| From: |
| Philipp Zabel <p.zabel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> |
| To: |
| linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org |
| Subject: |
| [PATCH v6 0/4] Add generic driver for on-chip SRAM |
| Date: |
| Fri, 16 Nov 2012 11:30:13 +0100 |
| Message-ID: |
| <1353061817-3207-1-git-send-email-p.zabel@pengutronix.de> |
| Cc: |
| Fabio Estevam <fabio.estevam-KZfg59tc24xl57MIdRCFDg@public.gmane.org>, Matt Porter <mporter-l0cyMroinI0@public.gmane.org>,
Dong Aisheng <dong.aisheng-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>,
Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>,
devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>,
Paul Gortmaker <paul.gortmaker-CWA4WttNNZF54TAoqtyWWQ@public.gmane.org>,
Richard Zhao <richard.zhao-KZfg59tc24xl57MIdRCFDg@public.gmane.org>,
Javier Martin <javier.martin-N4RbWZIug12MkV8/HQOAswC/G2K4zDHf@public.gmane.org>, kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org,
Huang Shijie <shijie8-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> |
| Archive‑link: | |
Article |
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@00900000 {
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@63ff4000 {
/* ... */
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(-)
