| Message ID | 20201015042516.41197-3-takahiro.akashi@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | xen: improve console outputs | expand |
> Subject: [PATCH 2/4] arch: arm/xen: add putc() for debugging > > This new function, xen_debug_putc(), is intended to be used to enable > CONFIG_DEBUG_UART on xen guest. > > Please note that the underlying functionality in Xen is available only when Xen > is configured with !NDEBUG but is much simpler than a generic > HYPERVISOR_console_io(). > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > --- > arch/arm/include/asm/xen/hypercall.h | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/arm/include/asm/xen/hypercall.h > b/arch/arm/include/asm/xen/hypercall.h > index a4fd077079a9..121ccfcc608f 100644 > --- a/arch/arm/include/asm/xen/hypercall.h > +++ b/arch/arm/include/asm/xen/hypercall.h > @@ -19,4 +19,10 @@ int HYPERVISOR_sched_op(int cmd, void *arg); int > HYPERVISOR_event_channel_op(int cmd, void *arg); unsigned long > HYPERVISOR_hvm_op(int op, void *arg); int > HYPERVISOR_memory_op(unsigned int cmd, void *arg); > + > +static inline void xen_debug_putc(int c) { > + register int v __asm__ ("x0") = c; > + __asm__ __volatile__("hvc 0xfffe" : "=r" (v) : "0" (v)); } > #endif /* _ASM_ARM_XEN_HYPERCALL_H */ Reviewed-by: Peng Fan <peng.fan@nxp.com> > -- > 2.28.0
On Thu, Oct 15, 2020 at 01:25:14PM +0900, AKASHI Takahiro wrote: > This new function, xen_debug_putc(), is intended to be used to > enable CONFIG_DEBUG_UART on xen guest. > > Please note that the underlying functionality in Xen is available > only when Xen is configured with !NDEBUG but is much simpler than > a generic HYPERVISOR_console_io(). > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > Reviewed-by: Peng Fan <peng.fan@nxp.com> Applied to u-boot/master, thanks! -- Tom
diff --git a/arch/arm/include/asm/xen/hypercall.h b/arch/arm/include/asm/xen/hypercall.h index a4fd077079a9..121ccfcc608f 100644 --- a/arch/arm/include/asm/xen/hypercall.h +++ b/arch/arm/include/asm/xen/hypercall.h @@ -19,4 +19,10 @@ int HYPERVISOR_sched_op(int cmd, void *arg); int HYPERVISOR_event_channel_op(int cmd, void *arg); unsigned long HYPERVISOR_hvm_op(int op, void *arg); int HYPERVISOR_memory_op(unsigned int cmd, void *arg); + +static inline void xen_debug_putc(int c) +{ + register int v __asm__ ("x0") = c; + __asm__ __volatile__("hvc 0xfffe" : "=r" (v) : "0" (v)); +} #endif /* _ASM_ARM_XEN_HYPERCALL_H */
This new function, xen_debug_putc(), is intended to be used to enable CONFIG_DEBUG_UART on xen guest. Please note that the underlying functionality in Xen is available only when Xen is configured with !NDEBUG but is much simpler than a generic HYPERVISOR_console_io(). Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> --- arch/arm/include/asm/xen/hypercall.h | 6 ++++++ 1 file changed, 6 insertions(+) -- 2.28.0