uart: Decreases timeouts to reduce latency

This commit is contained in:
CTCaer 2020-06-14 13:21:59 +03:00
parent 48f84c5cf4
commit 157e415636
2 changed files with 12 additions and 18 deletions

View file

@ -85,27 +85,24 @@ void uart_send(u32 idx, const u8 *buf, u32 len)
u32 uart_recv(u32 idx, u8 *buf, u32 len)
{
uart_t *uart = (uart_t *)(UART_BASE + uart_baseoff[idx]);
u32 timeout = get_tmr_us() + 1000;
u32 timeout = get_tmr_us() + 250;
u32 i;
for (i = 0; ; i++)
{
while (!(uart->UART_LSR & UART_LSR_RDR))
{
if (!len)
{
if (timeout < get_tmr_us())
break;
}
else if (len < i)
if (timeout < get_tmr_us())
break;
if (len && len < i)
break;
}
if (timeout < get_tmr_us())
break;
buf[i] = uart->UART_THR_DLAB;
timeout = get_tmr_us() + 1000;
};
timeout = get_tmr_us() + 250;
}
return i ? (len ? (i - 1) : i) : 0;
}

View file

@ -85,27 +85,24 @@ void uart_send(u32 idx, const u8 *buf, u32 len)
u32 uart_recv(u32 idx, u8 *buf, u32 len)
{
uart_t *uart = (uart_t *)(UART_BASE + uart_baseoff[idx]);
u32 timeout = get_tmr_us() + 1000;
u32 timeout = get_tmr_us() + 250;
u32 i;
for (i = 0; ; i++)
{
while (!(uart->UART_LSR & UART_LSR_RDR))
{
if (!len)
{
if (timeout < get_tmr_us())
break;
}
else if (len < i)
if (timeout < get_tmr_us())
break;
if (len && len < i)
break;
}
if (timeout < get_tmr_us())
break;
buf[i] = uart->UART_THR_DLAB;
timeout = get_tmr_us() + 1000;
};
timeout = get_tmr_us() + 250;
}
return i ? (len ? (i - 1) : i) : 0;
}