Re: [PATCH v3] memory: tegra: add multi-socket support to the memory interconnect

[Jon Hunter]

On 26/06/2026 14:14, Sumit Gupta wrote:
> Add support for representing each memory-controller instance (one
> per NUMA node / socket) as its own interconnect (ICC) provider,
> with its own MC client nodes, to match the hardware topology on
> multi-socket Tegra SoCs.
>
> Use the NUMA node ID to make client IDs globally unique across
> per-socket providers, since the ICC framework allocates node IDs
> from a single global IDR. Per-socket MC and EMC node names are
> also derived from dev_name() so they match the corresponding
> debugfs subdirectory. On single-socket platforms (NUMA_NO_NODE)
> the existing client IDs and node-name strings are preserved.
>
> Each socket's MC and EMC therefore get their own debugfs
> subdirectory under /sys/kernel/debug/{mc,emc}/. The parent
> directories are created on first probe.
>
> Bandwidth requests from MC clients in a socket are routed to
> that socket's local BPMP.
>
> Signed-off-by: Sumit Gupta <sumitg@xxxxxxxxxx>
> ---
> v2[2] -> v3:
> - Reduce per-socket shift to 12 bits to keep composed ICC node
>    IDs below ICC_DYN_ID_START.
>
> v1[1] -> v2:
> - Mutex protected lazy creation of the mc/emc debugfs parent.
> - Rename {mc|emc}_debugfs_root to tegra_{mc|emc}_debugfs_root.
>
> [1] https://lore.kernel.org/lkml/20260521140546.3023819-1-sumitg@xxxxxxxxxx/
> [2] https://lore.kernel.org/lkml/20260602132314.486066-1-sumitg@xxxxxxxxxx/
> ---
>   drivers/memory/tegra/mc.c           | 40 ++++++++++++++++-----
>   drivers/memory/tegra/mc.h           | 37 +++++++++++++++++++
>   drivers/memory/tegra/tegra186-emc.c | 55 ++++++++++++++++++++++++-----
>   3 files changed, 115 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c
> index ec80ea9cc173..51ad0d3e48d4 100644
> --- a/drivers/memory/tegra/mc.c
> +++ b/drivers/memory/tegra/mc.c
> @@ -3,6 +3,7 @@
>    * Copyright (C) 2014-2026 NVIDIA CORPORATION.  All rights reserved.
>    */
>   
> +#include <linux/cleanup.h>
>   #include <linux/clk.h>
>   #include <linux/delay.h>
>   #include <linux/dma-mapping.h>
> @@ -10,6 +11,7 @@
>   #include <linux/interrupt.h>
>   #include <linux/kernel.h>
>   #include <linux/module.h>
> +#include <linux/mutex.h>


There is a conflict here with the latest -next and so we need to rebase 
this. Otherwise ...

Tested-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Reviewed-by: Jon Hunter <jonathanh@xxxxxxxxxx>

Thanks
Jon

--
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