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authorLinus Torvalds <torvalds@linux-foundation.org>2020-03-31 10:05:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-03-31 10:05:01 -0700
commit3cd86a58f7734bf9cef38f6f899608ebcaa3da13 (patch)
tree6ae5b8109011ee40deef645a9701e2d8dc4e4fce /drivers/clocksource/arm_arch_timer.c
parenta8222fd5b80c7ec83f257060670becbeea9b50b9 (diff)
parentb2a84de2a2deb76a6a51609845341f508c518c03 (diff)
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas: "The bulk is in-kernel pointer authentication, activity monitors and lots of asm symbol annotations. I also queued the sys_mremap() patch commenting the asymmetry in the address untagging. Summary: - In-kernel Pointer Authentication support (previously only offered to user space). - ARM Activity Monitors (AMU) extension support allowing better CPU utilisation numbers for the scheduler (frequency invariance). - Memory hot-remove support for arm64. - Lots of asm annotations (SYM_*) in preparation for the in-kernel Branch Target Identification (BTI) support. - arm64 perf updates: ARMv8.5-PMU 64-bit counters, refactoring the PMU init callbacks, support for new DT compatibles. - IPv6 header checksum optimisation. - Fixes: SDEI (software delegated exception interface) double-lock on hibernate with shared events. - Minor clean-ups and refactoring: cpu_ops accessor, cpu_do_switch_mm() converted to C, cpufeature finalisation helper. - sys_mremap() comment explaining the asymmetric address untagging behaviour" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (81 commits) mm/mremap: Add comment explaining the untagging behaviour of mremap() arm64: head: Convert install_el2_stub to SYM_INNER_LABEL arm64: Introduce get_cpu_ops() helper function arm64: Rename cpu_read_ops() to init_cpu_ops() arm64: Declare ACPI parking protocol CPU operation if needed arm64: move kimage_vaddr to .rodata arm64: use mov_q instead of literal ldr arm64: Kconfig: verify binutils support for ARM64_PTR_AUTH lkdtm: arm64: test kernel pointer authentication arm64: compile the kernel with ptrauth return address signing kconfig: Add support for 'as-option' arm64: suspend: restore the kernel ptrauth keys arm64: __show_regs: strip PAC from lr in printk arm64: unwind: strip PAC from kernel addresses arm64: mask PAC bits of __builtin_return_address arm64: initialize ptrauth keys for kernel booting task arm64: initialize and switch ptrauth kernel keys arm64: enable ptrauth earlier arm64: cpufeature: handle conflicts based on capability arm64: cpufeature: Move cpu capability helpers inside C file ...
Diffstat (limited to 'drivers/clocksource/arm_arch_timer.c')
-rw-r--r--drivers/clocksource/arm_arch_timer.c18
1 files changed, 15 insertions, 3 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index d53f4c7ccaae..2204a444e801 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -889,6 +889,17 @@ static int arch_timer_starting_cpu(unsigned int cpu)
return 0;
}
+static int validate_timer_rate(void)
+{
+ if (!arch_timer_rate)
+ return -EINVAL;
+
+ /* Arch timer frequency < 1MHz can cause trouble */
+ WARN_ON(arch_timer_rate < 1000000);
+
+ return 0;
+}
+
/*
* For historical reasons, when probing with DT we use whichever (non-zero)
* rate was probed first, and don't verify that others match. If the first node
@@ -904,7 +915,7 @@ static void arch_timer_of_configure_rate(u32 rate, struct device_node *np)
arch_timer_rate = rate;
/* Check the timer frequency. */
- if (arch_timer_rate == 0)
+ if (validate_timer_rate())
pr_warn("frequency not available\n");
}
@@ -1598,9 +1609,10 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
* CNTFRQ value. This *must* be correct.
*/
arch_timer_rate = arch_timer_get_cntfrq();
- if (!arch_timer_rate) {
+ ret = validate_timer_rate();
+ if (ret) {
pr_err(FW_BUG "frequency not available.\n");
- return -EINVAL;
+ return ret;
}
arch_timer_uses_ppi = arch_timer_select_ppi();