Message ID | 20181205062924.26640-2-anup@brainfault.org |
---|---|
State | Superseded |
Delegated to: | Andes |
Headers | show |
Series | SiFive UART support | expand |
On Tue, 04 Dec 2018 22:29:23 PST (-0800), anup@brainfault.org wrote: > This patch adds SiFive UART driver. The driver is 100% DM driver > and it determines input clock using clk framework. > > Signed-off-by: Anup Patel <anup@brainfault.org> > --- > drivers/serial/Kconfig | 13 +++ > drivers/serial/Makefile | 1 + > drivers/serial/serial_sifive.c | 193 +++++++++++++++++++++++++++++++++ > 3 files changed, 207 insertions(+) > create mode 100644 drivers/serial/serial_sifive.c > > diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig > index 3bcc61e731..30f7e00557 100644 > --- a/drivers/serial/Kconfig > +++ b/drivers/serial/Kconfig > @@ -343,6 +343,13 @@ config DEBUG_UART_SANDBOX > start up driver model. The driver will be available until the real > driver model serial is running. > > +config DEBUG_UART_SIFIVE > + bool "SiFive UART" > + help > + Select this to enable a debug UART using the serial_sifive driver. You > + will need to provide parameters to make this work. The driver will > + be available until the real driver-model serial is running. > + > config DEBUG_UART_STM32 > bool "STMicroelectronics STM32" > depends on STM32_SERIAL > @@ -685,6 +692,12 @@ config PXA_SERIAL > If you have a machine based on a Marvell XScale PXA2xx CPU you > can enable its onboard serial ports by enabling this option. > > +config SIFIVE_SERIAL > + bool "SiFive UART support" > + depends on DM_SERIAL > + help > + This driver supports the SiFive UART. If unsure say N. > + > config STI_ASC_SERIAL > bool "STMicroelectronics on-chip UART" > depends on DM_SERIAL && ARCH_STI > diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile > index b6377b1076..b6781535a8 100644 > --- a/drivers/serial/Makefile > +++ b/drivers/serial/Makefile > @@ -68,6 +68,7 @@ obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o > obj-$(CONFIG_OWL_SERIAL) += serial_owl.o > obj-$(CONFIG_OMAP_SERIAL) += serial_omap.o > obj-$(CONFIG_MTK_SERIAL) += serial_mtk.o > +obj-$(CONFIG_SIFIVE_SERIAL) += serial_sifive.o > > ifndef CONFIG_SPL_BUILD > obj-$(CONFIG_USB_TTY) += usbtty.o > diff --git a/drivers/serial/serial_sifive.c b/drivers/serial/serial_sifive.c > new file mode 100644 > index 0000000000..cce05d5a01 > --- /dev/null > +++ b/drivers/serial/serial_sifive.c > @@ -0,0 +1,193 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Copyright (C) 2012 Michal Simek <monstr@monstr.eu> > + * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved. > + */ > + > +#include <clk.h> > +#include <common.h> > +#include <debug_uart.h> > +#include <dm.h> > +#include <errno.h> > +#include <fdtdec.h> > +#include <watchdog.h> > +#include <asm/io.h> > +#include <linux/compiler.h> > +#include <serial.h> > + > +DECLARE_GLOBAL_DATA_PTR; > + > +#define UART_TXFIFO_FULL 0x80000000 > +#define UART_RXFIFO_EMPTY 0x80000000 > +#define UART_RXFIFO_DATA 0x000000ff > +#define UART_TXCTRL_TXEN 0x1 > +#define UART_RXCTRL_RXEN 0x1 > + > +struct uart_sifive { > + u32 txfifo; > + u32 rxfifo; > + u32 txctrl; > + u32 rxctrl; > + u32 ie; > + u32 ip; > + u32 div; > +}; > + > +struct sifive_uart_platdata { > + unsigned int clock; > + struct uart_sifive *regs; > +}; > + > +/* Set up the baud rate in gd struct */ > +static void _sifive_serial_setbrg(struct uart_sifive *regs, > + unsigned long clock, unsigned long baud) > +{ > + writel((u32)((clock / baud) - 1), ®s->div); > +} > + > +static void _sifive_serial_init(struct uart_sifive *regs) > +{ > + writel(UART_TXCTRL_TXEN, ®s->txctrl); > + writel(UART_RXCTRL_RXEN, ®s->rxctrl); > + writel(0, ®s->ie); > +} > + > +static int _sifive_serial_putc(struct uart_sifive *regs, const char c) > +{ > + if (readl(®s->txfifo) & UART_TXFIFO_FULL) > + return -EAGAIN; > + > + writel(c, ®s->txfifo); > + > + return 0; > +} > + > +static int _sifive_serial_getc(struct uart_sifive *regs) > +{ > + int ch = readl(®s->rxfifo); > + > + if (ch & UART_RXFIFO_EMPTY) > + return -EAGAIN; > + ch &= UART_RXFIFO_DATA; > + > + return (!ch) ? -EAGAIN : ch; > +} > + > +static int sifive_serial_setbrg(struct udevice *dev, int baudrate) > +{ > + int err; > + struct clk clk; > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + err = clk_get_by_index(dev, 0, &clk); > + if (!err) { > + err = clk_get_rate(&clk); > + if (!IS_ERR_VALUE(err)) > + platdata->clock = err; > + } else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) { > + debug("SiFive UART failed to get clock\n"); > + return err; > + } > + > + if (!platdata->clock) > + platdata->clock = dev_read_u32_default(dev, "clock-frequency", 0); > + if (!platdata->clock) { > + debug("SiFive UART clock not defined\n"); > + return -EINVAL; > + } > + > + _sifive_serial_setbrg(platdata->regs, platdata->clock, baudrate); > + > + return 0; > +} I don't see anything that ensures the TX FIFO is drained before changing the baud rate. I don't know anything about u-boot so I'm not sure if that's expected. > +static int sifive_serial_probe(struct udevice *dev) > +{ > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + /* No need to reinitialize the UART after relocation */ > + if (gd->flags & GD_FLG_RELOC) > + return 0; > + > + _sifive_serial_init(platdata->regs); > + > + return 0; > +} > + > +static int sifive_serial_getc(struct udevice *dev) > +{ > + int c; > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + struct uart_sifive *regs = platdata->regs; > + > + while ((c = _sifive_serial_getc(regs)) == -EAGAIN) ; > + > + return c; > +} > + > +static int sifive_serial_putc(struct udevice *dev, const char ch) > +{ > + int rc; > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + while ((rc = _sifive_serial_putc(platdata->regs, ch)) == -EAGAIN) ; > + > + return rc; > +} > + > +static int sifive_serial_ofdata_to_platdata(struct udevice *dev) > +{ > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + platdata->regs = (struct uart_sifive *)dev_read_addr(dev); > + if (IS_ERR(platdata->regs)) > + return PTR_ERR(platdata->regs); > + > + return 0; > +} > + > +static const struct dm_serial_ops sifive_serial_ops = { > + .putc = sifive_serial_putc, > + .getc = sifive_serial_getc, > + .setbrg = sifive_serial_setbrg, > +}; > + > +static const struct udevice_id sifive_serial_ids[] = { > + { .compatible = "sifive,uart0" }, > + { } > +}; > + > +U_BOOT_DRIVER(serial_sifive) = { > + .name = "serial_sifive", > + .id = UCLASS_SERIAL, > + .of_match = sifive_serial_ids, > + .ofdata_to_platdata = sifive_serial_ofdata_to_platdata, > + .platdata_auto_alloc_size = sizeof(struct sifive_uart_platdata), > + .probe = sifive_serial_probe, > + .ops = &sifive_serial_ops, > + .priv_auto_alloc_size = sizeof(struct sifive_uart_platdata), > +}; > + > +#ifdef CONFIG_DEBUG_UART_SIFIVE > +static inline void _debug_uart_init(void) > +{ > + struct uart_sifive *regs = > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > + > + _sifive_serial_setbrg(regs, CONFIG_DEBUG_UART_CLOCK, > + CONFIG_BAUDRATE); > + _sifive_serial_init(regs); > +} > + > +static inline void _debug_uart_putc(int ch) > +{ > + struct uart_sifive *regs = > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > + > + while (_sifive_serial_putc(regs, ch) == -EAGAIN) > + WATCHDOG_RESET(); > +} > + > +DEBUG_UART_FUNCS > + > +#endif Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Thanks!
Hi Anup, On Wed, Dec 5, 2018 at 2:29 PM Anup Patel <anup@brainfault.org> wrote: > > This patch adds SiFive UART driver. The driver is 100% DM driver > and it determines input clock using clk framework. > > Signed-off-by: Anup Patel <anup@brainfault.org> > --- > drivers/serial/Kconfig | 13 +++ > drivers/serial/Makefile | 1 + > drivers/serial/serial_sifive.c | 193 +++++++++++++++++++++++++++++++++ > 3 files changed, 207 insertions(+) > create mode 100644 drivers/serial/serial_sifive.c > > diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig > index 3bcc61e731..30f7e00557 100644 > --- a/drivers/serial/Kconfig > +++ b/drivers/serial/Kconfig > @@ -343,6 +343,13 @@ config DEBUG_UART_SANDBOX > start up driver model. The driver will be available until the real > driver model serial is running. > > +config DEBUG_UART_SIFIVE > + bool "SiFive UART" > + help > + Select this to enable a debug UART using the serial_sifive driver. You > + will need to provide parameters to make this work. The driver will > + be available until the real driver-model serial is running. > + > config DEBUG_UART_STM32 > bool "STMicroelectronics STM32" > depends on STM32_SERIAL > @@ -685,6 +692,12 @@ config PXA_SERIAL > If you have a machine based on a Marvell XScale PXA2xx CPU you > can enable its onboard serial ports by enabling this option. > > +config SIFIVE_SERIAL > + bool "SiFive UART support" > + depends on DM_SERIAL > + help > + This driver supports the SiFive UART. If unsure say N. > + > config STI_ASC_SERIAL > bool "STMicroelectronics on-chip UART" > depends on DM_SERIAL && ARCH_STI > diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile > index b6377b1076..b6781535a8 100644 > --- a/drivers/serial/Makefile > +++ b/drivers/serial/Makefile > @@ -68,6 +68,7 @@ obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o > obj-$(CONFIG_OWL_SERIAL) += serial_owl.o > obj-$(CONFIG_OMAP_SERIAL) += serial_omap.o > obj-$(CONFIG_MTK_SERIAL) += serial_mtk.o > +obj-$(CONFIG_SIFIVE_SERIAL) += serial_sifive.o > > ifndef CONFIG_SPL_BUILD > obj-$(CONFIG_USB_TTY) += usbtty.o > diff --git a/drivers/serial/serial_sifive.c b/drivers/serial/serial_sifive.c > new file mode 100644 > index 0000000000..cce05d5a01 > --- /dev/null > +++ b/drivers/serial/serial_sifive.c > @@ -0,0 +1,193 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Copyright (C) 2012 Michal Simek <monstr@monstr.eu> > + * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved. nits: pls update the copyright notice > + */ > + > +#include <clk.h> > +#include <common.h> > +#include <debug_uart.h> > +#include <dm.h> > +#include <errno.h> > +#include <fdtdec.h> > +#include <watchdog.h> > +#include <asm/io.h> > +#include <linux/compiler.h> > +#include <serial.h> > + > +DECLARE_GLOBAL_DATA_PTR; > + > +#define UART_TXFIFO_FULL 0x80000000 > +#define UART_RXFIFO_EMPTY 0x80000000 > +#define UART_RXFIFO_DATA 0x000000ff > +#define UART_TXCTRL_TXEN 0x1 > +#define UART_RXCTRL_RXEN 0x1 > + > +struct uart_sifive { > + u32 txfifo; > + u32 rxfifo; > + u32 txctrl; > + u32 rxctrl; > + u32 ie; > + u32 ip; > + u32 div; > +}; > + > +struct sifive_uart_platdata { > + unsigned int clock; > + struct uart_sifive *regs; > +}; > + > +/* Set up the baud rate in gd struct */ > +static void _sifive_serial_setbrg(struct uart_sifive *regs, > + unsigned long clock, unsigned long baud) > +{ > + writel((u32)((clock / baud) - 1), ®s->div); > +} > + > +static void _sifive_serial_init(struct uart_sifive *regs) > +{ > + writel(UART_TXCTRL_TXEN, ®s->txctrl); > + writel(UART_RXCTRL_RXEN, ®s->rxctrl); > + writel(0, ®s->ie); > +} > + > +static int _sifive_serial_putc(struct uart_sifive *regs, const char c) > +{ > + if (readl(®s->txfifo) & UART_TXFIFO_FULL) > + return -EAGAIN; > + > + writel(c, ®s->txfifo); > + > + return 0; > +} > + > +static int _sifive_serial_getc(struct uart_sifive *regs) > +{ > + int ch = readl(®s->rxfifo); > + > + if (ch & UART_RXFIFO_EMPTY) > + return -EAGAIN; > + ch &= UART_RXFIFO_DATA; > + > + return (!ch) ? -EAGAIN : ch; > +} > + > +static int sifive_serial_setbrg(struct udevice *dev, int baudrate) > +{ > + int err; > + struct clk clk; > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + err = clk_get_by_index(dev, 0, &clk); > + if (!err) { > + err = clk_get_rate(&clk); > + if (!IS_ERR_VALUE(err)) > + platdata->clock = err; > + } else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) { > + debug("SiFive UART failed to get clock\n"); > + return err; > + } > + > + if (!platdata->clock) > + platdata->clock = dev_read_u32_default(dev, "clock-frequency", 0); > + if (!platdata->clock) { > + debug("SiFive UART clock not defined\n"); > + return -EINVAL; > + } > + > + _sifive_serial_setbrg(platdata->regs, platdata->clock, baudrate); > + > + return 0; > +} > + > +static int sifive_serial_probe(struct udevice *dev) > +{ > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + /* No need to reinitialize the UART after relocation */ > + if (gd->flags & GD_FLG_RELOC) > + return 0; > + > + _sifive_serial_init(platdata->regs); > + > + return 0; > +} > + > +static int sifive_serial_getc(struct udevice *dev) > +{ > + int c; > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + struct uart_sifive *regs = platdata->regs; > + > + while ((c = _sifive_serial_getc(regs)) == -EAGAIN) ; > + > + return c; > +} > + > +static int sifive_serial_putc(struct udevice *dev, const char ch) > +{ > + int rc; > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + while ((rc = _sifive_serial_putc(platdata->regs, ch)) == -EAGAIN) ; > + > + return rc; > +} > + > +static int sifive_serial_ofdata_to_platdata(struct udevice *dev) > +{ > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > + > + platdata->regs = (struct uart_sifive *)dev_read_addr(dev); > + if (IS_ERR(platdata->regs)) > + return PTR_ERR(platdata->regs); > + > + return 0; > +} > + > +static const struct dm_serial_ops sifive_serial_ops = { > + .putc = sifive_serial_putc, > + .getc = sifive_serial_getc, > + .setbrg = sifive_serial_setbrg, > +}; > + > +static const struct udevice_id sifive_serial_ids[] = { > + { .compatible = "sifive,uart0" }, > + { } > +}; > + > +U_BOOT_DRIVER(serial_sifive) = { > + .name = "serial_sifive", > + .id = UCLASS_SERIAL, > + .of_match = sifive_serial_ids, > + .ofdata_to_platdata = sifive_serial_ofdata_to_platdata, > + .platdata_auto_alloc_size = sizeof(struct