ACPICA commit f005ee6b90d152c1f499efcca6b771a93903cb55

This patch splits \_SB._INI evaluation from device initialization code, so
that it can be performed before PCI_Config _REG evaluations. This is
required for the device enumeration process. Some named objects are
initialized in \_SB._INI and PCI_Config _REG evaluations may use
uninitialized named objects because of the order issue.

This must be fixed before fixing ECDT order issue. There are existing
tables allowing ECDT EC to be used for the entire device enumeration
process, but the enabling of ECDT EC is done in \_SB._INI. Thus \_SB._INI
must be the first control method evaluated in the device enumeration
process. Normally, the order should be automatically ensured by the device
enumeration process itself (for example, PCI_Config _REGs are evaluated by
the PCI bus driver when the driver is probed by the enumeration process),
but since the process is split on Linux (partially done in Linux, partially
done in ACPICA), we need to ensure this with special logics in order to be
regression safe. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/f005ee6bSigned-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit c508f8592efaa0d8197f26d7fee6382c5ac8e383

Current code flow cannot ensure _REG association can happen after the
namespace is initialized, so we move _REG association to where _REG was
about to run to fix this issue.

This issue is detected when acpi_ev_initialize_region() is invoked during
the table loading. And this is one of the most important the root cause why
ACPICA table loading is split into 2 load passes. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/c508f859
Link: https://bugs.acpica.org/show_bug.cgi?id=1252Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 5798cd6171ea38bcf4594d0ccc78870784776ba5

The patch corrects wrong condition before group MLC is disabled.

Link: https://github.com/acpica/acpica/commit/5798cd61
Link: https://bugs.acpica.org/show_bug.cgi?id=1262Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 9a6ecc9ec9ee067cad51eec539230bf494421d76

Since AE_ALREADY_EXISTS has already been converted to AE_OK in
acpi_ev_install_region_handlers(), this patch simplies a return value
check. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/9a6ecc9eSigned-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 997a90f810a4cb78604ef2e187611a181b498286

This patch enhances acpi_hw_validate_register() to sanitize register
accesses with awareness of access_width and bit_offset. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/997a90f8
Link: https://bugs.acpica.org/show_bug.cgi?id=1240Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Some compilers require parentheses to be enforced in the macro definition,
so that the macro caller side can be simpler.

This patch fixes this kind of macro issue in
ACPI_SET_BITS()/ACPI_GET_BITS(). Lv Zheng.

Link: https://bugs.acpica.org/show_bug.cgi?id=1268Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit cbcb77565c5032dd48e19b3a8a8b8704c5f29faf

This patch adds a macro ACPI_IS_POWER_OF_TWO, which can be used to
detect if a number is a power of two. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/cbcb7756Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 16cd0872a070c8d3b16b8b13c1fc90a443a6b6fe

If the definition of a control method cannot be found (probably it
is in another module/SSDT), the disassembler must try to guess
at the number of arguments to that method. This change improves
the guessing heuristic.

Link: https://github.com/acpica/acpica/commit/16cd0872Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit a240cbb93647bddf525b3daf6e9d31b8b9bca34e

Integrated most changes proposed by net_BSD.
>From joerg@net_BSD.org (Joerg Sonnenberger)
ACPICA BZ 732.

Link: https://github.com/acpica/acpica/commit/a240cbb9
Link: https://bugs.acpica.org/show_bug.cgi?id=732Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 795e136d2ac77c1c8b091fba019b5fe36a44a323

Fixes a problem with the merger of the two internal versions
of this function. Make the maximum integer width (32-bit or
64-bit) a parameter to the function so that it no longer
exclusively uses the integer width specified in the DSDT/SSDT.
ACPICA BZ 1260

Link: https://github.com/acpica/acpica/commit/795e136dSigned-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 9ed98dc36645aaeba11967722951156650d94f47

For consistency, cleanup function invocations.

Link: https://github.com/acpica/acpica/commit/9ed98dc3Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 0e6125401cf38427d5376f4bafbfb3d5a40f8467

Use local variables for access to string/value Op fields.
Move duplicate PLD string tables to a single common table.

Link: https://github.com/acpica/acpica/commit/0e612540Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit e068948f49eb61a78c211028976a174604c5644a

Fix some issues in the exutils.c file.

