From 5208e7ced520a813b4f4774451fbac4e517e78b2 Mon Sep 17 00:00:00 2001 From: Doug Brown Date: Sun, 19 May 2024 12:19:30 -0700 Subject: [PATCH] serial: 8250_pxa: Configure tx_loadsz to match FIFO IRQ level The FIFO is 64 bytes, but the FCR is configured to fire the TX interrupt when the FIFO is half empty (bit 3 = 0). Thus, we should only write 32 bytes when a TX interrupt occurs. This fixes a problem observed on the PXA168 that dropped a bunch of TX bytes during large transmissions. Fixes: ab28f51c77cd ("serial: rewrite pxa2xx-uart to use 8250_core") Signed-off-by: Doug Brown Link: https://lore.kernel.org/r/20240519191929.122202-1-doug@schmorgal.com Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_pxa.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/serial/8250/8250_pxa.c b/drivers/tty/serial/8250/8250_pxa.c index f1a51b00b1b9..ba96fa913e7f 100644 --- a/drivers/tty/serial/8250/8250_pxa.c +++ b/drivers/tty/serial/8250/8250_pxa.c @@ -125,6 +125,7 @@ static int serial_pxa_probe(struct platform_device *pdev) uart.port.iotype = UPIO_MEM32; uart.port.regshift = 2; uart.port.fifosize = 64; + uart.tx_loadsz = 32; uart.dl_write = serial_pxa_dl_write; ret = serial8250_register_8250_port(&uart);