v4.19.13 snapshot.
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
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+menuconfig MAILBOX
+ bool "Mailbox Hardware Support"
+ help
+ Mailbox is a framework to control hardware communication between
+ on-chip processors through queued messages and interrupt driven
+ signals. Say Y if your platform supports hardware mailboxes.
+
+if MAILBOX
+
+config ARM_MHU
+ tristate "ARM MHU Mailbox"
+ depends on ARM_AMBA
+ help
+ Say Y here if you want to build the ARM MHU controller driver.
+ The controller has 3 mailbox channels, the last of which can be
+ used in Secure mode only.
+
+config IMX_MBOX
+ tristate "i.MX Mailbox"
+ depends on ARCH_MXC || COMPILE_TEST
+ help
+ Mailbox implementation for i.MX Messaging Unit (MU).
+
+config PLATFORM_MHU
+ tristate "Platform MHU Mailbox"
+ depends on OF
+ depends on HAS_IOMEM
+ help
+ Say Y here if you want to build a platform specific variant MHU
+ controller driver.
+ The controller has a maximum of 3 mailbox channels, the last of
+ which can be used in Secure mode only.
+
+config PL320_MBOX
+ bool "ARM PL320 Mailbox"
+ depends on ARM_AMBA
+ help
+ An implementation of the ARM PL320 Interprocessor Communication
+ Mailbox (IPCM), tailored for the Calxeda Highbank. It is used to
+ send short messages between Highbank's A9 cores and the EnergyCore
+ Management Engine, primarily for cpufreq. Say Y here if you want
+ to use the PL320 IPCM support.
+
+config OMAP2PLUS_MBOX
+ tristate "OMAP2+ Mailbox framework support"
+ depends on ARCH_OMAP2PLUS
+ help
+ Mailbox implementation for OMAP family chips with hardware for
+ interprocessor communication involving DSP, IVA1.0 and IVA2 in
+ OMAP2/3; or IPU, IVA HD and DSP in OMAP4/5. Say Y here if you
+ want to use OMAP2+ Mailbox framework support.
+
+config OMAP_MBOX_KFIFO_SIZE
+ int "Mailbox kfifo default buffer size (bytes)"
+ depends on OMAP2PLUS_MBOX
+ default 256
+ help
+ Specify the default size of mailbox's kfifo buffers (bytes).
+ This can also be changed at runtime (via the mbox_kfifo_size
+ module parameter).
+
+config ROCKCHIP_MBOX
+ bool "Rockchip Soc Intergrated Mailbox Support"
+ depends on ARCH_ROCKCHIP || COMPILE_TEST
+ help
+ This driver provides support for inter-processor communication
+ between CPU cores and MCU processor on Some Rockchip SOCs.
+ Please check it that the Soc you use have Mailbox hardware.
+ Say Y here if you want to use the Rockchip Mailbox support.
+
+config PCC
+ bool "Platform Communication Channel Driver"
+ depends on ACPI
+ default n
+ help
+ 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). Select this driver if your platform implements the
+ PCC clients mentioned above.
+
+config ALTERA_MBOX
+ tristate "Altera Mailbox"
+ depends on HAS_IOMEM
+ help
+ An implementation of the Altera Mailbox soft core. It is used
+ to send message between processors. Say Y here if you want to use the
+ Altera mailbox support.
+
+config BCM2835_MBOX
+ tristate "BCM2835 Mailbox"
+ depends on ARCH_BCM2835
+ help
+ An implementation of the BCM2385 Mailbox. It is used to invoke
+ the services of the Videocore. Say Y here if you want to use the
+ BCM2835 Mailbox.
+
+config STI_MBOX
+ tristate "STI Mailbox framework support"
+ depends on ARCH_STI && OF
+ help
+ Mailbox implementation for STMicroelectonics family chips with
+ hardware for interprocessor communication.
+
+config TI_MESSAGE_MANAGER
+ tristate "Texas Instruments Message Manager Driver"
+ depends on ARCH_KEYSTONE
+ help
+ An implementation of Message Manager slave driver for Keystone
+ architecture SoCs from Texas Instruments. Message Manager is a
+ communication entity found on few of Texas Instrument's keystone
+ architecture SoCs. These may be used for communication between
+ multiple processors within the SoC. Select this driver if your
+ platform has support for the hardware block.
