Hi, I tested this on the foundation model and it hangs.
-Geoff On Thu, 2015-05-14 at 11:25 +0530, Pratyush Anand wrote: > Previous transmission must be completed before next character to be > transmitted, otherwise TX buffer may saturate and we will not see all > the characters on screen. > > Signed-off-by: Pratyush Anand <[email protected]> > --- > purgatory/arch/arm64/purgatory-arm64.c | 24 +++++++++++++++++++++++- > 1 file changed, 23 insertions(+), 1 deletion(-) > > diff --git a/purgatory/arch/arm64/purgatory-arm64.c > b/purgatory/arch/arm64/purgatory-arm64.c > index 25960c30bd05..3a1c9243bfa2 100644 > --- a/purgatory/arch/arm64/purgatory-arm64.c > +++ b/purgatory/arch/arm64/purgatory-arm64.c > @@ -11,15 +11,37 @@ extern uint32_t *arm64_sink; > extern void (*arm64_kernel_entry)(uint64_t); > extern uint64_t arm64_dtb_addr; > > +static void wait_for_xmit_complete(void) > +{ > + volatile uint32_t status; > + volatile uint32_t *status_reg; > + > + /* > + * Since most of the UART with ARM platform has LSR register > at > + * offset 0x14 and should have value as 0x60 for TX empty, > so we > + * have hardcoded these values. Can modify in future if need > + * arises. > + */ > + status_reg = (volatile uint32_t *)((uint64_t)arm64_sink + > 0x14); > + while (1) { > + status = *status_reg; > + if ((status & 0x60) == 0x60) > + break; > + } > +} > + > void putchar(int ch) > { > if (!arm64_sink) > return; > > + wait_for_xmit_complete(); > *arm64_sink = ch; > > - if (ch == '\n') > + if (ch == '\n') { > + wait_for_xmit_complete(); > *arm64_sink = '\r'; > + } > } > > void setup_arch(void) _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
