linux-kernel - [PATCH 0/2] Use 'arm_nommu_dma_ops' to handle dma memroy if device offer consistent dma memory region

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 for Android: free password hash cracker in your pocket

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

Message-Id: <1591605038-8682-1-git-send-email-dillon.minfei@gmail.com>
Date:   Mon,  8 Jun 2020 16:30:36 +0800
From:   dillon.minfei@...il.com
To:     robh+dt@...nel.org, mcoquelin.stm32@...il.com,
        alexandre.torgue@...com, linux@...linux.org.uk,
        vladimir.murzin@....com, kstewart@...uxfoundation.org,
        allison@...utok.net, info@...ux.net, tglx@...utronix.de
Cc:     devicetree@...r.kernel.org,
        linux-stm32@...md-mailman.stormreply.com,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        dillon min <dillon.minfei@...il.com>
Subject: [PATCH 0/2] Use 'arm_nommu_dma_ops' to handle dma memroy if device offer consistent dma memory region

From: dillon min <dillon.minfei@...il.com>

when do mmap on /dev/fb0, we will get -6 error on cortex-m3/m4 or armv7m
platform without cache support, this is caused by following reason:

on armv7m platform, if no cache support, we will use dma direct mapping,
but, this is not support on !MMU hardware, just return '-ENXIO' error

so, add use_reserved_mem() for these armv7m hardware but no-cache support.
eg, stm32f429/stm32f469.

verified on stm32f469-disco board, mmap frambuffer to userspace.

dillon min (2):
  ARM: dts: stm32: Setup 4M bytes reserved memory for mmap
  arm-nommu: Add use_reserved_mem() to check if device support reserved
    memory

 arch/arm/boot/dts/stm32f469-disco.dts | 14 ++++++++++++++
 arch/arm/mm/dma-mapping-nommu.c       | 28 +++++++++++++++++++++++++++-
 2 files changed, 41 insertions(+), 1 deletion(-)

-- 
2.7.4