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From: Sumit Gupta <sumitg@nvidia.com>
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	<conor+dt@kernel.org>, <maz@kernel.org>, <mark.rutland@arm.com>,
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Subject: [Patch v3 0/2] memory: tegra: Skip restricted register access from Guest
Date: Fri, 12 Apr 2024 18:35:38 +0530
Message-ID: <20240412130540.28447-1-sumitg@nvidia.com>
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MC SID and Broadbast channel register access is restricted for Guest VM.
But the Tegra MC driver is considering both these regions as mandatory
and causes error on access. Change that to consider both the regions as
optional in SoC's from Tegra186 onwards. Then skip access to the
restricted registers from Guest if its region is not present in Guest DT
and hence not mapped.
Previously, the solution in [1] was not accepted. Now, handled the
problem with this alternate solution.

---
v2[2] -> v3:
- fix the yaml error.
- add null check for ch_regs in mc_ch_readl() causing error in old SoC's
- remove unused populate label reported by kernel test robot.
- fix existing compile warning about length of name in tegra186_mc_probe.

v1[1] -> v2:
- consider broadcast channel registers also as restricted along with sid
- make sid and broadcast regions optional and access if present in dt.
- update the yaml file.

Sumit Gupta (2):
  dt-bindings: make sid and broadcast reg optional
  memory: tegra: make sid and broadcast regions optional

 .../nvidia,tegra186-mc.yaml                   | 95 ++++++++++---------
 drivers/memory/tegra/mc.c                     |  9 +-
 drivers/memory/tegra/mc.h                     | 22 +++--
 drivers/memory/tegra/tegra186.c               | 25 ++---
 4 files changed, 82 insertions(+), 69 deletions(-)

[1]https://lore.kernel.org/lkml/20240206114852.8472-1-sumitg@nvidia.com/
[2]https://lore.kernel.org/lkml/20240402132626.24693-1-sumitg@nvidia.com/

-- 
2.17.1