[PATCH 0/6] omap: iommu: hwmod support and code reorganization
Cousson, Benoit
b-cousson at ti.com
Sat Nov 6 14:56:41 EDT 2010
On 11/5/2010 9:19 PM, Ramirez Luna, Omar wrote:
> Boot tested on omap 3430 and 3630, functionality on iva2 only.
>
> Introduced hwmod data and support for omap3 (iva2 mmu& isp mmu) and
> omap4 (ducati mmu& tesla mmu).
>
> Minor cleanup due to this changes.
>
> There is an issue (present without patches too):
>
> Doing a cycle of insmod-rmmod to iommu module and then full
> insmod of bridgedriver (with all dependencies) causes the next
> read of iommu registers to dump an unhandled fault log; this,
> because when rmmod of iommu is called it tries to clean the
> iommu tables and flush any old entry prior to removing the driver,
> however these reads/writes are attempted while the MMU is under
> reset and will timeout on the L3 IVA target agent, which will leave
> MMU unusable until the proper restore sequence to clear this L3
> error is executed.
>
> Fix would be to move page table allocation to iommu get and its
> correspondent free to iommu put, however it will fall entirely
> under iommu user responsibility, as it needs to clear the mmu
> reset bit, before calling iommu functions that read/write into
> mmu registers (which should apply only for first boot or on
> baseimage reload); trading this restriction in order to keep
> the same generic iommu code for all omap iommu devices.
>
> This issue has been seen on omap3 iva2 mmu, same restriction should
> apply for tesla mmu.
>
> For discussion: should iommu handle mmu reset source directly?
> This register is grouped into an IVA PRM register which handles
> sequencer, iva2 mmu and dsp resets. As mentioned iommu handles
> cam, iva2 mmu (OMAP3) and tesla, ducati mmu (OMAP4), only tesla
> and iva2 should suffer from this restriction and according changes
> should be needed to handle both cases on mach-omap2 code. This
> also affects hwmod, since, if defined, it tries to read SYSC
> registers at boot time when registering the hwmod and causing the
> same issue.
>
> Omar Ramirez Luna (6):
> omap: iommu: remove redundant clock usage
> OMAP3: hwmod data: Add mmu for iva2 and isp
> OMAP4: hwmod data: add mmu hwmod for ducati and tesla
> omap: iommu: intial hwmod support
> omap: iommu: hwmod device enable/disable routines
> omap: iommu: code reorganization and cleanup
Could you please try to use a consistent naming in the subjects?
OMAP3, OMAP4, OMAP2 --> OMAP and not omap.
Thanks,
Benoit
>
> arch/arm/mach-omap2/omap-iommu.c | 168 +++++++++-------------------
> arch/arm/mach-omap2/omap_hwmod_3xxx_data.c | 103 +++++++++++++++++
> arch/arm/mach-omap2/omap_hwmod_44xx_data.c | 105 +++++++++++++++++
> arch/arm/plat-omap/include/plat/iommu.h | 19 +++-
> arch/arm/plat-omap/include/plat/omap34xx.h | 2 +
> arch/arm/plat-omap/iommu.c | 64 ++++-------
> 6 files changed, 299 insertions(+), 162 deletions(-)
>
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