[PATCH v13 00/19] iommu/exynos: Fixes and Enhancements of System MMU driver with DT

From: Shaik Ameer Basha
Date: Mon May 12 2014 - 02:16:27 EST


This is the subset of previous v12 series and includes only the fixes and
enhancements, leaving out the private DT bindings as discussed in the below thread.
-- http://www.gossamer-threads.com/lists/linux/kernel/1918178

This patch series includes,
1] fixes for exynos-iommu driver build break
2] includes several bug fixes and enhancements for the exynos-iommu driver
3] code to handle multiple exynos sysmmu versions
4] adding support for device tree
Documentation/devicetree/bindings/iommu/samsung,sysmmu.txt

Change log:
v13:
- Rebased to the latest 3.15-rc4 master branch
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master (3.15-rc4)
- This patch series is the subset of the previous patch series
v12: iommu/exynos: Fixes and Enhancements of System MMU driver with dt
Changes incude:
- Removed dt bindings and code specific to "mmu-masters" property
- Dropped patch 18/31 from previous patch series as suggested by 'Tomasz Figa'.
- Fixes buid break issue in patch 01/19 by merging the following patches
from the previous series
iommu/exynos: do not include removed header
iommu/exynos: fix address handling
iommu/exynos: handle one instance of sysmmu with a device descriptor
- Shuffled the patches to bring all the fixes and enhancement to the start
of the patch series

v12:
- Rebased to the latest 3.15-rc2 master branch
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master (3.15-rc2)
- Addressed v11 review comments from
'Sachin Kamat', 'Tomasz Figa' and 'Shaik Ameer Basha'
- Uses macro names instead of magic numbers for clock description in DT
- Moved DT binding document to seperate patch
- dtsi changes are separated into multiple patches
- patch description of some patches are updated according to the review comments
- removed the macros which hides the clock operations
- review comments related to compatible strings will be fixed in followup patches

v11:
- Rebased on the latest works on clock, arm/samsung, iommu branches
- Change the property to link System MMU and its master H/W
'iommu' in the master's node -> 'mmu-masters' in the System MMU's node
- Changed compatible string:
"samsung,sysmmu-v1"
"samsung,sysmmu-v2"
"samsung,sysmmu-v3.1"
"samsung,sysmmu-v3.2"
"samsung,sysmmu-v3.3"
- Change the implementation of retrieving System MMU version -> simpler
- Check NULL pointer before call to clk_enable() and clk_disable()
- Allow a single master to link to multiple System MMUs.
(fimc-is, fimd/g2d/Scaler in Exynos5420)
- Workarounds of known problems of System MMU
- Code enhancements:
* Compilable for 64-bit
* Enhanced error messages

v10:
- Rebased on the following branches
git.linaro.org/git-ro/people/mturquette/linux.git/clk-next
git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung.git/for-next
git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git/next
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master (3.12-rc3)
- Set parent clock to all System MMU clocks.
- Add clock and DT descriptos for Exynos5420
- Modified error handling in exynos_iommu_init()
- Split "iommu/exynos: support for device tree" patch into the following 6 patches
iommu/exynos: handle only one instance of System MMU
iommu/exynos: always enable runtime PM
iommu/exynos: always use a single clock descriptor
iommu/exynos: remove dbgname from drvdata of a System MMU
iommu/exynos: use managed driver helper functions
iommu/exynos: support for device tree
- Remove 'interrupt-names' and 'status' properties from DT
- Change n:1 relationship between master:System MMU into 1:1 relationship.
- Removed custom fault handler and print the status of System MMU
whenever System MMU fault is occurred.
- Post Antonios Motakis's commit together:
"iommu/exynos: add devices attached to the System MMU to an IOMMU group"

v9:
- Rebased on the following branches
git.linaro.org/git-ro/people/mturquette/linux.git/clk-next
git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung.git/samsung-next
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master (3.11-rc4)
- Split "add bus notifier for registering System MMU" into 5 patches
- Call clk_prepare() that was missing in v8.
- Fixed base address of sysmmu_tv in exynos4210.dtsi
- BUG_ON() instead of return -EADDRINUSE when trying mapping on an mapped area
- Moved camif_top to 317 in drivers/clk/samsung/clk-exynos5250.c
- Removed 'iommu' property from 'codec'(mfc) node
- Does not make 'master' clock to be the parent of 'sysmmu' clock.
'master' clock is enabled before accessing control registers of System MMU
and disabled after the access.

