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2017-03-02x86/platform/intel/iosf_mbi: Add a PMIC bus access notifierHans de Goede
Some drivers may need to acquire P-Unit managed resources from interrupt context, where they cannot call iosf_mbi_punit_acquire(). This commit adds a notifier chain which allows a driver to get notified (in a process context) before other drivers start accessing the PMIC bus, so that the driver can acquire any resources, which it may need during the window the other driver is accessing the PMIC, before hand. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=155241 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Tested-by: tagorereddy <tagore.chandan@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-02-26x86/platform/intel/iosf_mbi: Add a mutex for P-Unit accessHans de Goede
One some systems the P-Unit accesses the PMIC to change various voltages through the same bus as other kernel drivers use for e.g. battery monitoring. If a driver sends requests to the P-Unit which require the P-Unit to access the PMIC bus while another driver is also accessing the PMIC bus various bad things happen. This commit adds a mutex to protect the P-Unit against simultaneous accesses and 2 functions to lock / unlock this mutex. Note on these systems the i2c-bus driver will request a sempahore from the P-Unit for exclusive access to the PMIC bus when i2c drivers are accessing it, but this does not appear to be sufficient, we still need to avoid making certain P-Unit requests during the access window to avoid problems. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=155241 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Tested-by: tagorereddy <tagore.chandan@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-2-hdegoede@redhat.com
2016-01-07ACPI / LPSS: override power state for LPSS DMA deviceAndy Shevchenko
This is a third approach to workaround long standing issue with LPSS on BayTrail. First one [1] was reverted since it didn't resolve the issue comprehensively. Second one [2] was rejected by internal review. The LPSS DMA controller does not have neither _PS0 nor _PS3 method. Moreover it can be powered off automatically whenever the last LPSS device goes down. In case of no power any access to the DMA controller will hang the system. The behaviour is reproduced on some HP laptops based on Intel BayTrail [3,4] as well as on ASuS T100TA transformer. Power on the LPSS island through the registers accessible in a specific way. [1] http://www.spinics.net/lists/linux-acpi/msg53963.html [2] https://bugzilla.redhat.com/attachment.cgi?id=1066779&action=diff [3] https://bugzilla.redhat.com/show_bug.cgi?id=1184273 [4] http://www.spinics.net/lists/dmaengine/msg01514.html Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-09x86/platform/iosf_mbi: Remove duplicate definitionsAndy Shevchenko
The read and write opcodes are global for all units on SoC and even across Intel SoCs. Remove duplication of corresponding constants. At the same time convert all current users. No functional change. Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Boon Leong Ong <boon.leong.ong@intel.com> Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-16x86/platform/iosf_mbi: Source cleanupAndy Shevchenko
- Move the static variables to one place - Fix indentations in the header - Correct comments No functional change. [ tglx: Massaged changelog ] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: David E . Box <david.e.box@linux.intel.com> Link: http://lkml.kernel.org/r/1436366709-17683-5-git-send-email-andriy.shevchenko@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-09x86, iosf: Added Quark MBI identifiersOng Boon Leong
Added all the MBI units below and their associated read/write opcodes: - Host Bridge Arbiter - Host Bridge - Remote Management Unit - Memory Manager & eSRAM - SoC Unit Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com> Link: http://lkml.kernel.org/r/1399668248-24199-3-git-send-email-david.e.box@linux.intel.com Signed-off-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-09x86, iosf: Make IOSF driver modular and usable by more driversDavid E. Box
Currently drivers that run on non-IOSF systems (Core/Xeon) can't use the IOSF driver on SOC's without selecting it which forces an unnecessary and limiting dependency. Provides dummy functions to allow these modules to conditionally use the driver on IOSF equipped platforms without impacting their ability to compile and load on non-IOSF platforms. Build default m to ensure availability on x86 SOC's. Signed-off-by: David E. Box <david.e.box@linux.intel.com> Link: http://lkml.kernel.org/r/1399668248-24199-2-git-send-email-david.e.box@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-08arch: x86: New MailBox support driver for Intel SOC'sDavid E. Box
Current Intel SOC cores use a MailBox Interface (MBI) to provide access to configuration registers on devices (called units) connected to the system fabric. This is a support driver that implements access to this interface on those platforms that can enumerate the device using PCI. Initial support is for BayTrail, for which port definitons are provided. This is a requirement for implementing platform specific features (e.g. RAPL driver requires this to perform platform specific power management using the registers in PUNIT). Dependant modules should select IOSF_MBI in their respective Kconfig configuraiton. Serialized access is handled by all exported routines with spinlocks. The API includes 3 functions for access to unit registers: int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr) int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr) int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask) port: indicating the unit being accessed opcode: the read or write port specific opcode offset: the register offset within the port mdr: the register data to be read, written, or modified mask: bit locations in mdr to change Returns nonzero on error Note: GPU code handles access to the GFX unit. Therefore access to that unit with this driver is disallowed to avoid conflicts. Signed-off-by: David E. Box <david.e.box@linux.intel.com> Link: http://lkml.kernel.org/r/1389216471-734-1-git-send-email-david.e.box@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Matthew Garrett <mjg59@srcf.ucam.org>