Link: https://github.com/acpica/acpica/commit/e068948fSigned-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 60d9cfd403a9824199b971597c930f6f563e5c71

Allows all object types to be used with Concatenate. Objects
other than Int/Str/Buf are convert to a string that contains
the type of the object. Improves the utility of the Printf
and Fprintf macros.

Adds a new file, exconcat.c

Link: https://github.com/acpica/acpica/commit/60d9cfd4Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit 5f21bddaa2cec035ca80608803ce2f0858d4f387

Small changes:
1) A couple new predefined names
2) New _HID values
3) New subtable for HEST

Link: https://github.com/acpica/acpica/commit/5f21bddaSigned-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA commit bca0c4cb063ee488c543e6f160fe89679a2338d6

Update a warning message
simplify versioning for "table too big" case.

Link: https://github.com/acpica/acpica/commit/bca0c4cbSigned-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The patch reduces source code differences between the Linux kernel and the
ACPICA upstream so that the linuxized ACPICA 20160212 release can be
applied with reduced human intervention.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
[ rjw: White space damage fixes ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There are several reports of freeze on enabling HWP (Hardware PStates)
feature on Skylake-based systems by the Intel P-states driver. The root
cause is identified as the HWP interrupts causing BIOS code to freeze.

HWP interrupts use the thermal LVT which can be handled by Linux
natively, but on the affected Skylake-based systems SMM will respond
to it by default.  This is a problem for several reasons:
 - On the affected systems the SMM thermal LVT handler is broken (it
   will crash when invoked) and a BIOS update is necessary to fix it.
 - With thermal interrupt handled in SMM we lose all of the reporting
   features of the arch/x86/kernel/cpu/mcheck/therm_throt driver.
 - Some thermal drivers like x86-package-temp depend on the thermal
   threshold interrupts signaled via the thermal LVT.
 - The HWP interrupts are useful for debugging and tuning
   performance (if the kernel can handle them).
The native handling of thermal interrupts needs to be enabled
because of that.

This requires some way to tell SMM that the OS can handle thermal
interrupts.  That can be done by using _OSC/_PDC in processor
scope very early during ACPI initialization.

The meaning of _OSC/_PDC bit 12 in processor scope is whether or
not the OS supports native handling of interrupts for Collaborative
Processor Performance Control (CPPC) notifications.  Since on
HWP-capable systems CPPC is a firmware interface to HWP, setting
this bit effectively tells the firmware that the OS will handle
thermal interrupts natively going forward.

For details on _OSC/_PDC refer to:
http://www.intel.com/content/www/us/en/standards/processor-vendor-specific-acpi-specification.html

To implement the _OSC/_PDC handshake as described, introduce a new
function, acpi_early_processor_osc(), that walks the ACPI
namespace looking for ACPI processor objects and invokes _OSC for
them with bit 12 in the capabilities buffer set and terminates the
namespace walk on the first success.

Also modify intel_thermal_interrupt() to clear HWP status bits in
the HWP_STATUS MSR to acknowledge HWP interrupts (which prevents
them from firing continuously).
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject & changelog, function rename ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 58a1fbbb ("PM / PCI / ACPI: Kick devices that might have been
reset by firmware") added a runtime resume for devices that were runtime
suspended when the system entered suspend-to-RAM.

Briefly, the motivation was to ensure that devices did not remain in a
reset-power-on state after resume, potentially preventing deep SoC-wide
low-power states from being entered on idle.

Currently we're not doing the same when leaving suspend-to-disk and this
asymmetry is a problem if drivers rely on the automatic resume triggered
by pm_complete_with_resume_check(). Fix it.

Fixes: 58a1fbbb (PM / PCI / ACPI: Kick devices that might have been reset by firmware)
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The [0 - 64k] ACPI PCI IO port resource boundary check in:

acpi_dev_ioresource_flags()

is currently applied blindly in the ACPI resource parsing to all
architectures, but only x86 suffers from that IO space limitation.

On arches (ie IA64 and ARM64) where IO space is memory mapped,
the PCI root bridges IO resource windows are firstly initialized from
the _CRS (in acpi_decode_space()) and contain the CPU physical address
at which a root bridge decodes IO space in the CPU physical address
space with the offset value representing the offset required to translate
the PCI bus address into the CPU physical address.