sifive_uart_platdata), > + .probe = sifive_serial_probe, > + .ops = &sifive_serial_ops, > + .priv_auto_alloc_size = sizeof(struct sifive_uart_platdata), This is not used anywhere in this driver. > +}; > + > +#ifdef CONFIG_DEBUG_UART_SIFIVE > +static inline void _debug_uart_init(void) > +{ > + struct uart_sifive *regs = > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > + > + _sifive_serial_setbrg(regs, CONFIG_DEBUG_UART_CLOCK, > + CONFIG_BAUDRATE); > + _sifive_serial_init(regs); > +} > + > +static inline void _debug_uart_putc(int ch) > +{ > + struct uart_sifive *regs = > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > + > + while (_sifive_serial_putc(regs, ch) == -EAGAIN) > + WATCHDOG_RESET(); > +} > + > +DEBUG_UART_FUNCS > + > +#endif > -- Regards, Bin
On Mon, Dec 10, 2018 at 7:25 AM Bin Meng <bmeng.cn@gmail.com> wrote: > > Hi Anup, > > On Wed, Dec 5, 2018 at 2:29 PM Anup Patel <anup@brainfault.org> wrote: > > > > This patch adds SiFive UART driver. The driver is 100% DM driver > > and it determines input clock using clk framework. > > > > Signed-off-by: Anup Patel <anup@brainfault.org> > > --- > > drivers/serial/Kconfig | 13 +++ > > drivers/serial/Makefile | 1 + > > drivers/serial/serial_sifive.c | 193 +++++++++++++++++++++++++++++++++ > > 3 files changed, 207 insertions(+) > > create mode 100644 drivers/serial/serial_sifive.c > > > > diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig > > index 3bcc61e731..30f7e00557 100644 > > --- a/drivers/serial/Kconfig > > +++ b/drivers/serial/Kconfig > > @@ -343,6 +343,13 @@ config DEBUG_UART_SANDBOX > > start up driver model. The driver will be available until the real > > driver model serial is running. > > > > +config DEBUG_UART_SIFIVE > > + bool "SiFive UART" > > + help > > + Select this to enable a debug UART using the serial_sifive driver. You > > + will need to provide parameters to make this work. The driver will > > + be available until the real driver-model serial is running. > > + > > config DEBUG_UART_STM32 > > bool "STMicroelectronics STM32" > > depends on STM32_SERIAL > > @@ -685,6 +692,12 @@ config PXA_SERIAL > > If you have a machine based on a Marvell XScale PXA2xx CPU you > > can enable its onboard serial ports by enabling this option. > > > > +config SIFIVE_SERIAL > > + bool "SiFive UART support" > > + depends on DM_SERIAL > > + help > > + This driver supports the SiFive UART. If unsure say N. > > + > > config STI_ASC_SERIAL > > bool "STMicroelectronics on-chip UART" > > depends on DM_SERIAL && ARCH_STI > > diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile > > index b6377b1076..b6781535a8 100644 > > --- a/drivers/serial/Makefile > > +++ b/drivers/serial/Makefile > > @@ -68,6 +68,7 @@ obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o > > obj-$(CONFIG_OWL_SERIAL) += serial_owl.o > > obj-$(CONFIG_OMAP_SERIAL) += serial_omap.o > > obj-$(CONFIG_MTK_SERIAL) += serial_mtk.o > > +obj-$(CONFIG_SIFIVE_SERIAL) += serial_sifive.o > > > > ifndef CONFIG_SPL_BUILD > > obj-$(CONFIG_USB_TTY) += usbtty.o > > diff --git a/drivers/serial/serial_sifive.c b/drivers/serial/serial_sifive.c > > new file mode 100644 > > index 0000000000..cce05d5a01 > > --- /dev/null > > +++ b/drivers/serial/serial_sifive.c > > @@ -0,0 +1,193 @@ > > +// SPDX-License-Identifier: GPL-2.0+ > > +/* > > + * Copyright (C) 2012 Michal Simek <monstr@monstr.eu> > > + * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved. > > nits: pls update the copyright notice Thanks for catching it. I will update it. > > > + */ > > + > > +#include <clk.h> > > +#include <common.h> > > +#include <debug_uart.h> > > +#include <dm.h> > > +#include <errno.h> > > +#include <fdtdec.h> > > +#include <watchdog.h> > > +#include <asm/io.h> > > +#include <linux/compiler.h> > > +#include <serial.h> > > + > > +DECLARE_GLOBAL_DATA_PTR; > > + > > +#define UART_TXFIFO_FULL 0x80000000 > > +#define UART_RXFIFO_EMPTY 0x80000000 > > +#define UART_RXFIFO_DATA 0x000000ff > > +#define UART_TXCTRL_TXEN 0x1 > > +#define UART_RXCTRL_RXEN 0x1 > > + > > +struct uart_sifive { > > + u32 txfifo; > > + u32 rxfifo; > > + u32 txctrl; > > + u32 rxctrl; > > + u32 ie; > > + u32 ip; > > + u32 div; > > +}; > > + > > +struct sifive_uart_platdata { > > + unsigned int clock; > > + struct uart_sifive *regs; > > +}; > > + > > +/* Set up the baud rate in gd struct */ > > +static void _sifive_serial_setbrg(struct uart_sifive *regs, > > + unsigned long clock, unsigned long baud) > > +{ > > + writel((u32)((clock / baud) - 1), ®s->div); > > +} > > + > > +static void _sifive_serial_init(struct uart_sifive *regs) > > +{ > > + writel(UART_TXCTRL_TXEN, ®s->txctrl); > > + writel(UART_RXCTRL_RXEN, ®s->rxctrl); > > + writel(0, ®s->ie); > > +} > > + > > +static int _sifive_serial_putc(struct uart_sifive *regs, const char c) > > +{ > > + if (readl(®s->txfifo) & UART_TXFIFO_FULL) > > + return -EAGAIN; > > + > > + writel(c, ®s->txfifo); > > + > > + return 0; > > +} > > + > > +static int _sifive_serial_getc(struct uart_sifive *regs) > > +{ > > + int ch = readl(®s->rxfifo); > > + > > + if (ch & UART_RXFIFO_EMPTY) > > + return -EAGAIN; > > + ch &= UART_RXFIFO_DATA; > > + > > + return (!ch) ? -EAGAIN : ch; > > +} > > + > > +static int sifive_serial_setbrg(struct udevice *dev, int baudrate) > > +{ > > + int err; > > + struct clk clk; > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + err = clk_get_by_index(dev, 0, &clk); > > + if (!err) { > > + err = clk_get_rate(&clk); > > + if (!IS_ERR_VALUE(err)) > > + platdata->clock = err; > > + } else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) { > > + debug("SiFive UART failed to get clock\n"); > > + return err; > > + } > > + > > + if (!platdata->clock) > > + platdata->clock = dev_read_u32_default(dev, "clock-frequency", 0); > > + if (!platdata->clock) { > > + debug("SiFive UART clock not defined\n"); > > + return -EINVAL; > > + } > > + > > + _sifive_serial_setbrg(platdata->regs, platdata->clock, baudrate); > > + > > + return 0; > > +} > > + > > +static int sifive_serial_probe(struct udevice *dev) > > +{ > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + /* No need to reinitialize the UART after relocation */ > > + if (gd->flags & GD_FLG_RELOC) > > + return 0; > > + > > + _sifive_serial_init(platdata->regs); > > + > > + return 0; > > +} > > + > > +static int sifive_serial_getc(struct udevice *dev) > > +{ > > + int c; > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + struct uart_sifive *regs = platdata->regs; > > + > > + while ((c = _sifive_serial_getc(regs)) == -EAGAIN) ; > > + > > + return c; > > +} > > + > > +static int sifive_serial_putc(struct udevice *dev, const char ch) > > +{ > > + int rc; > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + while ((rc = _sifive_serial_putc(platdata->regs, ch)) == -EAGAIN) ; > > + > > + return rc; > > +} > > + > > +static int sifive_serial_ofdata_to_platdata(struct udevice *dev) > > +{ > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + platdata->regs = (struct uart_sifive *)dev_read_addr(dev); > > + if (IS_ERR(platdata->regs)) > > + return PTR_ERR(platdata->regs); > > + > > + return 0; > > +} > > + > > +static const struct dm_serial_ops sifive_serial_ops = { > > + .putc = sifive_serial_putc, > > + .getc = sifive_serial_getc, > > + .setbrg = sifive_serial_setbrg, > > +}; > > + > > +static const struct udevice_id sifive_serial_ids[] = { > > + { .compatible = "sifive,uart0" }, > > + { } > > +}; > > + > > +U_BOOT_DRIVER(serial_sifive) = { > > + .name = "serial_sifive", > > + .id = UCLASS_SERIAL, > > + .of_match = sifive_serial_ids, > > + .ofdata_to_platdata = sifive_serial_ofdata_to_platdata, > > + .platdata_auto_alloc_size = sizeof(struct sifive_uart_platdata), > > + .probe = sifive_serial_probe, > > + .ops = &sifive_serial_ops, > > + .priv_auto_alloc_size = sizeof(struct sifive_uart_platdata), > > This is not used anywhere in this driver. Ok, I will remove priv_auto_alloc_size. > > > +}; > > + > > +#ifdef CONFIG_DEBUG_UART_SIFIVE > > +static inline void _debug_uart_init(void) > > +{ > > + struct uart_sifive *regs = > > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > > + > > + _sifive_serial_setbrg(regs, CONFIG_DEBUG_UART_CLOCK, > > + CONFIG_BAUDRATE); > > + _sifive_serial_init(regs); > > +} > > + > > +static inline void _debug_uart_putc(int ch) > > +{ > > + struct uart_sifive *regs = > > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > > + > > + while (_sifive_serial_putc(regs, ch) == -EAGAIN) > > + WATCHDOG_RESET(); > > +} > > + > > +DEBUG_UART_FUNCS > > + > > +#endif > > -- > > Regards, > Bin Regards, Anup
