Commit Graph

7 Commits

Author SHA1 Message Date
Will Deacon
6e085e0ac9 arm/arm64: Probe for the presence of KVM hypervisor
Although the SMCCC specification provides some limited functionality for
describing the presence of hypervisor and firmware services, this is
generally applicable only to functions designated as "Arm Architecture
Service Functions" and no portable discovery mechanism is provided for
standard hypervisor services, despite having a designated range of
function identifiers reserved by the specification.

In an attempt to avoid the need for additional firmware changes every
time a new function is added, introduce a UID to identify the service
provider as being compatible with KVM. Once this has been established,
additional services can be discovered via a feature bitmap.

Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
[maz: move code to its own file, plug it into PSCI]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201209060932.212364-2-jianyong.wu@arm.com
2021-03-31 09:16:55 +01:00
Andre Przywara
a37e31fc97 firmware: smccc: Introduce SMCCC TRNG framework
The ARM DEN0098 document describe an SMCCC based firmware service to
deliver hardware generated random numbers. Its existence is advertised
according to the SMCCC v1.1 specification.

Add a (dummy) call to probe functions implemented in each architecture
(ARM and arm64), to determine the existence of this interface.
For now this return false, but this will be overwritten by each
architecture's support patch.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-21 17:42:46 +00:00
Sudeep Holla
6825f17c95 firmware: smccc: Export both smccc functions
We need to export both arm_smccc_1_1_get_conduit and arm_smccc_get_version
to allow several modules make use of them. Arm FFA, Arm SCMI and PTP
drivers are few drivers that are planning to use these functions.

Let us export them in preparation to add support for SCMI as module.

Link: https://lore.kernel.org/r/20200907195046.56615-2-sudeep.holla@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-14 07:30:36 +01:00
Sudeep Holla
821b67fa46 firmware: smccc: Add ARCH_SOC_ID support
SMCCC v1.2 adds a new optional function SMCCC_ARCH_SOC_ID to obtain a
SiP defined SoC identification value. Add support for the same.

Also using the SoC bus infrastructure, let us expose the platform
specific SoC atrributes under sysfs.

There are various ways in which it can be represented in shortened form
for efficiency and ease of parsing for userspace. The chosen form is
described in the ABI document.

Link: https://lore.kernel.org/r/20200625095939.50861-1-sudeep.holla@arm.com
Cc: Etienne Carriere <etienne.carriere@st.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-06 09:48:06 +01:00
Sudeep Holla
a4fb174651 firmware: smccc: Add function to fetch SMCCC version
For backward compatibility reasons, PSCI maintains SMCCC version as
SMCCC didn't provide ARM_SMCCC_VERSION_FUNC_ID until v1.1.

PSCI initialises both the SMCCC version and conduit. Similar to the
conduit, let us provide accessors to fetch the SMCCC version also so
that other SMCCC v1.1+ features can use it.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Etienne Carriere <etienne.carriere@st.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Etienne Carriere <etienne.carriere@st.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200518091222.27467-7-sudeep.holla@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-20 19:10:37 +01:00
Sudeep Holla
f2ae97062a firmware: smccc: Refactor SMCCC specific bits into separate file
In order to add newer SMCCC v1.1+ functionality and to avoid cluttering
PSCI firmware driver with SMCCC bits, let us move the SMCCC specific
details under drivers/firmware/smccc/smccc.c

We can also drop conduit and smccc_version from psci_operations structure
as SMCCC was the sole user and now it maintains those.

No functionality change in this patch though.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Etienne Carriere <etienne.carriere@st.com>
Reviewed-by: Etienne Carriere <etienne.carriere@st.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200518091222.27467-6-sudeep.holla@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-20 19:10:37 +01:00
Sudeep Holla
e5bfb21d98 firmware: smccc: Add HAVE_ARM_SMCCC_DISCOVERY to identify SMCCC v1.1 and above
SMCCC v1.0 lacked discoverability of version and features. To accelerate
adoption of few mitigations and protect systems more rapidly from various
vulnerability, PSCI v1.0 was updated to add SMCCC discovery mechanism
though the PSCI firmware implementation of PSCI_FEATURES(SMCCC_VERSION)
which returns success on firmware compliant to SMCCC v1.1 and above.

This inturn makes SMCCC v1.1 and above dependent on ARM_PSCI_FW for
backward compatibility. Let us introduce a new hidden config for the
same to build more features on top of SMCCC v1.1 and above.

While at it, also sort alphabetically the psci entry.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Etienne Carriere <etienne.carriere@st.com>
Reviewed-by: Etienne Carriere <etienne.carriere@st.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200518091222.27467-2-sudeep.holla@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-20 19:10:37 +01:00