Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>,
 Conor Dooley <conor+dt@...nel.org>, Kees Cook <kees@...nel.org>,
 "Gustavo A. R. Silva" <gustavoars@...nel.org>
Cc: linux-amlogic@...ts.infradead.org, dmaengine@...r.kernel.org,
 devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
 linux-hardening@...r.kernel.org
Subject: Re: [PATCH 2/3] dma: amlogic: Add general DMA driver for SoCs

Hi Krzysztof,
    Thanks for your review.

On 2025/12/16 16:46, Krzysztof Kozlowski wrote:
> [ EXTERNAL EMAIL ]
> 
> On 16/12/2025 09:03, Xianwei Zhao via B4 Relay wrote:
>> From: Xianwei Zhao <xianwei.zhao@...ogic.com>
>>
>> Amlogic SoCs include a general-purpose DMA controller that can be used
>> by multiple peripherals, such as I2C PIO and I3C. Each peripheral group
>> is associated with a dedicated DMA channel in hardware.
>>
>> Signed-off-by: Xianwei Zhao <xianwei.zhao@...ogic.com>
>> ---
>>   drivers/dma/Kconfig       |   8 +
>>   drivers/dma/Makefile      |   1 +
>>   drivers/dma/amlogic-dma.c | 567 ++++++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 576 insertions(+)
>>
>> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
>> index 8bb0a119ecd4..fc7f70e22c22 100644
>> --- a/drivers/dma/Kconfig
>> +++ b/drivers/dma/Kconfig
>> @@ -85,6 +85,14 @@ config AMCC_PPC440SPE_ADMA
>>        help
>>          Enable support for the AMCC PPC440SPe RAID engines.
>>
>> +config AMLOGIC_DMA
>> +     tristate "Amlogic genneral DMA support"
>> +     depends on ARCH_MESON
> 
> Missing compile test.
>

Will Add it. depends on ARCH_MESON || COMPILE_TEST

>> +     select DMA_ENGINE
>> +     select REGMAP_MMIO
>> +     help
>> +       Enable support for the Amlogic general DMA engines.
>> +
> 
> 
> 
>> +
>> +     ret = of_dma_controller_register(np, aml_of_dma_xlate, aml_dma);
>> +     if (ret)
>> +             return ret;
>> +
>> +     regmap_write(aml_dma->regmap, RCH_INT_MASK, 0xffffffff);
>> +     regmap_write(aml_dma->regmap, WCH_INT_MASK, 0xffffffff);
>> +
>> +     ret = devm_request_irq(&pdev->dev, aml_dma->irq, aml_dma_interrupt_handler,
>> +                            IRQF_SHARED, dev_name(&pdev->dev), aml_dma);
>> +     if (ret)
>> +             return ret;
>> +
>> +     dev_info(aml_dma->dma_device.dev, "initialized\n");
> 
> Useless message, drop. This does not look like useful printk message.
> Drivers should be silent on success:
> https://elixir.bootlin.com/linux/v6.15-rc7/source/Documentation/process/coding-style.rst#L913
> https://elixir.bootlin.com/linux/v6.15-rc7/source/Documentation/process/debugging/driver_development_debugging_guide.rst#L79
> 

Will drop it.

>> +
>> +     return 0;
>> +}
>> +
>> +static const struct of_device_id aml_dma_ids[] = {
>> +     { .compatible = "amlogic,general-dma", },
>> +     {},
>> +};
>> +MODULE_DEVICE_TABLE(of, aml_dma_ids);
>> +
>> +static struct platform_driver aml_dma_driver = {
>> +     .probe = aml_dma_probe,
>> +     .driver         = {
>> +             .name   = "aml-dma",
>> +             .of_match_table = aml_dma_ids,
>> +     },
>> +};
>> +
>> +module_platform_driver(aml_dma_driver);
>> +
>> +MODULE_DESCRIPTION("GENERAL DMA driver for Amlogic");
>> +MODULE_AUTHOR("Xianwei Zhao <xianwei.zhao@...ogic.com>");
>> +MODULE_ALIAS("platform:aml-dma");
>> +MODULE_LICENSE("GPL");
>>
> 
> 
> Best regards,
> Krzysztof