Message ID | 1327498343-5830-2-git-send-email-peter.maydell@linaro.org |
---|---|
State | Accepted |
Commit | 0383ac006f6bfa60d5cb3d0ddf4a9e1d65f9c900 |
Headers | show |
Am 25.01.2012 14:32, schrieb Peter Maydell: > Add a dummy implementation of the cp15 registers for the generic > timer (found in the Cortex-A15), just sufficient for Linux to > decide that it can't use it. This requires at least CNTP_CTL and > CNTFRQ to be implemented as RAZ/WI; we RAZ/WI all of c14. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Andreas Färber <afaerber@suse.de> Took me a bit to figure out RAZ/WI. ;) Andreas > --- > target-arm/cpu.h | 1 + > target-arm/helper.c | 12 ++++++++++-- > 2 files changed, 11 insertions(+), 2 deletions(-) > > diff --git a/target-arm/cpu.h b/target-arm/cpu.h > index 42c53a7..7442c99 100644 > --- a/target-arm/cpu.h > +++ b/target-arm/cpu.h > @@ -382,6 +382,7 @@ enum arm_features { > ARM_FEATURE_VAPA, /* cp15 VA to PA lookups */ > ARM_FEATURE_ARM_DIV, /* divide supported in ARM encoding */ > ARM_FEATURE_VFP4, /* VFPv4 (implies that NEON is v2) */ > + ARM_FEATURE_GENERIC_TIMER, > }; > > static inline int arm_feature(CPUARMState *env, int feature) > diff --git a/target-arm/helper.c b/target-arm/helper.c > index 22e40fc..5e7205a 100644 > --- a/target-arm/helper.c > +++ b/target-arm/helper.c > @@ -1764,7 +1764,11 @@ void HELPER(set_cp15)(CPUState *env, uint32_t insn, uint32_t val) > goto bad_reg; > } > break; > - case 14: /* Reserved. */ > + case 14: /* Generic timer */ > + if (arm_feature(env, ARM_FEATURE_GENERIC_TIMER)) { > + /* Dummy implementation: RAZ/WI for all */ > + break; > + } > goto bad_reg; > case 15: /* Implementation specific. */ > if (arm_feature(env, ARM_FEATURE_XSCALE)) { > @@ -2134,7 +2138,11 @@ uint32_t HELPER(get_cp15)(CPUState *env, uint32_t insn) > default: > goto bad_reg; > } > - case 14: /* Reserved. */ > + case 14: /* Generic timer */ > + if (arm_feature(env, ARM_FEATURE_GENERIC_TIMER)) { > + /* Dummy implementation: RAZ/WI for all */ > + return 0; > + } > goto bad_reg; > case 15: /* Implementation specific. */ > if (arm_feature(env, ARM_FEATURE_XSCALE)) {
On 25 January 2012 14:01, Andreas Färber <afaerber@suse.de> wrote: > Am 25.01.2012 14:32, schrieb Peter Maydell: >> Add a dummy implementation of the cp15 registers for the generic >> timer (found in the Cortex-A15), just sufficient for Linux to >> decide that it can't use it. This requires at least CNTP_CTL and >> CNTFRQ to be implemented as RAZ/WI; we RAZ/WI all of c14. >> >> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > > Reviewed-by: Andreas Färber <afaerber@suse.de> > > Took me a bit to figure out RAZ/WI. ;) Sorry, that's ARM ARM jargon :-) (Read As Zero/Writes Ignored, for anybody still baffled.) -- PMM
diff --git a/target-arm/cpu.h b/target-arm/cpu.h index 42c53a7..7442c99 100644 --- a/target-arm/cpu.h +++ b/target-arm/cpu.h @@ -382,6 +382,7 @@ enum arm_features { ARM_FEATURE_VAPA, /* cp15 VA to PA lookups */ ARM_FEATURE_ARM_DIV, /* divide supported in ARM encoding */ ARM_FEATURE_VFP4, /* VFPv4 (implies that NEON is v2) */ + ARM_FEATURE_GENERIC_TIMER, }; static inline int arm_feature(CPUARMState *env, int feature) diff --git a/target-arm/helper.c b/target-arm/helper.c index 22e40fc..5e7205a 100644 --- a/target-arm/helper.c +++ b/target-arm/helper.c @@ -1764,7 +1764,11 @@ void HELPER(set_cp15)(CPUState *env, uint32_t insn, uint32_t val) goto bad_reg; } break; - case 14: /* Reserved. */ + case 14: /* Generic timer */ + if (arm_feature(env, ARM_FEATURE_GENERIC_TIMER)) { + /* Dummy implementation: RAZ/WI for all */ + break; + } goto bad_reg; case 15: /* Implementation specific. */ if (arm_feature(env, ARM_FEATURE_XSCALE)) { @@ -2134,7 +2138,11 @@ uint32_t HELPER(get_cp15)(CPUState *env, uint32_t insn) default: goto bad_reg; } - case 14: /* Reserved. */ + case 14: /* Generic timer */ + if (arm_feature(env, ARM_FEATURE_GENERIC_TIMER)) { + /* Dummy implementation: RAZ/WI for all */ + return 0; + } goto bad_reg; case 15: /* Implementation specific. */ if (arm_feature(env, ARM_FEATURE_XSCALE)) {
Add a dummy implementation of the cp15 registers for the generic timer (found in the Cortex-A15), just sufficient for Linux to decide that it can't use it. This requires at least CNTP_CTL and CNTFRQ to be implemented as RAZ/WI; we RAZ/WI all of c14. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- target-arm/cpu.h | 1 + target-arm/helper.c | 12 ++++++++++-- 2 files changed, 11 insertions(+), 2 deletions(-)