linux-kernel - [PATCH v6 0/4] Add generic driver for on-chip SRAM

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-next>] [day] [month] [year] [list]

Date:	Fri, 16 Nov 2012 11:30:13 +0100
From:	Philipp Zabel <p.zabel@...gutronix.de>
To:	linux-kernel@...r.kernel.org
Cc:	Arnd Bergmann <arnd@...db.de>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Grant Likely <grant.likely@...retlab.ca>,
	Rob Herring <rob.herring@...xeda.com>,
	Paul Gortmaker <paul.gortmaker@...driver.com>,
	Shawn Guo <shawn.guo@...aro.org>,
	Richard Zhao <richard.zhao@...escale.com>,
	Huang Shijie <shijie8@...il.com>,
	Dong Aisheng <dong.aisheng@...aro.org>,
	Matt Porter <mporter@...com>,
	Fabio Estevam <fabio.estevam@...escale.com>,
	Javier Martin <javier.martin@...ta-silicon.com>,
	kernel@...gutronix.de, devicetree-discuss@...ts.ozlabs.org
Subject: [PATCH v6 0/4] Add generic driver for on-chip SRAM

These patches add support to configure on-chip SRAM via device-tree
node or platform data and to obtain the resulting genalloc pool from
the physical address or a phandle pointing at the device tree node.
This allows drivers to allocate SRAM with the genalloc API without
hard-coding the genalloc pool pointer.

The on-chip SRAM on i.MX53 and i.MX6q can be registered via device tree
and changed to use the simple generic SRAM driver:

                ocram: ocram@...00000 {
                        compatible = "fsl,imx-ocram", "sram";
                        reg = <0x00900000 0x3f000>;
                };

A driver that needs to allocate SRAM buffers, like the video processing
unit on i.MX53, can retrieve the genalloc pool from a phandle in the
device tree using of_get_named_gen_pool(node, "iram", 0) from patch 1:

                vpu@...f4000 {
                        /* ... */
                        iram = <&ocram>;
                };

Changes since v5:
 - Addressed Paul Gortmaker's comments, merging the clock patch
   into the SRAM driver patch.
 - Hard coded the allocation granularity to 512 bytes and dropped
   Matt Porter's patch for now. Whether or not this should be
   configured in the device tree could use further discussion.
 - Added a coda driver patch to use the genalloc API and, again,
   the i.MX53/i.MX6 device tree patch to show the whole picture.

regards
Philipp

---
 Documentation/devicetree/bindings/misc/sram.txt |   17 ++++
 arch/arm/boot/dts/imx53.dtsi                    |    5 +
 arch/arm/boot/dts/imx6q.dtsi                    |    6 ++
 drivers/media/platform/Kconfig                  |    3 +-
 drivers/media/platform/coda.c                   |   47 ++++++---
 drivers/misc/Kconfig                            |    9 ++
 drivers/misc/Makefile                           |    1 +
 drivers/misc/sram.c                             |  121 +++++++++++++++++++++++
 include/linux/genalloc.h                        |   14 +++
 lib/genalloc.c                                  |   67 +++++++++++++
 10 files changed, 274 insertions(+), 16 deletions(-)

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/