On Sat, Dec 8, 2018 at 12:10 AM Palmer Dabbelt <palmer@sifive.com> wrote: > > On Tue, 04 Dec 2018 22:29:23 PST (-0800), anup@brainfault.org wrote: > > This patch adds SiFive UART driver. The driver is 100% DM driver > > and it determines input clock using clk framework. > > > > Signed-off-by: Anup Patel <anup@brainfault.org> > > --- > > drivers/serial/Kconfig | 13 +++ > > drivers/serial/Makefile | 1 + > > drivers/serial/serial_sifive.c | 193 +++++++++++++++++++++++++++++++++ > > 3 files changed, 207 insertions(+) > > create mode 100644 drivers/serial/serial_sifive.c > > > > diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig > > index 3bcc61e731..30f7e00557 100644 > > --- a/drivers/serial/Kconfig > > +++ b/drivers/serial/Kconfig > > @@ -343,6 +343,13 @@ config DEBUG_UART_SANDBOX > > start up driver model. The driver will be available until the real > > driver model serial is running. > > > > +config DEBUG_UART_SIFIVE > > + bool "SiFive UART" > > + help > > + Select this to enable a debug UART using the serial_sifive driver. You > > + will need to provide parameters to make this work. The driver will > > + be available until the real driver-model serial is running. > > + > > config DEBUG_UART_STM32 > > bool "STMicroelectronics STM32" > > depends on STM32_SERIAL > > @@ -685,6 +692,12 @@ config PXA_SERIAL > > If you have a machine based on a Marvell XScale PXA2xx CPU you > > can enable its onboard serial ports by enabling this option. > > > > +config SIFIVE_SERIAL > > + bool "SiFive UART support" > > + depends on DM_SERIAL > > + help > > + This driver supports the SiFive UART. If unsure say N. > > + > > config STI_ASC_SERIAL > > bool "STMicroelectronics on-chip UART" > > depends on DM_SERIAL && ARCH_STI > > diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile > > index b6377b1076..b6781535a8 100644 > > --- a/drivers/serial/Makefile > > +++ b/drivers/serial/Makefile > > @@ -68,6 +68,7 @@ obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o > > obj-$(CONFIG_OWL_SERIAL) += serial_owl.o > > obj-$(CONFIG_OMAP_SERIAL) += serial_omap.o > > obj-$(CONFIG_MTK_SERIAL) += serial_mtk.o > > +obj-$(CONFIG_SIFIVE_SERIAL) += serial_sifive.o > > > > ifndef CONFIG_SPL_BUILD > > obj-$(CONFIG_USB_TTY) += usbtty.o > > diff --git a/drivers/serial/serial_sifive.c b/drivers/serial/serial_sifive.c > > new file mode 100644 > > index 0000000000..cce05d5a01 > > --- /dev/null > > +++ b/drivers/serial/serial_sifive.c > > @@ -0,0 +1,193 @@ > > +// SPDX-License-Identifier: GPL-2.0+ > > +/* > > + * Copyright (C) 2012 Michal Simek <monstr@monstr.eu> > > + * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved. > > + */ > > + > > +#include <clk.h> > > +#include <common.h> > > +#include <debug_uart.h> > > +#include <dm.h> > > +#include <errno.h> > > +#include <fdtdec.h> > > +#include <watchdog.h> > > +#include <asm/io.h> > > +#include <linux/compiler.h> > > +#include <serial.h> > > + > > +DECLARE_GLOBAL_DATA_PTR; > > + > > +#define UART_TXFIFO_FULL 0x80000000 > > +#define UART_RXFIFO_EMPTY 0x80000000 > > +#define UART_RXFIFO_DATA 0x000000ff > > +#define UART_TXCTRL_TXEN 0x1 > > +#define UART_RXCTRL_RXEN 0x1 > > + > > +struct uart_sifive { > > + u32 txfifo; > > + u32 rxfifo; > > + u32 txctrl; > > + u32 rxctrl; > > + u32 ie; > > + u32 ip; > > + u32 div; > > +}; > > + > > +struct sifive_uart_platdata { > > + unsigned int clock; > > + struct uart_sifive *regs; > > +}; > > + > > +/* Set up the baud rate in gd struct */ > > +static void _sifive_serial_setbrg(struct uart_sifive *regs, > > + unsigned long clock, unsigned long baud) > > +{ > > + writel((u32)((clock / baud) - 1), ®s->div); > > +} > > + > > +static void _sifive_serial_init(struct uart_sifive *regs) > > +{ > > + writel(UART_TXCTRL_TXEN, ®s->txctrl); > > + writel(UART_RXCTRL_RXEN, ®s->rxctrl); > > + writel(0, ®s->ie); > > +} > > + > > +static int _sifive_serial_putc(struct uart_sifive *regs, const char c) > > +{ > > + if (readl(®s->txfifo) & UART_TXFIFO_FULL) > > + return -EAGAIN; > > + > > + writel(c, ®s->txfifo); > > + > > + return 0; > > +} > > + > > +static int _sifive_serial_getc(struct uart_sifive *regs) > > +{ > > + int ch = readl(®s->rxfifo); > > + > > + if (ch & UART_RXFIFO_EMPTY) > > + return -EAGAIN; > > + ch &= UART_RXFIFO_DATA; > > + > > + return (!ch) ? -EAGAIN : ch; > > +} > > + > > +static int sifive_serial_setbrg(struct udevice *dev, int baudrate) > > +{ > > + int err; > > + struct clk clk; > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + err = clk_get_by_index(dev, 0, &clk); > > + if (!err) { > > + err = clk_get_rate(&clk); > > + if (!IS_ERR_VALUE(err)) > > + platdata->clock = err; > > + } else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) { > > + debug("SiFive UART failed to get clock\n"); > > + return err; > > + } > > + > > + if (!platdata->clock) > > + platdata->clock = dev_read_u32_default(dev, "clock-frequency", 0); > > + if (!platdata->clock) { > > + debug("SiFive UART clock not defined\n"); > > + return -EINVAL; > > + } > > + > > + _sifive_serial_setbrg(platdata->regs, platdata->clock, baudrate); > > + > > + return 0; > > +} > > I don't see anything that ensures the TX FIFO is drained before changing