[PATCH v19 05/15] clocksource/drivers/arm_arch_timer: rework PPI determination
From: mark.rutland@arm.com (Mark Rutland)
Date: 2017-01-16 17:30:59
Also in:
linux-acpi, linux-watchdog, lkml
On Wed, Dec 21, 2016 at 02:45:53PM +0800, fu.wei at linaro.org wrote: [...]
- if (is_hyp_mode_available() || !arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) {
- bool has_ppi;
+ if (is_hyp_mode_available() && is_kernel_in_hyp_mode())
+ return ARCH_TIMER_HYP_PPI;
- if (is_kernel_in_hyp_mode()) {
- arch_timer_uses_ppi = ARCH_TIMER_HYP_PPI;
- has_ppi = !!arch_timer_ppi[ARCH_TIMER_HYP_PPI];
- } else {
- arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
- has_ppi = (!!arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI] ||
- !!arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
- }
+ if (arch_timer_ppi[ARCH_TIMER_VIRT_PPI])
+ return ARCH_TIMER_VIRT_PPI;
- if (!has_ppi) {
- pr_warn("No interrupt available, giving up\n");
- return -EINVAL;
- }
- }
+ if (IS_ENABLED(CONFIG_ARM64))
+ return ARCH_TIMER_PHYS_NONSECURE_PPI;
+
+ return ARCH_TIMER_PHYS_SECURE_PPI;For a 32-bit platform booted at hyp (with a virt PPI available), the new logic will select ARCH_TIMER_VIRT_PPI. I beleive that will break KVM. I think the logic should be: if (is_kernel_in_hyp_mode()) return ARCH_TIMER_HYP_PPI; if (!is_hyp_mode_available() && arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) return ARCH_TIMER_VIRT_PPI; if (IS_ENABLED(CONFIG_ARM64)) return ARCH_TIMER_PHYS_NONSECURE_PPI; return ARCH_TIMER_PHYS_SECURE_PPI; Please use that instead (keeping the comment you retained).
quoted hunk ↗ jump to hunk
+static int __init arch_timer_init(void) +{ + int ret; ret = arch_timer_register(); if (ret)@@ -904,6 +906,13 @@ static int __init arch_timer_of_init(struct device_node *np) if (IS_ENABLED(CONFIG_ARM) && of_property_read_bool(np, "arm,cpu-registers-not-fw-configured")) arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI; + else + arch_timer_uses_ppi = arch_timer_select_ppi(); + + if (!arch_timer_ppi[arch_timer_uses_ppi]) { + pr_err("No interrupt available, giving up\n"); + return -EINVAL; + } /* On some systems, the counter stops ticking when in suspend. */ arch_counter_suspend_stop = of_property_read_bool(np,@@ -1049,6 +1058,12 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table) /* Get the frequency from CNTFRQ */ arch_timer_detect_rate(NULL, NULL); + arch_timer_uses_ppi = arch_timer_select_ppi(); + if (!arch_timer_ppi[arch_timer_uses_ppi]) { + pr_err("No interrupt available, giving up\n"); + return -EINVAL; + }
I see that we have to duplicate this so we can special-case the DT-specific behaviour, so that's fine by me. If you can fix the arch_timer_select_ppi() logic as above, this should be fine. Thanks, Mark.