Commit Graph

14 Commits

Author SHA1 Message Date
hotran aca314efb1 mailbox: pcc: Support HW-Reduced Communication Subspace type 2
ACPI 6.1 has a PCC HW-Reduced Communication Subspace type 2 intended for
use on HW-Reduce ACPI Platform, which requires read-modify-write sequence
to acknowledge doorbell interrupt. This patch provides the implementation
for the Communication Subspace Type 2.

Signed-off-by: Hoan Tran <hotran@apm.com>
Reviewed-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 00:37:20 +02:00
Rafael J. Wysocki fa81e66ec8 Merge branches 'pm-cpufreq', 'pm-cpuidle' and 'acpi-cppc'
* pm-cpufreq:
  cpufreq: dt: Drop stale comment
  cpufreq: intel_pstate: Documenation for structures
  cpufreq: intel_pstate: fix inconsistency in setting policy limits
  intel_pstate: Avoid extra invocation of intel_pstate_sample()
  intel_pstate: Do not set utilization update hook too early

* pm-cpuidle:
  intel_idle: Add KBL support
  intel_idle: Add SKX support
  intel_idle: Clean up all registered devices on exit.
  intel_idle: Propagate hot plug errors.
  intel_idle: Don't overreact to a cpuidle registration failure.
  intel_idle: Setup the timer broadcast only on successful driver load.
  intel_idle: Avoid a double free of the per-CPU data.
  intel_idle: Fix dangling registration on error path.
  intel_idle: Fix deallocation order on the driver exit path.
  intel_idle: Remove redundant initialization calls.
  intel_idle: Fix a helper function's return value.
  intel_idle: remove useless return from void function.

* acpi-cppc:
  mailbox: pcc: Don't access an unmapped memory address space
2016-04-08 21:46:05 +02:00
Shanker Donthineni 169b38373f mailbox: pcc: Don't access an unmapped memory address space
The acpi_pcc_probe() may end up accessing memory outside of the PCCT
table space causing the kernel panic(). Increment the pcct_entry
pointer after parsing 'HW-reduced Communications Subspace' to fix
the problem. This change also enables the parsing of subtable at
index 0.

Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Acked-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-07 01:25:28 +02:00
Rafael J. Wysocki 6a8ccb1dfd Merge branches 'acpi-processor' and 'acpi-cppc'
* acpi-processor:
  ACPI / sleep: move acpi_processor_sleep to sleep.c
  ACPI / processor : add support for ACPI0010 processor container
  ACPI / processor_idle: replace PREFIX with pr_fmt

* acpi-cppc:
  ACPI / CPPC: use MRTT/MPAR to decide if/when a req can be sent
  ACPI / CPPC: replace writeX/readX to PCC with relaxed version
  mailbox: pcc: optimized pcc_send_data
  ACPI / CPPC: optimized cpc_read and cpc_write
  ACPI / CPPC: Optimize PCC Read Write operations
2016-03-14 14:20:33 +01:00
Prakash, Prashanth 8b0f578898 mailbox: pcc: optimized pcc_send_data
pcc_send_data() can be invoked during the execution of performance
critical code as in cppc_cpufreq driver. With acpi_* APIs, the
doorbell register accessed in pcc_send_data() if present in system
memory will be searched (in cached virt to phys addr mapping),
mapped, read/written and then unmapped. These operations take
significant amount of time.

This patch maps the performance critical doorbell register
during init and then reads/writes to it directly using the
mapped virtual address. This patch + similar changes to CPPC
acpi driver reduce the time per freq. transition from around
200us to about 20us for the CPPC cpufreq driver

Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Acked-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09 23:35:29 +01:00
Alexey Klimov e9c8dc8ba9 mailbox: pcc: fix channel calculation in get_pcc_channel()
This patch fixes the calculation of pcc_chan for non-zero id.
After the compiler ignores the (unsigned long) cast the
pcc_mbox_channels pointer is type-cast and then the type-cast
offset is added which results in address outside of the range
leading to the kernel crashing.

