| Message ID | 1419239097-14758-3-git-send-email-pranavkumar@linaro.org |
|---|---|
| State | New |
| Headers | show |
On 22 December 2014 at 09:04, Pranavkumar Sawargaonkar <pranavkumar@linaro.org> wrote: > This patch implements a fucntion pointer virtio_is_big_endian() > from "CPUClass" structure for arm/arm64. > Function arm_cpu_virtio_endianness() is added to determine and > return the guest cpu endianness to virtio. > This is required for running cross endian guests with virtio on ARM/ARM64. > > Changelog: The changelog should go below the "---" line, ideally. > V2: > - Change the patch to be used generically for both ARM and ARM64. > - Address the review comments received in v1. > > V1: > - First patch in this series. > - http://lists.gnu.org/archive/html/qemu-devel/2014-10/msg03321.html > > Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> > --- > target-arm/cpu.c | 27 +++++++++++++++++++++++++++ > target-arm/cpu.h | 2 ++ > 2 files changed, 29 insertions(+) > > diff --git a/target-arm/cpu.c b/target-arm/cpu.c > index d3db279..7145e02 100644 > --- a/target-arm/cpu.c > +++ b/target-arm/cpu.c > @@ -320,6 +320,32 @@ static void arm_cpu_kvm_set_irq(void *opaque, int irq, int level) > kvm_set_irq(kvm_state, kvm_irq, level ? 1 : 0); > #endif > } > + > +static bool arm_cpu_virtio_endianness(CPUState *cs) You should call this arm_cpu_is_big_endian(), which lines up with the PPC function name and is closer to the QOM method name we're implementing. > +{ > + ARMCPU *cpu = ARM_CPU(cs); > + CPUARMState *env = &cpu->env; > + uint64_t sctlr; > + > + cpu_synchronize_state(cs); > + > + /* Check if we are running 32bit guest or not */ I don't think this comment is particularly informative. > + if (!is_a64(env)) { > + return (env->pstate & CPSR_E) ? 1 : 0; > + } > + > + sctlr = env->cp15.sctlr_el[1]; > + > + if ((env->pstate & 0xf) == PSTATE_MODE_EL0t) { > + sctlr &= SCTLR_E0E; > + } else { > + sctlr &= SCTLR_EE; > + } We might as well make this robust for when we implement EL2 and EL3: int cur_el; ... cur_el = arm_current_el(env); if (cur_el == 0) { return (env->cp15.sctlr_el[1] & SCTLR_E0E) != 0; } else { return (env->cp15.sctlr_el[cur_el] & SCTLR_EE) != 0; } > + > + /* If BIG-ENDIAN return 1 */ ...and with the new function name this comment isn't necessary either, because it's obvious. > + return sctlr ? 1 : 0; > +} > + > #endif > > static inline void set_feature(CPUARMState *env, int feature) > @@ -1157,6 +1183,7 @@ static void arm_cpu_class_init(ObjectClass *oc, void *data) > cc->do_interrupt = arm_cpu_do_interrupt; > cc->get_phys_page_debug = arm_cpu_get_phys_page_debug; > cc->vmsd = &vmstate_arm_cpu; > + cc->virtio_is_big_endian = arm_cpu_virtio_endianness; > #endif > cc->gdb_num_core_regs = 26; > cc->gdb_core_xml_file = "arm-core.xml"; > diff --git a/target-arm/cpu.h b/target-arm/cpu.h > index 7ba55f0..f32a5b6 100644 > --- a/target-arm/cpu.h > +++ b/target-arm/cpu.h > @@ -32,6 +32,8 @@ > # define ELF_MACHINE EM_ARM > #endif > > +#define TARGET_IS_BIENDIAN 1 > + > #define CPUArchState struct CPUARMState > > #include "qemu-common.h" > -- > 1.9.1 thanks -- PMM
diff --git a/target-arm/cpu.c b/target-arm/cpu.c index d3db279..7145e02 100644 --- a/target-arm/cpu.c +++ b/target-arm/cpu.c @@ -320,6 +320,32 @@ static void arm_cpu_kvm_set_irq(void *opaque, int irq, int level) kvm_set_irq(kvm_state, kvm_irq, level ? 1 : 0); #endif } + +static bool arm_cpu_virtio_endianness(CPUState *cs) +{ + ARMCPU *cpu = ARM_CPU(cs); + CPUARMState *env = &cpu->env; + uint64_t sctlr; + + cpu_synchronize_state(cs); + + /* Check if we are running 32bit guest or not */ + if (!is_a64(env)) { + return (env->pstate & CPSR_E) ? 1 : 0; + } + + sctlr = env->cp15.sctlr_el[1]; + + if ((env->pstate & 0xf) == PSTATE_MODE_EL0t) { + sctlr &= SCTLR_E0E; + } else { + sctlr &= SCTLR_EE; + } + + /* If BIG-ENDIAN return 1 */ + return sctlr ? 1 : 0; +} + #endif static inline void set_feature(CPUARMState *env, int feature) @@ -1157,6 +1183,7 @@ static void arm_cpu_class_init(ObjectClass *oc, void *data) cc->do_interrupt = arm_cpu_do_interrupt; cc->get_phys_page_debug = arm_cpu_get_phys_page_debug; cc->vmsd = &vmstate_arm_cpu; + cc->virtio_is_big_endian = arm_cpu_virtio_endianness; #endif cc->gdb_num_core_regs = 26; cc->gdb_core_xml_file = "arm-core.xml"; diff --git a/target-arm/cpu.h b/target-arm/cpu.h index 7ba55f0..f32a5b6 100644 --- a/target-arm/cpu.h +++ b/target-arm/cpu.h @@ -32,6 +32,8 @@ # define ELF_MACHINE EM_ARM #endif +#define TARGET_IS_BIENDIAN 1 + #define CPUArchState struct CPUARMState #include "qemu-common.h"
This patch implements a fucntion pointer virtio_is_big_endian() from "CPUClass" structure for arm/arm64. Function arm_cpu_virtio_endianness() is added to determine and return the guest cpu endianness to virtio. This is required for running cross endian guests with virtio on ARM/ARM64. Changelog: V2: - Change the patch to be used generically for both ARM and ARM64. - Address the review comments received in v1. V1: - First patch in this series. - http://lists.gnu.org/archive/html/qemu-devel/2014-10/msg03321.html Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> --- target-arm/cpu.c | 27 +++++++++++++++++++++++++++ target-arm/cpu.h | 2 ++ 2 files changed, 29 insertions(+)