qemu/target/openrisc
Stafford Horne f4d1414a93 target/openrisc: Support non-busy idle state using PMR SPR
The OpenRISC architecture has the Power Management Register (PMR)
special purpose register to manage cpu power states.  The interesting
modes are:

 * Doze Mode (DME) - Stop cpu except timer & pic - wake on interrupt
 * Sleep Mode (SME) - Stop cpu and all units - wake on interrupt
 * Suspend Model (SUME) - Stop cpu and all units - wake on reset

The linux kernel will set DME when idle.

This patch implements the PMR SPR and halts the qemu cpu when there is a
change to DME or SME.  This means that openrisc qemu in no longer peggs
a host cpu at 100%.

In order for this to work we need to kick the CPU when timers are
expired.  Update the cpu timer to kick the cpu upon each timer event.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-05-04 09:39:14 +09:00
..
Makefile.objs target/openrisc: Streamline arithmetic and OVE 2017-02-14 08:14:59 +11:00
cpu.c target/openrisc: Support non-busy idle state using PMR SPR 2017-05-04 09:39:14 +09:00
cpu.h target/openrisc: Support non-busy idle state using PMR SPR 2017-05-04 09:39:14 +09:00
exception.c Move target-* CPU file into a target/ folder 2016-12-20 21:52:12 +01:00
exception.h Move target-* CPU file into a target/ folder 2016-12-20 21:52:12 +01:00
exception_helper.c target/openrisc: Optimize for r0 being zero 2017-02-14 08:15:00 +11:00
fpu_helper.c target/openrisc: Fix madd 2017-02-14 08:15:00 +11:00
gdbstub.c target/openrisc: implement shadow registers 2017-05-04 09:39:01 +09:00
helper.h target/openrisc: Fix madd 2017-02-14 08:15:00 +11:00
interrupt.c target/openrisc: Support non-busy idle state using PMR SPR 2017-05-04 09:39:14 +09:00
interrupt_helper.c target/openrisc: Tidy ppc/npc implementation 2017-02-14 08:15:00 +11:00
machine.c target/openrisc: Support non-busy idle state using PMR SPR 2017-05-04 09:39:14 +09:00
mmu.c target/openrisc: Fixes for memory debugging 2017-05-04 09:38:49 +09:00
mmu_helper.c Move target-* CPU file into a target/ folder 2016-12-20 21:52:12 +01:00
sys_helper.c target/openrisc: Support non-busy idle state using PMR SPR 2017-05-04 09:39:14 +09:00
translate.c target/openrisc: implement shadow registers 2017-05-04 09:39:01 +09:00