diff options
author | Jean-Philippe Brucker <jean-philippe@linaro.org> | 2021-05-07 12:20:23 +0200 |
---|---|---|
committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2024-01-08 12:37:56 +0000 |
commit | b0fd81597fa8851a7eef2f88bb39ff3ccd5d3e45 (patch) | |
tree | 59654c5854fdd21f925e0394197d49ec2254f7d9 /arch/arm64/kernel/psci.c | |
parent | a369d7f2ce84ffe77c4ea7bb22fd6df94e5878b5 (diff) |
arm64: psci: Ignore DENIED CPUs
When a CPU is marked as disabled, but online capable in the MADT, PSCI
applies some firmware policy to control when it can be brought online.
PSCI returns DENIED to a CPU_ON request if this is not currently
permitted. The OS can learn the current policy from the _STA enabled bit.
Handle the PSCI DENIED return code gracefully instead of printing an
error.
See https://developer.arm.com/documentation/den0022/f/?lang=en page 58.
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
[ morse: Rewrote commit message ]
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
Tested-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com>
Tested-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
Changes since RFC v2
* Add specification reference
* Use EPERM rather than EPROBE_DEFER
Changes since RFC v3:
* Use EPERM everywhere
* Drop unnecessary changes to drivers/firmware/psci/psci.c
Diffstat (limited to 'arch/arm64/kernel/psci.c')
-rw-r--r-- | arch/arm64/kernel/psci.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 29a8e444db83..fabd732d0a2d 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -40,7 +40,7 @@ static int cpu_psci_cpu_boot(unsigned int cpu) { phys_addr_t pa_secondary_entry = __pa_symbol(secondary_entry); int err = psci_ops.cpu_on(cpu_logical_map(cpu), pa_secondary_entry); - if (err) + if (err && err != -EPERM) pr_err("failed to boot CPU%d (%d)\n", cpu, err); return err; |