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path: root/target/openrisc/cpu.c
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2017-05-04target/openrisc: Support non-busy idle state using PMR SPRStafford Horne
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>
2017-05-04target/openrisc: Remove duplicate features propertyStafford Horne
The features property has stored the exact same thing as the cpucfgr spr. Remove the feature enum and property as it is not needed. In order to preserve the behavior or keeping features accross reset this patch moves cpucfgr into the non reset region of the state struct. Since the cpucfgr is read only this means we only need to sset cpucfgr once during class init. Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-05-04target/openrisc: implement shadow registersStafford Horne
Shadow registers are part of the openrisc spec along with sr[cid], as part of the fast context switching feature. When exceptions occur, instead of having to save registers to the stack if enabled the CID will increment and a new set of registers will be available. This patch only implements shadow registers which can be used as extra scratch registers via the mfspr and mtspr if required. This is implemented in a way where it would be easy to add on the fast context switching, currently cid is hardcoded to 0. This is need for openrisc linux smp kernels to boot correctly. Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-04-21target/openrisc: Implement EVBAR registerTim 'mithro' Ansell
Exception Vector Base Address Register (EVBAR) - This optional register can be used to apply an offset to the exception vector addresses. The significant bits (31-12) of the vector offset address for each exception depend on the setting of the Supervision Register (SR)'s EPH bit and the Exception Vector Base Address Register (EVBAR). Its presence is indicated by the EVBARP bit in the CPU Configuration Register (CPUCFGR). Signed-off-by: Tim 'mithro' Ansell <mithro@mithis.com> Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-02-14target/openrisc: Implement lwa, swaRichard Henderson
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-13qom/cpu: move tlb_flush to cpu_common_resetAlex Bennée
It is a common thing amongst the various cpu reset functions want to flush the SoftMMU's TLB entries. This is done either by calling tlb_flush directly or by way of a general memset of the CPU structure (sometimes both). This moves the tlb_flush call to the common reset function and additionally ensures it is only done for the CONFIG_SOFTMMU case and when tcg is enabled. In some target cases we add an empty end_of_reset_fields structure to the target vCPU structure so have a clear end point for any memset which is resetting value in the structure before CPU_COMMON (where the TLB structures are). While this is a nice clean-up in general it is also a precursor for changes coming to cputlb for MTTCG where the clearing of entries can't be done arbitrarily across vCPUs. Currently the cpu_reset function is usually called from the context of another vCPU as the architectural power up sequence is run. By using the cputlb API functions we can ensure the right behaviour in the future. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2016-12-20Move target-* CPU file into a target/ folderThomas Huth
We've currently got 18 architectures in QEMU, and thus 18 target-xxx folders in the root folder of the QEMU source tree. More architectures (e.g. RISC-V, AVR) are likely to be included soon, too, so the main folder of the QEMU sources slowly gets quite overcrowded with the target-xxx folders. To disburden the main folder a little bit, let's move the target-xxx folders into a dedicated target/ folder, so that target-xxx/ simply becomes target/xxx/ instead. Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part] Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part] Acked-by: Michael Walle <michael@walle.cc> [lm32 part] Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part] Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part] Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part] Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part] Acked-by: Richard Henderson <rth@twiddle.net> [alpha part] Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part] Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part] Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [cris&microblaze part] Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part] Signed-off-by: Thomas Huth <thuth@redhat.com>