We might add braces and make it:

pcc_chan = (struct mbox_chan *)
		((unsigned long) pcc_mbox_channels +
		(id * sizeof(*pcc_chan)));

but let's go with array approach here and use id as index.

Tested on Juno board.

Signed-off-by: Alexey Klimov <alexey.klimov@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
2016-02-02 16:39:13 +05:30
Sudip Mukherjee d311a28a58 PCC: fix dereference of ERR_PTR
get_pcc_channel() does not return NULL on error it returns the error code
in ERR_PTR, but we have been checking it for NULL.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
2015-10-16 10:46:07 +05:30
Ashwin Chaugule d3c68f218f PCC: Initialize PCC Mailbox earlier at boot
This change initializes the PCC Mailbox earlier than
the ACPI processor driver. This enables drivers introduced
in follow up patches (e.g. CPPC) to be probed via the ACPI
processor driver interface. The CPPC probe requires the PCC
channel to be initialized for it to query each CPUs performance
capabilities.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Reviewed-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-08-25 03:25:46 +02:00
Andrew Bresticker 05ae797566 mailbox: Make mbox_chan_ops const
The mailbox controller's channel ops ought to be read-only.  Update
all the mailbox drivers to make their mbox_chan_ops const as well.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Cc: Ley Foon Tan <lftan@altera.com>
Acked-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
2015-05-12 09:18:16 +05:30
Ashwin Chaugule 33350e6b18 Mailbox: Restructure and simplify PCC mailbox code
Previously the PCC driver depended on the client
side to map the communication space base address. This region
was was then used in the PCC driver and the client side.
The client side used this region to read and write its data
and the PCC driver used it to only write the PCC command.
Removing this split simplifies the PCC driver a lot. This patch
moves all communication region read/writes to the client side.
The PCC clients can now drive the PCC mailbox controller via the
mbox_client_txdone() method.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
2015-03-04 21:04:22 +05:30
Linus Torvalds bfe9183fdc Merge branch 'mailbox-devel' of git://git.linaro.org/landing-teams/working/fujitsu/integration
Pull mailbox framework updates from Jassi Brar.

* 'mailbox-devel' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
  mailbox: Add Altera mailbox driver
  mailbox: check for bit set before polling
  Mailbox: Fix return value check in pcc_init()
2015-02-11 12:56:40 -08:00
Wei Yongjun 356d5d28f2 Mailbox: Fix return value check in pcc_init()
In case of error, the function platform_create_bundle() returns
ERR_PTR() and never returns NULL. The NULL test in the return value
check should be replaced with IS_ERR().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
2015-02-06 10:57:56 +05:30
Rafael J. Wysocki efd756daf4 ACPI / PCC: Use pr_debug() for debug messages in pcc_init()
pcc_init() uses pr_err() to print two messages that are really debug
and not interesting to users.  Replace those pr_err() with pr_debug().

Reported-by: Cristian <caravena@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-05 00:40:08 +01:00
Ashwin Chaugule 86c22f8c9a Mailbox: Add support for Platform Communication Channel
ACPI 5.0+ spec defines a generic mode of communication
between the OS and a platform such as the BMC. This medium
(PCC) is typically used by CPPC (ACPI CPU Performance management),
RAS (ACPI reliability protocol) and MPST (ACPI Memory power
states).

This patch adds PCC support as a Mailbox Controller. As of
ACPI v5.1 there is no provision for clients to lookup mailbox
controllers in a way that Linux expects. e.g. in DT the clients
can list the mailboxes they can associate with in the DT binding
and then provide a unique index to lookup a channel within a mailbox.
Since the ACPI spec doesn't have anything similar, we introduce a
mailbox controller specific API so that when the client calls it,
we know to lookup in the context of a specific controller. This
also helps in keeping a consistent interface across DT and ACPI
for such drivers.

This patch implements basic PCC support using the ACPI v5.1
structures. IRQ mode support will be provided as follow up patches.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
2014-11-27 12:51:09 +05:30