Commit graph

30 commits

Author SHA1 Message Date
Boyan Karatotev
da305ec75d feat(arm): convert arm platforms to expect a wakeup
Newer cores in upcoming platforms may refuse to power down. The PSCI
library is already prepared for this so convert platform code to also
allow this. This is simple - drop the `wfi` + panic and let common code
deal with the fallout. The end result will be the same (sans the
message) except the platform will have fewer responsibilities. The only
exception is for cores being signalled to power off gracefully ahead of
system reset. That path must also be terminal so replace the end with
the same psci_pwrdown_cpu_end() to behave the same as the generic
implementation. It will handle wakeups and panic, hoping that the system
gets reset from under it. The dmb is upgraded to a dsb so no functional
change.

Change-Id: I381f96bec8532bda6ccdac65de57971aac42e7e8
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
2025-02-03 14:29:47 +00:00
Boyan Karatotev
2b5e00d4ea feat(psci): allow cores to wake up from powerdown
The simplistic view of a core's powerdown sequence is that power is
atomically cut upon calling `wfi`. However, it turns out that it has
lots to do - it has to talk to the interconnect to exit coherency, clean
caches, check for RAS errors, etc. These take significant amounts of
time and are certainly not atomic. As such there is a significant window
of opportunity for external events to happen. Many of these steps are
not destructive to context, so theoretically, the core can just "give
up" half way (or roll certain actions back) and carry on running. The
point in this sequence after which roll back is not possible is called
the point of no return.

One of these actions is the checking for RAS errors. It is possible for
one to happen during this lengthy sequence, or at least remain
undiscovered until that point. If the core were to continue powerdown
when that happens, there would be no (easy) way to inform anyone about
it. Rejecting the powerdown and letting software handle the error is the
best way to implement this.

Arm cores since at least the a510 have included this exact feature. So
far it hasn't been deemed necessary to account for it in firmware due to
the low likelihood of this happening. However, events like GIC wakeup
requests are much more probable. Older cores will powerdown and
immediately power back up when this happens. Travis and Gelas include a
feature similar to the RAS case above, called powerdown abandon. The
idea is that this will improve the latency to service the interrupt by
saving on work which the core and software need to do.

So far firmware has relied on the `wfi` being the point of no return and
if it doesn't explicitly detect a pending interrupt quite early on, it
will embark onto a sequence that it expects to end with shutdown. To
accommodate for it not being a point of no return, we must undo all of
the system management we did, just like in the warm boot entrypoint.

To achieve that, the pwr_domain_pwr_down_wfi hook must not be terminal.
Most recent platforms do some platform management and finish on the
standard `wfi`, followed by a panic or an endless loop as this is
expected to not return. To make this generic, any platform that wishes
to support wakeups must instead let common code call
`psci_power_down_wfi()` right after. Besides wakeups, this lets common
code handle powerdown errata better as well.

Then, the CPU_OFF case is simple - PSCI does not allow it to return. So
the best that can be done is to attempt the `wfi` a few times (the
choice of 32 is arbitrary) in the hope that the wakeup is transient. If
it isn't, the only choice is to panic, as the system is likely to be in
a bad state, eg. interrupts weren't routed away. The same applies for
SYSTEM_OFF, SYSTEM_RESET, and SYSTEM_RESET2. There the panic won't
matter as the system is going offline one way or another. The RAS case
will be considered in a separate patch.

Now, the CPU_SUSPEND case is more involved. First, to powerdown it must
wipe its context as it is not written on warm boot. But it cannot be
overwritten in case of a wakeup. To avoid the catch 22, save a copy that
will only be used if powerdown fails. That is about 500 bytes on the
stack so it hopefully doesn't tip anyone over any limits. In future that
can be avoided by having a core manage its own context.

Second, when the core wakes up, it must undo anything it did to prepare
for poweroff, which for the cores we care about, is writing
CPUPWRCTLR_EL1.CORE_PWRDN_EN. The least intrusive for the cpu library
way of doing this is to simply call the power off hook again and have
the hook toggle the bit. If in the future there need to be more complex
sequences, their direction can be advised on the value of this bit.

Third, do the actual "resume". Most of the logic is already there for
the retention suspend, so that only needs a small touch up to apply to
the powerdown case as well. The missing bit is the powerdown specific
state management. Luckily, the warmboot entrypoint does exactly that
already too, so steal that and we're done.

