diff options
| -rw-r--r-- | hw/lpc-uart.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/hw/lpc-uart.c b/hw/lpc-uart.c index 51f744d..7f0909a 100644 --- a/hw/lpc-uart.c +++ b/hw/lpc-uart.c @@ -57,11 +57,12 @@ DEFINE_LOG_ENTRY(OPAL_RC_UART_INIT, OPAL_PLATFORM_ERR_EVT, OPAL_UART, #define IER_RX 0x01 #define IER_THRE 0x02 +#define IER_ALL 0x0f static struct lock uart_lock = LOCK_UNLOCKED; static struct dt_node *uart_node; static uint32_t uart_base; -static bool has_irq, rx_full, tx_full; +static bool has_irq, irq_ok, rx_full, tx_full; static uint8_t tx_room; static uint8_t cached_ier; @@ -110,6 +111,13 @@ static void uart_update_ier(void) if (!has_irq) return; + /* If we have never got an interrupt, enable them all, + * the first interrupt received will tell us if interrupts + * are functional (some boards are missing an EC or FPGA + * programming causing LPC interrupts not to work). + */ + if (!irq_ok) + ier = IER_ALL; if (!rx_full) ier |= IER_RX; if (tx_full) @@ -182,8 +190,18 @@ static void uart_flush_out(void) bool tx_was_full = tx_full; while(out_buf_prod != out_buf_cons) { - if (tx_room == 0) - uart_check_tx_room(); + if (tx_room == 0) { + /* + * If the interrupt is not functional, + * we force a full synchronous flush, + * otherwise the Linux console isn't + * usable (too slow). + */ + if (irq_ok) + uart_check_tx_room(); + else + uart_wait_tx_room(); + } if (tx_room == 0) { tx_full = true; break; @@ -345,6 +363,10 @@ static void uart_console_poll(void *data __unused) void uart_irq(void) { + if (!irq_ok) { + printf("UART: IRQ functional !\n"); + irq_ok = true; + } __uart_do_poll(TRACE_UART_CTX_IRQ); } |