On 6/24/2024 10:26 PM, Udit Kumar wrote:
As per Errata i2310[0], Erroneous timeout can be triggered, if this Erroneous interrupt is not cleared then it may leads to storm of interrupts, therefore apply Errata i2310 solution.
[0] https://www.ti.com/lit/pdf/sprz536 page 23
Fixes: b67e830d38fa ("serial: 8250: 8250_omap: Fix possible interrupt storm on K3 SoCs") Cc: stable@vger.kernel.org Signed-off-by: Udit Kumar u-kumar1@ti.com
[...]
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 170639d12b2a..1af9aed99c65 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -115,6 +115,10 @@ /* RX FIFO occupancy indicator */ #define UART_OMAP_RX_LVL 0x19 +/* Timeout low and High */ +#define UART_OMAP_TO_L 0x26 +#define UART_OMAP_TO_H 0x27
/*
- Copy of the genpd flags for the console.
- Only used if console suspend is disabled
@@ -663,13 +667,25 @@ static irqreturn_t omap8250_irq(int irq, void *dev_id) /* * On K3 SoCs, it is observed that RX TIMEOUT is signalled after
* FIFO has been drained, in which case a dummy read of RX FIFO* is required to clear RX TIMEOUT condition.
* FIFO has been drained or erroneously.* So apply solution of Errata i2310 as mentioned in* https://www.ti.com/lit/pdf/sprz536
serial_port_in(port, UART_RX);
unsigned char efr2, timeout_h, timeout_l;efr2 = serial_in(up, UART_OMAP_EFR2);timeout_h = serial_in(up, UART_OMAP_TO_H);timeout_l = serial_in(up, UART_OMAP_TO_L);serial_out(up, UART_OMAP_TO_H, 0xFF);serial_out(up, UART_OMAP_TO_L, 0xFF);serial_out(up, UART_OMAP_EFR2, UART_OMAP_EFR2_TIMEOUT_BEHAVE);serial_in(up, UART_IIR);serial_out(up, UART_OMAP_EFR2, efr2);serial_out(up, UART_OMAP_TO_H, timeout_h);serial_out(up, UART_OMAP_TO_L, timeout_l);/* Stop processing interrupts on input overrun */
Reviewed-by: Vignesh Raghavendra vigneshr@ti.com