All of this is hidden behind a FEAT_PABANDON flag since it has a large
memory and runtime cost that we don't want to burden non pabandon cores
with.

Finally, do some function renaming to better reflect their purpose and
make names a little bit more consistent.

Change-Id: I2405b59300c2e24ce02e266f91b7c51474c1145f
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
2025-02-03 14:29:47 +00:00
Boyan Karatotev
3b8021058a perf(psci): pass my_core_pos around instead of calling it repeatedly
On some platforms plat_my_core_pos is a nontrivial function that takes a
bit of time and the compiler really doesn't like to inline. In the PSCI
library, at least, we have no need to keep repeatedly calling it and we
can instead pass it around as an argument. This saves on a lot of
redundant calls, speeding the library up a bit.

Change-Id: I137f69bea80d7cac90d7a20ffe98e1ba8d77246f
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
2025-01-14 10:02:00 +00:00
Arvind Ram Prakash
f99a69c386 feat(dsu): save/restore DSU PMU register
Adds driver support to preserve DSU PMU register values over a DSU
power cycle. This driver needs to be enabled by the platforms that
support DSU and also need it's PMU registers to be preserved

Change-Id: I7fc68a3d7d99ee369379aa5cd114fffc763fc0d2
Signed-off-by: Arvind Ram Prakash <arvind.ramprakash@arm.com>
2024-05-09 10:20:32 -05:00
David Vincze
33f29b8ae4 refactor(sds): modify log level for region validity
Modify the log level from WARNING to VERBOSE for the SDS region
validity check. An invalid region causes the initialization step
to fail, but normally it's only a temporary condition as the
actual initialization of the region (such as adding a valid region
descriptor structure) can happen asynchronously in another system
component. The goal of this tiny modification is to avoid flooding
the log with this message when we're waiting in a loop for the
region initialization to happen.

Change-Id: I180e35e25df3f31bbc816e6421ded17ba6ae1d85
Signed-off-by: David Vincze <david.vincze@arm.com>
2024-03-06 17:11:11 +01:00
Tamas Ban
8d1a04bd37 refactor(css): support multiple SDS regions
Extend the SDS driver to be able to handle multiple
SDS regions:
 - AP-SCP
 - AP-RSS

Change-Id: Id303840b248c383b3f960227cbf6333d1cc75e65
Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Signed-off-by: David Vincze <david.vincze@arm.com>
2024-02-13 14:36:14 +01:00
Pranav Madhu
af1ac2d7db fix(scmi): induce a delay in monitoring SCMI channel status
Reading the SCMI mailbox status in polling mode causes a burst of bus
accesses. On certain platforms, this would not be ideal as the shared
bus on the CPU subsystem might cause contentions across all the CPUs.
So allow platforms to specify a delay to be introduced while polling.

Change-Id: Ib90ad7b5954854071cfd543f4a27a178dde3d5c6
Signed-off-by: Pranav Madhu <pranav.madhu@arm.com>
2024-02-02 17:14:27 +05:30
Elyes Haouas
1b491eead5 fix(tree): correct some typos
found using codespell (https://github.com/codespell-project/codespell).

Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Change-Id: I1bfa797e3460adddeefa916bb68e22beddaf6373
2023-05-09 15:57:12 +01:00
Elyes Haouas
af4d8c6d50 fix: remove useless "return" at void functions
void functions() returns nothing. So remove useless "return".

found using checkpatch.pl[1]

[1]: https://review.coreboot.org/plugins/gitiles/coreboot/+/refs/heads/master/util/lint/checkpatch.pl

Change-Id: I3daab2abec225a657af48f7d8c215cc554713074
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
2023-02-16 15:15:30 +02:00
Pranav Madhu
14a2892309 feat(scmi): send powerdown request to online secondary cpus
To initiate a reset or reboot, the nonsecure OS invokes the PSCI
SYSTEM_RESET function from any one core. As per the PSCI specification,
it is the responsibility of firmware to implement the system view of
the reset or reboot operation. For the platforms supported by CSS,
trigger the reset/reboot operation by sending an SGI to rest all CPUs
which are online. The CPUs respond to this interrupt by initiating its
powerdown sequence.

