x86/hpet: Add mode information to struct hpet_channel

The usage of the individual HPET channels is not tracked in a central
place. The information is scattered in different data structures. Also the
HPET reservation in the HPET character device is split out into several
places which makes the code hard to follow.

Assigning a mode to the channel allows to consolidate the reservation code
and paves the way for further simplifications.

As a first step set the mode of the legacy channels when the HPET is in
legacy mode.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Link: https://lkml.kernel.org/r/20190623132435.911652981@linutronix.de

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index 8711f1fdef8f2a7831663b7d75082fa8c6c7c9ab..3a8ec363d5694fc864ac01e46c28a313b3d72359 100644 (file)
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -22,9 +22,17 @@ struct hpet_dev {
        char                            name[10];
 };
 
+enum hpet_mode {
+       HPET_MODE_UNUSED,
+       HPET_MODE_LEGACY,
+       HPET_MODE_CLOCKEVT,
+       HPET_MODE_DEVICE,
+};
+
 struct hpet_channel {
        unsigned int                    num;
        unsigned int                    irq;
+       enum hpet_mode                  mode;
        unsigned int                    boot_cfg;
 };
 
@@ -947,6 +955,9 @@ int __init hpet_enable(void)
 
        if (id & HPET_ID_LEGSUP) {
                hpet_legacy_clockevent_register();
+               hpet_base.channels[0].mode = HPET_MODE_LEGACY;
+               if (IS_ENABLED(CONFIG_HPET_EMULATE_RTC))
+                       hpet_base.channels[1].mode = HPET_MODE_LEGACY;
                return 1;
        }
        return 0;