+
+config HI3660_MBOX
+ tristate "Hi3660 Mailbox" if EXPERT
+ depends on (ARCH_HISI || COMPILE_TEST)
+ depends on OF
+ default ARCH_HISI
+ help
+ An implementation of the hi3660 mailbox. It is used to send message
+ between application processors and other processors/MCU/DSP. Select
+ Y here if you want to use Hi3660 mailbox controller.
+
+config HI6220_MBOX
+ tristate "Hi6220 Mailbox" if EXPERT
+ depends on (ARCH_HISI || COMPILE_TEST)
+ depends on OF
+ default ARCH_HISI
+ help
+ An implementation of the hi6220 mailbox. It is used to send message
+ between application processors and MCU. Say Y here if you want to
+ build Hi6220 mailbox controller driver.
+
+config MAILBOX_TEST
+ tristate "Mailbox Test Client"
+ depends on OF
+ depends on HAS_IOMEM
+ help
+ Test client to help with testing new Controller driver
+ implementations.
+
+config QCOM_APCS_IPC
+ tristate "Qualcomm APCS IPC driver"
+ depends on ARCH_QCOM || COMPILE_TEST
+ help
+ Say y here to enable support for the APCS IPC mailbox driver,
+ providing an interface for invoking the inter-process communication
+ signals from the application processor to other masters.
+
+config TEGRA_HSP_MBOX
+ bool "Tegra HSP (Hardware Synchronization Primitives) Driver"
+ depends on ARCH_TEGRA
+ help
+ The Tegra HSP driver is used for the interprocessor communication
+ between different remote processors and host processors on Tegra186
+ and later SoCs. Say Y here if you want to have this support.
+ If unsure say N.
+
+config XGENE_SLIMPRO_MBOX
+ tristate "APM SoC X-Gene SLIMpro Mailbox Controller"
+ depends on ARCH_XGENE
+ help
+ An implementation of the APM X-Gene Interprocessor Communication
+ Mailbox (IPCM) between the ARM 64-bit cores and SLIMpro controller.
+ It is used to send short messages between ARM64-bit cores and
+ the SLIMpro Management Engine, primarily for PM. Say Y here if you
+ want to use the APM X-Gene SLIMpro IPCM support.
+
+config BCM_PDC_MBOX
+ tristate "Broadcom FlexSparx DMA Mailbox"
+ depends on ARCH_BCM_IPROC || COMPILE_TEST
+ help
+ Mailbox implementation for the Broadcom FlexSparx DMA ring manager,
+ which provides access to various offload engines on Broadcom
+ SoCs, including FA2/FA+ on Northstar Plus and PDC on Northstar 2.
+
+config BCM_FLEXRM_MBOX
+ tristate "Broadcom FlexRM Mailbox"
+ depends on ARM64
+ depends on ARCH_BCM_IPROC || COMPILE_TEST
+ select GENERIC_MSI_IRQ_DOMAIN
+ default m if ARCH_BCM_IPROC
+ help
+ Mailbox implementation of the Broadcom FlexRM ring manager,
+ which provides access to various offload engines on Broadcom
+ SoCs. Say Y here if you want to use the Broadcom FlexRM.
+
+config STM32_IPCC
+ tristate "STM32 IPCC Mailbox"
+ depends on MACH_STM32MP157
+ help
+ Mailbox implementation for STMicroelectonics STM32 family chips
+ with hardware for Inter-Processor Communication Controller (IPCC)
+ between processors. Say Y here if you want to have this support.
+
+config MTK_CMDQ_MBOX
+ tristate "MediaTek CMDQ Mailbox Support"
+ depends on ARCH_MEDIATEK || COMPILE_TEST
+ select MTK_INFRACFG
+ help
+ Say yes here to add support for the MediaTek Command Queue (CMDQ)
+ mailbox driver. The CMDQ is used to help read/write registers with
+ critical time limitation, such as updating display configuration
+ during the vblank.
+endif