* [PATCH] xen: arm: vtimer fixes for arm64
@ 2013-12-05 12:58 Ian Campbell
2013-12-06 16:30 ` Julien Grall
2013-12-06 17:38 ` Stefano Stabellini
0 siblings, 2 replies; 6+ messages in thread
From: Ian Campbell @ 2013-12-05 12:58 UTC (permalink / raw)
To: xen-devel; +Cc: julien.grall, tim, Ian Campbell, stefano.stabellini
The code was writing back the register, even for writes and didn't implement
CNTPCT at all.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
xen/arch/arm/vtimer.c | 51 ++++++++++++++++++++++++++++++++++---------------
1 file changed, 36 insertions(+), 15 deletions(-)
diff --git a/xen/arch/arm/vtimer.c b/xen/arch/arm/vtimer.c
index f323453..dcda2b2 100644
--- a/xen/arch/arm/vtimer.c
+++ b/xen/arch/arm/vtimer.c
@@ -165,6 +165,27 @@ static void vtimer_cntp_tval(struct cpu_user_regs *regs, uint32_t *r, int read)
}
}
+static int vtimer_cntpct(struct cpu_user_regs *regs, uint64_t *r, int read)
+{
+ struct vcpu *v = current;
+ uint64_t ticks;
+ s_time_t now;
+
+ if ( read )
+ {
+ now = NOW() - v->domain->arch.phys_timer_base.offset;
+ ticks = ns_to_ticks(now);
+ *r = ticks;
+ return 1;
+ }
+ else
+ {
+ gdprintk(XENLOG_DEBUG, "READ from R/O CNTPCT\n");
+ return 0;
+ }
+}
+
+
static int vtimer_emulate_cp32(struct cpu_user_regs *regs, union hsr hsr)
{
struct hsr_cp32 cp32 = hsr.cp32;
@@ -187,29 +208,23 @@ static int vtimer_emulate_cp32(struct cpu_user_regs *regs, union hsr hsr)
static int vtimer_emulate_cp64(struct cpu_user_regs *regs, union hsr hsr)
{
- struct vcpu *v = current;
struct hsr_cp64 cp64 = hsr.cp64;
uint32_t *r1 = (uint32_t *)select_user_reg(regs, cp64.reg1);
uint32_t *r2 = (uint32_t *)select_user_reg(regs, cp64.reg2);
- uint64_t ticks;
- s_time_t now;
+ uint64_t x;
switch ( hsr.bits & HSR_CP64_REGS_MASK )
{
case HSR_CPREG64(CNTPCT):
+ if (!vtimer_cntpct(regs, &x, cp64.read))
+ return 0;
+
if ( cp64.read )
{
- now = NOW() - v->domain->arch.phys_timer_base.offset;
- ticks = ns_to_ticks(now);
- *r1 = (uint32_t)(ticks & 0xffffffff);
- *r2 = (uint32_t)(ticks >> 32);
- return 1;
- }
- else
- {
- printk("READ from R/O CNTPCT\n");
- return 0;
+ *r1 = (uint32_t)(x & 0xffffffff);
+ *r2 = (uint32_t)(x >> 32);
}
+ return 1;
default:
return 0;
@@ -227,12 +242,18 @@ static int vtimer_emulate_sysreg(struct cpu_user_regs *regs, union hsr hsr)
{
case CNTP_CTL_EL0:
vtimer_cntp_ctl(regs, &r, sysreg.read);
- *x = r;
+ if ( sysreg.read )
+ *x = r;
return 1;
case CNTP_TVAL_EL0:
vtimer_cntp_tval(regs, &r, sysreg.read);
- *x = r;
+ if ( sysreg.read )
+ *x = r;
return 1;
+
+ case HSR_CPREG64(CNTPCT):
+ return vtimer_cntpct(regs, x, sysreg.read);
+
default:
return 0;
}
--
1.7.10.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] xen: arm: vtimer fixes for arm64
2013-12-05 12:58 [PATCH] xen: arm: vtimer fixes for arm64 Ian Campbell
@ 2013-12-06 16:30 ` Julien Grall
2013-12-06 17:06 ` Ian Campbell
2013-12-06 17:38 ` Stefano Stabellini
1 sibling, 1 reply; 6+ messages in thread
From: Julien Grall @ 2013-12-06 16:30 UTC (permalink / raw)
To: Ian Campbell, xen-devel; +Cc: tim, stefano.stabellini
On 12/05/2013 12:58 PM, Ian Campbell wrote:
> The code was writing back the register, even for writes and didn't implement
> CNTPCT at all.
