linux-kernel - Re: [PATCH 3/4] iommu: dart: Write to all DART_T8020_STREAM

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]

Date:   Sat, 28 Jan 2023 20:45:37 +0900
From:   Hector Martin <marcan@...can.st>
To:     Sven Peter <sven@...npeter.dev>, Joerg Roedel <joro@...tes.org>,
        Will Deacon <will@...nel.org>,
        Robin Murphy <robin.murphy@....com>
Cc:     Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Alyssa Rosenzweig <alyssa@...enzweig.io>,
        linux-arm-kernel@...ts.infradead.org, asahi@...ts.linux.dev,
        iommu@...ts.linux.dev, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/4] iommu: dart: Write to all DART_T8020_STREAM_SELECT

On 28/01/2023 20.11, Sven Peter wrote:
> We're about to add support for a DART variant that use more than 16
> streams and requires writing to two separate stream select registers
> when issuing TLB flushes.
> 
> Signed-off-by: Sven Peter <sven@...npeter.dev>
> ---
>  drivers/iommu/apple-dart.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
> index 7d8b2b90cdb6..7579c97a9062 100644
> --- a/drivers/iommu/apple-dart.c
> +++ b/drivers/iommu/apple-dart.c
> @@ -372,12 +372,14 @@ apple_dart_t8020_hw_stream_command(struct apple_dart_stream_map *stream_map,
>  			     u32 command)
>  {
>  	unsigned long flags;
> -	int ret;
> +	int ret, i;
>  	u32 command_reg;
>  
>  	spin_lock_irqsave(&stream_map->dart->lock, flags);
>  
> -	writel(stream_map->sidmap[0], stream_map->dart->regs + DART_T8020_STREAM_SELECT);
> +	for (i = 0; i < BITS_TO_U32(stream_map->dart->num_streams); i++)
> +		writel(stream_map->sidmap[i],
> +		       stream_map->dart->regs + DART_T8020_STREAM_SELECT + 4 * i);
>  	writel(command, stream_map->dart->regs + DART_T8020_STREAM_COMMAND);
>  
>  	ret = readl_poll_timeout_atomic(

Acked-by: Hector Martin <marcan@...can.st>

- Hector