the > baud rate. I don't know anything about u-boot so I'm not sure if that's > expected. Ohh yes, u-boot serial drivers usually don't drain TX FIFO. If required we can add it via separate patch. > > > +static int sifive_serial_probe(struct udevice *dev) > > +{ > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + /* No need to reinitialize the UART after relocation */ > > + if (gd->flags & GD_FLG_RELOC) > > + return 0; > > + > > + _sifive_serial_init(platdata->regs); > > + > > + return 0; > > +} > > + > > +static int sifive_serial_getc(struct udevice *dev) > > +{ > > + int c; > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + struct uart_sifive *regs = platdata->regs; > > + > > + while ((c = _sifive_serial_getc(regs)) == -EAGAIN) ; > > + > > + return c; > > +} > > + > > +static int sifive_serial_putc(struct udevice *dev, const char ch) > > +{ > > + int rc; > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + while ((rc = _sifive_serial_putc(platdata->regs, ch)) == -EAGAIN) ; > > + > > + return rc; > > +} > > + > > +static int sifive_serial_ofdata_to_platdata(struct udevice *dev) > > +{ > > + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); > > + > > + platdata->regs = (struct uart_sifive *)dev_read_addr(dev); > > + if (IS_ERR(platdata->regs)) > > + return PTR_ERR(platdata->regs); > > + > > + return 0; > > +} > > + > > +static const struct dm_serial_ops sifive_serial_ops = { > > + .putc = sifive_serial_putc, > > + .getc = sifive_serial_getc, > > + .setbrg = sifive_serial_setbrg, > > +}; > > + > > +static const struct udevice_id sifive_serial_ids[] = { > > + { .compatible = "sifive,uart0" }, > > + { } > > +}; > > + > > +U_BOOT_DRIVER(serial_sifive) = { > > + .name = "serial_sifive", > > + .id = UCLASS_SERIAL, > > + .of_match = sifive_serial_ids, > > + .ofdata_to_platdata = sifive_serial_ofdata_to_platdata, > > + .platdata_auto_alloc_size = sizeof(struct sifive_uart_platdata), > > + .probe = sifive_serial_probe, > > + .ops = &sifive_serial_ops, > > + .priv_auto_alloc_size = sizeof(struct sifive_uart_platdata), > > +}; > > + > > +#ifdef CONFIG_DEBUG_UART_SIFIVE > > +static inline void _debug_uart_init(void) > > +{ > > + struct uart_sifive *regs = > > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > > + > > + _sifive_serial_setbrg(regs, CONFIG_DEBUG_UART_CLOCK, > > + CONFIG_BAUDRATE); > > + _sifive_serial_init(regs); > > +} > > + > > +static inline void _debug_uart_putc(int ch) > > +{ > > + struct uart_sifive *regs = > > + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; > > + > > + while (_sifive_serial_putc(regs, ch) == -EAGAIN) > > + WATCHDOG_RESET(); > > +} > > + > > +DEBUG_UART_FUNCS > > + > > +#endif > > Reviewed-by: Palmer Dabbelt <palmer@sifive.com> > Thanks, Anup
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 3bcc61e731..30f7e00557 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -343,6 +343,13 @@ config DEBUG_UART_SANDBOX start up driver model. The driver will be available until the real driver model serial is running. +config DEBUG_UART_SIFIVE + bool "SiFive UART" + help + Select this to enable a debug UART using the serial_sifive driver. You + will need to provide parameters to make this work. The driver will + be available until the real driver-model serial is running. + config DEBUG_UART_STM32 bool "STMicroelectronics STM32" depends on STM32_SERIAL @@ -685,6 +692,12 @@ config PXA_SERIAL If you have a machine based on a Marvell XScale PXA2xx CPU you can enable its onboard serial ports by enabling this option. +config SIFIVE_SERIAL + bool "SiFive UART support" + depends on DM_SERIAL + help + This driver supports the SiFive UART. If unsure say N. + config STI_ASC_SERIAL bool "STMicroelectronics on-chip UART" depends on DM_SERIAL && ARCH_STI diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index b6377b1076..b6781535a8 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -68,6 +68,7 @@ obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o obj-$(CONFIG_OWL_SERIAL) += serial_owl.o obj-$(CONFIG_OMAP_SERIAL) += serial_omap.o obj-$(CONFIG_MTK_SERIAL) += serial_mtk.o +obj-$(CONFIG_SIFIVE_SERIAL) += serial_sifive.o ifndef CONFIG_SPL_BUILD obj-$(CONFIG_USB_TTY) += usbtty.o diff --git a/drivers/serial/serial_sifive.c b/drivers/serial/serial_sifive.c new file mode 100644 index 0000000000..cce05d5a01 --- /dev/null +++ b/drivers/serial/serial_sifive.