There are some IPs, such as video encoder/decoder, contains 2 slave iommus,
one for reading and the other for writing. They share the same irq and
clock with master.
This patch reconstructs to support this case by making them share the same
Page Directory, Page Tables and even the register operations.
That means every instruction to the reading MMU registers would be
duplicated to the writing MMU and vice versa.
Signed-off-by: ZhengShunQian <zhengsq@rock-chips.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Currently the driver emits a log line every time a device
attaches or detaches - which happens at every unblank/blank
of the drm for example. The message itself also has no real
value to the average user and is merely useful when
debugging a problem, so make it a dev_dbg instead.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
To flush created mappings, current mapping code relies on the fact that
during unmap the driver zaps every IOVA being unmapped and that it is
enough to zap a single IOVA of page table to remove the entire page
table from IOMMU cache. Based on these assumptions the driver was made to
simply zap the first IOVA of the mapping being created. This is enough
to invalidate first page table, which could be shared with another
mapping (and thus could be already present in IOMMU cache), but
unfortunately it does not do anything about the last page table that
could be shared with other mappings as well.
Moreover, the flushing is performed before page table contents are
actually modified, so there is a race between the CPU updating the page
tables and hardware that could be possibly running at the same time and
triggering IOMMU look-ups, which could bring back the page tables back
to the cache.
To fix both issues, this patch makes the mapping code zap first and last
(if they are different) IOVAs of new mapping after the page table is
updated.
Signed-off-by: Tomasz Figa <tfiga@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The rockchip iommu driver references its of_device_id table
from the init function, which fails to build when the table
is undefined:
iommu/rockchip-iommu.c: In function 'rk_iommu_init':
iommu/rockchip-iommu.c:1029:35: error: 'rk_iommu_dt_ids' undeclared (first use in this function)
np = of_find_matching_node(NULL, rk_iommu_dt_ids);
This removes the #ifdef and the corresponding of_match_ptr wrapper
to make it build both with CONFIG_OF enabled or disabled.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 425061b0f5 ("iommu/rockchip: Play nice in multi-platform builds")
Reviewed-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Implement domain_alloc and domain_free iommu-ops as a
replacement for domain_init/domain_destroy.
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The Rockchip IOMMU driver unconditionally executes code and registers a
struct iommu_ops with the platform bus irrespective of whether it runs
on a Rockchip SoC or not. This causes problems in multi-platform kernels
where drivers for other SoCs will no longer be able to register their
own struct iommu_ops or even try to use a struct iommu_ops for an IOMMU
that obviously isn't there.
The smallest fix I could think of is to check for the existence of any
Rockchip IOMMU devices in the device tree and skip initialization
otherwise.
This fixes a problem on Tegra20 where the DRM driver will try to use the
obviously non-existent Rockchip IOMMU.
Reported-by: Nicolas Chauvet <kwizart@gmail.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This platform_driver does not need to set an owner, it will be populated by the
driver core.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The rk3288 has several iommus. Each iommu belongs to a single master
device. There is one device (ISP) that has two slave iommus, but that
case is not yet supported by this driver.
At subsys init, the iommu driver registers itself as the iommu driver for
the platform bus. The master devices find their slave iommus using the
"iommus" field in their devicetree description. Since each slave iommu
belongs to exactly one master, their is no additional data needed at probe
to associate a slave with its master.
An iommu device's power domain, clock and irq are all shared with its
master device, and the master device must be careful to attach from the
iommu only after powering and clocking it (and leave it powered and
clocked before detaching). Because their is no guarantee what the status
of the iommu is at probe, and since the driver does not even know if the
device is powered, we delay requesting its irq until the master device
attaches, at which point we have a guarantee that the device is powered
and clocked and we can reset it and disable its interrupt mask.
An iommu_domain describes a virtual iova address space. Each iommu_domain
has a corresponding page table that lists the mappings from iova to
physical address.
For the rk3288 iommu, the page table has two levels:
The Level 1 "directory_table" has 1024 4-byte dte entries.
Each dte points to a level 2 "page_table".
Each level 2 page_table has 1024 4-byte pte entries.
Each pte points to a 4 KiB page of memory.
An iommu_domain is created when a dma_iommu_mapping is created via
arm_iommu_create_mapping. Master devices can then attach themselves to
this mapping (or attach the mapping to themselves?) by calling
arm_iommu_attach_device(). This in turn instructs the iommu driver to
write the page table's physical address into the slave iommu's "Directory
Table Entry" (DTE) register.
In fact multiple master devices, each with their own slave iommu device,
can all attach to the same mapping. The iommus for these devices will
share the same iommu_domain and therefore point to the same page table.
Thus, the iommu domain maintains a list of iommu devices which are
attached. This driver relies on the iommu core to ensure that all devices
have detached before destroying a domain.
v6: - add .add/remove_device() callbacks.
- parse platform_device device tree nodes for "iommus" property
- store platform device pointer as group iommudata
- Check for existence of iommu group instead of relying on a
dev_get_drvdata() to return NULL for a NULL device.
v7: - fixup some strings.
- In rk_iommu_disable_paging() # and % were reversed.
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Simon Xue <xxm@rock-chips.com>
Reviewed-by: Grant Grundler <grundler@chromium.org>
Reviewed-by: Stéphane Marchesin <marcheu@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
ZhengShunQian