The IO resource windows are then parsed and updated in arch code
before creating and enumerating PCI buses (eg IA64 add_io_space())
to map in an arch specific way the obtained CPU physical address range
to a slice of virtual address space reserved to map PCI IO space,
ending up with PCI bridges resource windows containing IO
resources like the following on a working IA64 configuration:

PCI host bridge to bus 0000:00
pci_bus 0000:00: root bus resource [io  0x1000000-0x100ffff window] (bus
address [0x0000-0xffff])
pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000fffff window]
pci_bus 0000:00: root bus resource [mem 0x80000000-0x8fffffff window]
pci_bus 0000:00: root bus resource [mem 0x80004000000-0x800ffffffff window]
pci_bus 0000:00: root bus resource [bus 00]

This implies that the [0 - 64K] check in acpi_dev_ioresource_flags()
leaves platforms with memory mapped IO space (ie IA64) broken (ie kernel
can't claim IO resources since the host bridge IO resource is disabled
and discarded by ACPI core code, see log on IA64 with missing root bridge
IO resource, silently filtered by current [0 - 64k] check in
acpi_dev_ioresource_flags()):

PCI host bridge to bus 0000:00
pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000fffff window]
pci_bus 0000:00: root bus resource [mem 0x80000000-0x8fffffff window]
pci_bus 0000:00: root bus resource [mem 0x80004000000-0x800ffffffff window]
pci_bus 0000:00: root bus resource [bus 00]

[...]

pci 0000:00:03.0: [1002:515e] type 00 class 0x030000
pci 0000:00:03.0: reg 0x10: [mem 0x80000000-0x87ffffff pref]
pci 0000:00:03.0: reg 0x14: [io  0x1000-0x10ff]
pci 0000:00:03.0: reg 0x18: [mem 0x88020000-0x8802ffff]
pci 0000:00:03.0: reg 0x30: [mem 0x88000000-0x8801ffff pref]
pci 0000:00:03.0: supports D1 D2
pci 0000:00:03.0: can't claim BAR 1 [io  0x1000-0x10ff]: no compatible
bridge window

For this reason, the IO port resources boundaries check in generic ACPI
parsing code should be guarded with a CONFIG_X86 guard so that more arches
(ie ARM64) can benefit from the generic ACPI resources parsing interface
without incurring in unexpected resource filtering, fixing at the same
time current breakage on IA64.

This patch factors out IO ports boundary [0 - 64k] check in generic ACPI
code and makes the IO space check X86 specific to make sure that IO
space resources are usable on other arches too.

Fixes: 3772aea7 (ia64/PCI/ACPI: Use common ACPI resource parsing interface for host bridge)
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

obj->buffer.pointer[i] should be cast to u64 to prevent an unintentional
sign extension.  For example, if pointer[7] is 0x80, then the value
0xffffffffff000000 is or'd into mask rather than the intended value
0xff00000000000000

Detected with static analysis by CoverityScan
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

When an ACPI node has both ACPI device nodes and ACPI data nodes,
acpi_get_next_subnode() will return the ACPI data nodes of its last
parsed child.

To avoid that, make acpi_get_next_subnode() go back to the original
ACPI device object when all of the device node children of it have
been found already.
Signed-off-by: NIrina Tirdea <irina.tirdea@intel.com>
[ rjw: Changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add device HID AMDI0020 to match the AMD ACPI Vendor ID (AMDI) as
registered in http://www.uefi.org/acpi_id_list, and the UART
controller on future AMD paltform will use the HID instead of AMD0020.
Signed-off-by: NWang Hongcheng <annie.wang@amd.com>
Acked-by: NKen Xue <Ken.Xue@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

$ make tags
  GEN     tags
ctags: Warning: drivers/acpi/processor_idle.c:64: null expansion of name pattern "\1"
ctags: Warning: drivers/xen/events/events_2l.c:41: null expansion of name pattern "\1"
ctags: Warning: kernel/locking/lockdep.c:151: null expansion of name pattern "\1"
ctags: Warning: kernel/rcu/rcutorture.c:133: null expansion of name pattern "\1"
ctags: Warning: kernel/rcu/rcutorture.c:135: null expansion of name pattern "\1"
ctags: Warning: kernel/workqueue.c:323: null expansion of name pattern "\1"
ctags: Warning: net/ipv4/syncookies.c:53: null expansion of name pattern "\1"
ctags: Warning: net/ipv6/syncookies.c:44: null expansion of name pattern "\1"
ctags: Warning: net/rds/page.c:45: null expansion of name pattern "\1"