>
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> ---
> xen/arch/arm/vtimer.c | 51 ++++++++++++++++++++++++++++++++++---------------
> 1 file changed, 36 insertions(+), 15 deletions(-)
>
> diff --git a/xen/arch/arm/vtimer.c b/xen/arch/arm/vtimer.c
> index f323453..dcda2b2 100644
> --- a/xen/arch/arm/vtimer.c
> +++ b/xen/arch/arm/vtimer.c
> @@ -165,6 +165,27 @@ static void vtimer_cntp_tval(struct cpu_user_regs *regs, uint32_t *r, int read)
> }
> }
>
> +static int vtimer_cntpct(struct cpu_user_regs *regs, uint64_t *r, int read)
> +{
> + struct vcpu *v = current;
> + uint64_t ticks;
> + s_time_t now;
> +
> + if ( read )
> + {
> + now = NOW() - v->domain->arch.phys_timer_base.offset;
> + ticks = ns_to_ticks(now);
> + *r = ticks;
> + return 1;
> + }
> + else
> + {
> + gdprintk(XENLOG_DEBUG, "READ from R/O CNTPCT\n");
s/READ/WRITE/ ?
Except this minor typo:
Acked-by: Julien Grall <julien.grall@linaro.org>
--
Julien Grall
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] xen: arm: vtimer fixes for arm64
2013-12-06 16:30 ` Julien Grall
@ 2013-12-06 17:06 ` Ian Campbell
0 siblings, 0 replies; 6+ messages in thread
From: Ian Campbell @ 2013-12-06 17:06 UTC (permalink / raw)
To: Julien Grall; +Cc: stefano.stabellini, tim, xen-devel
On Fri, 2013-12-06 at 16:30 +0000, Julien Grall wrote:
>
> On 12/05/2013 12:58 PM, Ian Campbell wrote:
> > The code was writing back the register, even for writes and didn't implement
> > CNTPCT at all.
> >
> > Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> > ---
> > xen/arch/arm/vtimer.c | 51 ++++++++++++++++++++++++++++++++++---------------
> > 1 file changed, 36 insertions(+), 15 deletions(-)
> >
> > diff --git a/xen/arch/arm/vtimer.c b/xen/arch/arm/vtimer.c
> > index f323453..dcda2b2 100644
> > --- a/xen/arch/arm/vtimer.c
> > +++ b/xen/arch/arm/vtimer.c
> > @@ -165,6 +165,27 @@ static void vtimer_cntp_tval(struct cpu_user_regs *regs, uint32_t *r, int read)
> > }
> > }
> >
> > +static int vtimer_cntpct(struct cpu_user_regs *regs, uint64_t *r, int read)
> > +{
> > + struct vcpu *v = current;
> > + uint64_t ticks;
> > + s_time_t now;
> > +
> > + if ( read )
> > + {
> > + now = NOW() - v->domain->arch.phys_timer_base.offset;
> > + ticks = ns_to_ticks(now);
> > + *r = ticks;
> > + return 1;
> > + }
> > + else
> > + {
> > + gdprintk(XENLOG_DEBUG, "READ from R/O CNTPCT\n");
>
> s/READ/WRITE/ ?
Yeah, copied blindly from the existing wrong code!
> Except this minor typo:
>
> Acked-by: Julien Grall <julien.grall@linaro.org>
Thanks.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] xen: arm: vtimer fixes for arm64
2013-12-05 12:58 [PATCH] xen: arm: vtimer fixes for arm64 Ian Campbell
2013-12-06 16:30 ` Julien Grall
@ 2013-12-06 17:38 ` Stefano Stabellini
2013-12-06 17:42 ` Ian Campbell
1 sibling, 1 reply; 6+ messages in thread
From: Stefano Stabellini @ 2013-12-06 17:38 UTC (permalink / raw)
To: Ian Campbell; +Cc: stefano.stabellini, tim, julien.grall, xen-devel
On Thu, 5 Dec 2013, Ian Campbell wrote:
> @@ -227,12 +242,18 @@ static int vtimer_emulate_sysreg(struct cpu_user_regs *regs, union hsr hsr)
> {
> case CNTP_CTL_EL0:
> vtimer_cntp_ctl(regs, &r, sysreg.read);
> - *x = r;
> + if ( sysreg.read )
> + *x = r;
> return 1;
> case CNTP_TVAL_EL0:
> vtimer_cntp_tval(regs, &r, sysreg.read);
> - *x = r;
> + if ( sysreg.read )
> + *x = r;
> return 1;
Are you sure that sysreg.read == 1 means write?