v8:
- Reordered patch list: moved "change rwloc to spinlock" to the last.
- Fixed remained bug in "fix page table maintenance".
- Always return 0 from exynos_iommu_attach_device().
- Removed prefetch buffer setting when System MMU is enabled
due to the restriction of prefetch buffers:
A prefetch buffer must not hit from more than one DMA.
For instance with GScalers, if a single prefetch buffer is initialized
with 0x0 ~ 0xFFFFFFFF and a GScaler works on source buffer at 0x10000000
and target buffer @ 0x20000000, the System MMU may be got deadlock.
Clients must initialize prefetch buffers with custom function defined
in exynos-iommu drivers whenever they need to enable prefetch buffers.
- The clock of System MMU has no relationship with the clock of its master H/W.
The clock of master H/W is always enabled when exynos-iommu driver needs to
access MMIO area and disabled as soon as the access finishes.
- Removed err_page variable used in exynos_iommu_unmap() in the previous patch
"fix page table maintenance".
- Split a big patch "add bus notifier for registering System MMU".
Extracted the following 2 patches: 9/12 and 10/12.
- And some additional fixes...

v7:
- Rebased on the stable 3.10
- Registered PM domains and gate clocks with DT
- Changed connection method between a System MMU and its master H/W
'mmu-master' property in the node of System MMU
--> 'iommu' property in the node of master H/W
- Marking device descriptor of master H/W of a System MMU with bus notifier.
- Power management (PM_RUNTIME, PM_SLEEP) of System MMUs with gpd_dev_ops
of Generic IO Powerdomain. gpd_dev_ops are set to the master H/Ws
before they are probed in the bus notifier.
- Removed additional debugging features like debugfs entries and
version names.
- Removed support for advanced features of System MMU 3.2 and 3.3
the current IOMMU API cannot handle the feature
(A kind of L2 TLB that fetches several consequence page table entries.
It must be initialized by the driver of master H/W whenever it works.)

v6:
- Rebased on the branch, next/iommu-exynos of
git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung.git

v5:
- new bugfix: patch 01
- Reordered patches
* patch 01 ~ 05: Bugfix and enhancements of the existing driver
* patch 06 ~ 10: Device Tree support and callbacks for power management
* patch 11 : System MMU 3.2 and 3.3 support
* patch 12 ~ 14: Debugging features
- Additional code compaction

v4:
- Remove Change-Id from v3 patches
- Change the order of the third and the first patch
Thanks to Kukjin Kim.
- Fix memory leak when allocating and assigning exynos_iommu_owner to client
device if the client device has multiple System MMUs.
Thanks to Rahul Sharma.

v3:
- Fix prefetch buffer flag definition for System MMU 3.3 (patch 10/12)
- Fix incorrect setting for SET_RUNTIME_PM_OPS (patch 09/12)
Thanks to Prathyush.

v2:
- Split the patch to iommu/exynos into 9 patches
- Support for System MMU 3.3
- Some code compaction
*** BLURB HERE ***

Antonios Motakis (1):
iommu/exynos: add devices attached to the System MMU to an IOMMU
group

Cho KyongHo (18):
iommu/exynos: fix build errors
iommu/exynos: change error handling when page table update is failed
iommu/exynos: allocate lv2 page table from own slab
iommu/exynos: fix L2TLB invalidation
iommu/exynos: remove prefetch buffer setting
iommu/exynos: add missing cache flush for removed page table entries
iommu/exynos: always enable runtime PM
iommu/exynos: remove dbgname from drvdata of a System MMU
iommu/exynos: use managed device helper functions
iommu/exynos: gating clocks of master H/W
iommu/exynos: remove custom fault handler
iommu/exynos: change rwlock to spinlock
iommu/exynos: use exynos-iommu specific typedef
iommu/exynos: enhanced error messages
documentation: iommu: add binding document of Exynos System MMU
iommu/exynos: support for device tree
iommu/exynos: turn on useful configuration options
iommu/exynos: apply workaround of caching fault page table entries

.../devicetree/bindings/iommu/samsung,sysmmu.txt | 65 ++
drivers/iommu/exynos-iommu.c | 1035 ++++++++++++--------
2 files changed, 677 insertions(+), 423 deletions(-)
create mode 100644 Documentation/devicetree/bindings/iommu/samsung,sysmmu.txt

--
1.7.9.5

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