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2012 Michal Simek <monstr@monstr.eu> + * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved. + */ + +#include <clk.h> +#include <common.h> +#include <debug_uart.h> +#include <dm.h> +#include <errno.h> +#include <fdtdec.h> +#include <watchdog.h> +#include <asm/io.h> +#include <linux/compiler.h> +#include <serial.h> + +DECLARE_GLOBAL_DATA_PTR; + +#define UART_TXFIFO_FULL 0x80000000 +#define UART_RXFIFO_EMPTY 0x80000000 +#define UART_RXFIFO_DATA 0x000000ff +#define UART_TXCTRL_TXEN 0x1 +#define UART_RXCTRL_RXEN 0x1 + +struct uart_sifive { + u32 txfifo; + u32 rxfifo; + u32 txctrl; + u32 rxctrl; + u32 ie; + u32 ip; + u32 div; +}; + +struct sifive_uart_platdata { + unsigned int clock; + struct uart_sifive *regs; +}; + +/* Set up the baud rate in gd struct */ +static void _sifive_serial_setbrg(struct uart_sifive *regs, + unsigned long clock, unsigned long baud) +{ + writel((u32)((clock / baud) - 1), ®s->div); +} + +static void _sifive_serial_init(struct uart_sifive *regs) +{ + writel(UART_TXCTRL_TXEN, ®s->txctrl); + writel(UART_RXCTRL_RXEN, ®s->rxctrl); + writel(0, ®s->ie); +} + +static int _sifive_serial_putc(struct uart_sifive *regs, const char c) +{ + if (readl(®s->txfifo) & UART_TXFIFO_FULL) + return -EAGAIN; + + writel(c, ®s->txfifo); + + return 0; +} + +static int _sifive_serial_getc(struct uart_sifive *regs) +{ + int ch = readl(®s->rxfifo); + + if (ch & UART_RXFIFO_EMPTY) + return -EAGAIN; + ch &= UART_RXFIFO_DATA; + + return (!ch) ? -EAGAIN : ch; +} + +static int sifive_serial_setbrg(struct udevice *dev, int baudrate) +{ + int err; + struct clk clk; + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); + + err = clk_get_by_index(dev, 0, &clk); + if (!err) { + err = clk_get_rate(&clk); + if (!IS_ERR_VALUE(err)) + platdata->clock = err; + } else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) { + debug("SiFive UART failed to get clock\n"); + return err; + } + + if (!platdata->clock) + platdata->clock = dev_read_u32_default(dev, "clock-frequency", 0); + if (!platdata->clock) { + debug("SiFive UART clock not defined\n"); + return -EINVAL; + } + + _sifive_serial_setbrg(platdata->regs, platdata->clock, baudrate); + + return 0; +} + +static int sifive_serial_probe(struct udevice *dev) +{ + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); + + /* No need to reinitialize the UART after relocation */ + if (gd->flags & GD_FLG_RELOC) + return 0; + + _sifive_serial_init(platdata->regs); + + return 0; +} + +static int sifive_serial_getc(struct udevice *dev) +{ + int c; + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); + struct uart_sifive *regs = platdata->regs; + + while ((c = _sifive_serial_getc(regs)) == -EAGAIN) ; + + return c; +} + +static int sifive_serial_putc(struct udevice *dev, const char ch) +{ + int rc; + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); + + while ((rc = _sifive_serial_putc(platdata->regs, ch)) == -EAGAIN) ; + + return rc; +} + +static int sifive_serial_ofdata_to_platdata(struct udevice *dev) +{ + struct sifive_uart_platdata *platdata = dev_get_platdata(dev); + + platdata->regs = (struct uart_sifive *)dev_read_addr(dev); + if (IS_ERR(platdata->regs)) + return PTR_ERR(platdata->regs); + + return 0; +} + +static const struct dm_serial_ops sifive_serial_ops = { + .putc = sifive_serial_putc, + .getc = sifive_serial_getc, + .setbrg = sifive_serial_setbrg, +}; + +static const struct udevice_id sifive_serial_ids[] = { + { .compatible = "sifive,uart0" }, + { } +}; + +U_BOOT_DRIVER(serial_sifive) = { + .name = "serial_sifive", + .id = UCLASS_SERIAL, + .of_match = sifive_serial_ids, + .ofdata_to_platdata = sifive_serial_ofdata_to_platdata, + .platdata_auto_alloc_size = sizeof(struct sifive_uart_platdata), + .probe = sifive_serial_probe, + .ops = &sifive_serial_ops, + .priv_auto_alloc_size = sizeof(struct sifive_uart_platdata), +}; + +#ifdef CONFIG_DEBUG_UART_SIFIVE +static inline void _debug_uart_init(void) +{ + struct uart_sifive *regs = + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; + + _sifive_serial_setbrg(regs, CONFIG_DEBUG_UART_CLOCK, + CONFIG_BAUDRATE); + _sifive_serial_init(regs); +} + +static inline void _debug_uart_putc(int ch) +{ + struct uart_sifive *regs = + (struct uart_sifive *)CONFIG_DEBUG_UART_BASE; + + while (_sifive_serial_putc(regs, ch) == -EAGAIN) + WATCHDOG_RESET(); +} + +DEBUG_UART_FUNCS + +#endif
This patch adds SiFive UART driver. The driver is 100% DM driver and it determines input clock using clk framework. Signed-off-by: Anup Patel <anup@brainfault.org> --- drivers/serial/Kconfig | 13 +++ drivers/serial/Makefile | 1 + drivers/serial/serial_sifive.c | 193 +++++++++++++++++++++++++++++++++ 3 files changed, 207 insertions(+) create mode 100644 drivers/serial/serial_sifive.c