linux-kernel - Re: [PATCH v2 16/35] brcmfmac: acpi: Add support for fetching Apple ACPI properties

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: <d72bf3e4-1a49-d354-9439-5f52334d2698@broadcom.com>
Date:   Mon, 10 Jan 2022 10:11:24 +0100
From:   Arend van Spriel <arend.vanspriel@...adcom.com>
To:     Hector Martin <marcan@...can.st>,
        Kalle Valo <kvalo@...eaurora.org>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Len Brown <lenb@...nel.org>,
        Arend van Spriel <aspriel@...il.com>,
        Franky Lin <franky.lin@...adcom.com>,
        Hante Meuleman <hante.meuleman@...adcom.com>,
        Chi-hsien Lin <chi-hsien.lin@...ineon.com>,
        Wright Feng <wright.feng@...ineon.com>,
        Dmitry Osipenko <digetx@...il.com>
Cc:     Sven Peter <sven@...npeter.dev>,
        Alyssa Rosenzweig <alyssa@...enzweig.io>,
        Mark Kettenis <kettenis@...nbsd.org>,
        Rafał Miłecki <zajec5@...il.com>,
        Pieter-Paul Giesberts <pieter-paul.giesberts@...adcom.com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Hans de Goede <hdegoede@...hat.com>,
        "John W. Linville" <linville@...driver.com>,
        "brian m. carlson" <sandals@...stytoothpaste.net>,
        Andy Shevchenko <andy.shevchenko@...il.com>,
        linux-wireless@...r.kernel.org, netdev@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-acpi@...r.kernel.org, brcm80211-dev-list.pdl@...adcom.com,
        SHA-cyfmac-dev-list@...ineon.com
Subject: Re: [PATCH v2 16/35] brcmfmac: acpi: Add support for fetching Apple
 ACPI properties

On 1/4/2022 8:26 AM, Hector Martin wrote:
> On DT platforms, the module-instance and antenna-sku-info properties
> are passed in the DT. On ACPI platforms, module-instance is passed via
> the analogous Apple device property mechanism, while the antenna SKU
> info is instead obtained via an ACPI method that grabs it from
> non-volatile storage.
> 
> Add support for this, to allow proper firmware selection on Apple
> platforms.
> 
> Signed-off-by: Hector Martin <marcan@...can.st>
> ---
>   .../broadcom/brcm80211/brcmfmac/Makefile      |  2 +
>   .../broadcom/brcm80211/brcmfmac/acpi.c        | 47 +++++++++++++++++++
>   .../broadcom/brcm80211/brcmfmac/common.c      |  1 +
>   .../broadcom/brcm80211/brcmfmac/common.h      |  9 ++++
>   4 files changed, 59 insertions(+)
>   create mode 100644 drivers/net/wireless/broadcom/brcm80211/brcmfmac/acpi.c

[...]

> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/acpi.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/acpi.c
> new file mode 100644
> index 000000000000..2b1a4448b291
> --- /dev/null
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/acpi.c
> @@ -0,0 +1,47 @@
> +// SPDX-License-Identifier: ISC
> +/*
> + * Copyright The Asahi Linux Contributors
> + */
> +
> +#include <linux/acpi.h>
> +#include "debug.h"
> +#include "core.h"
> +#include "common.h"
> +
> +void brcmf_acpi_probe(struct device *dev, enum brcmf_bus_type bus_type,
> +		      struct brcmf_mp_device *settings)
> +{
> +	acpi_status status;
> +	const union acpi_object *o;
> +	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
> +	struct acpi_device *adev = ACPI_COMPANION(dev);
> +
> +	if (!adev)
> +		return;
> +
> +	if (!ACPI_FAILURE(acpi_dev_get_property(adev, "module-instance",
> +						ACPI_TYPE_STRING, &o))) {
> +		brcmf_dbg(INFO, "ACPI module-instance=%s\n", o->string.pointer);
> +		settings->board_type = devm_kasprintf(dev, GFP_KERNEL,
> +						      "apple,%s",
> +						      o->string.pointer);
> +	} else {
> +		brcmf_dbg(INFO, "No ACPI module-instance\n");

Do you need to obtain the antenna-sku when there is no module-instance?

> +	}
> +
> +	status = acpi_evaluate_object(adev->handle, "RWCV", NULL, &buf);

Can you clarify what the above does? What does the "RWCV" mean?

> +	o = buf.pointer;
> +	if (!ACPI_FAILURE(status) && o && o->type == ACPI_TYPE_BUFFER &&
> +	    o->buffer.length >= 2) {
> +		char *antenna_sku = devm_kzalloc(dev, 3, GFP_KERNEL);
> +
> +		memcpy(antenna_sku, o->buffer.pointer, 2);
> +		brcmf_dbg(INFO, "ACPI RWCV data=%*phN antenna-sku=%s\n",
> +			  (int)o->buffer.length, o->buffer.pointer,
> +			  antenna_sku);
> +
> +		settings->antenna_sku = antenna_sku;
> +	} else {
> +		brcmf_dbg(INFO, "No ACPI antenna-sku\n");
> +	}
> +}

Download attachment "smime.p7s" of type "application/pkcs7-signature" (4219 bytes)