Which are all the result of the DEFINE_PER_CPU pattern:

  scripts/tags.sh:200:	'/\<DEFINE_PER_CPU([^,]*, *\([[:alnum:]_]*\)/\1/v/'
  scripts/tags.sh:201:	'/\<DEFINE_PER_CPU_SHARED_ALIGNED([^,]*, *\([[:alnum:]_]*\)/\1/v/'

The below cures them. All except the workqueue one are within reasonable
distance of the 80 char limit. TJ do you have any preference on how to
fix the wq one, or shall we just not care its too long?
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

erst_init currently leaks resources allocated from its call to
apei_resources_init(). The data allocated there gets copied
into apei_resources_all and can be freed when we're done with it.
Signed-off-by: NJosh Hunt <johunt@akamai.com>
Reviewed-by: NChen, Gong <gong.chen@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We leak the NVS and arch resources (if used), in apei_resources_request.
They are allocated to make sure we exclude them from the APEI resources,
but they are never freed at the end of the function. Free them now.
Signed-off-by: NJosh Hunt <johunt@akamai.com>
Reviewed-by: NChen, Gong <gong.chen@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add device HID AMDI0010 to match the AMD ACPI Vendor ID (AMDI) that
was registered in http://www.uefi.org/acpi_id_list, and the I2C
controller on future AMD paltform will use the HID instead of AMD0010.
Signed-off-by: NXiangliang Yu <Xiangliang.Yu@amd.com>
Acked-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It is reported that the following commit triggers regressions:
 Linux commit: efaed9be
 ACPICA commit: 31178590dde82368fdb0f6b0e466b6c0add96c57
 Subject: ACPICA: Events: Enhance acpi_ev_execute_reg_method() to
          ensure no _REG evaluations can happen during OS early boot
          stages

This is because that the ECDT support is not corrected in Linux, and Linux
requires to execute _REG for ECDT (though this sounds so wrong), we need to
ensure acpi_gbl_namespace_initialized is set before ECDT probing in order
for _REG to be executed. Since we have to move
"acpi_gbl_namespace_initialized = TRUE" to the initialization step
happening before ECDT probing, acpi_load_tables() is the best candidate for
now. Thus this patch fixes the regression by doing so.

But if the ECDT support is fixed, Linux will not execute _REG for ECDT, and
ECDT probing will happen before acpi_load_tables(). At that time, we still
want to ensure acpi_gbl_namespace_initialized is set after executing
acpi_ns_initialize_objects() (under the condition of
acpi_gbl_group_module_level_code = FALSE), this patch also moves
acpi_ns_initialize_objects() to acpi_load_tables() accordingly.

Since acpi_ns_initialize_objects() doesn't seem to be skippable, this
patch also removes ACPI_NO_OBJECT_INIT for the one invoked in
acpi_load_tables(). And since the default region handlers should always be
installed before loading the tables, this patch also removes useless
acpi_gbl_group_module_level_code check accordingly. Reported by Chris
Bainbridge, Fixed by Lv Zheng.

Fixes: efaed9be (ACPICA: Events: Enhance acpi_ev_execute_reg_method() to ensure no _REG evaluations can happen during OS early boot stages)
Reported-and-tested-by: NChris Bainbridge <chris.bainbridge@gmail.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch adds support to install tables from initrd.

If a table in the initrd wasn't used by the override mechanism,
the table would be installed after initializing all RSDT/XSDT
tables.

Link: https://lkml.org/lkml/2014/2/28/368Reported-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch cleans up the initrd table override code by merging
redundant logics and re-ordering code blocks.

No functional changes.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

element is &package->package.elements[i] which can never be NULL
so the check to see if it is NULL is redundant and can be removed.

Detected with static analysis by CoverityScan
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Some HP laptops seem to have invalid 64 bit FADT X_PM* addresses
which are causing various boot issues.  In these cases, it would
be useful to force ACPI to use the valid legacy 32 bit equivalent
PM addresses.  Add a acpi_force_32bit_fadt_addr to set the ACPICA
acpi_gbl_use32_bit_fadt_addresses to TRUE to force this override.