>From xen/arch/arm/traps.c:do_sysreg:
printk("%s %d, %d, c%d, c%d, %d %s x%d @ 0x%"PRIregister"\n",
sysreg.read ? "mrs" : "msr",
sysreg.read == 1 -> mrs that is a read from special register.
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] xen: arm: vtimer fixes for arm64
2013-12-06 17:38 ` Stefano Stabellini
@ 2013-12-06 17:42 ` Ian Campbell
2013-12-06 17:49 ` Stefano Stabellini
0 siblings, 1 reply; 6+ messages in thread
From: Ian Campbell @ 2013-12-06 17:42 UTC (permalink / raw)
To: Stefano Stabellini; +Cc: julien.grall, tim, xen-devel
On Fri, 2013-12-06 at 17:38 +0000, Stefano Stabellini wrote:
> On Thu, 5 Dec 2013, Ian Campbell wrote:
> > @@ -227,12 +242,18 @@ static int vtimer_emulate_sysreg(struct cpu_user_regs *regs, union hsr hsr)
> > {
> > case CNTP_CTL_EL0:
> > vtimer_cntp_ctl(regs, &r, sysreg.read);
> > - *x = r;
> > + if ( sysreg.read )
> > + *x = r;
> > return 1;
> > case CNTP_TVAL_EL0:
> > vtimer_cntp_tval(regs, &r, sysreg.read);
> > - *x = r;
> > + if ( sysreg.read )
> > + *x = r;
> > return 1;
>
> Are you sure that sysreg.read == 1 means write?
On the contrary, it means read.
Here x points to the guest reg that is the target of the read, and r is
the new value which the emulation has produced.
So *x = r is implementing a read from the guest's PoV.
Ian.
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] xen: arm: vtimer fixes for arm64
2013-12-06 17:42 ` Ian Campbell
@ 2013-12-06 17:49 ` Stefano Stabellini
0 siblings, 0 replies; 6+ messages in thread
From: Stefano Stabellini @ 2013-12-06 17:49 UTC (permalink / raw)
To: Ian Campbell; +Cc: xen-devel, tim, julien.grall, Stefano Stabellini
On Fri, 6 Dec 2013, Ian Campbell wrote:
> On Fri, 2013-12-06 at 17:38 +0000, Stefano Stabellini wrote:
> > On Thu, 5 Dec 2013, Ian Campbell wrote:
> > > @@ -227,12 +242,18 @@ static int vtimer_emulate_sysreg(struct cpu_user_regs *regs, union hsr hsr)
> > > {
> > > case CNTP_CTL_EL0:
> > > vtimer_cntp_ctl(regs, &r, sysreg.read);
> > > - *x = r;
> > > + if ( sysreg.read )
> > > + *x = r;
> > > return 1;
> > > case CNTP_TVAL_EL0:
> > > vtimer_cntp_tval(regs, &r, sysreg.read);
> > > - *x = r;
> > > + if ( sysreg.read )
> > > + *x = r;
> > > return 1;
> >
> > Are you sure that sysreg.read == 1 means write?
>
> On the contrary, it means read.
>
> Here x points to the guest reg that is the target of the read, and r is
> the new value which the emulation has produced.
>
> So *x = r is implementing a read from the guest's PoV.
Ops, that's right.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
^ permalink raw reply [flat|nested] 6+ messages in thread
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2013-12-05 12:58 [PATCH] xen: arm: vtimer fixes for arm64 Ian Campbell
2013-12-06 16:30 ` Julien Grall
2013-12-06 17:06 ` Ian Campbell
2013-12-06 17:38 ` Stefano Stabellini
2013-12-06 17:42 ` Ian Campbell
2013-12-06 17:49 ` Stefano Stabellini
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