[PATCH 4/4] iommu/exynos: enhancements of System MMU driver with DT

'Joerg Roedel' joro at 8bytes.org
Sat Nov 17 07:49:18 EST 2012


On Wed, Nov 14, 2012 at 05:51:12PM +0900, Cho KyongHo wrote:
> This commit enhances power management of System MMU and its client
> devices with the following changes:
>  - Each System MMU device becomes the parent device of its client
>    device while probe(). Thus, exynos-iommu driver must be initialized
>    before client devices.
>  - System MMU driver does not pm_runtime_get/put() by itself and runtime
>    power gating is performed by client devices.
>  - System is safe when suspend/resume without any care by client device
>    drivers.
> 
> In addition, System MMUs can be seperate into several groups that are
> belongs to a single client device like FIMC-IS block. If such blocks are
> controlled by a single device descriptor, all System MMUs in the blocks
> must be enabled/disabled by a single device descriptor. The problem is
> that clock gating and power gating may be not the same among all System
> MMUs in the blocks. Thus, System MMUs are grouped by clock gating and
> power gating and they are chained by parent-child relationships.
> 
> exynos-iommu driver now also supports debugfs to identify the state of
> each System MMU.
> 
> The last big change is to support DT. The desription of the properties
> of DT nodes are described in the source file.
> 
> Signed-off-by: KyongHo Cho <pullip.cho at samsung.com>
> ---
>  drivers/iommu/Kconfig        |   17 +-
>  drivers/iommu/exynos-iommu.c | 1420 +++++++++++++++++++++++++++++++-----------
>  2 files changed, 1077 insertions(+), 360 deletions(-)

This patch does multiple things and is quite large. Please split it down
into reasonable chunks and resubmit.

Patches 1-3 look good to me and I do not mind taking them for 3.8.
Please let me know if you prefer these patches standalone in 3.8 or
together with this patch split up.


	Joerg





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