Previously, dma_set_mask() on powernv was convoluted:
0) Call dma_set_mask() (a/p/kernel/dma.c)
1) In dma_set_mask(), ppc_md.dma_set_mask() exists, so call it.
2) On powernv, that function pointer is pnv_dma_set_mask().
In pnv_dma_set_mask(), the device is pci, so call pnv_pci_dma_set_mask().
3) In pnv_pci_dma_set_mask(), call pnv_phb->set_dma_mask() if it exists.
4) It only exists in the ioda case, where it points to
pnv_pci_ioda_dma_set_mask(), which is the final function.
So the call chain is:
dma_set_mask() ->
pnv_dma_set_mask() ->
pnv_pci_dma_set_mask() ->
pnv_pci_ioda_dma_set_mask()
Both ppc_md and pnv_phb function pointers are used.
Rip out the ppc_md call, pnv_dma_set_mask() and pnv_pci_dma_set_mask().
Instead:
0) Call dma_set_mask() (a/p/kernel/dma.c)
1) In dma_set_mask(), the device is pci, and pci_controller_ops.dma_set_mask()
exists, so call pci_controller_ops.dma_set_mask()
2) In the ioda case, that points to pnv_pci_ioda_dma_set_mask().
The new call chain is
dma_set_mask() ->
pnv_pci_ioda_dma_set_mask()
Now only the pci_controller_ops function pointer is used.
The fallback paths for p5ioc2 are the same.
Previously, pnv_pci_dma_set_mask() would find no pnv_phb->set_dma_mask()
function, to it would call __set_dma_mask().
Now, dma_set_mask() finds no ppc_md call or pci_controller_ops call,
so it calls __set_dma_mask().
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Remove powernv generic PCI controller operations. Replace it with
controller ops for each of the two supported PHBs.
As an added bonus, make the two new structs const, which will help
guard against bugs such as the one introduced in 65ebf4b63
("powerpc/powernv: Move controller ops from ppc_md to controller_ops")
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
All users of the old opal events notifier have been converted over to
the irq domain so remove the event notifier functions.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Whenever an interrupt is received for opal the linux kernel gets a
bitfield indicating certain events that have occurred and need handling
by the various device drivers. Currently this is handled using a
notifier interface where we call every device driver that has
registered to receive opal events.
This approach has several drawbacks. For example each driver has to do
its own checking to see if the event is relevant as well as event
masking. There is also no easy method of recording the number of times
we receive particular events.
This patch solves these issues by exposing opal events via the
standard interrupt APIs by adding a new interrupt chip and
domain. Drivers can then register for the appropriate events using
standard kernel calls such as irq_of_parse_and_map().
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This moves the PowerNV platform to use the pci_controller_ops
structure rather than ppc_md for PCI controller operations.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The secondary threads should enter deep idle states so as to gain maximum
powersavings when the entire core is offline. To do so the offline path
must be made aware of the available deepest idle state. Hence probe the
device tree for the possible idle states in powernv core code and
expose the deepest idle state through flags.
Since the device tree is probed by the cpuidle driver as well, move
the parameters required to discover the idle states into an appropriate
common place to both the driver and the powernv core code.
Another point is that fastsleep idle state may require workarounds in
the kernel to function properly. This workaround is introduced in the
subsequent patches. However neither the cpuidle driver or the hotplug
path need be bothered about this workaround.
They will be taken care of by the core powernv code.
Originally-by: Srivatsa S. Bhat <srivatsa@mit.edu>
Signed-off-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: linux-pm@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The dma_get_required_mask() function is used by some drivers to
query the platform about what DMA mask is needed to cover all of
memory. This is a bit of a strange semantic when we have to choose
between IOMMU translation or bypass, but essentially what it means
is "what DMA mask will give best performances".
Currently, our IOMMU backend always returns a 32-bit mask here, we
don't do anything special to it when we have bypass available. This
causes some drivers to choose a 32-bit mask, thus losing the ability
to use the bypass window, thinking this is more efficient. The problem
was reported from the driver of following device:
0004:03:00.0 0107: 1000:0087 (rev 05)
0004:03:00.0 Serial Attached SCSI controller: LSI Logic / Symbios \
Logic SAS2308 PCI-Express Fusion-MPT SAS-2 (rev 05)
This patch adds an override of that function in order to, instead,
return a 64-bit mask whenever a bypass window is available in order
for drivers to prefer this configuration.
Reported-by: Murali N. Iyer <mniyer@us.ibm.com>
Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Upcoming POWER8 chips support a concept called split core. This is where the
core can be split into subcores that although not full cores, are able to
appear as full cores to a guest.
The splitting & unsplitting procedure is mildly complicated, and explained at
length in the comments within the patch.
One notable detail is that when splitting or unsplitting we need to pull
offline cpus out of their offline state to do work as part of the procedure.
The interface for changing the split mode is via a sysfs file, eg:
$ echo 2 > /sys/devices/system/cpu/subcores_per_core
Currently supported values are '1', '2' and '4'. And indicate respectively that
the core should be unsplit, split in half, and split in quarters. These modes
correspond to threads_per_subcore of 8, 4 and 2.
We do not allow changing the split mode while KVM VMs are active. This is to
prevent the value changing while userspace is configuring the VM, and also to
prevent the mode being changed in such a way that existing guests are unable to
be run.
CPU hotplug fixes by Srivatsa. max_cpus fixes by Mahesh. cpuset fixes by
benh. Fix for irq race by paulus. The rest by mikey and mpe.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds the support for to create a direct iommu "bypass"
window on IODA2 bridges (such as Power8) allowing to bypass iommu
page translation completely for 64-bit DMA capable devices, thus
significantly improving DMA performances.
Additionally, this adds a hook to the struct iommu_table so that
the IOMMU API / VFIO can disable the bypass when external ownership
is requested, since in that case, the device will be used by an
environment such as userspace or a KVM guest which must not be
allowed to bypass translations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This uses the hooks provided by CONFIG_PPC_INDIRECT_PIO to
implement a set of hooks for IO port access to use the LPC
bus via OPAL calls for the first 64K of IO space
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We add a machine_shutdown hook that frees the OPAL interrupts
(so they get masked at the source and don't fire while kexec'ing)
and which triggers an IODA reset on all the PCIe host bridges
which will have the effect of blocking all DMAs and subsequent
PCIs interrupts.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds support for PCI-X and PCIe on the p5ioc2 IO hub using
OPAL. This includes allocating & setting up TCE tables and config
space access routines.
This also supports fallbacks via RTAS when OPAL is absent, using
legacy TCE format pre-allocated via the device-tree (BML style)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds a skeletton for the new Power "Non Virtualized"
platform which will be used by machines supporting running
without an hypervisor, for example in order to run KVM.
These machines will be using a new firmware called OPAL
for which the support will be provided by later patches.
The PowerNV platform is intended to be also usable under
the BML environment used internally for early CPU bringup
which is why the code also supports using RTAS instead of
OPAL in various places.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
