[PATCH v1 2/2] mailbox: Add Broadcom STB mailbox driver

[Florian Fainelli]

Hi Jim,

On 9/15/2020 12:31 PM, Jim Quinlan wrote:
> This is a simple mailbox driver to be used by the SCMI protocol stack.  It
> only implements the agent-to-platform channel; we may implement the
> platform-to-agent channel in the future.  An unusual aspect of this driver
> is how the completion of an SCMI message is indicated.  An SCMI message is
> initiated with an ARM SMC call, but the return of this call does not
> indicate the execution or completion of the message.  Rather, the message's
> completion is signaled by an interrupt.
> 
> Signed-off-by: Jim Quinlan <james.quinlan at broadcom.com>
> Signed-off-by: Florian Fainelli <f.fainelli at gmail.com>
> ---
>   drivers/mailbox/Kconfig           |  13 +++
>   drivers/mailbox/Makefile          |   2 +
>   drivers/mailbox/brcmstb-mailbox.c | 173 ++++++++++++++++++++++++++++++
>   3 files changed, 188 insertions(+)
>   create mode 100644 drivers/mailbox/brcmstb-mailbox.c
> 
> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> index 05b1009e2820..bebf7da778bc 100644
> --- a/drivers/mailbox/Kconfig
> +++ b/drivers/mailbox/Kconfig
> @@ -254,4 +254,17 @@ config QCOM_IPCC
>   	  acts as an interrupt controller for receiving interrupts from clients.
>   	  Say Y here if you want to build this driver.
>   
> +config BRCMSTB_MBOX
> +	tristate "Broadcom STB Mailbox"
> +	depends on ARM64 || ARM
> +	depends on ARM_SCMI_PROTOCOL && ARCH_BRCMSTB
> +	depends on SMP

We can actually remove the SMP dependency cannot we? This was needed 
back when we used the hackish way of hooking to IPIs in the downstream 
kernel which we fortunately no longer do.
-- 
Florian