Link: https://bugs.launchpad.net/bugs/1529381Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The Kconfig currently controlling compilation of this code is:

drivers/acpi/Kconfig:config CRC_PMIC_OPREGION
drivers/acpi/Kconfig:   bool "ACPI operation region support for CrystalCove PMIC"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple modular references, so that when reading
the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: NAaron Lu <aaron.lu@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The Kconfig currently controlling compilation of this code is:

config ACPI_APEI_GHES
      bool "APEI Generic Hardware Error Source"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We replace module.h with moduleparam.h as we are keeping the
pre-existing module_param that the file has, as currently that is
the easiest way to maintain compatibility with the existing boot
arg use cases.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The Kconfig for this driver is currently:

config ACPI_BGRT
    bool "Boottime Graphics Resource Table support"

...meaning that it currently is not being built as a module by anyone.
Lets remove all modular references, so that when reading the driver
there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We also delete the MODULE_LICENSE tag etc. since all that information
was (or is now) contained at the top of the file in the comments.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The ACPI spec defines Minimum Request Turnaround Time(MRTT) and
Maximum Periodic Access Rate(MPAR) to prevent the OSPM from sending
too many requests than the platform can handle. For further details
on these parameters please refer to section 14.1.3 of ACPI 6.0 spec.

This patch includes MRTT/MPAR in deciding if or when a CPPC request
can be sent to the platform to make sure CPPC implementation is
compliant to the spec.
Signed-off-by: NPrashanth Prakash <pprakash@codeaurora.org>
Acked-by: NAshwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We do not have a strict read/write order requirement while accessing
PCC subspace. The only requirement is all access should be committed
before triggering the PCC doorbell to transfer the ownership of PCC
to the platform and this requirement is enforced by the PCC driver.

Profiling on a many core system shows improvement of about 1.8us on
average per freq change request(about 10% improvement on average).
Since these operations are executed while holding the pcc_lock,
reducing this time helps the CPPC implementation to scale much
better as the number of cores increases.
Signed-off-by: NPrashanth Prakash <pprakash@codeaurora.org>
Acked-by: NAshwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

cpc_read and cpc_write are used while holding the pcc_lock spin_lock,
so they need to be as fast as possible. acpi_os_read/write_memory
APIs linearly search through a list for cached mapping which is
quite expensive. Since the PCC subspace is already mapped into
virtual address space during initialization, we can just add the
offset and access the necessary CPPC registers.

This patch + similar changes to PCC driver reduce the time per freq.
transition from around 200us to about 20us for the CPPC cpufreq
driver.
Signed-off-by: NPrashanth Prakash <pprakash@codeaurora.org>
Acked-by: NAshwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Previously the send_pcc_cmd() code checked if the
PCC operation had completed before returning from
the function. This check was performed regardless
of the PCC op type (i.e. Read/Write). Knowing
the type of cmd can be used to optimize the check
and avoid needless waiting. e.g. with Write ops,
the actual Writing is done before calling send_pcc_cmd().
And the subsequent Writes will check if the channel is
free at the entry of send_pcc_cmd() anyway.

However, for Read cmds, we need to wait for the cmd
completion bit to be flipped, since the actual Read
ops follow after returning from the send_pcc_cmd(). So,
only do the looping check at the end for Read ops.

Also, instead of using udelay() calls, use ktime as a
means to check for deadlines. The current deadline
in which the Remote should flip the cmd completion bit
is defined as N * Nominal latency. Where N is arbitrary
and large enough to work on slow emulators and Nominal
latency comes from the ACPI table (PCCT). This helps
in working around the CONFIG_HZ effects on udelay()
and also avoids needing different ACPI tables for Silicon
and Emulation platforms.
Signed-off-by: NAshwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: NPrashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

device_decode is now no longer used, so we may as well remove it.
Fixes gcc 6 warning:

drivers/acpi/acpi_video.c:221:19: warning: ‘device_decode’ defined
 but not used [-Wunused-const-variable]
 static const char device_decode[][30] = {
                   ^~~~~~~~~~~~~
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>