Re: [PATCH 0/9] bus: brcmstb_gisb: add support for GISBv7 arbiter

From: Mark Rutland
Date: Fri Mar 24 2017 - 11:04:34 EST


On Fri, Mar 24, 2017 at 07:46:23AM -0700, Doug Berger wrote:
> This patch set contains changes to enable the GISB arbiter driver
> on the latest ARM64 architecture Set-Top Box chips from Broadcom.
>
> This driver relies on being able to hook the abort handlers of
> the processor core that are triggered by bus error signals
> generated by the GISB bus arbiter hardware found in BCM7XXX chips.

Ugh; hardware generating asynchonous exceptions is hideous. I had hoped
that such hardware was a thing of the past.

Under what circumstances does the GISB bus arbiter generate these
aborts?

Mark.

> The first three patches are based on the arm64/for-next/core
> branch to enable this functionality for the arm64 architecture.
>
> The remaining patches correct some issues with the existing driver,
> add the ARM64 architecture specific support to the driver, and
> finally add the new register map for the GISBv7 hardware first
> appearing in the BCM7278 device.
>
> Doug Berger (7):
> arm64: mm: mark fault_info __ro_after_init
> arm64: mm: install SError abort handler
> bus: brcmstb_gisb: Use register offsets with writes too
> bus: brcmstb_gisb: Correct hooking of ARM aborts
> bus: brcmstb_gisb: correct support for 64-bit address output
> bus: brcmstb_gisb: add ARM64 SError support
> bus: brcmstb_gisb: update to support new revision
>
> Florian Fainelli (2):
> arm64: mm: Allow installation of memory abort handlers
> bus: brcmstb_gisb: Add ARM64 support
>
> .../devicetree/bindings/bus/brcm,gisb-arb.txt | 3 +-
> arch/arm64/include/asm/system_misc.h | 5 +
> arch/arm64/kernel/entry.S | 69 ++++++++++++--
> arch/arm64/mm/fault.c | 48 +++++++++-
> drivers/bus/Kconfig | 2 +-
> drivers/bus/brcmstb_gisb.c | 106 ++++++++++++++++-----
> 6 files changed, 197 insertions(+), 36 deletions(-)
>
> --
> 2.12.0
>