diff options
| author | Justin Chen <justin.chen@broadcom.com> | 2023-08-21 21:52:51 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-22 16:30:59 +0300 |
| commit | 42a569cd0d774fd575395a84481f87a1aaa530df (patch) | |
| tree | dfca86006a45ac3a8b007bca8e8af0971bac24ce | |
| parent | b4a778303ea0fcabcaff974721477a5743e1f8ec (diff) | |
| download | linux-42a569cd0d774fd575395a84481f87a1aaa530df.tar.xz | |
serial: 8250_bcm7271: improve bcm7271 8250 port
The 8250 BCM7271 UART is not a direct match to PORT_16550A and other
generic ports do not match its hardware capabilities. PORT_ALTR matches
the rx trigger levels, but its vendor configurations are not compatible.
Unfortunately this means we need to create another port to fully capture
the hardware capabilities of the BCM7271 UART.
To alleviate some latency pressures, we default the rx trigger level to 8.
Signed-off-by: Justin Chen <justin.chen@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Acked-by: Doug Berger <opendmb@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/1692643978-16570-1-git-send-email-justin.chen@broadcom.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/8250/8250_bcm7271.c | 4 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 8 | ||||
| -rw-r--r-- | include/uapi/linux/serial_core.h | 3 |
3 files changed, 12 insertions, 3 deletions
diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c index d4b05d7ad9e8..aa5aff046756 100644 --- a/drivers/tty/serial/8250/8250_bcm7271.c +++ b/drivers/tty/serial/8250/8250_bcm7271.c @@ -1042,7 +1042,7 @@ static int brcmuart_probe(struct platform_device *pdev) dev_dbg(dev, "DMA is %senabled\n", priv->dma_enabled ? "" : "not "); memset(&up, 0, sizeof(up)); - up.port.type = PORT_16550A; + up.port.type = PORT_BCM7271; up.port.uartclk = clk_rate; up.port.dev = dev; up.port.mapbase = mapbase; @@ -1056,8 +1056,6 @@ static int brcmuart_probe(struct platform_device *pdev) | UPF_FIXED_PORT | UPF_FIXED_TYPE; up.port.dev = dev; up.port.private_data = priv; - up.capabilities = UART_CAP_FIFO | UART_CAP_AFE; - up.port.fifosize = 32; /* Check for a fixed line number */ ret = of_alias_get_id(np, "serial"); diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index f59328e1c35d..fb891b67968f 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -322,6 +322,14 @@ static const struct serial8250_config uart_config[] = { .rxtrig_bytes = {2, 66, 130, 194}, .flags = UART_CAP_FIFO, }, + [PORT_BCM7271] = { + .name = "Broadcom BCM7271 UART", + .fifo_size = 32, + .tx_loadsz = 32, + .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01, + .rxtrig_bytes = {1, 8, 16, 30}, + .flags = UART_CAP_FIFO | UART_CAP_AFE, + }, }; /* Uart divisor latch read */ diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h index d19dabd2c20d..add349889d0a 100644 --- a/include/uapi/linux/serial_core.h +++ b/include/uapi/linux/serial_core.h @@ -123,6 +123,9 @@ /* Xilinx uartlite */ #define PORT_UARTLITE 74 +/* Broadcom BCM7271 UART */ +#define PORT_BCM7271 76 + /* Broadcom SB1250, etc. SOC */ #define PORT_SB1250_DUART 77 |