In addition to these changes, fix coding style issues that are not
directly related to the code being introduced in this patch.

Change-Id: I547253ee28ef7eefa78180d016893671a406bbfa
Signed-off-by: Pranav Madhu <pranav.madhu@arm.com>
2022-09-15 18:09:56 +05:30
Pranav Madhu
5cf9cc130a feat(scmi): set warm reboot entry point
Before issuing the system power down command, set the trusted mailbox
to 0. This will ensure that in the case of a warm/cold reset, the
primary CPU executes from the cold boot sequence, clearing any stale
jump address at this location.

Change-Id: I491ef5baf7a6728acd7e90e4558939ba77b8f9bf
Signed-off-by: Pranav Madhu <pranav.madhu@arm.com>
2022-09-15 18:09:56 +05:30
sah01
99477f051e fix(scmi): make msg_header variable volatile
When tf-a is built with the llvm toolchain, the compiler optimizes the
variable in some way which results in SCMI_MSG_GET_TOKEN assert failure
in multiple places. This patch makes the msg_header variable in
mailbox_mem struct volatile, which seems to fix the issue.

Signed-off-by: sahil <sahil@arm.com>
Change-Id: I1d28b30a6472fc23ed85adff9cf73dfb536e39cc
2021-12-08 21:00:45 +05:30
Andre Przywara
e0baae7316 fix(scmi): mention "SCMI" in driver initialisation message
Currently the SCMI driver reports:
INFO:    Initializing driver on Channel 0
on the console, which is not very specific (which driver?).

Add "SCMI" to the message so the user knows what the firmware is trying
to initialise.

Change-Id: Id8202655d07b8e12fe07670d462c6202e6eae2f0
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2021-10-19 10:58:32 +02:00
Heyi Guo
05579daf79 style(scmi_common): add \n to warning messages
Add newline(\n) to make the message clearer when the warnings are
really triggered.

Signed-off-by: Heyi Guo <guoheyi@linux.alibaba.com>
Change-Id: I5e2574a52c9065db32ecb4d453b9b02445f69a82
2021-06-08 20:10:35 +08:00
Manish V Badarkhe
04e06973e1 fconf: Clean confused naming between TB_FW and FW_CONFIG
Cleaned up confused naming between TB_FW and FW_CONFIG.

Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: I9e9f6e6ca076d38fee0388f97d370431ae067f08
2020-06-24 08:44:26 +01:00
Manish Pandey
cc7f89de5a driver/arm/css: minor bug fix
The cpu index was wrongly checked causing it to assert always.
Since this code path is exercised only during TF test "NODE_HW_STAT",
which queries Power state from SCP, this bug was not detected earlier.

Change-Id: Ia25cef4c0aa23ed08092df39134937a2601c21ac
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
2020-03-05 18:03:53 +00:00
Samuel Holland
98367c8061 arm/css/scpi: Don't panic if the SCP fails to respond
Instead, pass back the error to the calling function. This allows
platform code to fall back to another PSCI implementation if
scpi_wait_ready() or a later SCPI command fails.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Change-Id: Ib4411e63c2512857f09ffffe1c405358dddeb4a6
2020-02-12 21:16:46 -06:00
Aditya Angadi
31e703f995 drivers/arm/scmi: allow use of multiple SCMI channels
On systems that have multiple platform components that can interpret the
SCMI messages, there is a need to support multiple SCMI channels (one
each to those platform components). Extend the existing SCMI interface
that currently supports only a single SCMI channel to support multiple
SCMI channels.

Change-Id: Ice4062475b903aef3b5e5bc37df364c9778a62c5
Signed-off-by: Aditya Angadi <aditya.angadi@arm.com>
2020-02-07 19:24:17 +05:30
Aditya Angadi
f893160690 drivers/mhu: derive doorbell base address
In order to allow the MHUv2 driver to be usable with multiple MHUv2
controllers, use the base address of the controller from the platform
information instead of the MHUV2_BASE_ADDR macro.

Change-Id: I4dbab87b929fb0568935e6c8b339ce67937f8cd1
Signed-off-by: Aditya Angadi <aditya.angadi@arm.com>
2020-02-07 19:24:17 +05:30
Deepika Bhavnani
5b33ad174a Unify type of "cpu_idx" across PSCI module.
NOTE for platform integrators:
   API `plat_psci_stat_get_residency()` third argument
   `last_cpu_idx` is changed from "signed int" to the
   "unsigned int" type.

