FreeCalypso > hg > freecalypso-tools
view target-utils/libbase/serio.S @ 619:f82551c77e58
libserial-newlnx: ASYNC_LOW_LATENCY patch reverted
Reports from Das Signal indicate that loadtools performance on Debian
is about the same as on Slackware, and that including or omitting the
ASYNC_LOW_LATENCY patch from Serg makes no difference. Because the
patch in question does not appear to be necessary, it is being reverted
until and unless someone other than Serg reports an actual real-world
system on which loadtools operation times are slowed compared to the
Mother's Slackware reference and on which Slackware-like performance
can be restored by setting the ASYNC_LOW_LATENCY flag.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Thu, 27 Feb 2020 01:09:48 +0000 |
| parents | da6df2c626cf |
| children |
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#include "ns16550.h" @ this module implements the elementary serial I/O operations .comm uart_base,4,4 .text .code 32 .global serial_out serial_out: ldr r1, =uart_base ldr r2, [r1] 1: ldrb r3, [r2, #0x11] @ Calypso UART non-std register SSR tst r3, #0x01 @ Tx FIFO full flag bne 1b strb r0, [r2, #NS16550_THR] bx lr .global serial_in_poll serial_in_poll: ldr r1, =uart_base ldr r2, [r1] ldrb r3, [r2, #NS16550_LSR] tst r3, #NS16550_LSR_DR ldrneb r0, [r2, #NS16550_RBR] mvneq r0, #0 bx lr .global serial_flush serial_flush: ldr r1, =uart_base ldr r2, [r1] 1: ldrb r3, [r2, #NS16550_LSR] tst r3, #NS16550_LSR_TEMP beq 1b bx lr