On Fri, 7 May 2021 13:45:57 +0200 Ahmad Fatoum <[email protected]> wrote:
> Hi, > > On 07.05.21 00:08, Antony Pavlov wrote: > > Signed-off-by: Antony Pavlov <[email protected]> > > --- > > drivers/serial/Makefile | 1 + > > drivers/serial/serial_litex.c | 96 +++++++++++++++++++++++++++++++++++ > > 2 files changed, 97 insertions(+) > > > > diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile > > index 5120b17376..45055371ea 100644 > > --- a/drivers/serial/Makefile > > +++ b/drivers/serial/Makefile > > @@ -24,3 +24,4 @@ obj-$(CONFIG_DRIVER_SERIAL_DIGIC) += > > serial_digic.o > > obj-$(CONFIG_DRIVER_SERIAL_LPUART) += serial_lpuart.o > > obj-$(CONFIG_VIRTIO_CONSOLE) += virtio_console.o > > obj-$(CONFIG_SERIAL_SIFIVE) += serial_sifive.o > > +obj-$(CONFIG_SOC_LITEX) += serial_litex.o > > diff --git a/drivers/serial/serial_litex.c b/drivers/serial/serial_litex.c > > new file mode 100644 > > index 0000000000..8562a45ecc > > --- /dev/null > > +++ b/drivers/serial/serial_litex.c > > @@ -0,0 +1,96 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Copyright (C) 2019 Antony Pavlov <[email protected]> > > + * > > + */ > > + > > +#include <common.h> > > +#include <init.h> > > +#include <io.h> > > + > > +#define UART_RXTX 0x00 > > +#define UART_TXFULL 0x04 > > +#define UART_RXEMPTY 0x08 > > +#define UART_EV_PENDING 0x10 > > +#define UART_EV_RX (1 << 1) > > + > > +static inline uint32_t litex_serial_readb(struct console_device *cdev, > > + uint32_t offset) > > +{ > > + void __iomem *base = cdev->dev->priv; > > + > > + return readb(base + offset); > > +} > > + > > +static inline void litex_serial_writeb(struct console_device *cdev, > > + uint32_t value, uint32_t offset) > > +{ > > + void __iomem *base = cdev->dev->priv; > > + > > + writeb(value, base + offset); > > +} > > + > > +static void litex_serial_putc(struct console_device *cdev, char c) > > +{ > > + while (litex_serial_readb(cdev, UART_TXFULL)) > > + ; > > + > > + litex_serial_writeb(cdev, c, UART_RXTX); > > +} > > + > > +static int litex_serial_getc(struct console_device *cdev) > > +{ > > + int c; > > + > > + while (litex_serial_readb(cdev, UART_RXEMPTY)) > > + ; > > + > > + c = litex_serial_readb(cdev, UART_RXTX); > > + > > + /* refresh UART_RXEMPTY by writing UART_EV_RX to UART_EV_PENDING */ > > + litex_serial_writeb(cdev, UART_EV_RX, UART_EV_PENDING); > > + > > + return c; > > +} > > + > > +static int litex_serial_tstc(struct console_device *cdev) > > +{ > > + return !litex_serial_readb(cdev, UART_RXEMPTY); > > +} > > + > > +static int litex_serial_probe(struct device_d *dev) > > +{ > > + struct resource *iores; > > + struct console_device *cdev; > > + > > + cdev = xzalloc(sizeof(struct console_device)); > > + iores = dev_request_mem_resource(dev, 0); > > + if (IS_ERR(iores)) > > + return PTR_ERR(iores); > > + > > + dev->priv = IOMEM(iores->start); > > + cdev->dev = dev; > > + cdev->tstc = &litex_serial_tstc; > > + cdev->putc = &litex_serial_putc; > > + cdev->getc = &litex_serial_getc; > > + cdev->setbrg = NULL; > > Does the IP only output a fixed baudrate/configuration? Yes, this IP works at fixed baudrate. Baudrate is selected during FPGA bitstream compilation, e.g. see https://github.com/litex-hub/linux-on-litex-vexriscv/commit/0b133cc3 At the moment there is a problem with this fixed speed port: loady command does not work. > > + > > + console_register(cdev); > > + > > + return 0; > > +} > > + > > +static __maybe_unused struct of_device_id litex_serial_dt_ids[] = { > > + { > > + .compatible = "litex,uart", > > + }, { > > + /* sentinel */ > > + } > > +}; > > + > > +static struct driver_d litex_serial_driver = { > > + .name = "litex-uart", > > + .probe = litex_serial_probe, > > + .of_compatible = DRV_OF_COMPAT(litex_serial_dt_ids), > > +}; > > +console_platform_driver(litex_serial_driver); > > > > -- > Pengutronix e.K. | | > Steuerwalder Str. 21 | http://www.pengutronix.de/ | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- Best regards, Antony Pavlov _______________________________________________ barebox mailing list [email protected] http://lists.infradead.org/mailman/listinfo/barebox