Issue / Trouble points
1. cpu_idx is used as mix of `unsigned int` and `signed int` in code
with typecasting at some places leading to coverity issues.

2. Underlying platform API's return cpu_idx as `unsigned int`
and comparison is performed with platform specific defines
`PLAFORM_xxx` which is not consistent

Misra Rule 10.4:
The value of a complex expression of integer type may only be cast to
a type that is narrower and of the same signedness as the underlying
type of the expression.

Based on above points, cpu_idx is kept as `unsigned int` to match
the API's and low-level functions and platform defines are updated
where ever required

Signed-off-by: Deepika Bhavnani <deepika.bhavnani@arm.com>
Change-Id: Ib26fd16e420c35527204b126b9b91e8babcc3a5c
2020-01-10 17:11:51 +00:00
Julius Werner
d5dfdeb65f Replace __ASSEMBLY__ with compiler-builtin __ASSEMBLER__
NOTE: __ASSEMBLY__ macro is now deprecated in favor of __ASSEMBLER__.

All common C compilers predefine a macro called __ASSEMBLER__ when
preprocessing a .S file. There is no reason for TF-A to define it's own
__ASSEMBLY__ macro for this purpose instead. To unify code with the
export headers (which use __ASSEMBLER__ to avoid one extra dependency),
let's deprecate __ASSEMBLY__ and switch the code base over to the
predefined standard.

Change-Id: Id7d0ec8cf330195da80499c68562b65cb5ab7417
Signed-off-by: Julius Werner <jwerner@chromium.org>
2019-08-01 13:14:12 -07:00
Masahisa Kojima
292bc55193 drivers: scmi: scmi_sq: Modify wrong payload length
Payload length of the get dram mapping information message is 0.
The mbx_mem->len parameter should be 4, it only contains
message header.

Fixes: b67d202 ("plat/synquacer: enable SCMI support")
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Change-Id: If1cd4c855da2dc5dc4b6da3bea152b8441971de7
2019-05-23 14:41:35 +09:00
Ambroise Vincent
bde2836fcc Remove several warnings reported with W=2
Improved support for W=2 compilation flag by solving some nested-extern
and sign-compare warnings.

The libraries are compiling with warnings (which turn into errors with
the Werror flag).

Outside of libraries, some warnings cannot be fixed.

Change-Id: I06b1923857f2a6a50e93d62d0274915b268cef05
Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>
2019-04-01 10:43:42 +01:00
Masahisa Kojima
b67d20297f plat/synquacer: enable SCMI support
Enable the SCMI protocol support in SynQuacer platform.
Aside from power domain, system power and apcore management protocol,
this commit adds the vendor specific protocol(0x80).
This vendor specific protocol is used to get the dram mapping information
from SCP.

Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
2019-03-13 09:54:15 +09:00
Antonio Nino Diaz
73308618fe Minor changes to documentation and comments
Fix some typos and clarify some sentences.

Change-Id: Id276d1ced9a991b4eddc5c47ad9a825e6b29ef74
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-02-28 13:35:21 +00:00
Antonio Nino Diaz
5932d194d7 plat/arm: sds: Move to drivers/ folder
Change-Id: Ia601d5ad65ab199e747fb60af4979b7db477d249
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-01-25 16:04:11 +00:00
Antonio Nino Diaz
2d4135e08f plat/arm: scp: Move to drivers/ folder
Change-Id: Ida5dae39478654405d0ee31a6cbddb4579e76a7f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-01-25 16:04:11 +00:00
Antonio Nino Diaz
0387aa42ac plat/arm: scpi: Move to drivers/ folder
Change-Id: Icc59cdaf2b56f6936e9847f1894594c671db2e94
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-01-25 16:04:11 +00:00
Antonio Nino Diaz
c411396e55 plat/arm: mhu: Move to drivers/ folder
Change-Id: I656753a1825ea7340a3708b950fa6b57455e9056
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-01-25 16:04:11 +00:00
Antonio Nino Diaz
14928b88ab plat/arm: scmi: Move to drivers/ folder
Change-Id: I8989d2aa0258bf3b50a856c5b81532d578600124
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
2019-01-25 16:04:11 +00:00